Cooling, heating and power multipurpose heat pump system

Abstract

The invention relates to the field of engines, refrigerators and heat pumps, in particular to a cooling, heating and power multipurpose heat pump system which comprises a first heat exchanger, a compressor, a second heat exchanger and expansion devices which are sequentially connected and further comprises a motor, and the expansion devices comprise the first expansion device and the second expansion device. The first-class expansion devices are expansion machines for recycling expansion work in the working medium expansion process and outputting mechanical work, and the number X of the first-class expansion devices is larger than or equal to 1; the second-class expansion devices are expansion devices except the expansion machine, and the number Y of the second-class expansion devices is larger than or equal to 1; the second expansion device comprises an electronic expansion valve and the like; the cooling, heating and power multipurpose heat pump system has two operation modes. The first operation mode is refrigeration cycle, and the cooling, heating and power multipurpose heat pump system consumes electric quantity and generates cold energy and heat energy; and the second operation mode is power circulation, and the cooling, heating and power multipurpose heat pump system consumes cold and heat to generate electric quantity. The system has the advantages of multiple functions, high efficiency, good economical efficiency, high reliability and the like.

Description

Technical Field

[0001] The invention relates to the fields of engines, refrigerators and heat pumps, and in particular to a multi-purpose heat pump system for cooling, heating and electricity. Background Art

[0002] Heat pump systems are usually used to provide cooling or heat. In order to improve the energy utilization rate of the whole society and reduce operating costs, the industry has proposed to produce cooling / heating during the low electricity consumption period at night when the power load is very low, and store the cooling / heating, and release the stored cooling / heating during the day when the power load is high, that is, during the peak electricity consumption period, to meet the cooling / heating needs. However, on the one hand, cooling storage is mainly through ice making, and heat storage is mainly through related phase change media or sensible heat materials. Due to the small working temperature difference, it is difficult to take into account both the operating efficiency and the cooling / heat storage density when storing cooling / heating. On the other hand, since the cooling / heating demand is affected by seasonality, the energy storage method based on cooling or heat storage and directly used for cooling / heating needs does not run for a long time throughout the year, resulting in poor economic efficiency.

[0003] In recent years, the application of heat pump systems in the field of power storage has gradually gained relevant attention. The system converts the electric energy during the low-power period at night into high-temperature heat and low-temperature heat through a reverse cycle and stores them separately, and then converts the stored high-temperature heat and low-temperature cold into electric energy during the peak power period through a forward cycle. This heat pump for power storage needs is quite different from the existing heat pumps for cooling or heat needs in terms of working temperature difference, cycle, working fluid, and device design. For example, the temperature difference between the average temperature of high-temperature heat and the average temperature of low-temperature heat in heat pump systems for power storage needs is usually 100-600℃, and the temperature difference between the average temperature of high-temperature heat and the average temperature of low-temperature heat in heat pump systems for cold or heat storage is usually 20-80℃. Therefore, it is very difficult to efficiently meet the cooling or heat demand and power storage demand through a set of system heat pump systems. This is also the reason why the heat pump systems currently used to meet the cooling / heating needs while taking into account energy storage are mainly limited to the cold / heat storage and direct use of cold / heat energy storage methods. In addition, the industry has also proposed some heat pump systems that meet the needs of electricity storage and take into account the needs of cooling / heating, such as: Patent CN106224040B and Patent CN110206599B. This type of system mainly uses stored heat and cold for heating, cooling and power generation. Since the cold and heat for its cooling / heating needs are obtained from the cold and heat storage used for power generation needs, and the cold and heat storage used for power generation needs usually have a large working temperature difference, the cold and heat used for power generation needs are generated under a large temperature difference. When it is used for cooling / heating needs, the cold / heat temperature difference is usually low, thus leading to low efficiency. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a multi-purpose heat pump system for cooling, heating and electricity. The system includes a mass regulating device, which regulates the pressure in the heat pump system, so that the heat pump system can switch between different operating cycles under different application requirements. At the same time, in order to solve the damage of the liquid to the expander in the vapor compression cycle, the system also includes two types of expansion devices. When facing cold or hot needs, the pressure in the heat pump system is regulated by the mass regulating device, so that the system cycle can achieve or approach the vapor compression cycle, and the expansion device other than the expander is fully or mainly used for working fluid expansion, so as to achieve high performance, high reliability and low cost in the process facing cold or hot needs; when facing power storage needs, the pressure in the heat pump system is regulated by the mass regulating device, so that the system cycle can achieve or approach the Brayton cycle or the reverse Brayton cycle, and the expander is fully or mainly used to recover the expansion work, so as to achieve high performance in the process facing power storage needs. Therefore, a set of heat pump systems can efficiently meet different application requirements, thereby having the advantages of multiple functions, high efficiency, good economy and high reliability.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: a multi-purpose heat pump system for cooling, heating and electricity, comprising a first heat exchanger, a compressor, a second heat exchanger, an expansion device connected in sequence, and a motor, characterized in that: the expansion device comprises a first type of expansion device and a second type of expansion device;

[0006] The first type of expansion device is an expander that recovers the expansion work of the working medium expansion process and outputs mechanical work, and the number of the first type of expansion devices X ≥ 1;

[0007] The second type of expansion device is an expansion device other than an expander, and the number of the second type of expansion devices Y ≥ 1;

[0008] The multi-purpose heat pump system for cooling, heating and power has at least two working fluid circuits, the first working fluid circuit is composed of a first type of expansion device and a compressor, and the second working fluid circuit is composed of a second type of expansion device and a compressor and / or a first type of expansion device, wherein: in the first working fluid circuit, the inlet of the compressor is connected to the outlet end of the second heat exchanger, the outlet of the compressor is connected to the inlet end of the first heat exchanger, the inlet of the first type of expansion device is connected to the outlet end of the first heat exchanger, the outlet of the first type of expansion device is connected to the inlet end of the second heat exchanger, and two pipelines are formed between the compressor and the first type of expansion device, the first pipeline includes a connecting pipeline between the outlet of the compressor and the inlet of the first type of expansion device, and the second pipeline includes a connecting pipeline between the inlet of the compressor and the outlet of the first type of expansion device; in the second working fluid circuit, one interface of the second type of expansion device is connected to the first pipeline, and the other interface of the second type of expansion device is connected to the second pipeline;

[0009] It also includes a mass regulating device, which includes a working fluid storage tank and a control valve. The control valve has the function of controlling the connection and disconnection between the working fluid storage tank and the working fluid in the multi-purpose heat pump system, pumping the working fluid in the multi-purpose heat pump system into the working fluid storage tank for storage or releasing the working fluid stored in the working fluid storage tank into the working fluid in the multi-purpose heat pump system, so as to regulate the total mass of the working fluid in the multi-purpose heat pump system;

[0010] The multi-purpose heat pump system for cooling, heating and electricity contains at least one working fluid with a critical temperature higher than 300K;

[0011] The multi-purpose heat pump system for cooling, heating and electricity has two operation modes;

[0012] The first operation mode is a refrigeration cycle, wherein the cold, heat and electric multi-purpose heat pump system consumes electricity and generates cold and heat;

[0013] The second operation mode is a power cycle, in which the cold, heat and electricity multi-purpose heat pump system consumes cold and heat to generate electricity.

[0014] Furthermore, the multi-purpose heat pump system for cooling, heating and electricity also includes a working fluid with a critical temperature lower than 300K;

[0015] When operating in the first operating mode and when the operating working fluid working temperature difference is less than 60°C, the mass regulating device is used to control the mass flow of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to account for more than 50% of the total working fluid mass flow, and the mass flow of the working fluid with a critical temperature lower than 300K to account for less than 50% of the total working fluid mass flow;

[0016] When operating in the first operating mode and when the operating working fluid working temperature difference is greater than 100°C, the mass regulating device is used to control the mass flow of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to account for less than 50% of the total working fluid mass flow, and the mass flow of the working fluid with a critical temperature lower than 300K to account for more than 50% of the total working fluid mass flow;

[0017] When operating in the second operating mode and when the operating working fluid operating temperature difference is greater than 100°C, the mass regulating device is used to control the mass flow rate of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to be less than 50% of the total working fluid mass flow rate, and the mass flow rate of the working fluid with a critical temperature lower than 300K to be greater than 50% of the total working fluid mass flow rate.

[0018] Further, a multi-purpose heat pump system for cooling, heating and electricity comprises a first heat exchanger, a compressor, a second heat exchanger, an expansion device connected in sequence, and a motor, wherein the expansion device comprises a first type of expansion device and a second type of expansion device;

[0019] The first type of expansion device is an expander that recovers the expansion work of the working medium expansion process and outputs mechanical work, and the number of the first type of expansion devices X ≥ 1;

[0020] The second type of expansion device is an expansion device other than an expander, and the number of the second type of expansion devices Y ≥ 1;

[0021] The multi-purpose heat pump system for cooling, heating and power has at least two working fluid circuits, the first working fluid circuit is composed of a first type of expansion device and a compressor, and the second working fluid circuit is composed of a second type of expansion device and a compressor and / or a first type of expansion device, wherein: in the first working fluid circuit, the inlet of the compressor is connected to the outlet end of the second heat exchanger, the outlet of the compressor is connected to the inlet end of the first heat exchanger, the inlet of the first type of expansion device is connected to the outlet end of the first heat exchanger, the outlet of the first type of expansion device is connected to the inlet end of the second heat exchanger, and two pipelines are formed between the compressor and the first type of expansion device, the first pipeline includes a connecting pipeline between the outlet of the compressor and the inlet of the first type of expansion device, and the second pipeline includes a connecting pipeline between the inlet of the compressor and the outlet of the first type of expansion device; in the second working fluid circuit, one interface of the second type of expansion device is connected to the first pipeline, and the other interface of the second type of expansion device is connected to the second pipeline;

[0022] It also includes a mass regulating device, which includes a working fluid storage tank and a control valve. The control valve has the function of controlling the connection and disconnection between the working fluid storage tank and the working fluid in the multi-purpose heat pump system, pumping the working fluid in the multi-purpose heat pump system into the working fluid storage tank for storage or releasing the working fluid stored in the working fluid storage tank into the working fluid in the multi-purpose heat pump system, so as to regulate the total mass of the working fluid in the multi-purpose heat pump system;

[0023] The multi-purpose heat pump system for cooling, heating and electricity contains at least one working fluid with a critical temperature higher than 300K;

[0024] The multi-purpose heat pump system for cooling, heating and electricity contains at least one working fluid with a critical temperature lower than 300K;

[0025] The multi-purpose heat pump system for cooling, heating and electricity has two operation modes;

[0026] The first operation mode is a refrigeration cycle, wherein the cold, heat and electric multi-purpose heat pump system consumes electricity and generates cold and heat;

[0027] The second operation mode is a power cycle, in which the cold, heat and electricity multi-purpose heat pump system consumes cold and heat to generate electricity.

[0028] Further, the connection point between an interface of the second type expansion device and the first pipeline includes the outlet of the compressor, the inlet of the first type expansion device, and the connecting pipeline between the outlet of the compressor and the inlet of the first type expansion device;

[0029] The connection point between the other interface of the second type expansion device and the second pipeline includes the inlet of the compressor, the outlet of the second type expansion device, and the connecting pipeline between the inlet of the compressor and the outlet of the first type expansion device.

[0030] Further, when operating in the first operating mode, and when the operating temperature difference of the operating working fluid is less than 60°C, the mass flow rate of the liquid working fluid at the inlet and / or outlet of at least one expansion device is controlled to account for more than 10% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the second type of expansion device in the multi-purpose heat pump system for cooling, heating and electricity is controlled to account for more than 90% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the first type of expansion device in the multi-purpose heat pump system for cooling, heating and electricity is controlled to account for less than 10% of the total mass flow rate of the working fluid;

[0031] When operating in the first operating mode, and when the operating temperature difference of the operating working fluid is greater than 100°C, the mass flow rate of the liquid working fluid at the inlet of at least one expansion device is controlled to account for less than 10% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the second type of expansion device in the cold, heat and electricity multi-purpose heat pump system is controlled to account for less than 10% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the first type of expansion device in the cold, heat and electricity multi-purpose heat pump system is controlled to account for more than 90% of the total mass flow rate of the working fluid;

[0032] When operating in the second operating mode, and when the operating temperature difference of the operating working fluid is greater than 100°C, the proportion of the mass flow rate of the liquid working fluid at the inlet of at least one expansion device to the total mass flow rate of the working fluid is controlled to be ≤10%; the proportion of the mass flow rate of the working fluid passing through the second type of expansion device in the multi-purpose heat pump system for cooling, heating and power is controlled to be less than 10% of the total mass flow rate of the working fluid, and the proportion of the mass flow rate of the working fluid passing through the first type of expansion device in the multi-purpose heat pump system for cooling, heating and power is controlled to be greater than 90% of the total mass flow rate of the working fluid.

[0033] Further, when operating in the first operating mode and the operating working fluid operating temperature difference is less than 60°C, the operating working fluid is controlled to operate according to the second working fluid circuit; when operating in the first operating mode and the operating working fluid operating temperature difference is greater than 100°C, the operating working fluid is controlled to operate according to the first working fluid circuit; when operating in the second operating mode and the operating working fluid operating temperature difference is greater than 100°C, the operating working fluid is controlled to operate according to the first working fluid circuit.

[0034] Further, when operating in the first operating mode and the operating working fluid working temperature difference is less than 60°C, X≥1 first-type expansion devices are controlled to stop being used for working fluid expansion; when operating in the first operating mode and the operating working fluid working temperature difference is greater than 100°C, Y≥1 second-type expansion devices are controlled to stop being used for working fluid expansion; when operating in the second operating mode and the operating working fluid working temperature difference is greater than 100°C, Y≥1 second-type expansion devices are controlled to stop being used for working fluid expansion.

[0035] Furthermore, it also includes a first heat storage device and a second heat storage device;

[0036] The heat exchange between the heat storage device and the working medium can be achieved in any of the following situations:

[0037] The heat transfer medium from the heat storage device flows into the heat storage device after completing heat exchange with the working medium in the first heat exchanger and / or the second heat exchanger;

[0038] And / or, the heat storage device is connected in parallel with the heat exchanger, and the working fluid directly exchanges heat with the heat storage device.

[0039] Furthermore, the expansion device has an unloading operation mechanism, which is used to reduce additional losses generated when the first type expansion device and / or the second type expansion device are not used for working medium expansion during the operation of the heat pump.

[0040] Further, the unloading operation mechanism includes a clutch and a valve;

[0041] When the unloading operation mechanism is a valve, the valve is arranged on the inlet or outlet pipeline of the expansion device.

[0042] Further, when the first-type expansion device can be used for working fluid compression, the first-type expansion device is used for compressing the working fluid in the second working fluid circuit, including any of the following situations:

[0043] The working fluid is all compressed in the first type of expansion device, and the working fluid is expanded through the second type of expansion device;

[0044] and / or, part of the working fluid from the second heat exchanger is compressed in the first type expansion device, the other part is compressed in the compressor, and the working fluid is expanded through the second type expansion device;

[0045] and / or, the first type expansion device is connected in series with the compressor, the working fluid flows into the first type expansion device for pre-compression and flows into the compressor for secondary compression, and the working fluid expands through the second type expansion device;

[0046] And / or, the first type expansion device is connected in series with the compressor, the working fluid flows into the compressor for pre-compression and flows into the first type expansion device for secondary compression, and the working fluid expands through the second type expansion device.

[0047] Furthermore, the compressor is composed of a compression module control valve and N≥2 compression modules.

[0048] Further, under the action of the compression module control valve, the first type of expansion device is ≥1 compression module of the compressor, that is, ≥1 compression module is used to recover the expansion work of the working fluid expansion process and output mechanical work;

[0049] When operating in the first operating mode and the working temperature difference of the operating working fluid is greater than 100°C, under the action of the compression module control valve, K≥1 compression modules are used for working fluid compression, J≥1 compression modules are used for working fluid expansion, and K+J≤N;

[0050] When operating in the second operating mode, K≥1 compression modules are used for working fluid compression, J≥1 compression modules are used for working fluid expansion, and K+J≤N.

[0051] Furthermore, the compressor is a positive displacement compressor having ≥1 air valve, the air valve being an intake valve and / or an exhaust valve, at least one of the air valves being an actively controlled valve, and the opening and closing of the actively controlled valve is controlled by electromagnetic force, hydraulic pressure or mechanical force;

[0052] And / or, the first type of expansion device is a volumetric expander having ≥1 gas valve, which is an intake valve and / or an exhaust valve, at least one of which is an actively controlled valve, and the opening and closing of the actively controlled valve is controlled by electromagnetic force, hydraulic pressure or mechanical force.

[0053] Furthermore, it also includes ≥2 mass regulating devices, wherein: at least one mass regulating device is used for mass regulating at least one working fluid with a critical temperature higher than 300K; at least one mass regulating device is used for mass regulating a working fluid with a critical temperature lower than 300K.

[0054] Furthermore, it also includes a regenerator, which has a first flow channel and a second flow channel. One end of the first flow channel of the regenerator is connected to the outlet end of the first heat exchanger, and the other end is connected to the inlet end of the first type of expansion device. One end of the second flow channel of the regenerator is connected to the outlet end of the second heat exchanger, and the other end is connected to the compressor.

[0055] Further, when the first type of expansion device cannot be used for working fluid compression, the number of compressors is ≥ 2, wherein: when operating in the first operating mode and when the operating working fluid working temperature difference is greater than 100° C., the compressor used for working fluid compression is the first compressor, and when operating in the second operating mode and when the operating working fluid working temperature difference is greater than 100° C., the compressor used for working fluid compression is the second compressor;

[0056] When operating in the first operating mode and when the operating temperature difference of the operating working medium is less than 60° C., the second compressor is used for compressing the working medium in the second working medium circuit, including any of the following situations:

[0057] The working medium is completely compressed in the second compressor, and the working medium is expanded through the second type expansion device;

[0058] and / or, a portion of the working fluid is compressed in the second compressor and another portion is compressed in the first compressor, and the working fluid is expanded through a second type expansion device;

[0059] and / or, the first compressor is connected in series with the second compressor, the working fluid flows into the second compressor for pre-compression and flows into the first compressor for second compression, and the working fluid is expanded through the second type expansion device;

[0060] And / or, the first compressor is connected in series with the second compressor, the working fluid flows into the first compressor for pre-compression and flows into the second compressor for secondary compression, and the working fluid is expanded through a second type expansion device.

[0061] Furthermore, it also includes a third heat exchanger, wherein the third heat exchanger is located in the connecting pipeline between the compressor outlet and the inlet of the second type expansion device;

[0062] And / or, it also includes a fourth heat exchanger, which is located in the connecting pipeline between the outlet of the second type expansion device and the inlet of the compressor.

[0063] Furthermore, the second type of expansion device is an expansion device that cannot recover the expansion work of the working medium expansion process and outputs mechanical work;

[0064] The second type of expansion device includes electronic expansion valves, thermal expansion valves, capillary tubes, ejectors or orifice plates.

[0065] Furthermore, when operating in the first operating mode and when the operating working fluid working temperature difference is less than 60°C, the mass flow rate of the working fluid with a critical temperature higher than 300K in the multi-purpose heat pump system for heating, cooling and heating accounts for more than 50% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid with a critical temperature lower than 300K accounts for less than 50% of the total mass flow rate of the working fluid;

[0066] When operating in the first operating mode and when the operating working fluid working temperature difference is greater than 100°C, the mass flow rate of working fluids with a critical temperature higher than 300K in the multi-purpose heat pump system accounts for less than 50% of the total mass flow rate of working fluids, and the mass flow rate of working fluids with a critical temperature lower than 300K accounts for more than 50% of the total mass flow rate of working fluids;

[0067] When operating in the second operating mode and when the operating working fluid operating temperature difference is >100°C, the proportion of the working fluid mass flow rate with a critical temperature higher than 300K in the multi-purpose heat pump system to the total working fluid mass flow rate is <50%, and the proportion of the working fluid mass flow rate with a critical temperature lower than 300K to the total working fluid mass flow rate is >50%.

[0068] Furthermore, it also includes at least one gas separator, wherein the gas separator has a cavity inside and at least one interface communicating with the closed cavity;

[0069] The gas separator can achieve the following functions:

[0070] When operating in the first operating mode and the operating temperature difference of the operating working fluid is less than 60°C, the gas separator is used to reduce the proportion of the working fluid with a critical temperature below 300K in the total working fluid mass flow;

[0071] and / or, when operating in the first operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., the gas separator is used to reduce the proportion of the working fluid with a critical temperature higher than 300K in the total working fluid mass flow;

[0072] And / or, when operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., the gas separator is used to reduce the proportion of the working fluid with a critical temperature higher than 300K in the total working fluid mass flow rate.

[0073] Furthermore, the gas separator can be connected in any of the following ways:

[0074] A first gas separator is connected to a connecting pipeline between an interface of the second type expansion device and an outlet of the compressor;

[0075] And / or, the second gas separator is connected to the first pipeline, or, the second gas separator is connected to the second pipeline, or, the second gas separator is connected to the connecting pipeline between the compressor outlet and the second type of expansion device, or, the second gas separator is connected to the connecting pipeline between the compressor inlet and the second type of expansion device.

[0076] Further, when operating in the first operating mode and the operating working medium working temperature difference is greater than 100°C, the temperature of the liquid in the first gas separator and / or the second gas separator is controlled to be ≤273K, so as to achieve that part of the working medium with a critical temperature higher than 300K is stored in the first gas separator and / or the second gas separator in a liquid state; when operating in the second operating mode and the operating working medium working temperature difference is greater than 100°C, the temperature of the liquid in the first gas separator and / or the second gas separator is controlled to be ≤273K, so as to achieve that part of the working medium with a critical temperature higher than 300K is stored in the second gas separator in a liquid state;

[0077] When operating in the first operating mode or the second operating mode, and the operating working medium working temperature difference is greater than 100°C, the first gas separator or the second gas separator stores a portion of liquid working medium with a critical temperature higher than 300K, and the liquid working medium may be generated in any of the following situations:

[0078] The working fluid with a critical temperature higher than 300K entering the first gas separator or the second gas separator is in liquid phase or gas-liquid two-phase;

[0079] The working fluid with a critical temperature higher than 300K entering the first gas separator or the second gas separator is in gas phase, and the gas phase working fluid is condensed into liquid in the first gas separator or the second gas separator.

[0080] Furthermore, the gas separator includes a storage tank and a bent pipe.

[0081] Furthermore, it also includes a switching valve, a first switching valve is located at the compressor outlet, and is used to control the connection and disconnection between the compressor outlet and the first heat exchanger or the third heat exchanger; the second switching valve is located at the compressor inlet, and is used to control the connection between the compressor inlet and the second heat exchanger or the fourth heat exchanger.

[0082] Furthermore, when operating in the first operating mode or the second operating mode and the operating temperature difference of the operating working fluid is >100°C, part of the working fluid with a critical temperature higher than 300K is stored in liquid form in the third heat exchanger or the fourth heat exchanger, and the liquid temperature in the third heat exchanger or the fourth heat exchanger is controlled to be ≤273K.

[0083] Further, when operating in the first operating mode and when the operating temperature difference of the operating working fluid is greater than 100° C., in the first working fluid circuit, the pressure in the first heat exchanger and the second heat exchanger is greater than or equal to 0.5 MPa;

[0084] When operating in the second operating mode and when the operating temperature difference of the operating working fluid is greater than 100° C., in the first working fluid circuit, the pressure in the first heat exchanger and the second heat exchanger is greater than or equal to 0.5 MPa.

[0085] Compared with the prior art, the advantages of the present invention are:

[0086] The multi-purpose heat pump system for heating, cooling and electricity disclosed in the present invention adjusts the pressure in the heat pump system through a mass regulating device, and through two types of expansion devices, can realize a set of equipment to meet the high efficiency requirements of different application requirements, and can also solve the reliability problem of the expansion machine used in the steam compression cycle. Therefore, the multi-purpose heat pump system for heating, cooling and electricity has the advantages of multiple functions, high efficiency, good economy and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] Figure 1 It is a structural schematic diagram of the multi-purpose heat pump system of cooling, heating and electricity of the present invention.

[0088] Figure 2 a is a first structural schematic diagram of the present invention's multi-purpose heat pump system for heating, cooling and electricity based on four heat exchangers with different working fluid loops.

[0089] Figure 2 b is a first structural schematic diagram of the multi-purpose heat pump system for heating, cooling and electricity based on three heat exchangers with different working fluid circuits according to the present invention.

[0090] Figure 2 c is a first structural schematic diagram of the multi-purpose heat pump system for heating, cooling and electricity based on two heat exchangers with different working fluid loops according to the present invention.

[0091] Figure 2 d is a second structural schematic diagram of the multi-purpose heat pump system for heating, cooling and electricity with different working fluid loops based on three heat exchangers of the present invention.

[0092] Figure 2 e is a second structural schematic diagram of the multi-purpose heat pump system for heating, cooling and electricity based on two heat exchangers with different working fluid loops according to the present invention.

[0093] Figure 2 f is a second structural schematic diagram of the multi-purpose heat pump system for heating, cooling and electricity with different working fluid loops based on four heat exchangers of the present invention.

[0094] Figure 2 g is a third structural schematic diagram of the multi-purpose heat pump system for heating, cooling and electricity based on two heat exchangers with different working fluid circuits according to the present invention.

[0095] Figure 2 h is a schematic diagram of the structure of the multi-purpose heat pump system for cooling, heating and electricity based on different working fluid circuits with connection positions located on the heat exchanger of the present invention.

[0096] Figure 3 It is a schematic diagram of the operation mode of the multi-purpose heat pump system of cooling, heating and electricity of the present invention.

[0097] Figure 4a is a schematic diagram of the structure of a multi-purpose heat pump system for cooling, heating and electricity in which an expander and a compressor are connected in parallel for working fluid compression.

[0098] Figure 4 b is a schematic diagram of the structure of a multi-purpose heat pump system for cooling, heating and electricity in which the expander and the compressor are connected in series and the expander is the front-stage compression.

[0099] Figure 4 c is a schematic diagram of the structure of a multi-purpose heat pump system for heating, cooling and electricity in which the expander and the compressor are connected in series and the expander is the latter stage compression.

[0100] Figure 5 It is a schematic diagram of the structure of a multi-purpose heat pump system for cooling, heating and electricity in which the compression module of the present invention is used for working fluid expansion.

[0101] Figure 6 It is a schematic diagram of the structure of the multi-purpose heat pump system of the present invention including a working fluid with a critical temperature lower than 300K.

[0102] Figure 7 It is a schematic structural diagram of the multi-purpose heat pump system of cold, heat and electricity with a heat regenerator of the present invention.

[0103] Figure 8 a is a schematic diagram of the structure of a multi-purpose heat pump system for cooling, heating and electricity in which a first compressor and a second compressor are connected in parallel for working fluid compression.

[0104] Figure 8 b is a schematic diagram of the structure of a multi-purpose heat pump system for cooling, heating and electricity in which the first compressor and the second compressor are connected in series and the second compressor is the front-stage compressor.

[0105] Figure 8 c is a schematic diagram of the structure of a multi-purpose heat pump system for cooling, heating and electricity in which the first compressor and the second compressor are connected in series and the second compressor is the latter stage compressor.

[0106] Figure 8 d is a schematic structural diagram of the multifunctional cooling, heating and electricity multi-purpose heat pump system of the present invention in which the first compressor and the second compressor are connected in parallel and in series.

[0107] Fig. 9 It is a schematic diagram of the structure of the multi-purpose heat pump system for cooling, heating and electricity based on turbine machinery of the present invention.

[0108] Fig.10 It is a schematic structural diagram of the multi-purpose heat pump system for cooling, heating and electricity based on a switching valve and a working fluid pump of the present invention.

[0109] Fig.11 a is a first structural schematic diagram of the multi-purpose heat pump system of cooling, heating and electricity based on a gas separator of the present invention.

[0110] Fig.11b is a second structural schematic diagram of the multi-purpose heat pump system of cooling, heating and electricity based on a gas separator of the present invention.

[0111] Fig.11 c is a third structural schematic diagram of the multi-purpose heat pump system for cooling, heating and electricity based on a gas separator of the present invention.

[0112] Fig.11 d is a fourth structural schematic diagram of the multi-purpose heat pump system for cooling, heating and electricity based on a gas separator of the present invention.

[0113] Wherein: 101, first heat exchanger; 102, second heat exchanger; 103, third heat exchanger; 104, fourth heat exchanger; 105, fifth heat exchanger; 106, sixth heat exchanger; 2, compressor; 201, first compressor; 202, second compressor; 2001, first compression module; 2002, second compression module; 3, expansion device; 301, first type expansion device; 302, second type expansion device; 3010, first first type expansion device; 3011, second first type expansion device; 4, quality control device; 5, working fluid storage tank; 6, control valve; 7, working fluid pump; 801, first heat storage device; 802, second heat storage device ;901, first valve; 902, second valve; 903, third valve; 904, fourth valve; 905, fifth valve; 906, sixth valve; 907, seventh valve; 908, eighth valve; 909, ninth valve; 10, regenerator; 12, motor; 13, clutch; 1401, first compression module control valve; 1402, second compression module control valve; 1403, third compression module control valve; 1404, fourth compression module control valve; 15, gas separator; 1601, first gas separation control valve; 1602, second gas separation control valve; 1701, first switching valve; 1702, second switching valve. DETAILED DESCRIPTION

[0114] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0115] First, heat pumps for cooling or heat demand are usually based on vapor compression cycles, which have high efficiency on the one hand, and on the other hand, the working fluid in the vapor compression cycle absorbs or releases heat through phase change, the working fluid flow is small, and the compressor cost is low; based on the reverse Brayton cycle, the efficiency is usually low in applications for cooling or heat demand, and the sensible heat absorption or release leads to a large working fluid flow and high compressor cost. Therefore, heat pumps based on the reverse Brayton cycle are relatively rare in applications for cooling or heat demand. Furthermore, cooling or heat demand refers to evaporation temperature>-70℃ and condensation temperature<120℃.

[0116] Secondly, the working fluid will undergo phase change in the vapor compression cycle. However, the droplets generated in the phase change process will cause cavitation or liquid impact on the expander, thereby damaging the expander. On the other hand, due to the small operating temperature difference during the cooling or heat demand process, the recoverable expansion work is small. Therefore, it is appropriate to use non-expander expansion devices, such as electronic expansion valves, thermal expansion valves, capillaries, ejectors or orifice plates, etc. This is the reason why expanders are rarely used in heat pump systems for cooling / heating needs. Heat pumps for power storage needs have large operating temperature differences and large recoverable expansion work. Failure to recover the expansion work will result in very low electricity-to-electricity conversion efficiency, resulting in loss of economy. Therefore, it is appropriate to use expanders that recover expansion work, and it is suitable to use Brayton or reverse Brayton cycles.

[0117] Finally, electricity storage is achieved through the conversion of heat storage and cold storage. Heat pumps based on vapor compression cycles will produce phase changes, so the heat storage materials need to be precisely matched with their phase change temperature, which makes it difficult to obtain such phase change materials. Heat pumps based on reverse Brayton cycles do not undergo phase changes, so large temperature sliding heat exchange can be used. Therefore, it is easy to achieve high energy density heat storage and cold storage.

[0118] In addition, the cost of non-expander expansion devices is low. When used for cooling or heat demand applications, such expansion devices are used to replace the expansion function of the expander. The expander can also be used for compression. Therefore, there are three compressors with different capabilities in the heat pump system: only the expander assumes the compression function under small-scale cooling / heating, only the compressor assumes the compression function under medium-scale cooling / heating, and the expander and compressor jointly assume the compression function under large-scale cooling / heating, thereby improving the performance of the heat pump system under different loads and reducing the demand for compressors and compressor costs. Moreover, the expander can also be connected in series with the compressor to act as the first or last stage of compression of the compressor to improve the performance of the compressor. In addition, the multi-purpose heat pump system of the cold and hot electric heat pump can also use the waste heat generated during the power storage process to provide relevant heat for related heat needs and improve energy utilization.

[0119] In summary, the multi-purpose heat pump system for heating, cooling and electricity uses different expansion devices, different working fluids and mass adjustment devices to control the operating pressure or a gas separation method based on gas-liquid separation to adjust the proportion of different working fluids in the total working fluid mass flow rate under different applications. According to application requirements, the heat pump system can realize (or approach) the vapor compression cycle and the reverse Brayton cycle during operation, and select the most suitable "compressor" according to the load. It can also utilize the waste heat in the process of storage and power conversion, thus having the advantages of multiple functions, high efficiency, high reliability and low cost.

[0120] Embodiment 1:

[0121] like Figure 1As shown, this embodiment provides a multi-purpose heat pump system for cooling, heating and electricity, including a first heat exchanger 101, a compressor 201, a second heat exchanger 102, an expansion device connected in sequence, and a motor 12. The motor 12 can be a motor and / or a generator. The motor consumes electricity to generate mechanical work, and the generator consumes mechanical work to generate electricity. Preferably, the motor is an electric-generator integrated machine. The motor 12 is connected to the compressor 2. The number of expansion devices 3 is ≥2, and the types of expansion devices include first-class expansion devices and second-class expansion devices, wherein: the first-class expansion device is an expander that recovers the expansion work of the working fluid expansion process and outputs mechanical work. The expander can be a turbine expander or a volumetric expander. The volumetric expander includes a piston expander, a rotor expander, a vortex expander, a screw expander, etc. The first-class expansion device is connected to the compressor, and the mechanical work output by the first-class expansion device is used to drive the compressor. The number of first-class expansion devices is ≥1; the second-class expansion device is an expansion device other than the expander, that is, the second-class expansion device cannot recover the expansion work and output mechanical work to the motor, including a thermal expansion valve, an electronic expansion valve, a capillary, an ejector, an orifice plate, etc. The number of second-class expansion devices is ≥1, wherein the ejector can recover the expansion work but cannot output mechanical work. Therefore, the ejector is classified as a second-class expansion device. In some cases, such as when multiple modules are connected in parallel and share a motor, the number of first-class expansion devices and the number of second-class expansion devices depend on the number of parallel modules, which is usually less than 100. Preferably, the number of first-class expansion devices is ≤16 and the number of second-class expansion devices is ≤16. The multi-purpose heat pump system for cooling, heating and electricity has at least two working fluid circuits, the first working fluid circuit is composed of the first-class expansion device and the compressor 2, and the second working fluid circuit is composed of the second-class expansion device and the compressor 2 and / or the first-class expansion device.Compressors and expanders are usually very easy to distinguish in heat pump systems. In the present invention, since some types of compression or expansion devices, such as piston compressors or piston expanders, have a set of devices that can function as both a working fluid compression device and a working fluid expansion device, and when the multi-purpose heat pump system for heat and cold electricity is facing the needs of power storage applications, the same set of devices may be used for working fluid compression during power storage, that is, to play the role of a compressor, but may be used for working fluid expansion during discharge, that is, to play the role of an expander, or the same set of devices may be used for working fluid compression during discharge, that is, to play the role of a compressor, but may be used for working fluid expansion during power storage, that is, to play the role of an expander. Function, therefore, in order to clarify the compressor and the expander, the compressor and the expander in the multi-purpose heat pump system of cold, heat and electricity of the present invention refer to the multi-purpose heat pump system of cold, heat and electricity working in the refrigeration cycle mode, that is, the charging process for power storage needs, wherein: the compressor is a device for compressing the working fluid in the first working fluid circuit when operating in the first operating mode, and the expander, that is, the first type of expansion device, is a device for expanding the working fluid in the first working fluid circuit when operating in the first operating mode. It is further emphasized that it refers to the compressor and expander in the first working fluid circuit under rated conditions or maximum cooling and heating capacity, that is, maximum charging power conditions when the heat pump system operates in the first operating mode. In the first working medium circuit, the inlet of the compressor 2 is connected to the outlet of the second heat exchanger 102, the outlet of the compressor 2 is connected to the inlet of the first heat exchanger 101, the inlet of the first type of expansion device is connected to the outlet of the first heat exchanger 101, the outlet of the first type of expansion device is connected to the inlet of the second heat exchanger 102, and two pipelines are formed between the compressor 2 and the first type of expansion device. The first pipeline includes a connecting pipeline between the outlet of the compressor 2 and the inlet of the first type of expansion device 301, and the second pipeline includes a connecting pipeline between the inlet of the compressor 2 and the outlet of the first type of expansion device 301; in the second working medium circuit, one interface of the second type of expansion device 302 is connected to the first pipeline, and the other interface of the second type of expansion device 302 is connected to the second pipeline. The inlet and outlet of the compressor 2, the inlet and outlet of the first type of expansion device, the inlet and outlet of the first heat exchanger 101, and the inlet and outlet of the second heat exchanger 102 are defined based on the working medium inlet and outlet state when the first working medium circuit operates in the first operating mode. Furthermore, one interface of the second type of expansion device and the first pipeline connection point include the outlet of compressor 2, the inlet of the first type of expansion device, and the connecting pipeline between the outlet of compressor 2 and the inlet of the first type of expansion device; another interface of the second type of expansion device and the second pipeline connection point include the inlet of compressor 2, the outlet of the second type of expansion device, and the connecting pipeline between the inlet of compressor 2 and the outlet of the first type of expansion device. Therefore, the connection position point includes the two ports of the first pipeline or the second pipeline and the connecting pipeline between the ports. The following situations are schematic diagrams of connection forms of connection points at different positions:.

[0122] (1) The connection point between one interface of the second type expansion device and the first pipeline is located at the inlet of the first type expansion device or on the connecting pipeline between the inlet of the first type expansion device and the outlet of the first heat exchanger 101, and the connection point between the other interface of the second type expansion device and the second pipeline is located at the outlet of the first type expansion device or on the connecting pipeline between the outlet of the first type expansion device and the inlet of the second heat exchanger 102. Figure 1 As shown, the second working medium circuit is composed of a compressor 2 , a first heat exchanger 101 , a second type expansion device 302 , and a second heat exchanger 102 . Figure 2 (a) shows another connection form, in which the interface of the second type expansion device 302 is connected to the first pipeline or the second pipeline through a heat exchanger, a third heat exchanger 103 is provided between one interface of the second type expansion device and the connection point of the first pipeline, and a fourth heat exchanger 104 is provided between another interface of the second type expansion device and the connection point of the second pipeline. The second working fluid circuit is composed of the compressor 2, the first heat exchanger 101, the third heat exchanger 103, the second type expansion device 302, the fourth heat exchanger 104, and the second heat exchanger 102. Although the third heat exchanger and the fourth heat exchanger are provided on the connecting pipeline between the interface of the second type expansion device and the first pipeline and the second pipeline, in this case, one interface of the second type expansion device is connected to the first pipeline and the other interface is connected to the second pipeline. See Figure 2 In (a), the second working medium circuit may also be composed of the third heat exchanger 103, the first type expansion device 301, the second type expansion device 302, and the fourth heat exchanger 104. In this case, the first type expansion device 301 replaces the compressor for working medium compression. When the first heat exchanger 101 and the second heat exchanger 102 are provided with a bypass pipe in parallel, the second working medium circuit may also be composed of the compressor 2, the first type expansion device 301, the third heat exchanger 103, the second type expansion device 302, and the fourth heat exchanger 104. The compressor 2 and the first type expansion device 301 are used for working medium compression at the same time. When the inlet and outlet of the first type expansion device 301 have directions, when the compressor 2 and the first type expansion device 301 are used for working medium compression at the same time, it is necessary to connect the inlet of the first type expansion 301 and the inlet of the compressor 2 to the outlet of the fourth heat exchanger 104 through a four-way valve or multiple valves, and connect the outlet of the first type expansion 301 and the outlet of the compressor 2 to the inlet of the third heat exchanger 103.

[0123] (2) The connection point between one interface of the second type expansion device and the first pipeline is located at the inlet of the first type expansion device or on the connecting pipeline between the inlet of the first type expansion device and the outlet of the first heat exchanger 101, and the connection point between the other interface of the second type expansion device and the second pipeline is located at the inlet of the compressor or on the connecting pipeline between the inlet of the compressor and the outlet of the second heat exchanger 102. Figure 2As shown in (b), it also includes a fifth heat exchanger 105, one end of the fifth heat exchanger 105 is connected to the second type expansion device 302, and the other end is connected to the compressor 2. The second working fluid circuit is composed of the compressor 2, the first heat exchanger 101, the second type expansion device 302, and the fifth heat exchanger 105. As mentioned above, although the fifth heat exchanger 105 is provided on the connecting pipeline between the interface of the second type expansion device and the second pipeline, in this case, it is still satisfied that one interface of the second type expansion device is connected to the first pipeline, and the other interface is connected to the second pipeline. Figure 2 (c) in the figure shows another connection form. In the first working fluid circuit, the first valve 901 is opened and the second valve 902 is closed. The first working fluid circuit is composed of the compressor 2, the first heat exchanger 101, the first type of expansion device 301, the second heat exchanger 102, and the first valve 901. In the second working fluid circuit, the second valve 902 is opened and the first valve 901 is closed. The second working fluid circuit is composed of the compressor 2, the first heat exchanger 101, the second type of expansion device 302, the second heat exchanger 102, and the second valve 902. In this case, although the first valve 901 is provided between the inlet of the compressor 2 and the outlet of the second heat exchanger 102 and is closed in the second working fluid circuit, the inlet of the compressor 2 and the outlet of the second heat exchanger 102 are connected in the first working fluid circuit, and the connection point between the other interface of the second type of expansion device and the second pipeline can be located at the inlet of the compressor or on the connecting pipeline between the inlet of the compressor and the second heat exchanger 102, which still satisfies the requirement that one interface of the second type of expansion device is connected to the first pipeline and the other interface is connected to the second pipeline.

[0124] (3) The connection point between one interface of the second type expansion device and the first pipeline is located at the outlet of the compressor 2 or on the connecting pipeline between the outlet of the compressor 2 and the inlet of the first heat exchanger 101, and the connection point between the other interface of the second type expansion device and the second pipeline is located at the outlet of the first type expansion device or on the connecting pipeline between the outlet of the first type expansion device and the inlet of the second heat exchanger 102. Figure 2 As shown in (d) in the figure, it also includes a fifth heat exchanger 105, one end of the fifth heat exchanger 105 is connected to the connecting pipeline between the compressor 2 outlet or the compressor 2 outlet and the first heat exchanger 101, and the other end is connected to the inlet of the second type expansion device 302. The second working fluid circuit is composed of the compressor 2, the fifth heat exchanger 105, the second type expansion device 302, and the second heat exchanger 102. In this case, although one end of the second type expansion device 302 is connected to the first pipeline through the fifth heat exchanger 105, as mentioned above, it still satisfies the requirement that one interface of the second type expansion device is connected to the first pipeline and the other interface is connected to the second pipeline. Figure 2 (e) in FIG. 1 shows another connection form, such as Figure 2As shown in (e), in the first working fluid circuit, the third valve 903 is opened and the fourth valve 904 is closed, and the first working fluid circuit is composed of the compressor 2, the third valve 903, the first heat exchanger 101, the first type of expansion device 301, and the second heat exchanger 102; in the second working fluid circuit, the third valve 903 is closed and the fourth valve 904 is opened, and the second working fluid circuit is composed of the compressor 2, the fourth valve 904, the first heat exchanger 101, the second type of expansion device 302, and the second heat exchanger 102. In this case, as described above, in the first working fluid circuit, although the third valve 903 is provided between the outlet of the compressor 2 and the inlet of the first heat exchanger 101 and is closed in the second working fluid circuit, in the first working fluid circuit, the outlet of the compressor 2 and the inlet of the first heat exchanger 101 are connected, and one interface of the second type of expansion device is connected to the connecting pipeline between the outlet of the compressor 2 and the inlet of the first heat exchanger 101, which still satisfies that one interface of the second type of expansion device is connected to the first pipeline and the other interface is connected to the second pipeline.

[0125] (4) The connection point between one interface of the second type expansion device and the first pipeline is located at the outlet of the compressor 2 or on the connecting pipeline between the outlet of the compressor 2 and the inlet of the first heat exchanger 101, and the connection point between the other interface of the second type expansion device and the second pipeline is located at the inlet of the compressor or on the connecting pipeline between the inlet of the compressor and the outlet of the second heat exchanger 102. Figure 2 As shown in (f) in FIG. 1 , the third heat exchanger 103 and the fourth heat exchanger 104 are also included. The second working medium circuit is composed of the compressor 2, the third heat exchanger 103, the second type expansion device 302, and the fourth heat exchanger 104. Figure 2(g) in the figure shows another connection form, in which the fourth valve 904 and the first valve 901 are closed, the third valve 903 and the second valve 902 are opened, and the first working fluid circuit is composed of the compressor 2, the third valve 903, the first heat exchanger 101, the first type of expansion device 301, the second heat exchanger 102, and the second valve 902; the fourth valve 904 and the first valve 901 are opened, the third valve 903 and the second valve 902 are closed, and the second working fluid circuit is composed of the compressor 2, the fourth valve 904, the first heat exchanger 101, the second type of expansion device 302, the second heat exchanger 102, and the first valve 901; when the first type of expansion device 301 is also used for working fluid compression, the second working fluid circuit can also be composed of the first heat exchanger 101, the first type of expansion device 301, the second type of expansion device 302, and the second heat exchanger 102; when the compressor 2 and the first type of expansion device 301 are used for working fluid compression at the same time, the second working fluid circuit can also be composed of the compressor 2, the first type of expansion device 301 , a fourth valve 904, a first heat exchanger 101, a second type of expansion device 302, a second heat exchanger 102, and a first valve 901. In this case, similarly, when there is a direction between the first type of expansion device 301 and the inlet and outlet of the compressor 2, when the compressor 2 and the first type of expansion device 301 are used for working fluid compression at the same time, it is necessary to use a four-way valve or multiple valves to connect the inlet of the first type of expansion 301 and the inlet of the compressor 2 to the outlet of the second heat exchanger 102, and the outlet of the first type of expansion 301 and the outlet of the compressor 2 to the inlet of the first heat exchanger 101. On the other hand, similarly, a valve is provided on the relevant connecting pipeline, and is closed in the second working fluid circuit, but in the first working fluid circuit, the outlet of the compressor 2 and the inlet of the first heat exchanger 101 are connected, and one interface of the second type of expansion device is connected to the connecting pipeline between the outlet of the compressor 2 and the inlet of the first heat exchanger 101, which still satisfies that one interface of the second type of expansion device is connected to the first pipeline and the other interface is connected to the second pipeline.

[0126] It is important to emphasize that: Figure 2 In the embodiment, the first type expansion device 301 is a first type expansion device, and the second type expansion device 302 is a second type expansion device; the valve 9 can have the function of opening or disconnecting the working medium connection at both ends of the valve. It should be further pointed out that, if Figure 2As shown in (h), the first heat exchanger 101 has other interfaces in addition to the inlet and outlet, and the other interfaces are not located at the inlet and outlet on the heat exchanger. When one interface of the second type expansion device is connected to other interfaces of the first heat exchanger 101, in this case, since the first heat exchanger 101 is still located on the first pipeline of the first working fluid circuit, it is still satisfied that one interface of the second type expansion device is connected to the first pipeline and the other interface is connected to the second pipeline. Similarly, when another interface of the second type expansion device is connected to other interfaces on the second heat exchanger 102, in this case, it is also satisfied that one interface of the second type expansion device is connected to the first pipeline and the other interface is connected to the second pipeline.

[0127] The heat pump system also includes a mass regulating device 4. The function of the mass regulating device 4 is to switch the operating cycle of the heat pump system between a vapor compression cycle approaching or completing a Brayton cycle and a Brayton cycle approaching or completing a Brayton cycle by regulating the mass of the working fluid. The mass regulating device 4 includes a working fluid storage tank 5 and a control valve 6. The control valve 6 has the function of controlling the connection and disconnection between the working fluid storage tank 5 and the working fluid in the heat pump system. The working fluid in the heat pump system includes the working fluid inside the heat exchanger, the compressor, and the expansion device. More specifically, the working fluid in the heat pump system refers to the working fluid inside the space connected to the operating compressor, the expansion device, and the heat exchanger that is exchanging heat. The total mass of the working fluid in the heat pump system can be adjusted by pumping the working fluid in the heat pump system into the working fluid storage tank 5 for storage or by releasing the working fluid stored in the working fluid storage tank 5 into the working fluid in the heat pump system. Figure 1 As shown, under the action of the control valve 6, the connection and disconnection between the working medium in the working medium storage tank 5 and the working medium in the heat pump system can be connected or disconnected. The working medium in the heat pump system can be pumped into the working medium storage tank 5 by using the compressor 2 of the heat pump system, for example: the mass regulating device 4 is arranged at the outlet side of the compressor 2; the working medium in the heat pump system can also be pumped into the working medium storage tank 5 by the mass regulating device 4 including a working medium pump 7, for example: Figure 1 A mass regulating device 4 with a working fluid pump 7 is shown. When the control valve 6 connects the working fluid storage tank 5 with the working fluid in the heat pump system, the working fluid in the heat pump system is pumped into the working fluid storage tank 5 under the action of the working fluid pump 7, thereby reducing the total mass of the working fluid in the heat pump system.

[0128] The heat pump system contains at least one working fluid with a critical temperature higher than 300K, such as CO2, Freon, alkanes, etc. and their mixtures. Freon is a general term for chlorofluorocarbons, hydrofluoroolefins, hydrofluorocarbons, etc. This is because in order to achieve or approach the vapor compression cycle when facing cooling or heating needs, the working fluid critical temperature needs to be higher than 300K.

[0129] The heat pump system has two operating modes; the first operating mode is the refrigeration cycle, the heat pump system consumes electricity and generates cold and heat.

[0130] When the heat pump system is operating in the first operating mode, and when the operating temperature difference of the operating working fluid is less than 60°C, the mass regulating device 4 is controlled to regulate the total mass of the operating working fluid in the heat pump system, and to regulate the pressure in the first heat exchanger 101 and the second heat exchanger 102, so as to achieve that the proportion of the mass flow of the liquid working fluid at the inlet and / or outlet of at least one expansion device to the total mass flow of the working fluid is greater than 10%. Since the heat pump system has X ≥ 1 first-class expansion devices and Y ≥ 1 second-class expansion devices, preferably, for non-CO2 working fluids, the inlet and / or outlet of the expansion device is the inlet of the second-class expansion device, and the liquid at the inlet of the second-class expansion device is greater than 10%. The proportion of the mass flow rate of the solid working fluid to the total mass flow rate of the working fluid is 100%. In view of the possible existence of non-condensable gases, the mass flow rate of the liquid working fluid accounts for more than 90% of the total mass flow rate of the working fluid. For the CO2 working fluid, the inlet and / or outlet of the expansion device is the outlet of the second type of expansion device, and the mass flow rate of the liquid working fluid accounts for more than 50% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid in the heat pump system passing through the second type of expansion device accounts for more than 90% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid in the heat pump system passing through the first type of expansion device accounts for less than 10% of the total mass flow rate of the working fluid. Therefore, liquid will be generated in the first heat exchanger 101 and / or the second heat exchanger 102. In order to reduce the damage of the generated liquid droplets to the first type expansion device 301, the mass flow rate of the working fluid in the heat pump system passing through the first type expansion device 301 is controlled to account for less than 10% of the total mass flow rate of the working fluid. Preferably, the mass flow rate of the working fluid in the heat pump system passing through the second type expansion device is controlled to account for 100% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid in the heat pump system passing through the first type expansion device is controlled to account for 0% of the total mass flow rate of the working fluid, thereby eliminating the damage of the liquid to the first type expansion device. Among them: the working temperature difference of the operating working fluid refers to the difference between the average temperature of the heat exchange between the working fluid and the external high-temperature heat source and the average temperature of the heat exchange between the working fluid and the external low-temperature heat source. The average temperature of the heat exchange with the external heat source is theoretically obtained by averaging the amount of heat absorbed or released at each temperature. For the case where there is a phase change process in the heat exchanger for heat exchange with the external heat source, since the heat release or heat absorption mainly occurs in the phase change process, for the sake of simplicity, the phase change temperature will change due to the flow resistance, but the phase change temperature slip is generally small, and it can be calculated by any phase change temperature from the beginning stage of the phase change to the end stage of the phase change, preferably, it is calculated by the phase change temperature corresponding to the midpoint from the beginning stage of the phase change to the end stage of the phase change; for the case where there is no phase change process in the heat exchanger for heat exchange with the external heat source, it can be calculated by the arithmetic average of the working fluid inlet temperature and the outlet temperature of the heat exchanger, that is, (working fluid inlet temperature + working fluid outlet temperature) / 2. In addition, the selection of relevant parameters: <60℃ is mainly for cold or hot needs. For example, for cooling in summer, the evaporation temperature is 5℃, and the ambient temperature is generally within 50℃; for heating in winter, the heating temperature of the terminal equipment can reach 35~45℃, and the heating temperature difference of <60℃ can meet the heating demand of the environment of -15~-10℃.It should be pointed out that, when facing the demand for cooling or heating, the operating temperature difference of the operating fluid may be greater than 60°C. Preferably, in this case, the proportion of the mass flow rate of the liquid working fluid at the inlet of at least one expansion device to the total mass flow rate of the working fluid can still be controlled to be greater than 10%; the mass flow rate of the working fluid in the heat pump system passing through the second type of expansion device can be controlled to be greater than 90% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid in the heat pump system passing through the first type of expansion device can be controlled to be less than 10% of the total mass flow rate of the working fluid. In addition, it should be emphasized that the total mass flow rate of the working fluid in the proportion of the mass flow rate of the liquid working fluid at the inlet of the expansion device to the total mass flow rate of the working fluid refers to the total mass of the working fluid passing through the expansion device. When there are multiple expansion devices running at the same time, the proportion of the mass flow rate of the liquid working fluid at the inlet of at least one expansion device to the total mass flow rate of the working fluid passing through the expansion device meets the above requirements.

[0131] The second operating mode is a power cycle, in which the heat pump system consumes cold and heat to generate electricity. When the heat pump system operates in the second operating mode and the operating temperature difference of the operating working fluid is >100°C, the control mass adjustment device 4 adjusts the total mass of the operating working fluid in the heat pump system, and adjusts the pressure in the first heat exchanger 101 and the second heat exchanger 102 to achieve that the proportion of the mass flow of the liquid working fluid at the inlet of at least one expansion device to the total mass flow of the working fluid is ≤10%. This is because if liquid is generated in the second operating mode, it will cause related irreversible losses in the heat transfer process or increase the difficulty of storing cold and heat. Preferably, the inlet of the expansion device is the inlet of the first type of expansion device, and the proportion of the mass flow of the liquid working fluid at the inlet of the first type of expansion device to the total mass flow of the working fluid is 0. ; The proportion of the mass flow of the working fluid in the heat pump system passing through the second type of expansion device to the total mass flow of the working fluid is controlled to be less than 10%, and the proportion of the mass flow of the working fluid in the heat pump system passing through the first type of expansion device to the total mass flow of the working fluid is controlled to be greater than 90%. This is because the second type of expansion device cannot recover the expansion work and output mechanical work, which leads to a decrease in the power generation of the heat pump system when it is running in the second operation mode. Preferably, the proportion of the mass flow of the working fluid in the heat pump system passing through the second type of expansion device to the total mass flow of the working fluid is controlled to be 0, and the proportion of the mass flow of the working fluid in the heat pump system passing through the first type of expansion device to the total mass flow of the working fluid is controlled to be 100%. The above process can be achieved by controlling the mass adjustment device 4 to adjust the total mass of the working fluid in the heat pump system. When the mass of the working fluid in the system is less than the mass corresponding to the saturated steam at the average temperature of the system, at this time, there is no liquid in the system; on the contrary, when the mass of the working fluid in the system is greater than the mass corresponding to the saturated steam at the average temperature of the system, at this time, the excess working fluid exists in the form of liquid.

[0132] Since the second operation mode uses cold and heat to produce electricity, and the cold and heat for producing electricity come from the first operation mode, Figure 3As shown, when the heat pump system operates in the first operating mode and when facing the power storage demand, the operating working fluid working temperature difference is basically the same as the operating working fluid working temperature difference in the second operating mode, that is, when the operating working fluid working temperature difference is greater than 100°C, the control mass regulating device 4 regulates the total mass of the operating working fluid in the heat pump system, and regulates the pressure in the first heat exchanger 101 and the second heat exchanger 102, so as to achieve that the proportion of the liquid working fluid mass flow rate in the total working fluid mass flow rate at at least one expansion device inlet is ≤10%. Preferably, the expansion device inlet is a first type expansion device inlet, and the first type expansion device The proportion of the mass flow rate of the liquid working fluid at the inlet to the total mass flow rate of the working fluid is 0; the proportion of the mass flow rate of the working fluid in the heat pump system passing through the second type of expansion device to the total mass flow rate of the working fluid is controlled to be less than 10%, and the proportion of the mass flow rate of the working fluid in the heat pump system passing through the first type of expansion device to the total mass flow rate of the working fluid is controlled to be greater than 90%. Preferably, the proportion of the mass flow rate of the working fluid in the heat pump system passing through the second type of expansion device to the total mass flow rate of the working fluid is controlled to be 0, and the proportion of the mass flow rate of the working fluid in the heat pump system passing through the first type of expansion device to the total mass flow rate of the working fluid is controlled to be 100%. In addition, the selection of relevant parameters: >100℃ is mainly for power storage needs. Under a certain heat storage and cold storage volume, the greater the temperature difference between hot and cold, the higher the power storage density can be achieved. Preferably, the temperature difference between the average temperature in the first heat exchanger and the average temperature in the second heat exchanger is suitable between 150 and 550℃.

[0133] When operating in the first operating mode and the operating working fluid working temperature difference is less than 60°C, the operating working fluid is controlled to operate in the second working fluid circuit; when operating in the first operating mode and the operating working fluid working temperature difference is greater than 100°C, the operating working fluid is controlled to operate in the first working fluid circuit; when operating in the second operating mode and the operating working fluid working temperature difference is greater than 100°C, the operating working fluid is controlled to operate in the first working fluid circuit. When the operating working fluid operates in both the second working fluid circuit and the first working fluid circuit, if the mass flow rate through the second type expansion device in the second working fluid circuit accounts for less than 20% of the total mass flow rate, it is still considered to be operating in the first working fluid circuit; otherwise, it is considered to be operating in the second working fluid circuit, and the total working fluid mass flow rate is equal to the sum of the mass flow rate through the second type expansion device in the second working fluid circuit and the mass flow rate through the first type expansion device in the first working fluid circuit.

[0134] When operating in the first operating mode and the working temperature difference of the operating medium is less than 60°C, the first type expansion device X≥1 is controlled to stop being used for the expansion of the working medium. In this case, the first type expansion device can still be used for the compression of the working medium. This is because in this case, there may be liquid in the working medium entering the first type expansion device. In order to avoid the damage of the liquid to the first type expansion device, at least one first type expansion device is controlled to stop being used for the expansion of the working medium. Preferably, all first type expansion devices are stopped for the expansion of the working medium. When operating in the first operating mode and the working temperature difference of the operating medium is greater than 100°C, the second type expansion device Y≥1 is controlled to stop being used for the expansion of the working medium; when operating in the second operating mode and the working temperature difference of the operating medium is greater than 100°C, the second type expansion device Y≥1 is controlled to stop being used for the expansion of the working medium. In this case, the heat pump is mainly aimed at the demand for power storage, and the working temperature difference of the working medium is large. In order to improve efficiency, it is necessary to avoid using an expansion device that cannot recover expansion work. Therefore, at least one second type expansion device is controlled to stop being used for the expansion of the working medium. Preferably, all second type expansion devices are stopped for the expansion of the working medium. When the expansion device has an unloading operating mechanism, it can be judged according to the state of the unloading operating mechanism; when there is no unloading operating mechanism and a working fluid flow passes through the expansion device in addition to leakage, the first type of expansion device stops being used for working fluid expansion, which can be judged according to whether the expansion device is running and whether there is working fluid passing through the expansion device. For example: the first type of expansion device should be considered to be stopped when the speed is less than the compressor speed or 20% of the rated speed of the first type of expansion device; the second type of expansion device stops being used for working fluid expansion, which can be judged according to the opening of the second type of expansion device. The second type of expansion device is considered to have stopped being used for working fluid expansion when the opening is less than 10% of its maximum opening.

[0135] The expansion device of the heat pump system has an unloading operation mechanism, which is used to reduce or eliminate additional leakage losses or friction losses when the expansion device is not used for working fluid expansion. The unloading operation mechanism is a valve and / or a clutch, etc. The valve can be a solenoid valve or a hydraulic valve, etc. When the expansion device is not used for working fluid expansion, for example: when the heat pump system is operating in the second mode, it is necessary to control the proportion of the working fluid mass flow rate passing through the second type of expansion device to less than 10% of the total working fluid mass flow rate, preferably 0. However, the second type of expansion device may have its own leakage in the closed operating state, thereby generating leakage losses. A valve may be provided at the inlet or outlet of the expansion device. When the expansion device is not operating, the valve at the inlet or outlet of the expansion device is closed to avoid leakage losses when the relevant expansion device is not used for working fluid expansion during the operation of the heat pump. In addition, for the first type of expansion device, since it can directly output mechanical work, the output shaft of the first type of expansion device is connected to the motor in order to eliminate the additional friction losses generated by idling during the period when the first type of expansion device is not used for working fluid expansion. Figure 1As shown, a clutch 13 can be provided between the first type of expansion device 301 and the motor 12. When the heat pump system adopts the second type of expansion device 302 for working fluid expansion and the first type of expansion device 301 is not used for working fluid expansion or compression, the connection between the first type of expansion device 301 and the motor 12 is disconnected through the clutch 13. When the motor is running, the first type of expansion device 301 is in a stationary state to avoid friction loss. When the heat pump system adopts the first type of expansion device 301 for working fluid expansion or compression, an axial connection is generated between the first type of expansion device 301 and the motor 12 through the clutch 13.

[0136] The heat pump system also includes a first heat storage device 801 and a second heat storage device 802. The heat exchange between the heat storage device and the working medium can be any of the following: the heat transfer medium from the heat storage device flows into the heat storage device after the heat exchange with the working medium is completed in the first heat exchanger 101 or the second heat exchanger 102; and / or, the heat storage device and the heat exchanger are connected in parallel, and the working medium directly exchanges heat with the heat storage material inside the heat storage device. Figure 1 As shown, the heat transfer medium from the first heat storage device 801 exchanges heat with the working fluid in the first heat exchanger 101, and then the heat transfer medium flows into the first heat storage device 801. In order to meet the cooling and heating needs, a sixth heat exchanger 106 is also included. The heat transfer medium transfers heat to the heating object through the sixth heat exchanger 106. Under this structure, when meeting the cooling or heating needs, the heat exchange between the heat transfer medium and the first heat storage device 801 is closed by setting a relevant valve on the pipeline, and the heat transfer medium exchanges heat between the first heat exchanger 101 and the sixth heat exchanger 106; when meeting the power storage needs, the heat exchange between the heat transfer medium and the sixth heat exchanger 106 is closed by setting a relevant valve on the pipeline, and the heat transfer medium exchanges heat between the first heat exchanger 101 and the first heat storage device 801; similarly, the second heat storage device 802 can also adopt a heat exchange with a similar structure. Figure 1 A heat storage device and a heat exchanger parallel structure is also shown. The second heat storage device 802 is connected in parallel with the second heat exchanger 102. The second heat storage device 102 has a heat storage material inside. The heat storage material is a solid medium such as rock and steel ball. When facing the cold or hot demand, the heat exchange between the working medium and the second heat storage device 802 is closed by setting a relevant valve on the pipeline, and the working medium transfers the cold to the cooled object through the second heat exchanger 802; when facing the power storage demand, the heat exchange between the working medium and the second heat exchanger 102 is closed by setting a relevant valve on the pipeline, and the working medium exchanges heat with the heat storage material in the second heat storage device 802; similarly, the first heat storage device 801 can also adopt a heat exchange with a similar structure. In addition, it can also be a mixed combination of the above schemes. Preferably, the heat transfer medium is a liquid such as an aqueous solution or thermal oil.

[0137] For some types of expanders, such as volumetric expanders, they are not only highly efficient in working fluid expansion, but also highly efficient in working fluid compression. Therefore, when the heat pump system is operating in the first operating mode, when the heat pump system is facing cold / heating demand, or when the operating working fluid working temperature difference is less than 60°C, the working fluid expansion of the heat pump system is completed based on the second type of expansion device, and the first type of expansion device is not suitable for working fluid expansion under this application. In this case, the first type of expansion device can be used for the working fluid compression function in the second working fluid circuit under the action of the valve, thereby reducing the volume and cost of the compressor when facing cold or hot demand. When the first type of expansion device is used for the working fluid compression function, it includes the following situations: the working fluid is all compressed in the first type of expansion device; part of the working fluid is compressed in the first type of expansion device and the other part is compressed in compressor 2; the first type of expansion device is connected in series with compressor 2, flows into the first type of expansion device for pre-compression, and then flows into compressor 2 for secondary compression; the first type of expansion device is connected in series with the compressor, flows into compressor 2 for pre-compression, and then flows into the first type of expansion device for secondary compression. The above functions can all be realized in the same heat pump system. Figure 4 The schematic diagrams of several expanders used for compressing working fluid under the action of valves are shown. Figure 4 (a) shows the parallel operation of the expander and the compressor. The first type of expansion device 301 is a first type of expansion device, i.e., an expander. When used for expansion, the first type of expansion device 301 is an expander. When used for expansion, the first valve 901 and the second valve 902 are closed, the third valve 903 and the fourth valve 904 are opened, and the working medium passes through the second heat exchanger 102, the compressor 2, the first heat exchanger 101, and the first type of expansion device 301 in sequence; when the first type of expansion device 301 is used for compression, the third valve 904 and the fourth valve 904 are closed, the first valve 901 and the second valve 902 are opened, and the working medium passes through the second heat exchanger 102, the compressor 2, the first heat exchanger 101, and the first type of expansion device 301 in sequence. 902 is opened, and part of the working fluid flowing out of the second heat exchanger 102 flows into the first heat exchanger 101 through the compressor 2, and part of it flows into the first heat exchanger 101 through the second valve 902, the first type of expansion device 301, and the first valve 901. After heat exchange in the first heat exchanger 101, the working fluid flows into the second heat exchanger 102 through the second type of expansion device 302. Therefore, at this time, the expander and the compressor are connected in parallel to play a compression function. When the compressor 2 is closed, only the first type of expansion device 301 is used for compression, and the working fluid flowing out of the second heat exchanger 102 all flows into the first type of expansion device 301. Figure 4(b) shows the serial operation. The first type of expansion device 301 is an expander. When it is used for expansion, the second valve 902 and the sixth valve 906 are closed, the third valve 903, the fourth valve 904, and the fifth valve 905 are opened, and the working medium passes through the second heat exchanger 102, the fifth valve 905, the compressor 2, the first heat exchanger 101, the fourth valve 904, the first type of expansion device 301, and the third valve 903 in sequence; when the first type of expansion device 301 is used for compression, the second valve 902 and the sixth valve 906 are opened, the third valve 903, the fourth valve 904, and the fifth valve 905 are closed, and the working medium flowing out of the second heat exchanger 102 flows into the compressor 2 through the second valve 902, the first type of expansion device 301, and the sixth valve 906. After heat exchange in the first heat exchanger 101, the working medium flows into the second heat exchanger 102 through the second type of expansion device 302. Therefore, at this time, the expander and the compressor are connected in series, serving as the front stage compression of the compressor. Figure 4 (c) in the figure shows another serial operation situation, where the first type expansion device 301 is an expander. When used for expansion, the ninth valve 909 and the seventh valve 907 are closed, the third valve 903, the fourth valve 904, and the eighth valve 908 are opened, and the working medium passes through the second heat exchanger 102, the compressor 2, the eighth valve 908, the first heat exchanger 101, the fourth valve 904, the first type expansion device 301, and the third valve 903 in sequence; when the first type expansion device 301 is used for second-stage compression, the ninth valve 909 and the seventh valve 907 are opened, the third valve 903, the fourth valve 904, and the eighth valve 908 are closed, and the working medium flowing out of the second heat exchanger 102 flows into the compressor 2. After being compressed in the compressor, the working medium passes through the seventh valve 907, the first type expansion device 301, and the ninth valve 909 in sequence. After heat exchange in the first heat exchanger 101, the working medium flows into the second heat exchanger 102 through the second type expansion device 302. Therefore, at this time, the expander and the compressor are connected in series, serving as the latter stage compression of the compressor. In addition, the first to ninth valves are installed on a system according to the above schematic diagram, such as Figure 8 As shown in (d) in FIG. 1 , the above-mentioned operation of the expander and the compressor can be realized on a heat pump system. Figure 4 All the functions shown in (a), (b), and (c), namely, parallel and series functions, are not repeated here. Preferably, the structural scheme of the expander for compressing the working fluid under the action of the valve is a parallel scheme of the expander and the compressor.

[0138] The heat pump system compressor is composed of N≥2 compression modules and a compression module control valve 14. The number of compression modules can be configured according to the cooling or heating capacity of the unit. Usually, the number is less than 100, preferably 8 or 16. Under the action of the compression module control valve 14, the first type of expansion device is ≥1 compression module of the compressor 2, that is, ≥1 compression module is used to recover the expansion work of the working fluid expansion process and output mechanical work. When operating in the first operating mode and the working temperature difference of the working fluid is greater than 100°C, under the action of the compression module control valve, K≥1 compression modules are used for working fluid compression, J≥1 compression modules are used for working fluid expansion, K+J≤N; when operating in the second operating mode and the working temperature difference of the working fluid is greater than 100°C, K≥1 compression modules are used for working fluid compression, J≥1 compression modules are used for working fluid expansion, K+J≤N.

[0139] Figure 5 A heat pump system is shown in which the first type of expansion device is a compression module. The heat pump system is composed of two compression modules and a compression module control valve 14. When the first compression module 2001 and the second compression module 2002 are used for working fluid compression, the third compression module control valve 1403 and the fourth compression module control valve 1404 are opened, and the first compression module control valve 1401 and the second compression module control valve 1402 are closed. The working fluid from the second heat exchanger 102 is compressed in the first compression module 2001 and the second compression module 2002, and then flows into the first heat exchanger 101, expands in the first type of expansion device 301 or the second type of expansion device 302, and then flows into the second heat exchanger 102. When the second compression module 2002 is used for working fluid expansion, the third compression module control valve 1403 and the fourth compression module control valve 1404 are closed, the first compression module control valve 1401 and the second compression module control valve 1402 are opened, and the working fluid from the second heat exchanger 102 is compressed in the first compression module 2001, then flows into the first heat exchanger 101, flows into the second compression module 2002 through the first compression module control valve 1401 and expands in the second compression module 2002, and then flows into the second heat exchanger 102 through the second compression module control valve 1402.

[0140] Since turbine machinery has poor efficiency under low power and variable operating conditions, while positive displacement compressors and expanders have good efficiency under low power and variable operating conditions, preferably, the compressor and expander of the multi-purpose heat pump system for cooling or heating and electricity storage needs are positive displacement compression or expansion equipment, and the compressor of the heat pump system is a positive displacement compressor with ≥1 air valve, which may be an intake valve or an exhaust valve, at least one of which is actively controlled, and the opening and closing of the active control valve is controlled by electromagnetic force, hydraulic pressure or mechanical force, etc. Preferably, the compressor has both an intake valve and an exhaust valve, and both the intake valve and the exhaust valve are actively controlled valves; and / or, the first type of expansion device has ≥1 air valve, which may be an intake valve or an exhaust valve, at least one of which is actively controlled, and the opening and closing of the active control valve is controlled by electromagnetic force, hydraulic pressure or mechanical force, etc. Preferably, the first type of expansion device has both an intake valve and an exhaust valve, and both the intake valve and the exhaust valve are actively controlled valves. The number of valves is ≥ 1 because: for some types of compressors, the number of valves is 1, for example, a scroll compressor, which usually has only an exhaust valve; for some types of compressors, the number of valves is 2, for example, a piston compressor. Similarly, the same situation exists for the first type of expansion device.

[0141] When the heat pump system is running in the second mode, the mass regulating device 4 is controlled to regulate the total mass of the working fluid in the heat pump system, and the minimum operating pressure in the heat pump system is controlled to be less than the saturated pressure of the working fluid at 0°C. Since the heat pump system is running in the second mode, in order to achieve a larger heat absorption, the minimum temperature in the second heat exchanger may reach about 200K. Therefore, preferably, the minimum operating pressure in the heat pump system is controlled to be less than the saturated pressure of the working fluid at 230K. For example, for CO2 working fluid, its saturated pressure at 230K is 0.89291MPa, and the heat pump system is controlled to be less than the saturated pressure of the working fluid at 230K. The minimum operating pressure in the pump system is <0.89291MPa. For example, when the minimum pressure is 0.5MPa, when the minimum temperature is 230K, CO2 will not be liquefied; and / or, when the heat pump system is operating in the second operating mode, the mass adjustment device 4 is controlled to adjust the total mass of the operating working fluid in the heat pump system, and the minimum operating pressure in the heat pump system is controlled to achieve that the proportion of the liquid working fluid mass flow in the first heat exchanger and / or the second heat exchanger to the total working fluid mass flow is ≤1%, preferably 0, thereby reducing the impact of liquid phase change on the efficiency during the second mode of operation.

[0142] Due to the different requirements for working fluids for cooling or heating and electricity storage needs, for example: cooling or heating needs require the working fluid to have a phase change in the room temperature range, so that the refrigeration efficiency is high and the refrigeration capacity is large; the electricity storage needs require the working fluid to have a large adiabatic index, so that the unit working fluid releases or absorbs large amounts of heat and the unit volume electricity storage density is high. Therefore, when the working fluid with a critical temperature higher than 300K is used for electricity storage, there are problems such as low efficiency and low electricity storage density. The heat pump system further includes a working fluid with a critical temperature lower than 300K. When operating in the first operating mode and when the operating temperature difference of the operating working fluid is less than 60°C, the mass regulating device 4 is used to control the mass flow rate of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to account for more than 50% of the total working fluid mass flow rate, and the mass flow rate of the working fluid with a critical temperature lower than 300K to account for less than 50% of the total working fluid mass flow rate. Preferably, the mass flow rate of the working fluid with a critical temperature higher than 300K accounts for ≥99% of the total working fluid mass flow rate, and the mass flow rate of the working fluid with a critical temperature lower than 300K accounts for less than 1% of the total working fluid mass flow rate. When operating in the first operating mode, and when the operating working fluid operating temperature difference is greater than 100°C, the mass regulating device 4 is used to control the mass flow rate of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to be less than 50% of the total working fluid mass flow rate, and the mass flow rate of the working fluid with a critical temperature lower than 300K to be greater than 50% of the total working fluid mass flow rate. Preferably, the mass flow rate of the working fluid with a critical temperature higher than 300K to be less than 1% of the total working fluid mass flow rate, and the mass flow rate of the working fluid with a critical temperature lower than 300K to be greater than 99% of the total working fluid mass flow rate. When operating in the second operating mode, and when the operating temperature difference of the operating medium is greater than 100°C, the mass regulating device 4 is used to control the mass flow rate of the working medium with a critical temperature higher than 300K in the circulating working medium flow rate of the cold, heat and electricity multi-purpose heat pump system to be less than 50% of the total working medium mass flow rate, and the mass flow rate of the working medium with a critical temperature lower than 300K to be greater than 50% of the total working medium mass flow rate. Preferably, the mass flow rate of the working medium with a critical temperature higher than 300K to be less than 1% of the total working medium mass flow rate, and the mass flow rate of the working medium with a critical temperature lower than 300K to be greater than 99% of the total working medium mass flow rate. This is because when the temperature difference is small in the first mode, the working medium with a critical temperature lower than 300K may not undergo phase change. Therefore, a large amount of working medium with a critical temperature lower than 300K in the heat pump system will increase the heat transfer resistance and reduce the performance of the heat pump system; when the temperature difference is large in the first mode, this working condition is oriented to the demand for power storage, and the working medium with a critical temperature higher than 300K may undergo phase change, thereby reducing the heat storage and cold storage efficiency, thereby reducing the power storage efficiency. Preferably, the working fluid with a critical temperature lower than 300K may be helium, hydrogen, argon, nitrogen, oxygen, air, etc.The number of mass regulating devices 4 is ≥ 2, wherein at least one mass regulating device 4 is used for mass regulating, including storage and release, at least one working fluid with a critical temperature higher than 300K; wherein at least one mass regulating device 4 is used for mass regulating, including storage and release, a working fluid with a critical temperature lower than 300K. When the working fluid with a critical temperature lower than 300K is a gas such as air, nitrogen, oxygen, etc. that can be obtained from the environment, the number of mass regulating devices 4 can be one, which is mainly used to store and regulate the working fluid with a critical temperature higher than 300K. In addition, when there is a cold source inside the mass regulating device 4, the number of mass regulating devices 4 can also be one, that is, using an external cold source to condense the critical temperature higher than 300K into a liquid to achieve gas separation inside the mass regulating device 4. At this time, the mass regulating device 4 is a gas separator with a valve.

[0143] Figure 6A multi-purpose heat pump system for heat, cold and electricity with working fluids having critical temperatures below 300K and above 300K is shown. The heat pump system has a first mass regulating device 401 and a second mass regulating device 402. Under the action of the first mass regulating device 401, the working fluid with a critical temperature above 300K in the heat pump system is pumped into the working fluid storage tank 5, and then, under the action of the second mass regulating device 402, the working fluid with a critical temperature below 300K stored in the working fluid storage tank of the second mass regulating device 402 is released into the heat pump system. Similarly, under the action of the second mass regulating device 402, the working fluid with a critical temperature below 300K can be pumped into the working fluid storage tank 5, and then, under the action of the first mass regulating device 401, the working fluid with a critical temperature above 300K stored in the working fluid storage tank of the first mass regulating device 401 is released into the heat pump system, thereby realizing automatic switching of the operating working fluid in the heat pump system. When the working fluid with a critical temperature lower than 300K can be obtained from the atmosphere, it can also be as follows: under the action of the first mass regulating device 401, the heat pump system pumps the working fluid with a critical temperature higher than 300K in the heat pump system into the working fluid storage tank 5, and then pumps the ambient atmosphere into the heat pump system; similarly, the ambient atmosphere is pumped out of the heat pump system, and the working fluid with a critical temperature higher than 300K stored in the working fluid storage tank 5 of the first mass regulating device 401 is pumped into the heat pump system. Since it may be difficult for the heat pump system to completely pump the working fluids with different critical temperatures into the working fluid storage tank during the above-mentioned working fluid switching process, which leads to mixing of the working fluids and makes it very difficult to completely operate the second working fluid or the first working fluid, the heat pump system also includes a gas separator 15, which can be arranged at the outlet of the heat exchanger or in the working fluid storage tank. For example, when the critical temperature is higher than 300K, the working fluid undergoes a phase change, the first working fluid in the first heat exchanger 101 is liquid, and the working fluid with a critical temperature lower than 300K is still in a gaseous state. The working fluid separator 15 can be used to separate the two working fluids with different critical temperatures under the action of gravity, and then in the first heat exchanger 101, the working fluids with different critical temperatures can be separated. Under the action of a gas separation control valve 1601 and a working fluid pump 7, the working fluid with a critical temperature lower than 300K is pumped into the working fluid storage tank 5 of the second mass regulating device 402; when the working fluid with a critical temperature higher than 300K enters the working fluid storage tank 5 of the second mass regulating device 402, the working fluid with a critical temperature higher than 300K can be condensed into liquid by a condensation method, for example, an independent refrigeration device or a heat pump system can be used for reference. Similarly, gravity can be used to deliver the liquid working fluid with a critical temperature higher than 300K to the working fluid storage tank 5 of the first mass regulating device 402 through the connecting pipe at the bottom of the working fluid 5 and the second gas separation control valve 1602. In addition, a related adsorption separation device can be set at the outlet of the working fluid storage tank 5 to further purify the working fluid entering the heat pump system.

[0144] The heat pump system also includes a regenerator, which has a first flow channel and a second flow channel. One end of the first flow channel of the regenerator is connected to the outlet end of the first heat exchanger, and the other end is connected to the inlet end of the first type expansion device. One end of the second flow channel of the regenerator is connected to the outlet end of the second heat exchanger, and the other end is connected to the compressor. Figure 7 As shown, the heat pump system has a regenerator 10. When the heat pump system operates in the first working medium loop, the working medium passes through the compressor 2, the first heat exchanger 101, the first flow channel of the regenerator 10, the first type expansion device 301, the second heat exchanger 102, and the second flow channel of the regenerator 10. The heat pump system is oriented to cold or hot demand. The heat pump system can use a regenerator or not. Since the use of a regenerator for some working medium will reduce the performance, Figure 7 It shows the situation where no regenerator is used for cooling or heating demand, and the working medium passes through the compressor 2, the third heat exchanger 103, the second type expansion device 302, and the fourth heat exchanger 104.

[0145] When the first type of expansion device cannot be used for working fluid compression, such as when the first type of expansion device is a turbine expander, since the turbine expander has a low efficiency problem when used for compression, when charging, that is, when operating in the first operating mode, and when the working temperature difference of the operating working fluid is greater than 100°C, a compressor is required for working fluid compression; when discharging, that is, when operating in the second operating mode, and when the working temperature difference of the operating working fluid is greater than 100°C, a compressor is also required for working fluid compression, but the requirements for compressors under the two working conditions are different, so the number of compressors required is ≥ 2, wherein: when operating in the first operating mode, and when the working temperature difference of the operating working fluid is greater than 100°C, the compressor used for working fluid compression is the first compressor 201, and when operating in the second operating mode, and when the working temperature difference of the operating working fluid is greater than 100°C, the compressor used for working fluid compression is the second compressor 202. Preferably, the second compressor 202 has a smaller gas output than the first compressor 201 under the same frequency and intake parameters. Therefore, when the heat pump system is facing cooling / heating demand, since the working fluid expansion of the heat pump system is completed based on the second type of expansion device, at this time, the second compressor 202 can be used for the working fluid compression function in the second working fluid circuit under the action of the valve, thereby reducing the volume and cost of the compressor when facing cooling or heating demand. Therefore, when operating in the first operating mode and when the operating working fluid working temperature difference is less than 60°C, the second compressor 202 is used for compressing the working fluid in the second working fluid circuit, including any of the following situations: the working fluid is all compressed in the second compressor 202, and the working fluid is expanded through the second type of expansion device; and / or, one of the working fluids Part of the working fluid is compressed in the second compressor 202, and the other part is compressed in the first compressor 201, and the working fluid is expanded through the second type of expansion device; and / or, the first compressor 201 is connected in series with the second compressor 202, the working fluid flows into the second compressor 202 for pre-compression and flows into the first compressor 201 for a second compression, and the working fluid is expanded through the second type of expansion device; and / or, the first compressor 201 is connected in series with the second compressor 202, the working fluid flows into the first compressor 201 for pre-compression and flows into the second compressor 202 for a second compression, and the working fluid is expanded through the second type of expansion device. The above functions can all be realized in the same heat pump system. Figure 8 Several schematic diagrams of the operation of the second compressor 202 for compressing the working medium in the second working medium circuit under the action of the valve are shown. Figure 8(a) in the figure shows the parallel operation of the first compressor 201 and the second compressor 202. The first compressor 201 can be used as a compressor for compressing the working fluid or as an expander for expanding the working fluid. During charging, the working fluid passes through the first compressor 201, the first heat exchanger 101, the first type of expansion device 301 and the second heat exchanger 102 in sequence. During discharging, since the first type of expansion device 301 cannot be used for working fluid compression, a second compressor 202 is provided, the third valve 904 and the fourth valve 904 are opened, the first valve 901 and the second valve 902 are closed, and the working fluid is compressed in the second compressor 202 and expanded in the first compressor 201. In the second working fluid circuit, the third valve 904 and the fourth valve 904 are opened, the first valve 901 and the second valve 902 are closed, and the working fluid is compressed in the second compressor 202 and expanded in the first compressor 201. The door 904 and the fourth valve 904 are closed, and the first valve 901 and the second valve 902 are opened. A part of the working fluid flowing out of the second heat exchanger 102 is compressed by the first compressor 201 and then flows into the first heat exchanger 101, and a part of the working fluid is compressed by the second valve 902 and the second compressor 202 and then flows into the first heat exchanger 101 through the first valve 901. After heat exchange in the first heat exchanger 101, the working fluid flows into the second heat exchanger 102 through the second type expansion device 302. Therefore, at this time, the expander and the compressor are connected in parallel to play a compression function. When the first compressor 201 is closed, only the second compressor 202 is used for compression, and all the working fluid flowing out of the second heat exchanger 102 flows into the second compressor 202. Figure 8 (b) in the figure shows the serial operation. During discharge, since the first type expansion device 301 cannot be used for working medium compression, a second compressor 202 is provided, the second valve 902 and the sixth valve 906 are closed, the third valve 903, the fourth valve 904, and the fifth valve 905 are opened, and the working medium is compressed in the second compressor 202 and expanded in the first compressor 201; in the second working medium circuit, the second valve 902 and the sixth valve 906 are opened, the third valve 903, the fourth valve 904, and the fifth valve 905 are closed, and the working medium flowing out of the second heat exchanger 102 flows into the first compressor 201 through the second valve 902, the second compressor 202, and the sixth valve 906. After heat exchange in the first heat exchanger 101, the working medium flows into the second heat exchanger 102 through the second type expansion device 302. Therefore, at this time, the second compressor 202 is connected in series with the second compressor 202 as the front stage compression of the compressor. Figure 8(c) in the figure shows another series operation situation. During discharge, since the first type expansion device 301 cannot be used for working medium compression, a second compressor 202 is equipped, the ninth valve 909 and the seventh valve 907 are closed, the third valve 903, the fourth valve 904, and the eighth valve 908 are opened, and the working medium is compressed in the second compressor 202 and expanded in the first compressor 201; when the second compressor 202 is used for second-stage compression, the ninth valve 909 and the seventh valve 907 are opened, the third valve 903, the fourth valve 904, and the eighth valve 908 are closed, and the working medium flowing out of the second heat exchanger 102 flows into the first compressor 201. After being compressed in the first compressor 201, the working medium passes through the seventh valve 907, the second compressor 202, and the ninth valve 909 in sequence. After heat exchange in the first heat exchanger 101, the working medium flows into the second heat exchanger 102 through the second type expansion device 302. Therefore, at this time, the expander and the compressor are connected in series as the latter stage compression of the compressor. In addition, the first to ninth valves are installed on a system according to the above schematic diagram, such as Figure 8 As shown in (d) in FIG. 1 , the heat pump system can realize the above-mentioned operation of the second compressor 202 and the first compressor 201 on a set of heat pump systems. Figure 8 The functions shown in (a), (b), and (c) in the figure are as follows. Preferably, the second compressor 202 is used for compressing the working medium under the action of the valve. The second compressor 202 is connected in parallel with the first compressor 201. It should be noted that Figure 8 In the embodiment, when the second operation mode is in operation and the working temperature difference of the working fluid is greater than 100°C, the compressor used for working fluid compression is the second compressor 202, and the first compressor 201 is used for working fluid expansion and recovery of expansion work. In fact, when the first compressor 201 is a turbine machine, there is also the problem of low expansion efficiency. Therefore, an additional first-class expansion device needs to be configured. In this case, Fig. 9 As shown, two compressors and two expanders are required. The two compressors can also realize the parallel and series functions as described above by setting relevant valves, which will not be repeated here. In addition, Fig. 9 In the figure, the second compressor 202 is connected in parallel with the first first-class expansion device 3010. In fact, the second compressor 202 can also be connected in parallel with the first compressor 201. At this time, the second first-class expansion device 3011 is connected in parallel with the first first-class expansion device 3010. Similarly, the two compressors can also achieve the parallel and series functions as described above by setting relevant valves, which will not be repeated here.

[0146] In the above process, in order to achieve that the mass flow rate of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 accounts for more than 10% of the total mass flow rate of the working fluid, the following schemes are provided through the mass regulating device 4: (1) The heat pump system has only a single working fluid with a critical temperature higher than 300K, such as CO2, R32, etc. Due to the demand for cooling or heating, the lowest temperature in the first heat exchanger 101 and / or the second heat exchanger 102 is lower than the critical temperature of 300K, thereby improving the quality of the working fluid in the heat pump system, and achieving that the mass flow rate of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 accounts for more than 10% of the total mass flow rate of the working fluid; (2) The heat pump system has multiple working fluids with a critical temperature higher than 300K, such as CO2+R32, and the mass regulating device 4 can be used to control the heat pump system. The CO2 working fluid in the heat pump system is pumped out of the heat pump system, and the R32 working fluid is pumped into the heat pump system, and the quality of the R32 working fluid in the heat pump system can achieve a ratio of the mass flow of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 to the total mass flow of the working fluid>10%; (3) the heat pump system has a working fluid with a critical temperature higher than 300K and a working fluid with a critical temperature lower than 300K, such as R32+argon, and the quality regulating device 4 can be used to control the working fluid with a critical temperature lower than 300K, such as argon, to be pumped out of the heat pump system, and the working fluid with a critical temperature higher than 300K, such as R32, to be pumped into the heat pump system, and the quality of the R32 working fluid in the heat pump system can achieve a ratio of the mass flow of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 to the total mass flow of the working fluid>10%.

[0147] In the above process, in order to achieve that the proportion of the mass flow of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 to the total mass flow of the working fluid is less than 10%, the following schemes are provided through the mass regulating device 4: (1) The heat pump system has only a single working fluid with a critical temperature higher than 300K, such as CO2, R32, etc. Due to the demand for power storage, the lowest temperature in the first heat exchanger 101 and / or the second heat exchanger 102 is lower than the critical temperature of 300K. Therefore, in order to reduce the specific gravity of the liquid or eliminate the liquid, it is necessary to reduce the mass of the working fluid in the heat pump system. For example, for CO2, the parameters before expansion are 1.5MPa and 300K. After isentropic expansion to 0.6MPa, the working fluid temperature is 240.66K. Since the saturation temperature corresponding to 0.6MPa is 220.03K, no liquid will be generated after expansion; (2) The heat pump system has multiple working fluids with critical temperatures higher than 300K, such as CO2+R32. The mass regulating device 4 can be used to control the R32 working fluid in the heat pump system to be pumped out of the heat pump system and the CO2 working fluid to be pumped into the heat pump system. The mass of the CO2 working fluid in the heat pump system can achieve a ratio of the mass flow of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 to the total mass flow of the working fluid <10%; (3) The heat pump system has a working fluid with a critical temperature higher than 300K and a working fluid with a critical temperature lower than 300K, such as R32+argon. The mass regulating device 4 can be used to control the working fluid with a critical temperature higher than 300K, such as R32, to be pumped out of the heat pump system and the working fluid with a critical temperature lower than 300K, such as argon, to be pumped into the heat pump system. Argon has a low critical temperature and will not be liquefied under specific operating parameters.

[0148] The heat pump system further includes a third heat exchanger 103 and / or a fourth heat exchanger 104. Figure 2 (a) Figure 2 (f) shows a heat pump system that includes both a third heat exchanger 103 and a fourth heat exchanger 104, wherein the third heat exchanger 103 is located in the connecting pipeline between the outlet of the compressor 2 and the inlet of the second type expansion device 302; the fourth heat exchanger 104 is located in the connecting pipeline between the outlet of the second type expansion device and the inlet of the compressor 2. Figure 2 (b) Figure 2 (d) in the figure shows schematic diagrams of the connecting pipeline of the fifth heat exchanger 105 between the outlet of the compressor 2 and the inlet of the second type expansion device 302, and the connecting pipeline between the outlet of the second type expansion device and the inlet of the compressor 2.

[0149] In addition, it should be emphasized that: according to Carnot's theorem, for the working fluid circuit of the refrigeration cycle and the power cycle, there must be at least two heat exchangers, one of which exchanges heat with an external high-temperature heat source, and the other exchanges heat with an external low-temperature heat source, and one of the heat exchangers absorbs heat from the outside, and the other absorbs heat from the outside. Therefore, in this embodiment, the first heat exchanger 101 and the second heat exchanger 102 respectively represent the heat exchangers in the first working fluid circuit that exchange heat with the external high-temperature heat source and the external low-temperature heat source when the heat pump operates in the first operating mode. It is further emphasized that it refers to the heat pump system operation. When operating in the first operating mode, the heat exchanger in the first working fluid circuit is under rated conditions or under conditions with maximum cooling and heating capacity, that is, maximum charging power. In one working fluid circuit, the heat exchanger that exchanges heat with an external high-temperature heat source should be regarded as the first heat exchanger 101, and the heat exchanger that exchanges heat with an external low-temperature heat source should be regarded as the second heat exchanger 102. When there are multiple heat exchangers, in this working fluid circuit, the heat exchanger that exchanges heat with an external high-temperature heat source can be regarded as part or all of the first heat exchanger 101, and the heat exchanger that exchanges heat with an external low-temperature heat source can be regarded as part or all of the second heat exchanger 102.

[0150] Embodiment 2:

[0151] When the heat pump system is facing cooling or heating demand, that is, when the heat pump system is operating in the first operating mode, and when the operating temperature difference of the operating medium is less than 60°C, Figure 1 As shown, the working medium passes through the second heat exchanger 102, the compressor 2, the first heat exchanger 101 and the expansion device 3 in sequence, and the working medium releases heat in the first heat exchanger 101 and absorbs heat in the second heat exchanger 102. Preferably, the first type expansion device 301 stops running, and the working medium expands and flows through the second type expansion device 302. In order to avoid losses, the clutch 13 disconnects the connection between the expander and the motor 12, and a valve is provided on the connecting pipeline of the first type expansion device 301 and the first heat exchanger 101 or the second heat exchanger 102 to disconnect the communication of the first type expansion device 301 between the first heat exchanger 101 and the second heat exchanger 102. It should be pointed out that the first type expansion device 301 is a first type expansion device, and the second type expansion device 302 is a second type expansion device.

[0152] When the heat pump system is aimed at power storage needs, the positive displacement compressor and expander can have the dual functions of working fluid compression and working fluid expansion. Figure 1As shown, the charging process: the working fluid passes through the second heat exchanger 102, the compressor 2, the first heat exchanger 101 and the first expansion device 301 in sequence, the working fluid releases heat in the first heat exchanger 101, absorbs heat in the second heat exchanger 102, and stores heat and cold in the first heat storage device 801 and the second heat storage device 802 respectively, consumes electricity in the process of producing cold and heat, and realizes charging, and the temperature difference between the average temperature of the working fluid in the first heat exchanger 101 and the average temperature in the second heat exchanger 102 is >100°C. Discharge process: For a compressor and a first-class expansion device that share the inlet and outlet, or a compressor and a first-class expansion device that use a four-way valve or other valves to achieve switching of the inlet and outlet and the heat exchanger interface, the working fluid passes through the second heat exchanger 102, the first-class expansion device 301, the first heat exchanger 101, and the compressor 2 in sequence. The working fluid absorbs the cold stored in the second heat storage device 802 in the second heat exchanger 102, is compressed in the first-class expansion device 301, and then absorbs the heat stored in the first heat storage device 801 in the first heat exchanger 101. For a compressor and a first-class expansion device whose inlet and outlet cannot be shared and which do not use a four-way valve or other valves to switch the inlet and outlet and the heat exchanger interface, the working fluid passes through the first heat exchanger 101, the first-class expansion device 301, the second heat exchanger 102, and the compressor 2 in sequence. The working fluid absorbs the cold stored in the second heat storage device 802 in the first heat exchanger 101, is compressed in the first-class expansion device 301, and then absorbs the heat stored in the first heat storage device 801 in the second heat exchanger 102. Therefore, during the discharge process, the first-class expansion device 301 plays a working fluid compression function, and the compressor 2 plays a working fluid expansion function, and the heat pump system outputs electricity by absorbing the heat and cold stored in the first heat storage device 801 and the second heat storage device 802.

[0153] When the heat pump system is aimed at power storage needs, for a single turbine machine, the efficiency is low when used for both compression and expansion. Therefore, when the compressor and expander of the heat pump system are both turbine machines, the heat pump system needs to be equipped with two compressors and two expanders, or when the heat pump system is configured with multiple positive displacement devices, such as Fig. 9As shown, the charging process: the working fluid passes through the second heat exchanger 102, the first compressor 201, the first heat exchanger 101 and the first first-type expansion device 3010 in sequence, the working fluid releases heat in the first heat exchanger 101, absorbs heat in the second heat exchanger 102, and stores heat and cold in the first heat storage device 801 and the second heat storage device 802 respectively, consumes electricity in the process of producing cold and heat, and realizes charging. The temperature difference between the average temperature of the working fluid in the first heat exchanger 101 and the average temperature in the second heat exchanger 102 is greater than 100°C; the discharging process: the working fluid The working medium passes through the second heat exchanger 102, the second compressor 202, the first heat exchanger 101, and the second first-class expansion device 3011 in sequence. The working medium absorbs the cold stored in the second heat storage device 802 in the second heat exchanger 102, is compressed in the second compressor 202, and then absorbs the heat stored in the first heat storage device 801 in the first heat exchanger 101, and expands in the second first-class expansion device 3011. The heat pump system outputs electricity by absorbing the heat and cold stored in the first heat storage device 801 and the second heat storage device 802.

[0154] In the operation facing the cooling or heating demand, the total mass of the working fluid in the heat pump system is adjusted by the mass regulating device 4, so that the mass flow rate of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 accounts for more than 10% of the total mass flow rate of the working fluid, and at the same time, the mass flow rate of the working fluid in the heat pump system passing through the second type of expansion device accounts for more than 90% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid in the heat pump system passing through the first type of expansion device accounts for less than 10% of the total mass flow rate of the working fluid.

[0155] In the operation oriented to the demand of electricity storage, the total mass of the working fluid in the heat pump system is adjusted by the mass regulating device 4 to achieve that the proportion of the mass flow rate of the liquid working fluid in the first heat exchanger 101 and / or the second heat exchanger 102 to the total mass flow rate of the working fluid is less than 10%, and at the same time, the mass flow rate of the working fluid in the heat pump system passing through the second type of expansion device is controlled to account for less than 10% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid in the heat pump system passing through the first type of expansion device is controlled to account for more than 90% of the total mass flow rate of the working fluid.

[0156] Embodiment three:

[0157] This embodiment provides a multi-purpose heat pump system for cooling, heating and electricity, including a first heat exchanger 101, a compressor 2, a second heat exchanger 102, an expansion device connected in sequence, and a motor 12, which is connected to the compressor 2. The number of expansion devices 3 is ≥2, and the types of expansion devices include first-type expansion devices and second-type expansion devices, wherein: the first-type expansion device is an expander that recovers the expansion work of the working medium expansion process and outputs mechanical work, and the number of the first-type expansion devices is ≥1; the second-type expansion device is an expansion device other than an expander, and the number of the second-type expansion devices is ≥1. The multi-purpose heat pump system for heating, cooling and electricity has at least two working fluid circuits. In the first working fluid circuit, the inlet of the compressor 2 is connected to the outlet end of the second heat exchanger 102, and the outlet of the compressor 2 is connected to the inlet end of the first heat exchanger 101. The inlet of the first type of expansion device is connected to the outlet end of the first heat exchanger 101, and the outlet of the first type of expansion device is connected to the inlet end of the second heat exchanger 102. Two pipelines are formed between the compressor 2 and the first type of expansion device. The first pipeline includes a connecting pipeline between the outlet of the compressor 2 and the inlet of the first type of expansion device 301, and the second pipeline includes a connecting pipeline between the inlet of the compressor 2 and the outlet of the first type of expansion device 301; in the second working fluid circuit, one interface of the second type of expansion device 302 is connected to the first pipeline, and the other interface of the second type of expansion device 302 is connected to the second pipeline. The multi-purpose heat pump system for heating, cooling and electricity has two operating modes; the first operating mode is the refrigeration cycle, the multi-purpose heat pump system for heating, cooling and electricity consumes electricity and generates cold and heat; the second operating mode is the power cycle, the multi-purpose heat pump system for heating, cooling and electricity consumes cold and heat and generates electricity.

[0158] The multi-purpose heat pump system for heat and cold electricity contains at least one working fluid with a critical temperature higher than 300K and at least one working fluid with a critical temperature lower than 300K. For the demand for electricity storage, its electricity storage efficiency is related to the physical properties of the working fluid. The more suitable working fluids are working fluids with a critical temperature lower than 300K, such as helium, hydrogen, argon, nitrogen, oxygen and air. For the demand for cold or heat, its cooling / heating efficiency is also related to the physical properties of the working fluid. The more suitable working fluids are working fluids with a critical temperature higher than 300K, such as R290, R410A, R32, etc. Therefore, when storing electricity, if the working fluid in the heat pump system contains more working fluids with a critical temperature higher than 300K, the electricity storage efficiency will be reduced. Similarly, if the working fluid in the heat pump system contains more working fluids with a critical temperature lower than 300K, the cooling / heating efficiency will be reduced. When storing electricity, if the working fluid in the heat pump system contains more working fluids with a critical temperature higher than 300K, the influence will be greater. The main premise of the demand for electricity storage is economic efficiency. Therefore, when the multi-purpose heat pump system for heating, cooling and electricity includes a working fluid with a critical temperature higher than 300K and a working fluid with a critical temperature lower than 300K, in order to reduce the influence of the working fluid with a critical temperature higher than 300K on the electricity storage efficiency, when operating in the first operating mode and when the working temperature difference of the operating working fluid is greater than 100°C, in the first working fluid circuit, the pressure in the first heat exchanger 101 and the second heat exchanger 102 is ≥0.5MPa; when operating in the second operating mode and when the working temperature difference of the operating working fluid is greater than 100°C, in the first working fluid circuit, the pressure in the first heat exchanger 101 and the second heat exchanger 102 is ≥0.5MPa. Preferably, under the above working conditions, the pressure in the first heat exchanger 101 and the second heat exchanger 102 is ≥1MPa. The reason for selecting 0.5MPa is that: for power storage needs, when the temperature in the second heat exchanger 102 is as low as 200K or below, taking R290 as an example, its corresponding saturation pressure at 200K is about 0.02MPa. Therefore, when the pressure in the first heat exchanger 101 and the second heat exchanger 102 is ≥0.5MPa, it is equivalent to that the proportion of working fluids with a critical temperature higher than 300K accounts for less than 5% of all working fluids. Therefore, the influence of working fluids with a critical temperature higher than 300K on power storage efficiency can be almost ignored. Moreover, since the demand for cooling or heating is based on the phase change of the working fluid, and the demand for electricity storage is based on sensible heat release or heat absorption, in order to achieve the best match between the cooling / heating capacity and the electricity storage power, when operating in the first operating mode and when the working temperature difference of the operating working fluid is greater than 100°C, in the first working fluid circuit, the pressure in the first heat exchanger 101 and the second heat exchanger 102 is ≥0.5MPa; when operating in the second operating mode and when the working temperature difference of the operating working fluid is greater than 100°C, in the first working fluid circuit, the pressure in the first heat exchanger 101 and the second heat exchanger 102 is ≥0.5MPa.

[0159] Since there are working fluids with critical temperatures higher than 300K and working fluids with critical temperatures lower than 300K in a system, and the requirements for working fluids for power storage and cold / heat demand are different, in order to achieve better performance, when operating in the first operating mode and when the operating working fluid working temperature difference is less than 60°C, the proportion of the mass flow of working fluids with critical temperatures higher than 300K in the cold, heat and electricity multi-purpose heat pump system to the total working fluid mass flow is greater than 50%, and the proportion of the mass flow of working fluids with critical temperatures lower than 300K to the total working fluid mass flow is less than 50%. Preferably, the proportion of the mass flow of working fluids with critical temperatures higher than 300K to the total working fluid mass flow is ≥99%, and the proportion of the mass flow of working fluids with critical temperatures lower than 300K to the total working fluid mass flow is less than 1%; when operating in the first operating mode and when the operating working fluid working temperature difference is greater than 100°C, the mass flow of working fluids with critical temperatures higher than 300K in the cold, heat and electricity multi-purpose heat pump system to the total working fluid mass flow is greater than 50%. The proportion of flow rate to the total working fluid mass flow rate is less than 50%, and the proportion of working fluid mass flow rate with a critical temperature below 300K to the total working fluid mass flow rate is greater than 50%. Preferably, the proportion of working fluid mass flow rate with a critical temperature above 300K to the total working fluid mass flow rate is less than 1%, and the proportion of working fluid mass flow rate with a critical temperature below 300K to the total working fluid mass flow rate is ≥99%; when operating in the second operating mode and when the operating working fluid working temperature difference is greater than 100°C, the proportion of working fluid mass flow rate with a critical temperature above 300K in the cold, heat and electricity multi-purpose heat pump system to the total working fluid mass flow rate is less than 50%, and the proportion of working fluid mass flow rate with a critical temperature below 300K to the total working fluid mass flow rate is greater than 50%. Preferably, the proportion of working fluid mass flow rate with a critical temperature above 300K to the total working fluid mass flow rate is less than 1%, and the proportion of working fluid mass flow rate with a critical temperature below 300K to the total working fluid mass flow rate is ≥99%.

[0160] In order to realize the operation of the multi-purpose heat pump system for cooling, heating and electricity according to the above-mentioned working fluid flow ratio, the following methods can be used: (1) The mass adjustment device 4, when facing the cooling or heating demand, pumps the critical temperature below 300K into the working fluid storage tank and releases the critical temperature above 300K into the heat pump system; when facing the power storage demand, pumps the working fluid with a critical temperature above 300K into the working fluid storage tank and releases the working fluid with a critical temperature below 300K into the heat pump system. This scheme has been described in detail in the first embodiment and will not be repeated here; (2) The heat exchanger is not shared, and the working fluid with a critical temperature below 300K is used in the first working fluid circuit heat exchanger for power storage demand, and the working fluid with a critical temperature above 300K is used in the second working fluid circuit heat exchanger for cooling or heating demand; (3) Taking advantage of the characteristics that the working fluid with a critical temperature above 300K is liquefied and the working fluid with a critical temperature below 300K is not liquefied, the mass flow ratio of the working fluid with a critical temperature above 300K in the total mass flow in the operating working fluid is adjusted based on gas-liquid separation.

[0161] Fig.10A heat pump system solution without sharing a heat exchanger is shown, in which the first working fluid circuit is composed of a compressor 2, a first heat exchanger 101, a first type of expansion device 301, and a second heat exchanger 102, and the second working fluid circuit is composed of a compressor 2, a third heat exchanger 103, a second type of expansion device 302, and a fourth heat exchanger 104. The working fluid in the first working fluid circuit is a working fluid with a critical temperature lower than 300K, and the working fluid in the second working fluid circuit is a working fluid with a critical temperature higher than 300K. Since the two working fluid circuits do not share a heat exchanger, a switching valve 17 is further included. The first switching valve 1701 is located at the outlet of the compressor 2, and is used to control the connection and disconnection between the outlet of the compressor 2 and the first heat exchanger 101 or the third heat exchanger 103; the second switching valve 1702 is located at the inlet of the compressor 2, and is used to control the connection between the inlet of the compressor 2 and the second heat exchanger 102 or the fourth heat exchanger 104. When the heat pump system is facing cooling or heating demand, the outlet of the compressor 2 is connected to the third heat exchanger 103 and disconnected from the first heat exchanger 101 under the action of the first switching valve 1701, and the inlet of the compressor 2 is connected to the third heat exchanger 103. The port is connected to the fourth heat exchanger 104 and disconnected from the second heat exchanger 102 at the second switching valve 1702. When the heat pump system is facing the power storage demand, the outlet of compressor 2 is disconnected from the third heat exchanger 103 and connected to the first heat exchanger 101 under the action of the first switching valve 1701, and the inlet of compressor 2 is disconnected from the fourth heat exchanger 104 and connected to the second heat exchanger 102 at the second switching valve 1702. Therefore, the working fluid in the first working fluid circuit can be a working fluid with a critical temperature lower than 300K, and the working fluid in the second working fluid circuit can be a working fluid with a critical temperature higher than 300K, thereby realizing the working fluid flow ratio operation as described above. Since there is a common compressor in the two working fluid circuits and there may be a mixture of working fluids, a working fluid pump 7 is also included. The inlet of the working fluid pump 7 is connected to the inlet or outlet of the compressor 2. The working fluid pump 7 can pump the working fluid in the compressor 2 into the first heat exchanger 101 or the second heat exchanger 102, or can pump the working fluid in the compressor 2 into the third heat exchanger 103 or the fourth heat exchanger 104. For example: in the process of switching from cooling or heating demand to power storage demand, the working fluid pump 7 can be used to pump the working fluid in the compressor 2 into the third heat exchanger 103 or the fourth heat exchanger 104; in the process of switching from power storage demand to cooling or heating demand, the working fluid pump 7 can be used to pump the working fluid in the compressor 2 into the first heat exchanger 101 or the second heat exchanger 102. Similarly, in the first working fluid circuit, the following is installed: Figure 4 The valve shown can be used for the first type of expansion device to compress the working fluid in the second working fluid circuit. Fig.10The figure shows a case where the first type expansion device 301 and the compressor 2 are connected in parallel. Depending on the situation, when facing the cooling or heating demand, the third valve 903 and the fourth valve 904 are closed, and the first valve 901 and the second valve 902 are opened. The second working fluid circuit compressor can be compressed by only the first type expansion device 301, only the compressor 2, or the first type expansion device 301 and the compressor 2. Other series connection forms can be as follows Figure 4 The valves and pipelines shown will not be described in detail.

[0162] Fig.11 A schematic diagram of a gas-liquid separation regulation of the proportion of the mass flow rate of the working fluid with a critical temperature higher than 300K in the total mass flow rate is shown. The heat pump system includes at least one gas separator 15, the gas separator 15 has a cavity inside, and has at least one interface connected to the closed cavity. When the working fluid of the heat pump system is mainly the working fluid with a critical temperature higher than 300K, the internal cavity of the gas separator 15 is used to store part or all of the working fluid with a critical temperature lower than 300K; when the working fluid of the heat pump system is mainly the working fluid with a critical temperature lower than 300K, the internal cavity of the gas separator 15 is used to store part or all of the working fluid with a critical temperature higher than 300K. Further, the gas separator 15 can realize any one or all of the following functions in the heat pump system: when operating in the first operating mode and the operating temperature difference of the operating working fluid is less than 60°C, the gas separator 15 is used to reduce the proportion of the working fluid with a critical temperature lower than 300K in the total working fluid mass flow; and or, when operating in the first operating mode and the operating temperature difference of the operating working fluid is greater than 100°C, the gas separator 15 is used to reduce the proportion of the working fluid with a critical temperature higher than 300K in the total working fluid mass flow; and or, when operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100°C, the gas separator 15 is used to reduce the proportion of the working fluid with a critical temperature higher than 300K in the total working fluid mass flow. In order to realize the above functions, the gas separator 15 can be any of the following connection conditions:

[0163] (1) The first gas separator 151 is connected to a connecting pipeline between an interface of the second type of expansion device and an outlet of the compressor 2. Specifically, the first gas separator 151 is located on a connecting pipeline between an interface of the second type of expansion device in the second working fluid circuit and the outlet of the compressor 2 and is located on a connecting pipeline between an outlet of a heat exchanger closest to the second type of expansion device in the second working fluid circuit and the second type of expansion device. When the heat pump system is operated to meet cooling or heating requirements, the working fluid is expanded by the second type expansion device 302. At this time, the most suitable working fluid for the heat pump system is the working fluid with a critical temperature higher than 300K. For working fluids with a critical temperature higher than 300K such as R290 and R32, the working fluid is compressed by the compressor 2 and then condensed into a liquid after heat release by the heat exchanger. At this time, the working fluid with a critical temperature lower than 300K is still in a gaseous state. Therefore, the working fluid with a critical temperature higher than 300K and the working fluid with a critical temperature lower than 300K are separated into gas and liquid in the first gas separator 151. The liquid is at the bottom of the first gas separator 151, and the outlet can be set inside the liquid to achieve storage of part or all of the working fluid with a critical temperature lower than 300K inside the first gas separator 151. Therefore, the first gas separator 151 is set at the working fluid inlet of the second type expansion device in the second working fluid circuit to adjust the flow ratio of different working fluids, such as Fig.11 As shown in (a) of FIG. 1 , the first gas separator 151 is located on the pipeline between an interface of the second type expansion device in the second working fluid circuit and the outlet of the third heat exchanger 103. Figure 1 , Figure 2 (e) Figure 2 (g) Figure 2 (d) Figure 2 In the heat pump system shown in (h), the first gas separator 151 is located on the connecting pipeline between the outlet of the compressor 2 and the second type expansion device 302, and further, on the pipeline between the heat exchanger near the inlet end of the second type expansion device 302 and the inlet of the second type expansion device 302;

[0164] (2) and or, the second gas separator 152 is connected to the first pipeline, or, the second gas separator 152 is connected to the second pipeline, or, the second gas separator 152 is connected to the connecting pipeline between the compressor 2 outlet and the second type of expansion device, or, the second gas separator 152 is connected to the connecting pipeline between the compressor 2 inlet and the second type of expansion device. When the heat pump system operates to meet the cooling or heating requirements, the working fluid is expanded through the first type of expansion device 301. At this time, the most suitable working fluid for the heat pump system is the working fluid with a critical temperature lower than 300K. Therefore, in order to reduce the impact of the working fluid with a critical temperature higher than 300K on the power storage efficiency, it is necessary to reduce the proportion of the working fluid with a critical temperature higher than 300K in the total working fluid flow. Fig.11 (a) and (b) in FIG. 1 show the connection between the second gas separator 152 and the second pipeline. Fig.11In (a), the second gas separator 152 is connected to the connecting pipeline between the outlet of the first type expansion device and the inlet of the second heat exchanger 102, Fig.11 In (b), the connecting pipeline between the inlet of the second gas separator 152 and the compressor 2 is connected to the outlet of the second heat exchanger 102, and the temperature of the control medium after expansion by the first expansion device 301 is relatively low. The critical temperature is higher than 300K and the medium becomes a gas-liquid two-phase state, wherein the liquid flows into the second gas separator 152 due to its larger density, and the gaseous state of the medium with a critical temperature higher than 300K and the medium with a critical temperature lower than 300K are mixed and enter the compressor 2. In order to reduce the damage of the gas-liquid two-phase to the first expansion device 301, a second expansion device can be connected in parallel at both ends of the first expansion device 301. At the initial stage of the heat pump system for power storage applications, the first expansion device 301 is stopped for expansion, and the second expansion device connected in parallel with both ends of the first expansion device 301 is enabled for working medium expansion. When the critical temperature inside the heat pump system is higher than 300K and most of the working medium is stored in the second gas separator 152 after liquefaction, the second expansion device is stopped and the first expansion device 301 is enabled. Fig.11 (c) shows the connection pipeline between the second gas separator 152 and the compressor 2 inlet and the second type expansion device, and the connection pipeline between the second gas separator 151 and the second type expansion device 302 and the fourth heat exchanger 104. Fig.11 (d) in FIG. 1 shows the connection between the second gas separator 152 and the outlet of the compressor 2 and the second type of expansion device. At the same time, Fig.11 (d) in FIG. 1 also shows that the second gas separator 152 is connected to the first pipeline, and the second gas separator 151 is located on the outlet pipeline of the compressor 2. In this case, the working fluid with a critical temperature higher than 300K entering the second gas separator 152 is in the gas phase. The second gas separator 152 requires an external cold source to cool the working fluid in the second gas separator, and condense the working fluid with a critical temperature higher than 300K in the second gas separator 152. The second gas separator 151 can also be located on the pipeline between the first heat exchanger 101 and the first type of expansion device 301. In this case, an external cold source is also required to condense the working fluid with a critical temperature higher than 300K in the second gas separator 152. It should be pointed out that the heat pump system can have only the first gas separator 151. When facing electricity storage, the working fluid with a critical temperature higher than 300K can be condensed in the first gas separator 151 through an external cold source, thereby reducing the impact of the working fluid with a critical temperature higher than 300K on the electricity storage efficiency.

[0165] In order to reduce the impact of working fluids with a critical temperature higher than 300K on power storage requirements, when operating in the first operating mode and the operating working fluid operating temperature difference is >100°C, the liquid temperature in the first gas separator 151 and / or the second gas separator 152 is controlled to be ≤273K, so as to achieve the storage of part of the working fluid with a critical temperature higher than 300K in liquid form in the first gas separator 151 and / or the second gas separator 152; when operating in the second operating mode and the operating working fluid operating temperature difference is >100°C, the liquid temperature in the first gas separator 151 and / or the second gas separator 152 is controlled to be ≤273K, so as to achieve the storage of part of the working fluid with a critical temperature higher than 300K in liquid form in the second gas separator 152. The reason for selecting 273K is that the saturation pressure of some working fluids with a critical temperature higher than 300K is very low at 273K, such as R245fa, which has a saturation pressure of about 0.05MPa at 273K. When the minimum pressure in the first heat exchanger 101 and the second heat exchanger 102 is 0.5MPa, the working fluid with a critical temperature higher than 300K accounts for about 10% of the total working fluid flow when facing the power storage demand, so the impact is relatively small. Since the lower the temperature, the lower the saturation pressure of the working fluid with a critical temperature higher than 300K, the smaller its proportion in the total working fluid flow, and the smaller the impact on the power storage demand when mixed with the working fluid with a critical temperature lower than 300K, therefore, preferably, the liquid temperature in the first gas separator 151 and / or the second gas separator 152 is controlled to be ≤220K.

[0166] The gas separator 15 may be in the form of a storage tank or a curved pipe. Fig.11 As shown in (c) in FIG. 1 , the second gas separator 152 is a bent pipe.

[0167] In addition, the gas separation method based on gas-liquid separation can also be implemented by using the third heat exchanger 103 and / or the fourth heat exchanger 104, for example Figure 2As shown in (f) in the figure, when facing the demand for power storage, since the third heat exchanger 103 and the fourth heat exchanger 104 are not used for heat exchange at this time, they can be used to store the working fluid with a critical temperature higher than 300K. For example, an external cold source is used to condense the working fluid with a critical temperature higher than 300K in the third heat exchanger. Alternatively, when the heat pump system faces power storage, the working fluid is first expanded by using the second type of expansion device, and the gas-liquid two-phase generated after the working fluid is expanded is used to keep the liquid in the fourth heat exchanger 104. In addition, an external cold source can also be used to store most of the working fluid with a critical temperature higher than 300K in the fourth heat exchanger 104. Moreover, during the charging and discharging process, the liquid temperature in the third heat exchanger 103 or the fourth heat exchanger 104 is controlled to be ≤273K. Therefore, most of the working fluid with a critical temperature higher than 300K is stored in the third heat exchanger 103 or the fourth heat exchanger 104 in liquid form, thereby reducing its proportion in the total working fluid flow. When facing cold or hot, since the first heat exchanger 101 or the second heat exchanger 102 is not used for heat exchange, it can be used to store working fluids with a critical temperature lower than 300K, for example Figure 2 As shown in (f) in the figure, since the working fluid with a critical temperature lower than 300K is in a gaseous state, when the height of the third heat exchanger 103 is smaller than that of the first heat exchanger 101, part or all of the working fluid with a critical temperature lower than 300K is concentrated in the first heat exchanger 101 due to its lighter density, thereby reducing the proportion of the working fluid with a critical temperature lower than 300K in the total working fluid flow when facing cold or hot.

[0168] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention by using the technical content disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention should fall within the scope of protection of the technical solution of the present invention.

Claims

1. A multi-purpose heat pump system for cooling, heating and electricity, comprising a first heat exchanger (101), a compressor (2), a second heat exchanger (102), and an expansion device (3) connected in sequence, and also comprising a motor (12), the motor (12) being connected to the compressor (2), characterized in that: The expansion device (3) comprises a first type of expansion device and a second type of expansion device; The first type of expansion device is an expander that recovers the expansion work of the working fluid expansion process and outputs mechanical work, and the number of the first type of expansion devices X ≥ 1; The second type of expansion device is an expansion device other than an expander, and the number of the second type of expansion devices Y ≥ 1; The multi-purpose heat pump system for heating, cooling and power generation has at least two working fluid circuits, the first working fluid circuit being composed of a first-type expansion device and a compressor (2), and the second working fluid circuit being composed of a second-type expansion device and a compressor (2) and / or a first-type expansion device, wherein: in the first working fluid circuit, the inlet of the compressor (2) is connected to the outlet end of the second heat exchanger (102), and the outlet of the compressor (2) is connected to the inlet end of the first heat exchanger (101), the inlet of the first-type expansion device is connected to the outlet end of the first heat exchanger (101), and the outlet of the first-type expansion device is connected to the inlet end of the second heat exchanger (102), and two pipelines are formed between the compressor (2) and the first-type expansion device, the first pipeline comprising a connecting pipeline between the outlet of the compressor (2) and the inlet of the first-type expansion device, and the second pipeline comprising a connecting pipeline between the inlet of the compressor (2) and the outlet of the first-type expansion device; in the second working fluid circuit, one interface of the second-type expansion device is connected to the first pipeline, and the other interface of the second-type expansion device is connected to the second pipeline; The system further comprises a mass regulating device (4), the mass regulating device (4) comprising a working fluid storage tank (5) and a control valve (6), the control valve (6) having the function of controlling the connection and disconnection between the working fluid storage tank (5) and the working fluid in the multipurpose heat pump system, pumping the working fluid in the multipurpose heat pump system into the working fluid storage tank (5) for storage or releasing the working fluid stored in the working fluid storage tank (5) into the working fluid in the multipurpose heat pump system, and being used to regulate the total mass of the working fluid in the multipurpose heat pump system; The multi-purpose heat pump system for cooling, heating and electricity contains at least one working fluid with a critical temperature higher than 300K; The multi-purpose heat pump system for cooling, heating and electricity has two operation modes; The first operation mode is a refrigeration cycle, wherein the multi-purpose heat pump system consumes electricity and generates cold and heat; The second operation mode is a power cycle, in which the cold, heat and electricity multi-purpose heat pump system consumes cold and heat to generate electricity.

2. The multi-purpose heat pump system for cooling, heating and electricity according to claim 1, characterized in that: The multi-purpose heat pump system for cooling, heating and electricity also includes a working fluid with a critical temperature lower than 300K; When operating in the first operating mode and when the operating working fluid working temperature difference is less than 60° C., the mass regulating device (4) is used to control the mass flow of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to account for more than 50% of the total working fluid mass flow, and the mass flow of the working fluid with a critical temperature lower than 300K to account for less than 50% of the total working fluid mass flow; When operating in the first operating mode and when the operating working fluid operating temperature difference is greater than 100° C., the mass regulating device (4) is used to control the mass flow of the working fluid with a critical temperature higher than 300K in the circulating working fluid flow of the multi-purpose heat pump system to account for less than 50% of the total working fluid mass flow, and the mass flow of the working fluid with a critical temperature lower than 300K to account for more than 50% of the total working fluid mass flow; When operating in the second operating mode and when the operating working fluid operating temperature difference is greater than 100° C., the mass regulating device (4) is used to control the mass flow of the circulating working fluid with a critical temperature higher than 300K in the multi-purpose heat pump system to account for less than 50% of the total mass flow of the working fluid, and the mass flow of the working fluid with a critical temperature lower than 300K to account for more than 50% of the total mass flow of the working fluid.

3. A multi-purpose heat pump system for cooling, heating and electricity, comprising a first heat exchanger (101), a compressor (2), a second heat exchanger (102), an expansion device (3) connected in sequence, and a motor (12), the motor (12) being connected to the compressor (2), characterized in that: The expansion device (3) comprises a first type of expansion device and a second type of expansion device; The first type of expansion device is an expander that recovers the expansion work of the working fluid expansion process and outputs mechanical work, and the number of the first type of expansion devices X ≥ 1; The second type of expansion device is an expansion device other than an expander, and the number of the second type of expansion devices Y ≥ 1; The multi-purpose heat pump system for heating, cooling and power generation has at least two working fluid circuits, the first working fluid circuit being composed of a first-type expansion device and a compressor (2), and the second working fluid circuit being composed of a second-type expansion device and a compressor (2) and / or a first-type expansion device, wherein: in the first working fluid circuit, the inlet of the compressor (2) is connected to the outlet end of the second heat exchanger (102), and the outlet of the compressor (2) is connected to the inlet end of the first heat exchanger (101), the inlet of the first-type expansion device is connected to the outlet end of the first heat exchanger (101), and the outlet of the first-type expansion device is connected to the inlet end of the second heat exchanger (102), and two pipelines are formed between the compressor (2) and the first-type expansion device, the first pipeline comprising a connecting pipeline between the outlet of the compressor (2) and the inlet of the first-type expansion device, and the second pipeline comprising a connecting pipeline between the inlet of the compressor (2) and the outlet of the first-type expansion device; in the second working fluid circuit, one interface of the second-type expansion device is connected to the first pipeline, and the other interface of the second-type expansion device is connected to the second pipeline; The multi-purpose heat pump system for cooling, heating and electricity contains at least one working fluid with a critical temperature higher than 300K; The multi-purpose heat pump system for cooling, heating and electricity contains at least one working fluid with a critical temperature lower than 300K; The multi-purpose heat pump system for cooling, heating and electricity has two operation modes; The first operation mode is a refrigeration cycle, wherein the multi-purpose heat pump system consumes electricity and generates cold and heat; The second operation mode is a power cycle, in which the cold, heat and electricity multi-purpose heat pump system consumes cold and heat to generate electricity.

4. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: The connection point between an interface of the second type expansion device and the first pipeline includes the outlet of the compressor (2), the inlet of the first type expansion device, and the connecting pipeline between the outlet of the compressor (2) and the inlet of the first type expansion device; The other interface of the second type of expansion device and the second pipeline connection point position include the inlet of the compressor (2), the outlet of the second type of expansion device, and the connecting pipeline between the inlet of the compressor (2) and the outlet of the first type of expansion device.

5. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: When operating in the first operating mode and when the operating temperature difference of the operating working fluid is less than 60°C, the mass flow rate of the liquid working fluid at the inlet and / or outlet of at least one expansion device is controlled to account for more than 10% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the second type of expansion device in the cold, heat and power multi-purpose heat pump system is controlled to account for more than 90% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the first type of expansion device in the cold, heat and power multi-purpose heat pump system is controlled to account for less than 10% of the total mass flow rate of the working fluid; When operating in the first operating mode and the operating temperature difference of the operating working fluid is greater than 100°C, the mass flow rate of the liquid working fluid at the inlet of at least one expansion device is controlled to account for less than 10% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the second type of expansion device in the multi-purpose heat pump system for cooling, heating and electricity is controlled to account for less than 10% of the total mass flow rate of the working fluid; the mass flow rate of the working fluid passing through the first type of expansion device in the multi-purpose heat pump system for cooling, heating and electricity is controlled to account for more than 90% of the total mass flow rate of the working fluid; When operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100°C, the proportion of the liquid working fluid mass flow at the inlet of at least one expansion device to the total working fluid mass flow is controlled to be ≤10%; the proportion of the working fluid mass flow of the operating working fluid in the cold, heat and power multi-purpose heat pump system passing through the second type of expansion device to the total working fluid mass flow is controlled to be less than 10%, and the proportion of the working fluid mass flow of the operating working fluid in the cold, heat and power multi-purpose heat pump system passing through the first type of expansion device to the total working fluid mass flow is controlled to be greater than 90%.

6. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: When operating in the first operating mode and the operating temperature difference of the operating working fluid is less than 60°C, the operating working fluid is controlled to operate according to the second working fluid circuit; When running in the first operating mode and the operating temperature difference of the operating working fluid is greater than 100°C, the operating working fluid is controlled to run according to the first working fluid loop; When operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., the operating working fluid is controlled to operate according to the first working fluid loop.

7. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: When operating in the first operating mode and the working temperature difference of the operating working fluid is less than 60°C, controlling X≥1 first-type expansion devices to stop being used for working fluid expansion; When operating in the first operating mode and the working temperature difference of the operating working fluid is greater than 100°C, Y ≥ 1 second-type expansion devices are controlled to stop being used for working fluid expansion; When operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., Y ≥ 1 second-type expansion devices are controlled to stop being used for working fluid expansion.

8. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: It also includes a first heat storage device (801) and a second heat storage device (802); The heat exchange between the heat storage device (8) and the working medium can be achieved under any of the following conditions: The heat transfer medium from the heat storage device (8) flows into the heat storage device (8) after completing heat exchange with the working medium in the first heat exchanger (101) and / or the second heat exchanger (102); And / or, the heat storage device (8) is connected in parallel with the heat exchanger, and the working fluid directly exchanges heat with the heat storage device (8).

9. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: The expansion device has an unloading operation mechanism, which is used to reduce the additional loss generated when the first type expansion device and / or the second type expansion device is not used for working medium expansion during the operation of the heat pump.

10. The multi-purpose heat pump system for cooling, heating and electricity according to claim 9, characterized in that: The unloading operation mechanism includes a clutch and a valve; When the unloading operation mechanism is a valve, the valve is arranged on the inlet or outlet pipeline of the expansion device.

11. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: When the first-type expansion device can be used for working fluid compression, the first-type expansion device is used for compressing the working fluid in the second working fluid circuit, including any of the following situations: The working fluid is all compressed in the first type of expansion device, and the working fluid is expanded through the second type of expansion device; and / or, a portion of the working fluid is compressed in a first type expansion device, another portion is compressed in a compressor (2), and the working fluid is expanded through a second type expansion device; and / or, the first type expansion device is connected in series with the compressor (2), the working fluid flows into the first type expansion device for pre-compression and flows into the compressor (2) for secondary compression, and the working fluid expands through the second type expansion device; And / or, the first type expansion device is connected in series with the compressor (2), the working medium flows into the compressor (2) for pre-compression and is compressed for a second time in the first type expansion device, and the working medium is expanded through the second type expansion device.

12. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: The compressor is composed of a compression module control valve and N≥2 compression modules.

13. The multi-purpose heat pump system for cooling, heating and electricity according to claim 12, characterized in that: Under the action of the compression module control valve, the first type of expansion device is ≥1 compression module of the compressor, that is, ≥1 compression module is used to recover the expansion work of the working fluid expansion process and output mechanical work; When operating in the first operating mode and the working temperature difference of the operating working fluid is greater than 100°C, under the action of the compression module control valve, K≥1 compression modules are used for working fluid compression, J≥1 compression modules are used for working fluid expansion, and K+J≤N; When operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., K ≥ 1 compression modules are used for working fluid compression, J ≥ 1 compression modules are used for working fluid expansion, and K + J ≤ N.

14. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: The compressor is a positive displacement compressor having ≥1 air valve, the air valve being an intake valve and / or an exhaust valve, at least one of the air valves being an actively controlled valve, and the opening and closing of the actively controlled valve is controlled by electromagnetic force, hydraulic pressure or mechanical force; And / or, the first type of expansion device is a volumetric expander having ≥1 gas valve, which is an intake valve and / or an exhaust valve, at least one of which is an actively controlled valve, and the opening and closing of the actively controlled valve is controlled by electromagnetic force, hydraulic pressure or mechanical force.

15. The multi-purpose heat pump system for cooling, heating and electricity according to claim 2, characterized in that: It also includes ≥2 mass regulating devices (4), wherein: at least one of the mass regulating devices (4) is used for mass regulating a working fluid having at least one critical temperature higher than 300K; and at least one of the mass regulating devices (4) is used for mass regulating a working fluid having a critical temperature lower than 300K.

16. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: It also includes a regenerator (10), which has a first flow channel and a second flow channel, one end of the first flow channel of the regenerator (10) is connected to the outlet end of the first heat exchanger (101), and the other end is connected to the inlet end of the first type of expansion device, and one end of the second flow channel of the regenerator (10) is connected to the outlet end of the second heat exchanger (102), and the other end is connected to the compressor (2).

17. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: When the first type of expansion device cannot be used for working fluid compression, the number of the compressors (2) is ≥ 2, wherein: when operating in the first operating mode and when the working fluid operating temperature difference is greater than 100° C., the compressor used for working fluid compression is the first compressor (201); when operating in the second operating mode and when the working fluid operating temperature difference is greater than 100° C., the compressor used for working fluid compression is the second compressor (202); When operating in the first operating mode and when the operating temperature difference of the operating working medium is less than 60° C., the second compressor (202) is used to compress the working medium in the second working medium circuit, including any of the following situations: The working medium is completely compressed in the second compressor (202), and the working medium is expanded through a second type expansion device; and / or, a portion of the working fluid is compressed in the second compressor (202), and another portion is compressed in the first compressor (201), and the working fluid is expanded through a second type expansion device; and / or, the first compressor (201) and the second compressor (202) are connected in series, the working medium flows into the second compressor (202) for pre-compression and flows into the first compressor (201) for secondary compression, and the working medium is expanded through a second type expansion device; And / or, the first compressor (201) and the second compressor (202) are connected in series, the working fluid flows into the first compressor (201) for pre-compression and flows into the second compressor (202) for secondary compression, and the working fluid is expanded through a second type of expansion device.

18. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: It also includes a third heat exchanger (103), the third heat exchanger (103) is located on the connecting pipeline between the outlet of the compressor (2) and the inlet of the second type expansion device; And / or, it further comprises a fourth heat exchanger (104), wherein the fourth heat exchanger (104) is located on the connecting pipeline between the outlet of the second type expansion device and the inlet of the compressor (2).

19. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 1 to 3, characterized in that: The second type of expansion device is an expansion device that cannot recover the expansion work of the working medium expansion process and outputs mechanical work; The second type of expansion device includes an electronic expansion valve, a thermal expansion valve, a capillary tube, an ejector or an orifice plate.

20. The multi-purpose heat pump system for cooling, heating and electricity according to claim 3, characterized in that: When operating in the first operating mode and when the operating working fluid working temperature difference is less than 60°C, the mass flow rate of the working fluid with a critical temperature higher than 300K in the multi-purpose heat pump system accounts for more than 50% of the total mass flow rate of the working fluid, and the mass flow rate of the working fluid with a critical temperature lower than 300K accounts for less than 50% of the total mass flow rate of the working fluid; When operating in the first operating mode and when the operating working fluid working temperature difference is greater than 100°C, the mass flow rate of working fluids with a critical temperature higher than 300K in the multi-purpose heat pump system accounts for less than 50% of the total mass flow rate of working fluids, and the mass flow rate of working fluids with a critical temperature lower than 300K accounts for more than 50% of the total mass flow rate of working fluids; When operating in the second operating mode and when the operating working fluid operating temperature difference is >100°C, the proportion of the working fluid mass flow rate with a critical temperature higher than 300K in the multi-purpose heat pump system to the total working fluid mass flow rate is <50%, and the proportion of the working fluid mass flow rate with a critical temperature lower than 300K to the total working fluid mass flow rate is >50%.

21. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 2 to 3, characterized in that: It also includes at least one gas separator (15), wherein the gas separator (15) has a cavity inside and at least one interface communicating with the closed cavity; The gas separator (15) can achieve the following functions: When operating in the first operating mode and the operating temperature difference of the operating working fluid is less than 60° C., the gas separator (15) is used to reduce the proportion of the working fluid with a critical temperature below 300K in the total working fluid mass flow; and / or, when operating in the first operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., the gas separator (15) is used to reduce the proportion of the working fluid with a critical temperature higher than 300K in the total working fluid mass flow; And / or, when operating in the second operating mode and the operating temperature difference of the operating working fluid is greater than 100° C., the gas separator (15) is used to reduce the proportion of working fluid with a critical temperature higher than 300K in the total working fluid mass flow.

22. The multi-purpose heat pump system for cooling, heating and electricity according to claim 21, characterized in that: The gas separator (15) can be connected in any of the following ways: The first gas separator (151) and an interface of the second type expansion device are connected to a connecting pipeline between the outlet of the compressor (2); And / or, the second gas separator (152) is connected to the first pipeline, or, the second gas separator (152) is connected to the second pipeline, or, the second gas separator (152) is connected to the connecting pipeline between the outlet of the compressor (2) and the second type of expansion device, or, the second gas separator (152) is connected to the connecting pipeline between the inlet of the compressor (2) and the second type of expansion device.

23. The multi-purpose heat pump system for cooling, heating and electricity according to claim 22, characterized in that: When operating in the first operating mode and the operating working medium working temperature difference is greater than 100°C, the temperature of the liquid in the first gas separator (151) and / or the second gas separator (152) is controlled to be ≤273K, so as to achieve that part of the working medium with a critical temperature higher than 300K is stored in the first gas separator (151) and / or the second gas separator (152) in a liquid state; when operating in the second operating mode and the operating working medium working temperature difference is greater than 100°C, the temperature of the liquid in the first gas separator (151) and / or the second gas separator (152) is controlled to be ≤273K, so as to achieve that part of the working medium with a critical temperature higher than 300K is stored in the second gas separator (152) in a liquid state; When operating in the first operating mode or the second operating mode, and the operating temperature difference of the operating working medium is greater than 100° C., the first gas separator (151) or the second gas separator (152) stores a portion of liquid working medium with a critical temperature higher than 300K, and the liquid working medium may be generated in any of the following situations: The working fluid with a critical temperature higher than 300K entering the first gas separator (151) or the second gas separator (152) is in a liquid phase or a gas-liquid two-phase phase; The working fluid with a critical temperature higher than 300K entering the first gas separator (151) or the second gas separator (152) is in the gas phase, and the gas phase working fluid is condensed into liquid in the first gas separator (151) or the second gas separator (152).

24. The multi-purpose heat pump system for cooling, heating and electricity according to claim 21, characterized in that: The gas separator (15) comprises a storage tank and a bent pipe.

25. The multi-purpose heat pump system for cooling, heating and electricity according to claim 18, characterized in that: The invention also includes a switching valve (17), wherein a first switching valve (1701) is located at the outlet of the compressor (2) and is used to control the connection and disconnection between the outlet of the compressor (2) and the first heat exchanger (101) or the third heat exchanger (103); and a second switching valve (1702) is located at the inlet of the compressor (2) and is used to control the connection between the inlet of the compressor (2) and the second heat exchanger (102) or the fourth heat exchanger (104).

26. The multi-purpose heat pump system for cooling, heating and electricity according to claim 18, characterized in that: When operating in the first operating mode or the second operating mode and the operating temperature difference of the operating working fluid is greater than 100°C, part of the working fluid with a critical temperature higher than 300K is stored in the third heat exchanger (103) or the fourth heat exchanger (104) in liquid form, and the liquid temperature in the third heat exchanger (103) or the fourth heat exchanger (104) is controlled to be ≤273K.

27. The multi-purpose heat pump system for cooling, heating and electricity according to any one of claims 2 to 3, characterized in that: When operating in the first operating mode and when the operating working fluid operating temperature difference is greater than 100° C., in the first working fluid circuit, the pressure in the first heat exchanger (101) and the second heat exchanger (102) is greater than or equal to 0.5 MPa; When operating in the second operating mode and when the operating working fluid operating temperature difference is greater than 100° C., in the first working fluid circuit, the pressure in the first heat exchanger (101) and the second heat exchanger (102) is greater than or equal to 0.5 MPa.

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