A heat dissipation system and method for an electric excavator and an electric excavator

Abstract

The embodiment of the application discloses a kind of electric excavator heat dissipation system, method and electric excavator, the system includes: refrigeration branch, first cooling branch, second cooling branch, power battery cooling loop and control module;Refrigeration branch includes compressor and condenser;First cooling branch is equipped with stop valve and cab cooling module;Second cooling branch is equipped with electronic expansion valve and heat exchanger;Power battery cooling loop is equipped with heat exchanger, power battery pack and water supply module, and power battery cooling loop and second cooling branch are exchanged by heat exchanger Heat exchange;Control module includes thermal management controller and temperature sensor, and thermal management controller obtains the cell temperature of power battery pack by temperature sensor, controls electronic expansion valve opening degree and stop valve on-off, to distribute refrigeration branch refrigerant to first cooling branch and / or second cooling branch.The technical scheme of the embodiment of the application reduces the heat dissipation cost of electric excavator heat dissipation system, and improves the heat dissipation effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of new energy and energy saving technology, and particularly relates to a heat dissipation system and method for an electric excavator and the electric excavator. BACKGROUND

[0002] With the gradual maturity of the "three-electric" technology, the manufacturing cost of electric products is continuously reduced. Compared with fuel excavators, the full life cycle cost of electric excavators is lower, and electrification has become one of the important directions of green development of electric excavators. Unlike automobiles, the working conditions of electric excavators are more severe, the use power is larger, and the heat dissipation requirements of the power battery box and the electric drive system are also higher.

[0003] The existing heat dissipation system of the electric excavator usually includes a cab air conditioning refrigeration system, an electric drive cooling system and a power battery cooling system which are independent of each other. Among them, the cab air conditioning refrigeration system and the electric drive cooling system each adopt a set of compressor, condenser and refrigerant pipeline. The electric drive cooling system and the power battery cooling system each adopt a set of cooling liquid pump and its pipeline.

[0004] However, since each cooling system has a set of independent heat dissipation equipment, the existing heat dissipation system of the electric excavator has many repeated parts, and the cost is high. Secondly, too many repeated parts in the electric excavator will lead to poor air flow and poor heat dissipation capacity. Finally, since the power battery system and the hydraulic system have occupied most of the space in the electric excavator, the available space for the heat dissipation system is limited, which leads to the need to discard the appearance size of the excavator of the same tonnage when arranging the heat dissipation system. SUMMARY

[0005] The present application provides a heat dissipation system and method for an electric excavator and the electric excavator, which reduces the cost of heat dissipation management of the electric excavator and improves the heat dissipation capacity and space utilization rate of the electric excavator.

[0006] In a first aspect, an embodiment of the present application provides a heat dissipation system for an electric excavator, which comprises: a refrigeration branch comprising a compressor and a condenser connected in sequence;

[0007] A first cooling branch, one end of which is communicated with the downstream of the condenser, and the other end of which is communicated with the upstream of the compressor, the first cooling branch being provided with a stop valve and a cab cooling module;

[0008] A second cooling branch, one end of which is communicated with the downstream of the condenser, and the other end of which is communicated with the upstream of the compressor, the second cooling branch being provided with an electronic expansion valve and a heat exchanger;

[0009] The power battery cooling circuit is provided with a heat exchanger, a power battery pack and a water supply module, and the power battery cooling circuit exchanges heat with the second cooling branch through the heat exchanger;

[0010] The control module comprises a thermal management controller and a temperature sensor, the thermal management controller acquires the temperature of the power battery pack through the temperature sensor, and controls the opening degree of the electronic expansion valve and the on-off of the stop valve according to the temperature of the power battery pack, so as to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch.

[0011] Optionally, the cab cooling module comprises:

[0012] The expansion valve and the evaporator connected with the expansion valve.

[0013] Optionally, the water supply module comprises:

[0014] The water tank is connected with the power battery pack at the water inlet, and the water outlet of the water tank is connected with the coolant pump;

[0015] The first flow valve is arranged between the coolant pump and the heat exchanger;

[0016] The first flow valve is used for adjusting the flow of the coolant output by the coolant pump.

[0017] Optionally, the electric excavator cooling system further comprises a third cooling branch;

[0018] One end of the third cooling branch is communicated with the water outlet of the coolant pump, and the other end is communicated with the water inlet of the water tank, the third cooling branch is provided with a second flow valve, an electric drive system and a radiator assembly, and the radiator assembly is located upstream of the electric drive system.

[0019] Optionally, the control module further comprises a first temperature and pressure sensor and a second temperature and pressure sensor;

[0020] The first temperature and pressure sensor is arranged on the line between the compressor and the heat exchanger;

[0021] The second temperature and pressure sensor is arranged on the line between the condenser and the electronic expansion valve;

[0022] The first temperature and pressure sensor and the second temperature and pressure sensor are electrically connected with the thermal management controller, and are used for monitoring the state of the coolant of the refrigeration branch.

[0023] Optionally, the control module further comprises a pressure switch electrically connected with the thermal management controller;

[0024] The pressure switch is used for alarming when the pressure of the coolant in the pipeline corresponding to the compressor is greater than or equal to a preset pressure threshold.

[0025] Optionally, the control module further comprises an electronic fan electrically connected with the thermal management controller, and the electronic fan is used for dissipating heat of the condenser.

[0026] In a second aspect, the embodiments of the present application further provide a method for cooling an electric excavator, which is applied to the cooling system of the electric excavator provided by any of the embodiments, and the method comprises the following steps:

[0027] obtaining a temperature of the battery cell corresponding to the power battery pack through the temperature sensor;

[0028] controlling the opening degree of the electronic expansion valve and the on-off of the stop valve according to the temperature of the battery cell, so as to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch.

[0029] Optionally, the temperature of the battery cell comprises a maximum battery cell temperature and an average battery cell temperature, and the controlling the opening degree of the electronic expansion valve and the on-off of the stop valve according to the temperature of the battery cell, so as to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch, comprises:

[0030] if the maximum battery cell temperature is greater than or equal to a maximum battery cell temperature threshold value, and the average battery cell temperature is greater than or equal to an average battery cell temperature threshold value, the refrigerant of the refrigeration branch is cut off from flowing to the cab cooling module by closing the stop valve;

[0031] if the maximum battery cell temperature is less than the maximum battery cell temperature threshold value, or the average battery cell temperature is less than the average battery cell temperature threshold value, the opening degree of the electronic expansion valve is set to a preset minimum opening degree, so that the refrigerant of the refrigeration branch is all distributed to the first cooling branch to realize cab refrigeration.

[0032] In a third aspect, the embodiments of the present application further provide an electric excavator, which comprises:

[0033] at least one cooling system of the electric excavator; and

[0034] at least one memory; the cooling system of the electric excavator comprises a thermal management controller, and the memory is in communication connection with the thermal management controller; wherein,

[0035] the memory stores a computer program executable by the at least one thermal management controller, and the computer program is executed by the at least one thermal management controller, so that the at least one thermal management controller can execute the method for cooling the electric excavator provided by any of the embodiments of the present application.

[0036] The embodiment of the present application provides a kind of electric excavator heat dissipation system, which includes: refrigeration branch, first cooling branch, second cooling branch, power battery cooling circuit and control module;Refrigeration branch includes the compressor and condenser connected in sequence;First cooling branch, one end is communicated with the downstream of condenser, the other end is communicated with the upstream of compressor, and stop valve and cab cooling module are arranged on first cooling branch;Second cooling branch, one end is communicated with the downstream of condenser, the other end is communicated with the upstream of compressor, and electronic expansion valve and heat exchanger are arranged on second cooling branch;Power battery cooling circuit, heat exchanger, power battery pack and water supply module are arranged on power battery cooling circuit, and power battery cooling circuit and second cooling branch are heat exchanged by heat exchanger;Control module includes thermal management controller and temperature sensor, and the thermal management controller obtains the cell temperature corresponding to power battery pack by temperature sensor, and controls the opening of electronic expansion valve and the on-off of stop valve according to cell temperature, to distribute refrigerant of refrigeration branch to first cooling branch and / or second cooling branch.The technical scheme of the embodiment of the present application reduces the heat dissipation cost of electric excavator heat dissipation system, and improves heat dissipation effect and space utilization.

[0037] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0039] Figure 1a It is a structure schematic view of a refrigeration branch according to the first embodiment of the present application;

[0040] Figure 1b It is a structure schematic view of a first cooling branch according to the first embodiment of the present application;

[0041] Figure 1c It is a structure schematic view of a second cooling branch according to the first embodiment of the present application;

[0042] Figure 1d It is a structure schematic view of a power battery cooling circuit according to the first embodiment of the present application;

[0043] Figure 1e It is a structure schematic view of an electric excavator heat dissipation system according to the first embodiment of the present application;

[0044] Figure 2a is a structural schematic diagram of another electric excavator heat dissipation system according to the second embodiment of the present application;

[0045] Figure 2b is a structural schematic diagram of a third cooling branch according to the second embodiment of the present application;

[0046] Figure 3a is a flow chart of an electric excavator heat dissipation method according to the third embodiment of the present application;

[0047] Figure 3b is a flow chart of a method of respectively refrigerating the power battery pack and the cab according to the third embodiment of the present application;

[0048] Figure 3c is a flow chart of a method of simultaneously cooling the power battery pack and the electric drive system according to the third embodiment of the present application;

[0049] Figure 4 is a structural schematic diagram of an electric excavator according to the fourth embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to make the personnel in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by the person of ordinary skill in the art without creative labor should belong to the protection scope of the present application.

[0051] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0052] Embodiment One

[0053] The embodiment discloses an electric excavator heat dissipation system, which comprises a refrigeration branch, a first cooling branch, a second cooling branch, a power battery cooling loop and a controller. The embodiment can be applied to the heat dissipation of the cab, the power battery pack and the electric drive system in the electric excavator.

[0054] Figure 1a is a structural schematic diagram of a refrigeration branch according to the embodiment one of the present application. As shown in the figure, Figure 1a the refrigeration branch comprises a compressor 101 and a condenser 102 connected in sequence.

[0055] Specifically, the downstream of the compressor 101 is communicated with the upstream of the condenser 102.

[0056] Figure 1b is a structural schematic diagram of a first cooling branch according to the embodiment one of the present application. As shown in the figure, Figure 1b a stop valve 103 and a cab cooling module 104 are arranged on the first cooling branch.

[0057] Specifically, the cab cooling module 104 is arranged downstream of the stop valve 103.

[0058] Figure 1c is a structural schematic diagram of a second cooling branch according to the embodiment one of the present application. As shown in the figure, Figure 1c an electronic expansion valve 105 and a heat exchanger 106 are arranged on the second cooling branch.

[0059] Specifically, the heat exchanger 106 can be arranged downstream of the electronic expansion valve 105.

[0060] Figure 1d is a structural schematic diagram of a power battery cooling loop according to the embodiment one of the present application. As shown in the figure, Figure 1d the heat exchanger 106, a power battery pack 107 and a water supply module 108 are arranged on the power battery cooling loop.

[0061] Specifically, one end of the power battery pack 107 is communicated with the downstream of the heat exchanger 106, and the other end is communicated with the upstream of the water supply module 108.

[0062] Figure 1e is a structural schematic diagram of an electric excavator heat dissipation system according to the embodiment one of the present application. As shown in the figure, Figure 1eAs shown, the refrigeration branch includes a compressor 101 and a condenser 102 connected in sequence; a first cooling branch, one end of which is communicated with the downstream of the condenser 102, and the other end of which is communicated with the upstream of the compressor 101, the first cooling branch being provided with a stop valve 103 and a cab cooling module 104; a second cooling branch, one end of which is communicated with the downstream of the condenser 102, and the other end of which is communicated with the upstream of the compressor 101, the second cooling branch being provided with an electronic expansion valve 105 and a heat exchanger 106; a power battery cooling circuit, the power battery cooling circuit being provided with the heat exchanger 106, a power battery pack 107 and a water supply module 108, the power battery cooling circuit and the second cooling branch exchanging heat through the heat exchanger 106; and a control module, the control module including a water tank communicated with the downstream of the power battery pack, a thermal management controller 109 acquiring a temperature of an electric cell corresponding to the power battery pack 107 through a temperature sensor 110, and controlling the opening degree of the electronic expansion valve 105 and the on-off of the stop valve 103 according to the temperature of the electric cell, so as to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch.

[0063] In the embodiment, the compressor 101 can be used to convert low-pressure gas into high-temperature and high-pressure gas. The condenser 102 can be used to convert the high-temperature and high-pressure gas output by the compressor 101 into low-temperature and high-pressure liquid. The stop valve 103 is used to cut off the flow of the refrigerant of the refrigeration branch to the cab cooling module 104. The cab refrigeration module 104 can be used to refrigerate the cab according to the refrigerant of the refrigeration branch. The water supply module 108 can be used to drive the flow of the cooling liquid in the power battery cooling circuit. Optionally, the power battery pack 107 can be arranged in a power battery tank to insulate and waterproof the power battery pack.

[0064] In one specific embodiment, for the first cooling branch, the stop valve 103 and the cab cooling module 104 can be arranged in sequence downstream of the condenser 102 to cut off the flow of the refrigerant of the refrigeration branch to the cab cooling module 104. For the second cooling branch, the electronic expansion valve 105 can be arranged downstream of the condenser 102 to control the flow of the refrigerant distributed to the power battery cooling circuit. Then, part of the heat of the power battery pack 107 can be transferred to the refrigerant in the power battery cooling circuit through the heat exchanger 106 to achieve power battery cooling.

[0065] For example, in the case of cooling only the power battery pack 107, the stop valve 103 can be closed, and the opening degree of the electronic expansion valve 105 can be adjusted to a preset maximum opening degree to distribute all the refrigerant of the refrigeration branch to the second cooling branch.

[0066] In the case of refrigerating only the cab, the stop valve 103 can be opened, and the opening degree of the electronic expansion valve 105 can be adjusted to a preset minimum opening degree to distribute all the refrigerant of the refrigeration branch to the first cooling branch.

[0067] In the case of simultaneously refrigerating the power battery pack 107 and the cab, the stop valve 103 can be opened, and the opening degree of the electronic expansion valve 105 is adjusted according to the preset power battery pack inlet cooling liquid temperature, so that the refrigerant of the refrigeration branch is distributed to the first cooling branch and the second cooling branch.

[0068] The advantage of such an arrangement is that, compared with the existing electric excavator heat dissipation system, the cab and the power battery pack each use a set of independent heat dissipation equipment, which causes mutual interference between the sets of heat dissipation equipment and poor heat dissipation effect. In the technical solution of the present embodiment, the cab and the power battery pack share the compressor and the condenser through the first cooling branch and the second cooling branch, respectively, which avoids blockage of the excavator air duct and improves the heat dissipation effect. Secondly, the technical solution of the present embodiment reduces the number of repeated parts and reduces the cost of heat dissipation management of the electric excavator. Finally, since the electric excavator heat dissipation system in the present embodiment can be distributed in the electric excavator, the space utilization of the electric excavator is improved.

[0069] The technical solution of the present embodiment provides an electric excavator heat dissipation system, which comprises: a refrigeration branch comprising a compressor and a condenser connected in sequence; a first cooling branch, one end of which is communicated with the downstream of the condenser, and the other end of which is communicated with the upstream of the compressor, the first cooling branch being provided with a stop valve and a cab cooling module; a second cooling branch, one end of which is communicated with the downstream of the condenser, and the other end of which is communicated with the upstream of the compressor, the second cooling branch being provided with an electronic expansion valve and a heat exchanger; a power battery cooling circuit, the power battery cooling circuit being provided with a heat exchanger, a power battery pack and a water supply module, the power battery cooling circuit and the second cooling branch being heat exchanged through the heat exchanger; a control module comprising a thermal management controller and a temperature sensor, the thermal management controller acquiring the cell temperature corresponding to the power battery pack through the temperature sensor, and controlling the opening degree of the electronic expansion valve and the on-off of the stop valve according to the cell temperature, so as to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch. The problem that each of the cab and the power battery pack uses a set of independent heat dissipation equipment, resulting in a large number of repeated parts and high cost, is solved, the cost of heat dissipation management of the electric excavator is reduced, and the heat dissipation effect and the space utilization are improved.

[0070] Embodiment Two

[0071] Figure 2a is a structural schematic diagram of another electric excavator heat dissipation system provided according to Embodiment Two of the present application, which is a further optimization and expansion based on each of the above embodiments and can be combined with each of the optional technical solutions in the above embodiments.

[0072] As Figure 2aAs shown, the electric excavator cooling system disclosed in this embodiment includes: a cooling branch, which includes a compressor 101 and a condenser 102; a first cooling branch, which includes a shut-off valve 103 and a cab cooling module 104; a second cooling branch, which includes an electronic expansion valve 105 and a heat exchanger 106; a power battery cooling circuit, which includes a power battery pack 107 and a water supply module; and a control module, which includes a thermal management controller 109 and a temperature sensor 110.

[0073] Optional, such as Figure 2a As shown, the cab cooling module 104 includes an expansion valve 201 and an evaporator 202 connected to the expansion valve 201.

[0074] In this embodiment, one end of the expansion valve 201 is connected downstream of the shut-off valve 103, and the other end is connected upstream of the evaporator 202. The expansion valve 201 is used to receive the refrigerant output from the condenser 102 and atomize the refrigerant when the shut-off valve 103 is open. In practical applications, the atomized refrigerant output from the expansion valve 201 can be vaporized by the evaporator 202 to absorb heat from the cab, achieving a cooling effect for the cab.

[0075] Optional, such as Figure 2a As shown, the water supply module includes a water tank 203, the inlet of which is connected to the power battery pack 107, and the outlet of which is connected to a coolant pump 204; a first flow valve 205 is provided between the coolant pump 204 and the heat exchanger 106.

[0076] In this embodiment, the water tank 203 can be used to store coolant. The coolant pump 204 can be used to receive and drive the coolant output from the water tank 203 to circulate within the power battery cooling circuit. The first flow valve 205 can be used to regulate the flow rate of the power battery coolant circuit.

[0077] Specifically, the coolant in the water tank 203 can be delivered to the first flow valve 205 by the coolant pump 204. Then, the opening of the first flow valve 205 can be controlled by the thermal management controller 109, thereby controlling the coolant flow rate of the heat exchanger 106. Finally, the power battery pack 107 can be cooled by the heat exchanger 106.

[0078] Figure 2b This is a schematic diagram of a third cooling branch provided according to Embodiment 2 of the present invention.

[0079] Based on the above implementation methods, optionally, such as Figure 2bAs shown, the electric excavator cooling system further comprises a third cooling branch; one end of the third cooling branch is communicated with the water outlet of the cooling liquid pump 204, and the other end is communicated with the water inlet of the water tank 203; the second flow valve 206, the electric drive system 207 and the radiator assembly 208 are arranged on the third cooling branch, and the radiator assembly 208 is located upstream of the electric drive system 207.

[0080] In this embodiment, one end of the second flow valve 206 is communicated downstream of the cooling liquid pump 204, and the other end is communicated upstream of the radiator assembly 208. The electric drive system 207 is arranged downstream of the radiator assembly 208, and the water tank 203 is arranged downstream of the electric drive system 207.

[0081] Specifically, the second flow valve 206 is used to control the corresponding cooling liquid flow of the third cooling branch, that is, the cooling liquid flow delivered to the radiator assembly 208. The radiator assembly 208 can include a water inlet chamber, a water outlet chamber and a radiator, etc. The radiator assembly 208 is used to absorb the heat of the electric drive system 207 according to the cooling liquid, so as to cool the electric drive system 207. The electric drive system 207 can include a drive motor, a transmission, a power converter and a motor controller, etc.

[0082] The advantages of such arrangement are that, compared with the prior art in which the electric drive system and the power battery pack each adopt a set of independent cooling device, the corresponding flow fields of each cooling device interfere with each other, and the air duct of the whole machine is not smooth. The technical solution of the embodiment controls the cooling liquid flow distributed to the power battery cooling circuit and the third cooling branch by adjusting the first flow valve and the second flow valve, so as to realize that the electric drive system and the power battery pack share a set of cooling water pump and pipeline, avoid the blockage of the air duct of the whole machine caused by too many repeated parts, improve the cooling effect, and reduce the cost of cooling management of the electric excavator. Secondly, the electric excavator of the embodiment adopts integrated cooling, so that the cooling flow field is more smooth, the cooling effect and the service life of the power battery and other parts are improved.

[0083] Optionally, as shown in the figure, Figure 2a As shown, the control module further comprises: a first temperature and pressure sensor 209 and a second temperature and pressure sensor 210; the first temperature and pressure sensor 209 is arranged on the line between the compressor 101 and the heat exchanger 106; the second temperature and pressure sensor 210 is arranged on the line between the condenser 102 and the electronic expansion valve 105; the first temperature and pressure sensor 209 and the second temperature and pressure sensor 210 are electrically connected with the thermal management controller 109, and the first temperature and pressure sensor 209 and the second temperature and pressure sensor 210 are used to monitor the state of the cooling liquid corresponding to the refrigeration branch.

[0084] In actual application, the thermal management controller 109 can receive the cooling liquid state (such as temperature and pressure, etc.) acquired by the first temperature pressure sensor 209 and the second temperature pressure sensor 210, and adjust the electronic expansion valve 105 according to the cooling liquid temperature to realize the power battery pack cooling. Alternatively, the thermal management controller 109 can adjust the electronic expansion valve 105 and the stop valve 103 according to the cooling liquid pressure to avoid that the cooling liquid pressure is too large to cause the compressor 101 damage and the refrigeration branch failure.

[0085] Optionally, as shown in Figure 2a The control module further comprises a pressure switch 211 electrically connected with the thermal management controller 109. The pressure switch 211 is configured to alarm when the cooling liquid pressure in the pipeline corresponding to the compressor 101 is greater than or equal to a preset pressure threshold.

[0086] Optionally, as shown in Figure 2a The control module further comprises an electronic fan 212 electrically connected with the thermal management controller 109. The electronic fan 212 is configured to dissipate heat for the condenser 102.

[0087] Specifically, the thermal management controller 109 can control the rotating speed of the electronic fan 212 according to preset calibration data to meet the heat dissipation requirements of the refrigerant, the condenser 102 and the electric drive system 207.

[0088] The advantage of such an arrangement is that the air flow of the electric excavator heat dissipation system is improved by setting the electronic fan, thereby improving the heat dissipation capacity of the electric excavator.

[0089] Optionally, as shown in Figure 2a The control module further comprises a water temperature sensor 213.

[0090] In this embodiment, the water temperature sensor 213 is electrically connected with the thermal management controller 109. The water temperature sensor 213 is arranged on the line between the cooling water pump 204 and the first flow valve 205, and is configured to monitor the cooling liquid temperature of the power battery cooling circuit.

[0091] The advantage of such an arrangement is that the power battery pack always works in the optimal cell temperature range by setting the temperature sensor and the water temperature sensor, thereby improving the power battery life.

[0092] The technical scheme of the embodiment provides a heat dissipation system of an electric excavator, which comprises a refrigeration branch, a first cooling branch, a second cooling branch, a third cooling branch, a power battery cooling loop and a control module; the first cooling branch comprises a stop valve and a cab cooling module, the cab cooling module comprises an electronic expansion valve and an evaporator connected with the electronic expansion valve; the power battery cooling loop comprises a power battery pack, a water supply module and a heat exchanger; the water supply module comprises a water tank, a water inlet of the water tank is connected with the power battery pack, and a water outlet of the water tank is connected with a coolant pump; a first flow valve is arranged between the coolant pump and the heat exchanger; the first flow valve is used for adjusting the flow of the coolant output by the coolant pump; one end of the third cooling branch is communicated with a water outlet of the coolant pump, and the other end of the third cooling branch is communicated with a water inlet of the water tank; a second flow valve, an electric drive system and a radiator assembly are arranged on the third cooling branch, and the radiator assembly is located upstream of the electric drive system; the control module comprises a thermal management controller, a temperature sensor, a first temperature and pressure sensor and a second temperature and pressure sensor, which solves the problem that a plurality of repeated parts and high cost are caused by the fact that the cab, the power battery pack and the electric drive system each adopt a set of independent heat dissipation equipment, reduces the cost of heat dissipation management of the electric excavator, and improves the heat dissipation effect and the space utilization rate. Secondly, the heat dissipation system of the electric excavator in the embodiment adopts integrated heat dissipation, improves the energy utilization rate of the heat dissipation system, and further improves the endurance of the electric excavator. Finally, the integrated heat dissipation can effectively reduce the noise of the whole machine, and improves the driving experience.

[0093] Embodiment three

[0094] Figure 3a It is a flow chart of a heat dissipation method of an electric excavator according to the embodiment three of the application, the embodiment is further optimization and expansion based on the above-mentioned embodiments, and can be combined with each optional technical scheme in the above-mentioned embodiments.

[0095] As Figure 3a shown, the heat dissipation method of the electric excavator disclosed in the embodiment is applied to the thermal management controller of any embodiment of the application, and the method comprises the following steps.

[0096] In S110, the temperature sensor is used to obtain the battery cell temperature corresponding to the power battery pack.

[0097] In the embodiment, the battery cell temperature can include the maximum battery cell temperature, the minimum battery cell temperature and the average battery cell temperature.

[0098] In S120, the opening degree of the electronic expansion valve and the on-off of the stop valve are controlled according to the battery cell temperature, so that the refrigerant of the refrigeration branch is distributed to the first cooling branch and / or the second cooling branch.

[0099] Specifically, first, the state of the electric excavator can be acquired. The state of the electric excavator can include a working state and a charging state. Then, when the electric excavator is in the working state or the charging state, the opening degree of the electronic expansion valve and the on-off of the stop valve can be controlled according to the battery cell temperature.

[0100] In one specific embodiment, when the electric excavator is in the charging state, if the battery cell temperature is greater than or equal to a preset temperature threshold, the stop valve can be closed, and the opening degree of the electronic expansion valve can be adjusted according to a first preset temperature (such as 15℃±5℃). The first preset temperature can be a preset required cooling liquid temperature at the power battery pack inlet when the electric excavator is in the charging state.

[0101] Figure 3b is a flow chart of a method for respectively cooling the power battery pack and the cab according to Embodiment Three of the present application.

[0102] As shown in Figure 3b , first, it can be determined whether the electric excavator is in the working state. If the electric excavator is not in the working state, it can be determined whether the electric excavator is in the charging state. If yes, it can be determined whether the power battery cooling condition is met according to the battery cell temperature. If the battery cell temperature meets the power battery cooling condition (i.e., the battery cell temperature is greater than or equal to a preset temperature threshold), the stop valve can be closed, and the corresponding opening degrees of the sub-expansion valve and the first flow valve can be set to a preset maximum opening degree.

[0103] If the electric excavator is in the working state, it can be determined whether to cool the power battery pack or the cab. If yes, the electronic expansion valve and the first flow valve can be adjusted.

[0104] In one optional embodiment of the present application, controlling the opening degree of the electronic expansion valve and the on-off of the stop valve according to the battery cell temperature to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch includes: if the maximum battery cell temperature is greater than or equal to a maximum battery cell temperature threshold, and the average battery cell temperature is greater than or equal to an average battery cell temperature threshold, the refrigerant of the refrigeration branch is cut off from flowing to the cab cooling module by closing the stop valve; if the maximum battery cell temperature is less than the maximum battery cell temperature threshold, or the average battery cell temperature is less than the average battery cell temperature threshold, the opening degree of the electronic expansion valve is set to a preset minimum opening degree, so that the refrigerant of the refrigeration branch is all distributed to the first cooling branch to achieve cab cooling.

[0105] In one specific embodiment, for the scenario of only cooling the power battery pack, the electric excavator is in a charging state, if the maximum battery cell temperature is greater than or equal to the battery cell temperature maximum threshold value, and the average battery cell temperature is greater than or equal to the average battery cell temperature threshold value, the shut-off valve can be closed, the opening degree corresponding to the second flow valve is reduced, and the opening degree of the first flow valve is set to a preset maximum opening degree, so as to cool the power battery pack with the maximum refrigeration capacity. Specifically, the preset maximum opening degree can be 100%.

[0106] The advantage of such setting is that, since the working temperature and heat generation power of the power battery pack are the largest and the heat generation of the electric drive system is the smallest when the excavator is in a charging state, the technical solution of the present embodiment can realize cooling the power battery pack with the maximum refrigeration capacity by closing the shut-off valve and setting the opening degree of the first flow valve to the preset maximum opening degree.

[0107] For the scenario of only refrigerating the cab, the electric excavator is in a working state, if the maximum battery cell temperature is less than the battery cell temperature maximum threshold value, or the average battery cell temperature is less than the average battery cell temperature threshold value, the instrument refrigeration instruction can be received by the thermal management controller, and the electronic expansion valve opening degree is controlled to be a preset minimum opening degree, so that the refrigerant of the refrigeration branch only flows to the cab. Specifically, the preset minimum opening degree can be 0%. At this time, the electric drive system cooling liquid flow is preferentially the power battery, the second flow valve opening degree is adjusted to the preset maximum opening degree, and the opening degree of the first flow valve is constant, so as to keep the cooling liquid corresponding to the power battery pack circulating.

[0108] The advantage of such setting is that, since the cab refrigeration is only allowed to be started when the excavator is in a working state, and is prohibited when the excavator is charging, the technical solution of the present embodiment can realize refrigerating the cab with the maximum refrigeration capacity and keeping the cooling liquid corresponding to the power battery pack circulating by setting the electronic expansion valve opening degree to the preset minimum opening degree and keeping the opening degree of the first flow valve constant.

[0109] For the scenario of simultaneously refrigerating the cab and the power battery pack, the electric excavator is in a working state, if the maximum battery cell temperature is greater than or equal to the battery cell temperature maximum threshold value, and the average battery cell temperature is greater than or equal to the average battery cell temperature threshold value, the opening degree of the electronic expansion valve can be controlled according to the preset calibration value according to the calibration table. The opening degrees of the first flow valve and the second flow valve are adjusted according to the second preset temperature (such as 18℃±5℃). The above-mentioned second preset temperature can be the cooling liquid temperature at the inlet of the power battery pack when the electric excavator is in a working state.

[0110] The advantage of such arrangement is that, since the excavator is in working state when compared to charging state, the heat generation power of the power battery pack is smaller, therefore, the technical solution of the embodiment can realize cooling the electric drive system, the power battery pack and the cab at the same time by opening the cut-off valve and adjusting the opening degree of the first flow valve and the second flow valve according to the second preset temperature.

[0111] Figure 3c is a flow chart of a method for cooling the power battery pack and the electric drive system at the same time according to the third embodiment of the present application.

[0112] As shown in Figure 3c , it is judged whether the electric excavator is in charging state. If yes, the second flow valve can be closed and the first flow valve can be adjusted according to the first preset temperature. Then, the cooling liquid can be transported to the heat exchanger through the first flow valve by the cooling water pump. After that, the power battery pack can be cooled by the cooling liquid through the heat exchanger. Finally, the used cooling liquid is stored in the water tank.

[0113] If no, it is judged whether the power battery pack is cooled according to the cell temperature. If the power battery pack is cooled, the first flow valve and the second flow valve are adjusted according to the first preset temperature. If the power battery pack is not cooled, the first flow valve is closed and the second flow valve is adjusted. Then, the electric drive system can be cooled by the cooling liquid output through the second flow valve by the radiator assembly. Finally, the used cooling liquid is stored in the water tank.

[0114] The technical solution of the embodiment solves the problem of more repeated parts and higher cost caused by the fact that the cab, the power battery pack and the electric drive system each adopt a set of independent cooling equipment by the technical means that the temperature sensor acquires the cell temperature corresponding to the power battery pack and the opening degree of the electronic expansion valve and the on-off of the cut-off valve are controlled according to the cell temperature to distribute the refrigerant of the refrigeration branch to the first cooling branch and / or the second cooling branch, thereby reducing the cost of heat dissipation management of the electric excavator and improving the heat dissipation effect and space utilization.

[0115] Embodiment Four

[0116] Figure 4 shows a structural schematic diagram of an electric excavator 10 which can be used to implement the embodiments of the present application. As Figure 4As shown, the electric excavator 10 includes at least one thermal management controller 11, and a memory, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., communicatively connected to the at least one thermal management controller 11, where the memory stores a computer program executable by the at least one thermal management controller. The thermal management controller 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or loaded from the storage unit 18 into the random access memory (RAM) 13. Various programs and data required for the operation of the electric excavator 10 can also be stored in the RAM 13. The thermal management controller 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0117] Various components in the electric excavator 10 are connected to the I / O interface 15, including an input unit 16, such as a keyboard, a mouse, etc., an output unit 17, such as various types of displays, speakers, etc., a storage unit 18, such as a magnetic disk, an optical disk, etc., and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electric excavator 10 to exchange information / data with other devices through a computer network, such as the Internet, and / or various telecommunication networks.

[0118] The thermal management controller 11 can be various general and / or special purpose processing components with processing and computing capabilities. Some examples of the thermal management controller 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various thermal management controllers running machine learning model algorithms, a digital signal thermal management controller (DSP), and any appropriate thermal management controller, controller, microcontroller, etc. The thermal management controller 11 performs various methods and processes described above, such as the electric excavator thermal management method.

[0119] In some embodiments, the electric excavator thermal management method can be implemented as a computer program tangibly embodied in a computer readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on the electric excavator 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the thermal management controller 11, one or more steps of the electric excavator thermal management method described above can be performed. Alternatively, in other embodiments, the thermal management controller 11 can be configured to perform the electric excavator thermal management method by any other appropriate means, such as by means of firmware.

[0120] The various embodiments of the systems and techniques described above can be implemented in digital electronic circuitry, integrated circuitry, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on a chip (SOC), a load programmable logic device (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include implementation in one or more computer programs that are executable and / or interpretable on a programmable thermal management controller, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0121] Computer programs used to implement the processes of the application can be written in any combination of one or more programming languages. These computer programs can be provided to a thermal management controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer program, when executed, can cause the functions / operations specified in the flow charts and / or block diagrams to be implemented. The computer program can be executed entirely on a machine, partially on a machine, partially on a machine as a standalone software package and partially on a remote machine or entirely on a remote machine or server.

[0122] In the context of the present application, a computer-readable storage medium can be a tangible medium that can contain or store computer programs for use by or in connection with an instruction execution system, apparatus, or device. Computer-readable storage media can include, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium will include one or more lines of electrical connections, portable computer disks, hard disk drives, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or Flash memory), optical fibers, portable compact disc read-only memories (CD-ROMs), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0123] To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic excavator having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic excavator. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0124] The systems and techniques described here can be implemented in a computing system that includes a back end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front end component (e.g., a user computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0125] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. A server can be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system, to solve the defects of large management difficulty and weak business scalability in traditional physical host and VPS service.

[0126] It should be understood that the various forms of flow shown above can be re-ordered, added to, or deleted from without departing from the scope of the present disclosure. For example, the steps recited in the present disclosure can be executed in parallel, executed in sequence, or executed in a different order, as long as the desired results of the present disclosure are achieved, and the present disclosure is not limited herein.

[0127] The specific embodiments described above are not intended to be limiting, and persons skilled in the art will appreciate that various modifications, combinations, sub-combinations and alternatives can be made to the specific embodiments without departing from the spirit and principles of the disclosure. Accordingly, the disclosure is not limited to the specific embodiments described above, but only by the scope of the appended claims.

Claims

1. A cooling system for an electric excavator, characterized in that, The electric excavator cooling system includes: A refrigeration branch, which includes a compressor and a condenser connected in sequence; The first cooling branch has one end connected to the downstream of the condenser and the other end connected to the upstream of the compressor. A shut-off valve and a cab cooling module are provided on the first cooling branch. The second cooling branch has one end connected to the downstream of the condenser and the other end connected to the upstream of the compressor. An electronic expansion valve and a heat exchanger are provided on the second cooling branch. A power battery cooling circuit is provided, which includes a heat exchanger, a power battery pack and a water supply module. The power battery cooling circuit and the second cooling branch exchange heat through the heat exchanger. The water supply module includes: a water tank, the inlet of which is connected to the power battery pack, and the outlet of which is connected to a coolant pump; a first flow valve is provided between the coolant pump and the heat exchanger; the first flow valve is used to regulate the flow rate of the coolant output by the coolant pump. The third cooling branch has one end connected to the outlet of the coolant pump and the other end connected to the inlet of the water tank. The third cooling branch is equipped with a second flow valve, an electric drive system and a radiator assembly. The radiator assembly is located upstream of the electric drive system. The control module includes a thermal management controller and a temperature sensor. The thermal management controller obtains the cell temperature corresponding to the power battery pack through the temperature sensor, and controls the opening degree of the electronic expansion valve and the on / off state of the shut-off valve according to the cell temperature, so as to distribute the refrigerant of the cooling branch to at least one cooling branch.

2. The electric excavator cooling system according to claim 1, characterized in that, The cab cooling module includes: An expansion valve, and an evaporator connected to the expansion valve.

3. The electric excavator cooling system according to claim 1, characterized in that, The control module further includes: a first temperature and pressure sensor and a second temperature and pressure sensor; The first temperature and pressure sensor is installed on the line between the compressor and the heat exchanger; The second temperature and pressure sensor is installed on the line between the condenser and the electronic expansion valve; The first temperature and pressure sensor and the second temperature and pressure sensor are electrically connected to the thermal management controller. The first temperature and pressure sensor and the second temperature and pressure sensor are used to monitor the state of the coolant in the corresponding cooling branch.

4. The electric excavator cooling system according to claim 1, characterized in that, The control module further includes a pressure switch electrically connected to the thermal management controller; The pressure switch is used to issue an alarm when the coolant pressure in the corresponding pipeline of the compressor is greater than or equal to a preset pressure threshold.

5. The electric excavator cooling system according to claim 1, characterized in that, The control module further includes an electronic fan electrically connected to the thermal management controller, the electronic fan being used to dissipate heat from the condenser.

6. A method for heat dissipation in an electric excavator, characterized in that, The electric excavator heat dissipation method is applied to the electric excavator heat dissipation system as described in any one of claims 1-5, and the electric excavator heat dissipation method includes: The temperature of the corresponding cells in the power battery pack is obtained through a temperature sensor. The opening degree of the electronic expansion valve and the on / off state of the shut-off valve are controlled according to the cell temperature to distribute the refrigerant of the refrigeration branch to at least one cooling branch.

7. The heat dissipation method for an electric excavator according to claim 6, characterized in that, The cell temperature includes a maximum cell temperature and an average cell temperature. The step of controlling the opening of the electronic expansion valve and the on / off state of the shut-off valve based on the cell temperature to distribute the refrigerant in the cooling branch to the first cooling branch and / or the second cooling branch includes: If the maximum cell temperature is greater than or equal to the maximum cell temperature threshold, and the average cell temperature is greater than or equal to the average cell temperature threshold, then by closing the shut-off valve, the refrigerant in the cooling branch is stopped from flowing to the cab cooling module. If the maximum cell temperature is less than the maximum cell temperature threshold, or the average cell temperature is less than the average cell temperature threshold, the opening of the electronic expansion valve is set to a preset minimum opening, so that all the refrigerant in the cooling branch is distributed to the first cooling branch to achieve cab cooling.

8. An electric excavator, characterized in that, The electric excavator includes: The electric excavator cooling system according to any one of claims 1-5; and At least one memory is included, and the electric excavator cooling system includes a thermal management controller, wherein the memory is communicatively connected to the thermal management controller; wherein... The memory stores a computer program that can be executed by the at least one thermal management controller to enable the at least one thermal management controller to perform the electric excavator cooling method according to any one of claims 6-7.

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