Control method and device of heat pump steam system, controller

Abstract

The application relates to a heat pump steam system control method and device, and a controller. The heat pump steam system control method comprises the following steps: obtaining a steam quality increasing adjustment instruction; judging whether the heat pump steam system is in a flash mode or a hot water mode; if the heat pump steam system is in the flash mode, opening a steam outlet, closing a hot water outlet, and closing an electric heating element to increase the output power of the heat pump system; if the current steam quality does not meet a set steam quality and a first preset condition is met, the system is controlled to enter the hot water mode, the steam outlet is closed, the hot water outlet is opened, and the electric heating element is started. The heat pump steam system control method has the advantages of high efficiency in generating required steam and low energy consumption of the system.

Description

Technical Field

[0001] This invention relates to the field of heat pump steam generation technology, and in particular to control methods, devices, and controllers for heat pump steam systems. Background Technology

[0002] A heat pump steam generator uses a heat pump system to heat and pressurize water through heat exchange, then uses the pressure difference to flash steam into the water in a flash tank. To further increase the flash temperature of the water and produce higher-quality steam from the high-temperature, high-pressure hot water, the conventional approach is to raise the heat pump condensing temperature, thereby increasing the flash steam temperature. Therefore, traditional heat pumps use special high-temperature refrigerants, such as R1336mzz(Z), or employ a cascade heat pump system to further increase the condensing temperature.

[0003] In traditional steam generation systems, it is often necessary to adjust the quality of the steam, meaning different temperatures or pressures are required. When improving steam quality, the temperature or pressure of the output steam needs to be increased, which the system does by raising the condensing temperature of the heat pump system. Due to the lack of adaptive adjustment based on steam quality, when high steam quality requirements are needed, the only solution is to increase the power of the heat pump system. Therefore, to adjust steam quality, heat pump systems often require complex and costly high-power systems. However, continuously operating the heat pump system at high power consumes a large amount of energy and results in low steam generation efficiency. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide a control method and device for a heat pump steam system, and a controller. By controlling a heat pump steam system equipped with an electric heating element, the applicability is adjusted according to the steam quality. The system determines a first preset condition and switches between electric heating and flash steam generation to meet the steam quality requirements. It has the advantages of high efficiency in generating the required steam and low system energy consumption.

[0005] This invention is achieved through the following scheme:

[0006] In a first aspect, the present invention provides a control method for a heat pump steam system, the heat pump steam system comprising a heat pump system and a hot water circulation flash evaporation system, wherein the refrigerant pipeline of the heat pump system and the water circulation pipeline of the hot water circulation flash evaporation system are coupled through a first condenser for heat exchange.

[0007] The hot water circulation flash evaporation system includes a booster pump, a three-way shut-off valve, and a flash tank connected sequentially through the water circulation pipeline; the booster pump has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve is installed on the water supply pipeline; the three-way shut-off valve includes a hot water inlet, a steam outlet, and a hot water outlet, the hot water inlet being connected to the outlet of the first condenser through the water circulation pipeline, the steam outlet being connected to the saturated steam zone of the flash tank, and the hot water outlet being connected to the saturated water zone of the flash tank; a steam outlet valve is provided at the top of the flash tank; an electric heating element is provided inside the flash tank; the control method includes the following steps:

[0008] Obtain steam quality improvement adjustment instructions;

[0009] Determine whether the heat pump steam system is in flash mode or hot water mode;

[0010] In flash evaporation mode, the steam outlet is open, the hot water outlet is closed, the electric heating element is turned off, and the output power of the heat pump system is increased;

[0011] If the current steam quality is lower than the set steam quality, determine whether the heat pump system meets the first preset condition;

[0012] If the heat pump system meets the first preset condition, the heat pump steam system is controlled to enter the hot water mode, the steam outlet is closed, the hot water outlet is opened, and the electric heating element is activated.

[0013] Furthermore, if the heat pump steam system is in hot water mode, it also includes:

[0014] Calculate the deviation between the set steam quality and the current steam quality;

[0015] Determine the preset deviation value range corresponding to the deviation value;

[0016] Obtain the target heating power corresponding to the preset deviation value range;

[0017] The target heating power is determined to be the heating power of the electric heating element.

[0018] Furthermore, the heat pump system includes a primary heat pump unit and a secondary heat pump unit. The primary heat pump unit includes a primary compressor, a condenser-evaporator, a primary expansion valve, and a primary evaporator connected in sequence by a second refrigerant pipe. The secondary heat pump unit includes a secondary compressor, a first condenser, a secondary expansion valve, and the condenser-evaporator connected by a first refrigerant pipe. The first refrigerant pipe and the second refrigerant pipe are coupled through the condenser-evaporator for heat exchange.

[0019] The determination of whether the first preset condition is met includes:

[0020] Determine whether the frequency of the primary compressor is at the optimal frequency point.

[0021] Further, determining whether the frequency of the primary compressor is at the optimal frequency point includes:

[0022] The change in heating capacity of the secondary compressor caused by the adjustment of the frequency of the primary compressor, and the change in the total power of the heat pump system during the same period are obtained.

[0023] If the change in heating capacity equals the change in total power, then the current frequency of the primary compressor is determined to be at the optimal frequency point.

[0024] Furthermore, increasing the output power of the heat pump system includes:

[0025] Increase the frequency of the primary compressor;

[0026] When the temperature of the condenser-evaporator exceeds the set temperature difference, the frequency of the secondary compressor is adjusted.

[0027] Furthermore, it also includes:

[0028] Obtain the circulating water flow rate of the water circulation pipeline and the softened water flow rate of the water replenishment pipeline;

[0029] Calculate the first change in the circulating water flow rate, and calculate the second change in the softened water flow rate;

[0030] The frequency of the booster pump and the opening of the water supply valve are adjusted synchronously to make the first change equal to the second change.

[0031] Secondly, the present invention also provides another control method for a heat pump steam system, the heat pump steam system including a heat pump system and a hot water circulation flash evaporation system, wherein the refrigerant pipeline of the heat pump system and the water circulation pipeline of the hot water circulation flash evaporation system are coupled through a first condenser for heat exchange.

[0032] The hot water circulation flash evaporation system includes a booster pump, a three-way shut-off valve, and a flash tank connected sequentially through the water circulation pipeline; the booster pump has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve is installed on the water supply pipeline; the three-way shut-off valve includes a hot water inlet, a steam outlet, and a hot water outlet, the hot water inlet being connected to the outlet of the first condenser through the water circulation pipeline, the steam outlet being connected to the saturated steam zone of the flash tank, and the hot water outlet being connected to the saturated water zone of the flash tank; a steam outlet valve is provided at the top of the flash tank; an electric heating element is provided inside the flash tank; the control method includes the following steps:

[0033] Obtain a steam quality reduction adjustment command;

[0034] Determine whether the heat pump steam system is in flash mode or hot water mode;

[0035] If it is in hot water mode, the steam outlet is closed, the hot water outlet is opened, the electric heating element is activated, and the deviation between the set steam quality and the current steam quality is calculated.

[0036] If the deviation value is less than the preset deviation value, the heating power of the electric heating element is reduced;

[0037] If the deviation value is greater than the preset deviation value, the heat pump steam system is controlled to enter flash steam mode, the steam outlet is opened, the hot water outlet is closed, and the electric heating element is turned off.

[0038] Furthermore, if the heat pump steam system is in flash mode, it also includes:

[0039] Reduce the output power of the heat pump system;

[0040] Determine whether the current steam quality meets the set steam quality.

[0041] Thirdly, the present invention also provides a heat pump steam system control device, wherein the heat pump steam system includes a heat pump system and a hot water circulation flash evaporation system, wherein the refrigerant pipeline of the heat pump system and the water circulation pipeline of the hot water circulation flash evaporation system are coupled through a first condenser for heat exchange; the hot water circulation flash evaporation system includes a booster pump, a three-way shut-off valve and a flash tank connected in sequence through the water circulation pipeline, wherein the booster pump has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve is provided on the water supply pipeline; the three-way shut-off valve includes a hot water inlet, a steam outlet and a hot water outlet, wherein the hot water inlet is connected to the outlet of the first condenser through the water circulation pipeline, the steam outlet is connected to the saturated steam zone of the flash tank, and the hot water outlet is connected to the saturated water zone of the flash tank; a steam outlet valve is provided at the top of the flash tank; an electric heating element is provided inside the flash tank; the device includes:

[0042] The first instruction acquisition module is used to acquire steam quality increase adjustment instructions.

[0043] The first judgment module is used to determine whether the heat pump steam system is in flash mode or hot water mode;

[0044] The first adjustment module is used to open the steam outlet, close the hot water outlet, and close the electric heating element in flash evaporation mode, thereby increasing the output power of the heat pump system.

[0045] The second judgment module is used to determine whether the first preset condition is met if the current steam quality does not meet the set steam quality.

[0046] The mode switching module is used to control the heat pump steam system to enter the hot water mode if a first preset condition is met, in which case the steam outlet is closed, the hot water outlet is opened, and the electric heating element is activated.

[0047] Fourthly, the present invention also provides a controller, comprising:

[0048] At least one computer storage medium and at least one processor;

[0049] The computer storage medium is used to store one or more programs;

[0050] When the one or more programs are executed by the at least one processor, the at least one processor performs the steps of the control method for the heat pump steam system as described in the first and second aspects.

[0051] The control method, device, and controller for a heat pump steam system described in this invention have the following beneficial effects:

[0052] 1. This invention, by installing an electric heating element inside a flash tank and setting both a flash mode and a hot water mode, adjusts various components of the heat pump steam system in flash mode after receiving a steam quality improvement adjustment command. Specifically, it increases the output power of the heat pump system, allowing more steam to be flashed into the flash tank to achieve higher temperatures or pressures. If the steam quality requirements are still not met, it switches to hot water mode, adjusting the power of the electric heating element according to the deviation value to generate steam and ensure the improvement in steam quality is met. Thus, by combining flash mode with hot water mode and utilizing electric heating elements, this invention enables the heat pump system to operate under preset conditions while improving steam quality, thereby improving the overall heating efficiency of the system and maintaining low energy consumption. It has the advantages of high heating efficiency and low energy consumption. Furthermore, this invention simplifies the structure of the heat pump system.

[0053] 2. Furthermore, this invention enables the heat pump system to operate the primary compressor at the optimal frequency point even under high load when the steam quality increases, thereby further saving energy and improving heating efficiency.

[0054] 3. This invention obtains a steam quality reduction adjustment command, determines the operating mode of the heat pump steam system, and then adjusts the power of the heat pump system or the power of the electric heating element. The two work together to adjust and stably meet the steam quality requirements.

[0055] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the structure of a heat pump steam system according to an embodiment of the present invention;

[0057] Figure 2 This is a flowchart of a control method for a heat pump steam system according to the present invention;

[0058] Figure 3 This is a flowchart of a control method for a heat pump steam system according to the present invention;

[0059] Figure 4 This is a flowchart of a control method for a heat pump steam system according to an embodiment of the present invention;

[0060] Figure 5 This is a flowchart of a control method for a heat pump steam system according to the present invention;

[0061] Figure 6 This is a flowchart of a control method for a heat pump steam system according to the present invention;

[0062] Figure 7 This is a flowchart of a control method for a heat pump steam system according to an embodiment of the present invention;

[0063] Figure 8 This is a schematic diagram of the structure of a control device for a heat pump steam system according to an embodiment of the present invention.

[0064] Reference numerals: heat pump system 100, primary compressor 110, condenser-evaporator 120, primary expansion valve 130, primary evaporator 140, secondary compressor 210, first condenser 220, secondary expansion valve 230;

[0065] Hot water circulation flash evaporation system 300, water supply valve 310, pressurization pump 330, three-way shut-off valve 350, steam outlet 351, hot water outlet 352, hot water inlet 353, flash tank 360, electric heating element 370, steam outlet valve 380;

[0066] The control device 800, the first instruction acquisition module 810, the first judgment module 820, the first adjustment module 830, the second judgment module 840, and the first mode switching module 850 are included. Detailed Implementation

[0067] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0068] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0070] To address the technical problems mentioned in the background section, this application provides a control method for a heat pump steam system. The heat pump steam system described in this application is used to generate steam and output steam of a specific quality, such as... Figure 1 As shown, in one embodiment, the heat pump steam system includes a heat pump system 100 and a hot water circulation flash evaporation system 300. The refrigerant pipeline of the heat pump system 100 and the water circulation pipeline of the hot water circulation flash evaporation system 300 are coupled through a first condenser 220 for heat exchange. The hot water circulation flash evaporation system 300 includes a booster pump 330, a three-way shut-off valve 350, and a flash tank 360 connected in sequence through the water circulation pipeline. The booster pump 330 has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve 310 is installed on the water supply pipeline. The three-way shut-off valve 350 includes a hot water inlet 353, a steam outlet 351, and a hot water outlet 352. The hot water inlet 353 is connected to the outlet of the first condenser 220 through the water circulation pipeline, the steam outlet 351 is connected to the saturated steam zone of the flash tank 360, and the hot water outlet 352 is connected to the saturated water zone of the flash tank 360. A steam outlet valve 380 is provided at the top of the flash tank 360. The flash tank 360 is equipped with an electric heating element 370. In this embodiment, the heat pump system 100 may be a single-stage heat pump system or a cascade heat pump system.

[0071] In a specific example, such as Figure 2 As shown in the embodiments of this application, a control method for a heat pump steam system includes the following steps:

[0072] S201: Obtain steam quality improvement adjustment command;

[0073] S202: Determine whether the heat pump steam system is in flash mode or hot water mode;

[0074] S203: If it is in flash mode, the steam outlet 351 is opened, the hot water outlet 352 is closed, the electric heating element 370 is turned off, and the output power of the heat pump system 100 is increased.

[0075] S204: If the current steam quality is lower than the set steam quality, determine whether the heat pump system meets the first preset condition;

[0076] S205: If the heat pump system meets the first preset condition, the heat pump steam system is controlled to enter the hot water mode, the steam outlet 351 is closed, the hot water outlet 352 is opened, and the electric heating element 370 is started.

[0077] One method for obtaining a steam quality increase adjustment command is to obtain the steam quality requirement directly input by the user, compare the user-input steam quality with the current steam quality, and generate a steam quality increase adjustment command if the set steam quality is greater than the current steam quality. Alternatively, it can obtain a steam quality increase command directly input by the user, which is associated with a fixed steam quality increase amount, and then generate a steam quality increase adjustment command based on this increase amount.

[0078] The output power adjustment method differs for different heat pump systems 100. For a single-stage heat pump system, the output power can be increased by increasing the compressor frequency. For a cascade heat pump system, the primary or secondary compressors can be adjusted separately to increase the overall system output power. Furthermore, increasing the output power of the heat pump system 100 aims to raise the heat exchange temperature of the first condenser 220. Increasing the compressor frequency of the heat pump system 100 increases the temperature and pressure of the output refrigerant, leading to an increase in the refrigerant-side temperature of the first condenser 220, thereby raising its heat exchange temperature.

[0079] Optionally, the first preset condition may be that the heat pump system 100 reaches its optimal operating efficiency, or the compressor of the heat pump system 100 reaches its optimal operating frequency, or the heat pump system 100 and its related components reach a limiting protection condition (high temperature / high pressure limitation), etc. For different types of heat pump systems 100, their optimal operating efficiency, optimal operating frequency, and limiting protection conditions can be set separately, or they can be set using conventional technical methods.

[0080] The control method of a heat pump steam system described in this embodiment of the invention involves setting an electric heating element 370 in a flash tank 360 and setting a flash mode and a hot water mode. After receiving a steam quality improvement adjustment command, the various components of the heat pump steam system in flash mode are adjusted. Specifically, the output power of the heat pump system 100 is increased to allow more steam to be flashed into the flash tank, achieving a higher temperature or pressure. If the steam quality requirements are still not met, the system switches to hot water mode, adjusting the power of the electric heating element 370 according to the deviation value to generate steam and ensure that the increased steam quality is met. Thus, by combining flash mode with hot water mode and utilizing the electric heating element 370, this invention enables the heat pump system 100 to operate under preset operating conditions while improving steam quality, thereby improving the heating efficiency of the entire system and maintaining a low energy consumption state. It has the advantages of high heating efficiency and low energy consumption. Furthermore, this invention simplifies the structure of the heat pump system 100.

[0081] Furthermore, such as Figure 3 As shown, after receiving the steam demand increase adjustment command, if the heat pump steam system is in hot water mode, or after controlling the heat pump steam system to enter hot water mode under the first preset condition, the following steps are also included:

[0082] S301: Calculate the deviation between the set steam quality and the current steam quality;

[0083] S302: Determine the preset deviation value range corresponding to the deviation value;

[0084] S303: Obtain the target heating power corresponding to the preset deviation value range;

[0085] S304: The target heating power is determined to be the heating power of the electric heating element 370.

[0086] Specifically, the steam quality setting can be an increase in steam temperature or steam pressure. The deviation between the set steam quality and the current steam quality is calculated using the formula △=(Tset - Tcurrent) or △=(Pset - Pcurrent), where Tset is the set steam temperature, Tcurrent is the current steam temperature, Pset is the set steam pressure, and Pcurrent is the current steam pressure.

[0087] The heating power of the electric heating element 370 is positively correlated with the deviation value. This correlation can be linear or multiple different levels can be preset for the heating power, with different levels corresponding to different deviation values ​​within different ranges.

[0088] Preferably, the preset deviation value range can be divided into a first deviation value range, a second deviation value range, and a third deviation value range based on the influence of the electric heating element 370 on the deviation value. When the deviation value is within the first deviation value range, a weak electric heating mode is activated, meaning the power of the electric heating element 370 is 50% of its rated power, and the duty cycle of the electric heating is increased to maintain heat balance through intermittent heating. When the deviation value is within the second deviation value range, a strong electric heating mode is activated, meaning the power of the electric heating element 370 is at its rated power, and the duty cycle of the electric heating is increased to maintain heat balance through intermittent heating. When the deviation value is within the third deviation value range, if the set steam quality is too high and deviates from the actual unit operating adjustment range, the system will report an error and return to the set point for user inspection. Optionally, the first deviation value range is less than 15℃ or less than 0.25MPa; the second deviation value range is 15℃ to 50℃ or 0.25MPa to 0.6MPa; and the third deviation value range is greater than 50℃ or greater than 0.6MPa.

[0089] In an optional example, when the electric heating element 370 is turned on, the starting power is divided into a weak heating mode and a strong heating mode. The subsequent adjustment method is to change the duty cycle τ of the electric heating element 370. The specific formula for calculating the duty cycle τ is τ = t_electric_heating / T_cycle, that is, the ratio of the start-up time of the electric heating element 370 to the cycle time within a unit cycle. The initial duty cycle of the electric heating element 370 is 0.5, and after starting, the duty cycle is adjusted between 0.5 and 1 according to the adjustment situation.

[0090] In a preferred example, such as Figure 1 As shown, if the heat pump system 100 is a cascade heat pump system, then the heat pump system 100 includes a primary heat pump unit and a secondary heat pump unit. The primary heat pump unit includes a primary compressor 110, a condenser-evaporator 120, a primary expansion valve 130, and a primary evaporator 140 connected sequentially by a second refrigerant pipe. The secondary heat pump unit includes a secondary compressor 210, a first condenser 220, a secondary expansion valve 230, and a condenser-evaporator 120 connected by a first refrigerant pipe. The first refrigerant pipe and the second refrigerant pipe are coupled through the condenser-evaporator 120 for heat exchange. Preferably, whether the first preset condition is met specifically includes:

[0091] Determine whether the frequency of the primary compressor 110 is at the optimal frequency point.

[0092] Specifically, determining whether the frequency of the primary compressor 110 is at the optimal frequency point includes:

[0093] The change in heating capacity of the secondary compressor 210 caused by the adjustment of the frequency of the primary compressor 110, and the change in the total power of the heat pump system 100 during the same period are obtained.

[0094] If the change in heating capacity equals the change in total power, then the current frequency of the primary compressor 110 is determined to be at the optimal frequency point.

[0095] Preferably, the change in heating capacity equals the change in total power, expressed by the formula dQ / dfc1=dW / dfc1, where fc1 is the frequency of the primary compressor, Q is the heating capacity of the secondary compressor, and W is the total power of the primary and secondary systems.

[0096] Furthermore, in the above example, when adjusting and increasing the output power of the heat pump system 100, if the heat pump system 100 is a cascade heat pump system, it also includes:

[0097] Increase the frequency of the primary compressor 110;

[0098] When the temperature of the condenser-evaporator 120 exceeds the set temperature difference, the frequency of the secondary compressor 210 is adjusted.

[0099] Preferably, the set temperature difference is 5 degrees Celsius, meaning that when the temperature of the condenser evaporator 240 increases or decreases by more than 5 degrees, the secondary compressor starts frequency conversion adjustment.

[0100] The examples above also include:

[0101] Obtain the circulating water flow rate of the water circulation pipeline and the softened water flow rate of the water supply pipeline;

[0102] Calculate the first change in circulating water flow rate, and calculate the second change in softened water flow rate;

[0103] The frequency of the booster pump 330 and the opening of the water supply valve 310 are adjusted synchronously to make the first change equal to the second change.

[0104] This embodiment ensures that the water supply pipeline replenishes the missing water in the circulating water in a timely manner by making the first change equal to the second change, thus preventing the pressure in the circulating water from failing to reach the predetermined pressure and guaranteeing the quality of steam output.

[0105] In a specific embodiment, such as Figure 4 As shown, the control method of the heat pump steam system in the above embodiment is applied to... Figure 1 The heat pump steam system shown, wherein the heat pump system 100 employs a cascade heat pump, includes the following steps:

[0106] S401: Obtain steam quality improvement adjustment command;

[0107] S402: Determine the current operating mode of the heat pump steam system, including hot water mode and flash steam mode; if it is flash steam mode, steam outlet 351 is open, hot water outlet 352 is closed, and electric heating element 370 is closed; if it is hot water mode, steam outlet 351 is closed, hot water outlet 352 is open, electric heating element 370 is started, and step S406 is directly executed to determine the deviation between the set steam quality and the current steam quality.

[0108] S403: If it is flash evaporation mode, increase the output power of heat pump system 100. Specifically, first increase the frequency of primary inverter. When the temperature of condenser evaporator 240 increases by more than 5°C, start to increase the frequency of secondary compressor. Adjust the inverter of primary compressor and secondary compressor to make the heating capacity of primary and secondary systems approximately equal.

[0109] S404: Determine whether the current steam quality meets the set steam quality. If yes, end the operation.

[0110] S405: If not, determine whether the primary compressor has reached the optimal frequency point. If the optimal frequency point has not been reached, return to step S403 to continue adjusting the output power of the heat pump system 100. If the optimal frequency point has been reached, the system switches to hot water mode and executes step S406.

[0111] S406: Determine the deviation between the set steam quality and the current steam quality, i.e., Δ = set - T current, or Δ = P set - P current;

[0112] S407: When Δ < 15℃ or Δ < 0.25MPa, the weak electric heating mode is turned on, the electric heating power is 50% of the rated power, and the duty cycle is increased to maintain heat balance through intermittent heating.

[0113] S408: When 15℃≤Δ<50℃ or 0.25MPa≤Δ<0.6MPa, the high-power electric heating mode is turned on, the electric heating power is the rated power, and the duty cycle is increased to maintain heat balance through intermittent heating.

[0114] S409: When Δ≥50℃ or Δ≥0.6MPa, the set steam quality is too high and deviates from the actual unit operating adjustment range. At this time, the unit reports an error and returns to the set point for user inspection.

[0115] S410: Detect the steam quality at steam outlet 380. When the set steam quality is reached, the adjustment process ends. When the set steam quality is not reached, return to step S406 to determine the deviation between the current steam quality and the set steam quality. Continue to increase the heating time of electric heating element 370 until the set steam quality is reached, at which point the adjustment process ends.

[0116] In another specific example, such as Figure 5 As shown in the embodiment of the invention, another control method for a heat pump steam system includes the following steps:

[0117] S501: Obtain a steam demand quality reduction adjustment command;

[0118] S502: Determine whether the heat pump steam system is in flash mode or hot water mode;

[0119] S503: If it is hot water mode, steam outlet 351 is closed, hot water outlet 352 is opened, electric heating element 370 is started, and the deviation value between the set steam quality and the current steam quality is calculated.

[0120] S504: If the deviation value is less than the preset deviation value, reduce the heating power of the electric heating element 370;

[0121] S505: If the deviation value is greater than the preset deviation value, the heat pump steam system is controlled to enter the flash steam mode, the steam outlet 351 is opened, the hot water outlet 352 is closed, and the electric heating element 370 is turned off.

[0122] Specifically, in the above example, if the heat pump steam system is in flash mode or the heat pump steam system is controlled to enter flash mode, the output power of the heat pump system 100 is reduced. If it is determined that the current steam quality has not yet reached the set steam quality, the compressor frequency is reduced again until the set steam demand is reached, and the adjustment process ends.

[0123] Preferably, the calculation method for the deviation between the set steam quality and the current steam quality in step S503 is the same as the calculation method in the example above.

[0124] Furthermore, such as Figure 6 As shown, if the heat pump steam system is in flash mode, the following steps are also included:

[0125] S601: Reduce the output power of the heat pump system;

[0126] S602: Determine whether the current steam quality meets the set steam quality.

[0127] Preferably, in the above example, the preset deviation value is set to 20℃ or 0.2MPa.

[0128] In a specific embodiment, such as Figure 7 As shown, the control method of the heat pump steam system in the above embodiment is applied to... Figure 1 The heat pump steam system shown, wherein the heat pump system 100 employs a cascade heat pump, includes the following steps:

[0129] S701: Obtain steam quality reduction adjustment command;

[0130] S702: Determine the current operating mode of the heat pump steam system, including hot water mode and flash steam mode; if it is flash steam mode, steam outlet 351 is open, hot water outlet 352 is closed, and electric heating element 370 is closed; if it is hot water mode, steam outlet 351 is closed, hot water outlet 352 is open, and electric heating element 370 is started.

[0131] S703: If it is flash evaporation mode, reduce the output power of heat pump system 100. Specifically, first reduce the frequency of secondary compressor. When the temperature of condenser evaporator 220 decreases by more than 5°C, start to reduce the frequency of primary inverter. Adjust the inverter of primary compressor and secondary compressor to make the heating capacity of primary and secondary systems approximately equal. Then directly execute step S707.

[0132] S704: If it is hot water mode, determine the deviation between the set steam quality and the current steam quality, i.e., △=set - Tcurrent, or △=Pset - Pcurrent;

[0133] S705: When Δ>20℃ or Δ>0.2MPa, the set steam quality deviates significantly from the current steam quality. The system switches to flash steam mode and returns to step S703.

[0134] S706: When Δ≤20℃ or Δ≤0.2MPa, if the deviation between the set steam quality and the current steam quality is small, then reduce the duty cycle of the electric heating element 370;

[0135] S707: Detect the steam quality at steam outlet 380. If the set steam quality is reached, the adjustment process ends. If the set steam quality is not reached, return to step S703 or step S706 until the set steam quality is reached, at which point the adjustment process ends.

[0136] Corresponding to the above-described control method for a heat pump steam system, this application also provides a heat pump steam system control device. Specifically, the heat pump steam system includes a heat pump system 100 and a hot water circulation flash evaporation system 300. The refrigerant pipeline of the heat pump system 100 and the water circulation pipeline of the hot water circulation flash evaporation system 300 are coupled through a first condenser 220 for heat exchange. The hot water circulation flash evaporation system 300 includes a booster pump 330, a three-way shut-off valve 350, and a flash tank 360 connected in sequence through the water circulation pipeline. The booster pump 330 is equipped with a front end... A water supply pipe is connected to the water circulation pipe, and a water supply valve 310 is installed on the water supply pipe; a three-way shut-off valve 350 includes a hot water inlet 353, a steam outlet 351, and a hot water outlet 352. The hot water inlet 353 is connected to the outlet of the first condenser 220 through the water circulation pipe, the steam outlet 351 is connected to the saturated steam zone of the flash tank 360, and the hot water outlet 352 is connected to the saturated water zone of the flash tank 360; a steam outlet valve 380 is provided on the top of the flash tank 360; an electric heating element 370 is provided inside the flash tank 360. Figure 8 As shown, the control device 800 includes:

[0137] The first instruction acquisition module 810 is used to acquire steam quality increase adjustment instructions;

[0138] The first judgment module 820 is used to determine whether the heat pump steam system is in flash mode or hot water mode.

[0139] The first regulating module 830 is used to open the steam outlet 351 and close the hot water outlet 352 in flash mode, thereby increasing the output power of the heat pump system.

[0140] The second judgment module 840 is used to determine whether the heat pump system meets the first preset condition if the current steam quality is lower than the set steam quality.

[0141] The first mode switching module 850 is used to control the heat pump steam system to enter the hot water mode if the first preset condition is met, the steam outlet 351 is closed, the hot water outlet 352 is opened, and the electric heating element 370 is started.

[0142] In one exemplary embodiment, the control device 800 further includes:

[0143] The first calculation module is used to calculate the deviation between the set steam quality and the current steam quality after the heat pump steam system enters the hot water mode.

[0144] The third judgment module is used to determine the preset deviation value range corresponding to the deviation value;

[0145] The second instruction acquisition module is used to acquire the target heating power corresponding to the preset deviation value range;

[0146] The second adjustment module is used to determine the target heating power as the heating power of the electric heating element 370.

[0147] In an exemplary embodiment, the primary heat pump unit includes a primary compressor 110, a condenser-evaporator 120, a primary expansion valve 130, and a primary evaporator 140 connected in sequence by a second refrigerant pipe; the secondary heat pump unit includes a secondary compressor 210, a first condenser 220, a secondary expansion valve 230, and a condenser-evaporator 120 connected by a first refrigerant pipe; the first refrigerant pipe and the second refrigerant pipe are coupled through the condenser-evaporator 120 for heat exchange; the second determination module 840 includes:

[0148] The first judgment unit is used to determine whether the frequency of the primary compressor 110 is at the optimal frequency point.

[0149] In one exemplary embodiment, the first determination unit includes:

[0150] The first instruction acquisition subunit is used to acquire the change in heating capacity of the secondary compressor 210 caused by the adjustment of the frequency of the primary compressor 110, as well as the change in the total power of the heat pump system 100 during the same period.

[0151] The first judgment subunit is used to determine whether the change in heating capacity is equal to the change in total power, and then to determine whether the current frequency of the primary compressor 110 is at the optimal frequency point.

[0152] In one exemplary embodiment, the first adjustment module 830 includes:

[0153] The first regulating unit is used to increase the frequency of the primary compressor 110;

[0154] The second regulating unit is used to adjust the frequency of the secondary compressor 210 when the temperature of the condenser-evaporator 120 exceeds the set temperature difference.

[0155] In one exemplary embodiment, the control device 800 further includes:

[0156] The flow acquisition module is used to acquire the circulating water flow rate of the water circulation pipeline and the softened water flow rate of the water supply pipeline;

[0157] The flow change calculation module is used to calculate the first change in circulating water flow and the second change in softened water flow.

[0158] The first synchronous adjustment module is used to synchronously adjust the frequency of the booster pump 330 and the opening of the water supply valve 310 so that the first change is equal to the second change.

[0159] In one exemplary embodiment, the control device 800 further includes:

[0160] The second instruction acquisition module is used to acquire steam demand quality reduction adjustment instructions.

[0161] The fourth judgment module is used to determine whether the heat pump steam system is in flash mode or hot water mode;

[0162] The second calculation module is used to calculate the deviation between the set steam quality and the current steam quality when the steam outlet 351 is closed, the hot water outlet 352 is open, and the electric heating element 370 is started in hot water mode.

[0163] The third adjustment module is used to reduce the heating power of the electric heating element 370 if the deviation value is less than the preset deviation value.

[0164] The second mode switching module is used to control the heat pump steam system to enter flash steam mode if the deviation value is greater than the preset deviation value, thereby opening the steam outlet 351, closing the hot water outlet 352, and turning off the electric heating element 370.

[0165] In one exemplary embodiment, the control device 800 further includes:

[0166] The fourth adjustment module is used to reduce the output power of the heat pump system;

[0167] The fifth judgment module is used to determine whether the current steam quality meets the set steam quality.

[0168] Corresponding to the control method of the heat pump steam system described above, this application also provides a controller, including:

[0169] At least one computer storage medium and at least one processor;

[0170] Computer storage media used to store one or more programs;

[0171] When one or more programs are executed by at least one processor, the at least one processor implements the steps of the control method for a heat pump steam system as described above.

[0172] The control method, apparatus, and controller for a heat pump steam system described in this invention have the following beneficial effects:

[0173] 1. This invention, by installing an electric heating element inside a flash tank and setting both a flash mode and a hot water mode, adjusts various components of the heat pump steam system in flash mode after receiving a steam quality improvement adjustment command. Specifically, it increases the output power of the heat pump system, allowing more steam to be flashed into the flash tank to achieve higher temperatures or pressures. If the steam quality requirements are still not met, it switches to hot water mode, adjusting the power of the electric heating element according to the deviation value to generate steam and ensure the improvement in steam quality is met. Thus, by combining flash mode with hot water mode and utilizing electric heating elements, this invention enables the heat pump system to operate under preset conditions while improving steam quality, thereby improving the overall heating efficiency of the system and maintaining low energy consumption. It has the advantages of high heating efficiency and low energy consumption. Furthermore, this invention simplifies the structure of the heat pump system.

[0174] 2. Furthermore, this invention enables the heat pump system to operate the primary compressor at the optimal frequency point even under high load when the steam quality increases, thereby further saving energy and improving heating efficiency.

[0175] 3. This invention obtains a steam quality reduction adjustment command, determines the operating mode of the heat pump steam system, and then adjusts the power of the heat pump system or the power of the electric heating element. The two work together to adjust and stably meet the steam quality requirements.

[0176] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and the present invention also intends to include these modifications and variations.

Claims

1. A control method for a heat pump steam system, characterized in that... ； The heat pump steam system includes a heat pump system and a hot water circulation flash evaporation system. The refrigerant pipeline of the heat pump system and the water circulation pipeline of the hot water circulation flash evaporation system are coupled through a first condenser (220) for heat exchange. The hot water circulation flash evaporation system includes a booster pump (330), a three-way shut-off valve (350), and a flash tank (360) connected in sequence through the water circulation pipeline; the booster pump (330) has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve (310) is provided on the water supply pipeline; the three-way shut-off valve (350) includes a hot water inlet (353), a steam outlet (351), and a hot water outlet (352); the hot water inlet (353) is connected to the outlet of the first condenser (220) through the water circulation pipeline, the steam outlet (351) is connected to the saturated steam zone of the flash tank (360), and the hot water outlet (352) is connected to the saturated water zone of the flash tank (360); a steam outlet valve (380) is provided at the top of the flash tank (360); and an electric heating element (370) is provided inside the flash tank (360). The control method includes the following steps: Obtain steam quality improvement adjustment instructions; Determine whether the heat pump steam system is in flash mode or hot water mode; If it is in flash mode, the steam outlet (351) is open, the hot water outlet (352) is closed, the electric heating element (370) is closed, and the output power of the heat pump system is increased; If the current steam quality is lower than the set steam quality, determine whether the heat pump system meets the first preset condition; If the heat pump system meets the first preset condition, the heat pump steam system is controlled to enter the hot water mode, the steam outlet (351) is closed, the hot water outlet (352) is opened, and the electric heating element (370) is started. The first preset condition is that the heat pump system reaches its optimal operating efficiency, or the compressor of the heat pump system reaches its optimal operating frequency, or the heat pump system reaches its limiting protection condition.

2. The control method for a heat pump steam system according to claim 1, characterized in that, If the heat pump steam system is in hot water mode, it also includes: Calculate the deviation between the set steam quality and the current steam quality; Determine the preset deviation value range corresponding to the deviation value; Obtain the target heating power corresponding to the preset deviation value range; The target heating power is determined to be the heating power of the electric heating element (370).

3. The control method for a heat pump steam system according to claim 2, characterized in that: The heat pump system includes a primary heat pump unit and a secondary heat pump unit. The primary heat pump unit includes a primary compressor (110), a condenser-evaporator (120), a primary expansion valve (130), and a primary evaporator (140) connected in sequence by a second refrigerant pipe. The secondary heat pump unit includes a secondary compressor (210), a first condenser (220), a secondary expansion valve (230), and the condenser-evaporator (120) connected by a first refrigerant pipe. The first refrigerant pipe and the second refrigerant pipe are coupled through the condenser-evaporator (120) for heat exchange. The determination of whether the first preset condition is met includes: Determine whether the frequency of the primary compressor (110) is at the optimal frequency point.

4. The control method for a heat pump steam system according to claim 3, characterized in that, Determining whether the frequency of the primary compressor (110) is at the optimal frequency point includes: The change in heating capacity of the secondary compressor (210) caused by the adjustment of the frequency of the primary compressor (110), and the change in the total power of the heat pump system during the same period are obtained. If the change in heating capacity is equal to the change in total power, then the current frequency of the primary compressor (110) is determined to be at the optimal frequency point.

5. The control method for a heat pump steam system according to claim 3, characterized in that, Increasing the output power of the heat pump system includes: Increase the frequency of the primary compressor (110); When the temperature of the condenser-evaporator (120) exceeds the set temperature difference, the frequency of the secondary compressor (210) is adjusted.

6. The control method for a heat pump steam system according to claim 1, characterized in that, Also includes: Obtain the circulating water flow rate of the water circulation pipeline and the softened water flow rate of the water replenishment pipeline; Calculate the first change in the circulating water flow rate, and calculate the second change in the softened water flow rate; The frequency of the booster pump (330) and the opening of the water supply valve (310) are adjusted synchronously so that the first change is equal to the second change.

7. A control method for a heat pump steam system, characterized in that... ； The heat pump steam system includes a heat pump system and a hot water circulation flash evaporation system. The refrigerant pipeline of the heat pump system and the water circulation pipeline of the hot water circulation flash evaporation system are coupled through a first condenser (220) for heat exchange. The hot water circulation flash evaporation system includes a booster pump (330), a three-way shut-off valve (350), and a flash tank (360) connected sequentially through the water circulation pipeline; the booster pump (330) has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve (310) is provided on the water supply pipeline; the three-way shut-off valve (350) includes a hot water inlet (353), a steam outlet (351), and a hot water outlet (352); the hot water inlet (353) is connected to the outlet of the first condenser (220) through the water circulation pipeline, the steam outlet (351) is connected to the saturated steam zone of the flash tank (360), and the hot water outlet (352) is connected to the saturated water zone of the flash tank (360); a steam outlet valve (380) is provided at the top of the flash tank (360); an electric heating element (370) is provided inside the flash tank (360); the control method includes the following steps: Obtain a steam quality reduction adjustment command; Determine whether the heat pump steam system is in flash mode or hot water mode; If it is hot water mode, the steam outlet (351) is closed, the hot water outlet (352) is opened, the electric heating element (370) is activated, and the deviation value between the set steam quality and the current steam quality is calculated; If the deviation value is less than the preset deviation value, the heating power of the electric heating element (370) is reduced; If the deviation value is greater than the preset deviation value, the heat pump steam system is controlled to enter the flash steam mode, the steam outlet (351) is opened, the hot water outlet (352) is closed, and the electric heating element (370) is turned off.

8. The control method for a heat pump steam system according to claim 7, characterized in that, If the heat pump steam system is in flash mode, it also includes: Reduce the output power of the heat pump system; Determine whether the current steam quality meets the set steam quality.

9. A control device for a heat pump steam system, characterized in that, The heat pump steam system includes a heat pump system and a hot water circulation flash evaporation system. The refrigerant pipeline of the heat pump system and the water circulation pipeline of the hot water circulation flash evaporation system are coupled through a first condenser (220) for heat exchange. The hot water circulation flash evaporation system includes a booster pump (330), a three-way shut-off valve (350), and a flash tank (360) connected in sequence through the water circulation pipeline. The booster pump (330) has a water supply pipeline connected to the water circulation pipeline at its front end, and a water supply valve (310) is installed on the water supply pipeline. The three-way shut-off valve (350) includes a hot water supply valve. The device comprises an inlet (353), a steam outlet (351), and a hot water outlet (352). The hot water inlet (353) is connected to the outlet of the first condenser (220) via the water circulation pipeline. The steam outlet (351) is connected to the saturated steam zone of the flash tank (360), and the hot water outlet (352) is connected to the saturated water zone of the flash tank (360). A steam outlet valve (380) is provided at the top of the flash tank (360). An electric heating element (370) is provided inside the flash tank (360). The device includes: The first instruction acquisition module is used to acquire steam quality increase adjustment instructions. The first judgment module is used to determine whether the heat pump steam system is in flash mode or hot water mode; The first regulating module is used to open the steam outlet (351), close the hot water outlet (352), and close the electric heating element (370) in flash evaporation mode, thereby increasing the output power of the heat pump system. The second judgment module is used to determine whether the heat pump system meets the first preset condition if the current steam quality is lower than the set steam quality. The mode switching module is used to control the heat pump steam system to enter the hot water mode if the heat pump system meets the first preset condition, the steam outlet (351) is closed, the hot water outlet (352) is opened, and the electric heating element (370) is started. The first preset condition is that the heat pump system reaches its optimal operating efficiency, or the compressor of the heat pump system reaches its optimal operating frequency, or the heat pump system reaches its limiting protection condition.

10. A controller, characterized in that, include: At least one computer storage medium and at least one processor; The computer storage medium is used to store one or more programs; When the one or more programs are executed by the at least one processor, the at least one processor implements the steps of the control method for a heat pump steam system as described in any one of claims 1 to 9.

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