Air source heat pump water heater negative price control method and device

Abstract

The application relates to a negative electricity price control method and device of an air source heat pump water heater, and relates to the technical field of heat pump control. The method comprises the following steps: collecting an electricity price state signal output by an electricity network in real time; determining the electricity price state of the current electricity network according to the duration of the electricity price state signal; when it is determined that the electricity price state of the electricity network is a negative electricity price triggering state, the air source heat pump water heater enters a negative electricity price control mode, in the negative electricity price control mode, an auxiliary electric heating module of the air source heat pump water heater is started, and the hot water target temperature of a water tank of the air source heat pump water heater is set to the highest preset temperature; when it is determined that the electricity price state of the electricity network is a normal electricity price state, a normal control mode is entered, and the air source heat pump water heater is controlled to operate according to a normal target temperature. The application can filter the jitter of the electricity network signal and realize the consumption of surplus electricity of the electricity network in the negative electricity price scenario.

Description

Technical Field

[0001] This application relates to the field of heat pump control technology, and in particular to a method and apparatus for controlling negative electricity prices in an air source heat pump water heater. Background Technology

[0002] As the proportion of global renewable energy generation increases, some countries have introduced negative electricity pricing mechanisms to encourage users to increase electricity consumption and absorb surplus power during periods of electricity surplus. Air source heat pump water heaters, as high-power heating devices, are very suitable as a power grid absorption terminal. However, existing control logic primarily aims at energy conservation and consumption reduction, prioritizing heat pump heating and avoiding auxiliary electric heating, and shutting down only after the water temperature reaches the normal target temperature. This design has the following objective shortcomings when facing negative electricity pricing scenarios: First, the existing control logic is limited by energy-saving design and cannot actively increase power consumption during periods of negative electricity prices. For example, it cannot actively turn on auxiliary electric heating or exceed the conventional water temperature limit for deep energy storage, which makes the equipment unable to effectively assist the grid in absorbing surplus power and causes users to miss the opportunity to obtain subsidies.

[0003] Secondly, the electricity price status signals transmitted by the power grid are highly susceptible to interference during transmission, resulting in brief fluctuations. Existing equipment lacks signal recognition and anti-jitter mechanisms, and directly following the signal's actions can easily lead to frequent start-ups and shutdowns of generating units, severely impacting equipment lifespan and even causing damage.

[0004] Third, existing equipment already has multiple control modes. When external power grid signals are introduced, the lack of a reasonable priority scheduling mechanism and safety fallback logic can easily lead to conflicts in the control system. Summary of the Invention

[0005] In view of the above problems, this application provides a negative electricity price control method and device for an air source heat pump water heater. By determining the negative electricity price state based on the duration of the signal to filter signal jitter, and forcibly activating the auxiliary electric heating module after triggering and setting the water tank temperature to the highest preset temperature, the method achieves both stable equipment operation and maximizing the utilization of surplus power from the power grid.

[0006] In a first aspect, embodiments of this application provide a method for controlling negative electricity prices in an air source heat pump water heater, the method comprising the following steps: Real-time acquisition of electricity price status signals output from the power grid side; The current electricity price status of the power grid is determined by judging the status based on the duration of the electricity price status signal. When the power grid's electricity price status is determined to be in a negative electricity price trigger state, the air source heat pump water heater enters the negative electricity price control mode. In the negative electricity price control mode, the auxiliary electric heating module of the air source heat pump water heater is turned on, and the target temperature of the hot water in the water tank of the air source heat pump water heater is set to the highest preset temperature. When the power grid's electricity price is determined to be at a normal electricity price level, the air source heat pump water heater enters a normal control mode, in which the air source heat pump water heater is controlled to operate at a normal target temperature.

[0007] In one embodiment, the electricity price status signal is a dry contact switching signal; the step of real-time acquisition of the electricity price status signal output from the grid side includes: The closed or open state of the dry contact switch signal is collected in real time at a preset sampling period.

[0008] In one embodiment, the step of determining the state based on the duration of the electricity price status signal includes: When the duration of the collected dry contact switch signal in the closed state reaches a first preset threshold, the electricity price state of the power grid is determined to be the negative electricity price trigger state. When the duration of the collected dry contact switch signal being in the disconnected state reaches the second preset threshold, the electricity price status of the power grid is determined to be the normal electricity price status.

[0009] In one embodiment, the step of determining the state based on the duration of the electricity price state signal further includes: If, within a continuous preset determination period, the duration for which the collected dry contact switch signal is in a closed state does not reach the first preset threshold, and the duration for which it is in an open state does not reach the second preset threshold, then the electricity price status of the power grid is determined to be an abnormal signal status. When the power grid's electricity price status is determined to be in the abnormal signal state, the air source heat pump water heater is controlled to maintain the normal control mode, and the fault alarm operation corresponding to the electricity price status signal is disabled.

[0010] In one embodiment, the negative electricity price control method further includes an operation mode switching step: If, during the operation of the air source heat pump water heater in the negative electricity price control mode, the duration for which the collected dry contact switch signal remains in the open state reaches the second preset threshold, then the negative electricity price control mode will be exited and the system will switch to the normal control mode. If, during the operation of the air source heat pump water heater in the conventional control mode, the duration for which the collected dry contact switch signal remains in a closed state reaches the first preset threshold, then the system switches to the negative electricity price control mode.

[0011] In one embodiment, the air source heat pump water heater is further preset with a rapid heating control mode and a power restriction control mode; the execution priority of the negative electricity price control mode, the rapid heating control mode, and the power restriction control mode decreases in that order.

[0012] In one embodiment, under the negative electricity price control mode, the negative electricity price control method further includes: The real-time water temperature, compressor operating frequency, and operating status parameters of the air source heat pump water heater are obtained. When the real-time water temperature reaches the maximum preset temperature, the auxiliary electric heating module and the heat pump system of the air source heat pump water heater are controlled to stop. When the compressor operating frequency reaches the highest frequency threshold, frequency reduction or frequency limiting control operation is performed. When the operating status parameters meet the preset protection trigger conditions, the corresponding safety shutdown operation is executed.

[0013] In one embodiment, after the heat pump system of the auxiliary electric heating module and the air source heat pump water heater is shut down, the method further includes: when the real-time water temperature is detected to drop to a preset restart temperature threshold, controlling the auxiliary electric heating module and the heat pump system to restart; wherein the restart temperature threshold is less than the highest preset temperature.

[0014] In one embodiment, the auxiliary electric heating module is an electric heating tube or a PTC heater; in the negative electricity price control mode, the auxiliary electric heating module is controlled to start and operate synchronously with the heat pump system of the air source heat pump water heater.

[0015] Secondly, embodiments of this application provide a negative electricity price control device for an air source heat pump water heater, which applies a negative electricity price control method for an air source heat pump water heater as described in any embodiment of the first aspect. The negative electricity price control device includes: The signal acquisition module is used to acquire the electricity price status signal output by the power grid side in real time; The status determination module is used to determine the current electricity price status of the power grid based on the duration of the electricity price status signal. The negative electricity price control module is used to control the air source heat pump water heater to enter the negative electricity price control mode when the electricity price status of the power grid is determined to be a negative electricity price trigger state. In the negative electricity price control mode, the auxiliary electric heating module of the air source heat pump water heater is turned on, and the target temperature of the hot water in the water tank of the air source heat pump water heater is set to the highest preset temperature. The conventional control module is used to control the air source heat pump water heater to enter the conventional control mode when the power grid's electricity price status is determined to be the conventional electricity price status. In the conventional control mode, the air source heat pump water heater is controlled to operate at the conventional target temperature.

[0016] The negative electricity price control method and device for air source heat pump water heaters provided in this application determine the grid electricity price status signal by combining the duration of the signal, filtering grid signal jitter interference, and avoiding frequent start-stop of the unit; when the negative electricity price trigger state is determined, the auxiliary electric heating module is forcibly turned on and the target temperature of the water tank is set to the highest preset temperature, maximizing the consumption of surplus grid electricity and obtaining subsidy benefits for users; in addition, by combining multi-mode priority setting, signal anomaly handling and safety protection logic, the stable operation of the equipment under complex grid conditions is ensured. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly described below. Obviously, the drawings described below are only for illustrating preferred embodiments and are not intended to limit the scope of this application. In the drawings: Figure 1 This is a flowchart illustrating the negative electricity price control method for air source heat pump water heaters provided in this application embodiment. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0020] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0022] The hardware system of an air source heat pump water heater typically includes components such as a compressor, evaporator, throttling device, and condenser, as well as a heat pump system with an auxiliary electric heating module installed inside the water tank or on the circulation pipeline.

[0023] In one embodiment, this application provides a method for controlling negative electricity prices in an air source heat pump water heater. This method can be executed by a controller (such as a microprocessor or main control chip) built into the air source heat pump water heater to achieve intelligent scheduling of the unit's operating status, such as... Figure 1 As shown, the method specifically includes the following steps: The system collects the electricity price status signal output from the power grid in real time; it determines the current electricity price status of the power grid based on the duration of the electricity price status signal; when the electricity price status of the power grid is determined to be a negative electricity price trigger state, the air source heat pump water heater enters the negative electricity price control mode. In the negative electricity price control mode, the auxiliary electric heating module of the air source heat pump water heater is turned on, and the target temperature of the hot water in the water tank of the air source heat pump water heater is set to the highest preset temperature; when the electricity price status of the power grid is determined to be a normal electricity price state, the air source heat pump water heater enters the normal control mode. In the normal control mode, the air source heat pump water heater is controlled to operate at the normal target temperature.

[0024] In some embodiments, the electricity price status signal is a dry contact switching signal output by the smart grid or electricity meter. Accordingly, the step of real-time acquisition of the electricity price status signal output by the grid side specifically includes: the controller of the air source heat pump water heater uses its built-in signal acquisition circuit, such as an optocoupler isolation sampling circuit, to scan and acquire the closed or open state of the dry contact switching signal in real time at a preset sampling period, such as 100ms or 200ms.

[0025] In some embodiments, the step of determining the state based on the duration of the electricity price status signal includes: when the duration of the collected dry contact switch signal in the closed state reaches a first preset threshold (e.g., set to 10 seconds), the electricity price status of the power grid is determined to be a negative electricity price trigger state; when the duration of the collected dry contact switch signal in the open state reaches a second preset threshold (e.g., set to 10 seconds), the electricity price status of the power grid is determined to be a normal electricity price state. By introducing the duration for anti-jitter determination as described above, millisecond-level or second-level glitches and jitters caused by electromagnetic interference during long-distance transmission of the power grid dry contact signal can be effectively filtered out, avoiding frequent start-ups and shutdowns of the unit caused by directly triggering actions based on signal level, thereby protecting the core components of the equipment.

[0026] In one specific embodiment, when the grid's electricity price is determined to be in a negative price trigger state, the controller forcibly activates the auxiliary electric heating module and controls it to operate synchronously with the air source heat pump water heater's heat pump system. Simultaneously, the target temperature for the hot water in the tank is set to the system's highest preset temperature, for example, 70°C or 75°C based on the tank's pressure capacity and anti-scalding specifications. Through this control, the unit can operate at maximum heating power and maximize the sensible heat storage capacity of the tank by utilizing the highest temperature difference, thereby achieving deep utilization of surplus electricity from the grid and providing users with electricity subsidies. In this embodiment, the auxiliary electric heating module can be an electric heating element or a PTC heater.

[0027] In some embodiments, the step of determining the state based on the duration of the electricity price status signal further includes: within a continuous preset determination duration, which is typically greater than the first and second preset thresholds, for example, 30 seconds or 40 seconds, if the duration of the collected dry contact switch signal in the closed state does not reach the first preset threshold and the duration of the open state does not reach the second preset threshold, then the electricity price status of the power grid is determined to be an abnormal signal state. When the electricity price status of the power grid is determined to be an abnormal signal state, the air source heat pump water heater is controlled to maintain the normal control mode and the fault alarm operation corresponding to the electricity price status signal is disabled. For example, after detecting the abnormal signal state, the control board stops sending alarm drive signals to the buzzer and does not push fault codes to the user's APP. By setting the above-mentioned abnormal determination and silent fault tolerance mechanism, the user's basic hot water needs can be guaranteed under extreme conditions where the power grid signal oscillates continuously at high frequencies, while avoiding false alarms from the equipment or abnormal lock-up shutdown of the unit caused by power grid signal fluctuations.

[0028] In some embodiments, the negative electricity price control method further includes a dynamic switching step of the operating mode: During the operation of the air source heat pump water heater in the negative electricity price control mode, if the duration for which the collected dry contact switch signal is in the open state reaches a second preset threshold, the negative electricity price control mode is exited, the forced-operation auxiliary electric heating module is turned off, the target temperature is adjusted back to the normal set value, and the system switches to the normal control mode; during the operation of the air source heat pump water heater in the normal control mode, if the duration for which the collected dry contact switch signal is in the closed state reaches a first preset threshold, the system seamlessly switches to the negative electricity price control mode. Through this dynamic switching mechanism, the unit can accurately adapt to the real-time changes in the grid electricity price, achieving a smooth transition between surplus power consumption and normal energy-saving operation.

[0029] In some embodiments, the control system of an air source heat pump water heater is pre-configured with a rapid heating control mode and a power limiting control mode, in addition to the conventional control mode.

[0030] Specifically, the power scheduling logic configuration of the rapid heating control mode is as follows: the compressor and auxiliary electric heating module of the heat pump system are started simultaneously, and the compressor is controlled to operate at a preset high frequency state, so that the unit is kept in the maximum heating power output state; during operation, when the real-time water temperature of the water tank is detected to reach the user-set normal target temperature (e.g., 55°C), the unit is controlled to stop heating operation.

[0031] Accordingly, the power scheduling logic of the power limiting control mode is configured as follows: the auxiliary electric heating module is forcibly prohibited from being turned on, and a maximum frequency threshold limit is applied to the operating frequency of the heat pump system compressor to constrain the total input power of the whole machine, thereby maintaining the basic heating demand of the system within the limited power threshold range.

[0032] In this embodiment, the execution priorities of the negative electricity price control mode, the rapid heating control mode, and the power curtailment control mode decrease sequentially. Through this priority setting, when the generating unit receives a power curtailment command and is operating at low power, if the grid triggers a negative electricity price state, the generating unit will ignore the power curtailment command, forcibly release the frequency restriction, and activate the auxiliary electric heating module to help the grid absorb surplus electricity. Similarly, under a negative electricity price state, the rapid heating mode will be overridden by the negative electricity price control mode to ensure that the generating unit can continuously heat the water to the highest preset temperature, preventing the absorption process from being interrupted due to prematurely reaching the rapid heating target temperature, thereby maximizing deep power absorption and user subsidy benefits.

[0033] In some embodiments, under negative electricity price control mode, the negative electricity price control method further includes a low-level protection step: acquiring the real-time water temperature of the air source heat pump water heater, the compressor operating frequency, and operating status parameters (such as exhaust temperature, system high and low pressure, etc.); when the real-time water temperature reaches the highest preset temperature, controlling the auxiliary electric heating module and the heat pump system of the air source heat pump water heater to shut down; when the compressor operating frequency reaches the highest frequency threshold, performing frequency reduction or frequency limiting control operations; when the operating status parameters meet the preset protection trigger conditions, performing the corresponding safety shutdown operation. Through the above protection steps, when the unit is in a high-load operating state under negative electricity price mode, it is possible to effectively prevent water tank overheating and overpressure, compressor overload damage, and other system abnormalities, ensuring the safe and stable operation of the equipment.

[0034] Furthermore, after the auxiliary electric heating module and the heat pump system of the air source heat pump water heater are shut down, the system also includes: when the real-time water temperature is detected to drop to a preset restart temperature threshold, controlling the auxiliary electric heating module and the heat pump system to restart; wherein, the restart temperature threshold is lower than the highest preset temperature, for example, the highest preset temperature is 75℃, and the restart temperature threshold is set to 68℃. Through this restart logic, during the window period before the negative electricity price signal disappears, surplus electricity can be continuously absorbed in a cyclical manner by utilizing the natural heat dissipation of water temperature or the temperature drop caused by user water use.

[0035] In some embodiments, this application also provides a negative electricity price control device for an air source heat pump water heater, which applies a negative electricity price control method for an air source heat pump water heater as described in any of the foregoing embodiments.

[0036] In practical implementation, the negative electricity price control device can be integrated into the main control board or wired controller of the air source heat pump water heater in terms of hardware form. Specifically, it includes: a signal acquisition module for real-time acquisition of the electricity price status signal output from the power grid; a status determination module for determining the current power grid electricity price status based on the duration of the electricity price status signal; a negative electricity price control module for controlling the air source heat pump water heater to enter a negative electricity price control mode when the power grid electricity price status is determined to be a negative electricity price trigger state. In the negative electricity price control mode, the auxiliary electric heating module of the air source heat pump water heater is activated, and the target hot water temperature in the water tank of the air source heat pump water heater is set to the highest preset temperature; and a normal control module for controlling the air source heat pump water heater to enter a normal control mode when the power grid electricity price status is determined to be a normal electricity price state. In the normal control mode, the air source heat pump water heater is controlled to operate at the normal target temperature. The specific working logic and technical effects of the above modules correspond one-to-one with the aforementioned method embodiments and will not be repeated here.

[0037] The negative electricity price control method and device for air source heat pump water heaters provided in this application determine the grid electricity price status signal by combining the duration of the signal, filtering grid signal jitter interference, and avoiding frequent start-ups and shutdowns of the unit; when the negative electricity price trigger state is determined, the auxiliary electric heating module is forcibly turned on and the target temperature of the water tank is set to the highest preset temperature, maximizing the absorption of surplus grid power and obtaining subsidy benefits for users; in addition, by combining multi-mode priority settings, signal anomaly handling, and safety protection logic, the stable operation of the equipment under complex grid conditions is ensured.

[0038] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0039] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is merely a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0040] The steps in the methods of this application embodiment can be adjusted, merged, or deleted according to actual needs. The units in the apparatus of this application embodiment can be merged, divided, or deleted according to actual needs. Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0041] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0042] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for controlling negative electricity prices in an air source heat pump water heater, characterized in that, The method includes the following steps: Real-time acquisition of electricity price status signals output from the power grid side; The current electricity price status of the power grid is determined by judging the status based on the duration of the electricity price status signal. When the power grid's electricity price status is determined to be in a negative electricity price trigger state, the air source heat pump water heater enters the negative electricity price control mode. In the negative electricity price control mode, the auxiliary electric heating module of the air source heat pump water heater is turned on, and the target temperature of the hot water in the water tank of the air source heat pump water heater is set to the highest preset temperature. When the power grid's electricity price is determined to be at a normal electricity price level, the air source heat pump water heater enters a normal control mode, in which the air source heat pump water heater is controlled to operate at a normal target temperature.

2. The negative electricity price control method for an air source heat pump water heater according to claim 1, characterized in that, The electricity price status signal is a dry contact switching signal; The steps for real-time acquisition of the electricity price status signal output from the power grid side include: The closed or open state of the dry contact switch signal is collected in real time at a preset sampling period.

3. The negative electricity price control method for an air source heat pump water heater according to claim 2, characterized in that, The step of determining the state based on the duration of the electricity price status signal includes: When the duration of the collected dry contact switch signal in the closed state reaches a first preset threshold, the electricity price state of the power grid is determined to be the negative electricity price trigger state. When the duration of the collected dry contact switch signal being in the disconnected state reaches the second preset threshold, the electricity price status of the power grid is determined to be the normal electricity price status.

4. The negative electricity price control method for an air source heat pump water heater according to claim 3, characterized in that, The step of determining the state based on the duration of the electricity price status signal further includes: If, within a continuous preset determination period, the duration for which the collected dry contact switch signal is in a closed state does not reach the first preset threshold, and the duration for which it is in an open state does not reach the second preset threshold, then the electricity price status of the power grid is determined to be an abnormal signal status. When the power grid's electricity price status is determined to be in the abnormal signal state, the air source heat pump water heater is controlled to maintain the normal control mode, and the fault alarm operation corresponding to the electricity price status signal is disabled.

5. The negative electricity price control method for an air source heat pump water heater according to claim 3, characterized in that, The negative electricity price control method also includes an operation mode switching step: If, during the operation of the air source heat pump water heater in the negative electricity price control mode, the duration for which the collected dry contact switch signal remains in the open state reaches the second preset threshold, then the negative electricity price control mode will be exited and the system will switch to the normal control mode. If, during the operation of the air source heat pump water heater in the conventional control mode, the duration for which the collected dry contact switch signal remains in a closed state reaches the first preset threshold, then the system switches to the negative electricity price control mode.

6. The negative electricity price control method for an air source heat pump water heater according to claim 1, characterized in that, The air source heat pump water heater is also preset with a rapid heating control mode and a power restriction control mode; the execution priority of the negative electricity price control mode, the rapid heating control mode, and the power restriction control mode decreases in that order.

7. The negative electricity price control method for an air source heat pump water heater according to claim 1, characterized in that, Under the negative electricity price control mode, the negative electricity price control method further includes: The real-time water temperature, compressor operating frequency, and operating status parameters of the air source heat pump water heater are obtained. When the real-time water temperature reaches the maximum preset temperature, the auxiliary electric heating module and the heat pump system of the air source heat pump water heater are controlled to stop. When the compressor operating frequency reaches the highest frequency threshold, frequency reduction or frequency limiting control operation is performed. When the operating status parameters meet the preset protection trigger conditions, the corresponding safety shutdown operation is executed.

8. The negative electricity price control method for an air source heat pump water heater according to claim 7, characterized in that, After the auxiliary electric heating module and the heat pump system of the air source heat pump water heater are shut down, the method further includes: when the real-time water temperature is detected to drop to a preset restart temperature threshold, controlling the auxiliary electric heating module and the heat pump system to restart; wherein the restart temperature threshold is less than the highest preset temperature.

9. The negative electricity price control method for an air source heat pump water heater according to claim 1, characterized in that, The auxiliary electric heating module is an electric heating tube or a PTC heater; under the negative electricity price control mode, the auxiliary electric heating module is controlled to start and run synchronously with the heat pump system of the air source heat pump water heater.

10. A negative electricity price control device for an air source heat pump water heater, characterized in that, The method for controlling negative electricity prices in an air source heat pump water heater as described in any one of claims 1-9, wherein the negative electricity price control device comprises: The signal acquisition module is used to acquire the electricity price status signal output by the power grid side in real time; The status determination module is used to determine the current electricity price status of the power grid based on the duration of the electricity price status signal. The negative electricity price control module is used to control the air source heat pump water heater to enter the negative electricity price control mode when the electricity price status of the power grid is determined to be a negative electricity price trigger state. In the negative electricity price control mode, the auxiliary electric heating module of the air source heat pump water heater is turned on, and the target temperature of the hot water in the water tank of the air source heat pump water heater is set to the highest preset temperature. The conventional control module is used to control the air source heat pump water heater to enter the conventional control mode when the power grid's electricity price status is determined to be the conventional electricity price status. In the conventional control mode, the air source heat pump water heater is controlled to operate at the conventional target temperature.

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