Control method and control apparatus for photovoltaic air conditioning system, and photovoltaic air conditioning system

Abstract

Disclosed in the present invention are a control method and control apparatus for a photovoltaic air conditioning system, and a photovoltaic air conditioning system, which can solve the technical problem of unstable operation of existing photovoltaic air conditioning systems. The control method comprises: when a photovoltaic air conditioning system is in an off-grid state and real-time output power of a photovoltaic module is less than real-time required power of an air conditioning load, executing the following control process: acquiring a difference between the real-time required power of the air conditioning load and the real-time output power of the photovoltaic module as a power deviation; processing the power deviation to obtain a compensation rotational speed; acquiring a difference between a rotational speed setpoint and the compensation rotational speed as a target rotational speed; processing the compensation rotational speed to obtain a rotational speed adjustment step size; acquiring a real-time rotational speed of an air conditioning compressor and comparing the real-time rotational speed with the target rotational speed; and on the basis of the comparison result in combination with the real-time rotational speed, the rotational speed adjustment step size and the target rotational speed, controlling the air conditioning compressor to operate.

Description

Control methods, control devices, and photovoltaic air conditioning systems Technical Field

[0001] This invention belongs to the field of energy-saving air treatment technology, specifically, it relates to a control method, control device, and photovoltaic air conditioning system. Background Technology

[0002] As an energy-saving air conditioning system, photovoltaic air conditioning systems have been widely applied in various fields such as production and daily life due to the increasingly urgent need for energy conservation and emission reduction and the continuous maturation of photovoltaic technology.

[0003] To meet users' air conditioning needs while maximizing the use of solar energy, photovoltaic (PV) air conditioning systems typically operate in a hybrid mode when the grid is supplying power normally, with both the grid and PV modules simultaneously powering the system. When the grid is interrupted, the PV system is in an off-grid state, powered solely by the PV modules. When the power provided by the PV modules is insufficient to meet the system's power requirements, the system often experiences synchronization issues or shutdowns, leading to instability and affecting its usability. Technical issues

[0004] The purpose of this invention is to provide a control method and control device for a photovoltaic air conditioning system, so as to improve the operational stability of the photovoltaic air conditioning system. Technical solutions

[0005] To achieve the above-mentioned objectives, the control method for the photovoltaic air conditioning system provided by this invention adopts the following technical solution:

[0006] A control method for a photovoltaic air conditioning system, comprising:

[0007] Obtain the real-time output power of the photovoltaic modules and the real-time power demand of the air conditioning load in the photovoltaic air conditioning system.

[0008] When the photovoltaic air conditioning system is in an off-grid state and the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load, the following control process is executed:

[0009] The difference between the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic module is obtained as the power deviation;

[0010] The power deviation is processed to obtain the speed for compensation;

[0011] The difference between the given rotational speed and the compensation rotational speed is obtained as the target rotational speed; the compensation rotational speed is processed to obtain the rotational speed adjustment step size;

[0012] Obtain the real-time speed of the air conditioner compressor and compare it with the target speed;

[0013] When the real-time speed is less than or equal to the target speed, the real-time speed is used as the base speed, and the real-time speed is increased by the speed adjustment step to obtain a first actual speed. The air conditioning compressor is controlled to run at the first actual speed until the first actual speed is increased to the target speed.

[0014] When the real-time speed is greater than the target speed, the real-time speed is used as the base speed, and the real-time speed is reduced by the speed adjustment step size to obtain a second actual speed. The air conditioning compressor is controlled to run at the second actual speed until the second actual speed is reduced to the target speed.

[0015] In some embodiments of this application, the power deviation is processed to obtain a compensation rotational speed, specifically including:

[0016] The power deviation is processed by proportional-integral processing to obtain the speed for compensation.

[0017] In some embodiments of this application, the speed for compensation is processed to obtain the speed adjustment step size, specifically including:

[0018] Perform proportional or proportional-integral calculations on the compensation rotation speed to obtain the calculation result;

[0019] The calculation result is subjected to amplitude limiting processing to obtain the speed adjustment step size.

[0020] In some embodiments of this application, the rotational speed is determined using the following process:

[0021] The system acquires the real-time temperature and humidity of the indoor environment where the photovoltaic air conditioning system is located, as well as the real-time fan speed of the indoor unit in the photovoltaic air conditioning system.

[0022] The real-time effective temperature index is determined based on the real-time temperature, the real-time humidity, and the real-time fan speed.

[0023] The difference between the given effective temperature index and the real-time effective temperature index is obtained as the effective temperature index deviation;

[0024] The effective temperature deviation is processed to obtain the given rotational speed.

[0025] In some embodiments of this application, the effective temperature deviation is processed to obtain the given rotational speed, specifically including:

[0026] The effective temperature deviation is processed by proportional-integral processing to obtain the given rotational speed.

[0027] To achieve the aforementioned objectives, the control device for the photovoltaic air conditioning system provided by this invention employs the following technical solution:

[0028] A control device for a photovoltaic air conditioning system, comprising:

[0029] A real-time output power acquisition unit for photovoltaic modules is used to acquire the real-time output power of photovoltaic modules in a photovoltaic air conditioning system.

[0030] The real-time power demand acquisition unit for air conditioning load is used to acquire the real-time power demand of the air conditioning load in the photovoltaic air conditioning system.

[0031] The control unit is configured to execute the following control process when the photovoltaic air conditioning system is in an off-grid state and the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load:

[0032] The difference between the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic module is obtained as the power deviation;

[0033] The power deviation is processed to obtain the speed for compensation;

[0034] The difference between the given rotational speed and the compensation rotational speed is obtained as the target rotational speed; the compensation rotational speed is processed to obtain the rotational speed adjustment step size;

[0035] Obtain the real-time speed of the air conditioner compressor and compare it with the target speed;

[0036] When the real-time speed is less than or equal to the target speed, the real-time speed is used as the base speed, and the real-time speed is increased by the speed adjustment step to obtain a first actual speed. The air conditioning compressor is controlled to run at the first actual speed until the first actual speed is increased to the target speed.

[0037] When the real-time speed is greater than the target speed, the real-time speed is used as the base speed, and the real-time speed is reduced by the speed adjustment step size to obtain a second actual speed. The air conditioning compressor is controlled to run at the second actual speed until the second actual speed is reduced to the target speed.

[0038] Another object of the present invention is to provide a photovoltaic air conditioning system, including a photovoltaic module and an air conditioner, wherein the photovoltaic air conditioning system further includes the control device of the photovoltaic air conditioning system described above.

[0039] Another object of the present invention is to provide a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the control method of the photovoltaic air conditioning system described above is implemented. Beneficial effects

[0040] Compared with the prior art, the advantages and positive effects of the present invention are:

[0041] The photovoltaic air conditioning system and its control method and device provided by this invention, when the photovoltaic air conditioning system is in an off-grid state with grid disconnection, is powered by photovoltaic modules. When the real-time output power of the photovoltaic modules is less than the real-time demand power of the air conditioning load, a compensation speed is determined based on the power deviation between the real-time output power and the real-time demand power. A target speed is determined based on the compensation speed and the given speed. A speed adjustment step size is also obtained based on the compensation speed. Finally, the compressor is controlled based on the speed adjustment step size and the target speed. The target speed is determined based on power supply and demand. Controlling the compressor with this target speed allows the air conditioner to follow changes in power supply and demand, avoiding the air conditioner from losing synchronization or stopping due to supply and demand mismatch, thus improving the operational stability of the air conditioner. Furthermore, since the obtained speed adjustment step size is a non-fixed value, the air conditioning compressor speed is dynamically adjusted by gradually increasing or decreasing based on the non-fixed first speed adjustment step size. This allows the air conditioning compressor speed to adapt to changes in different operating conditions of the photovoltaic air conditioning system, effectively solving the problem of air conditioning instability caused by sudden changes in the demand power of the air conditioning load and / or the output power of the photovoltaic modules, further improving the operational stability of the air conditioner.

[0042] Other features and advantages of the present invention will become clearer after reading the detailed embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0044] Figure 1 is a flowchart of the first embodiment of the control method of the photovoltaic air conditioning system of the present invention;

[0045] Figure 2 is a flowchart of the second embodiment of the control method of the photovoltaic air conditioning system of the present invention;

[0046] Figure 3 is a schematic diagram of the structure of a control device for a photovoltaic air conditioning system according to an embodiment of the present invention. Embodiments of the present invention

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0048] It should be noted that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they can be implemented by those skilled in the art. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0049] Figure 1 shows a flowchart of the first embodiment of the control method for the photovoltaic air conditioning system of the present invention. In this embodiment, the photovoltaic air conditioning system includes photovoltaic modules and an air conditioner, which can be powered by the power grid and / or the photovoltaic modules. The control method of this embodiment includes:

[0050] S11: Determine the conditions that the photovoltaic air conditioning system is in an off-grid state and the real-time output power of the photovoltaic modules is less than the real-time demand power of the air conditioning load.

[0051] In this embodiment, it is necessary to obtain the real-time output power of the photovoltaic modules in the photovoltaic air conditioning system and the real-time demand power of the air conditioning load.

[0052] The real-time output power of the photovoltaic (PV) module is the output power of the PV module acquired in real time according to a set sampling period. The real-time power demand of the air conditioning load is the power demand of the air conditioning load acquired in real time according to a set sampling period. The real-time output power of the PV module can be acquired using related technologies, and this embodiment does not limit the specific acquisition method. In some embodiments, the real-time output power of the PV module is acquired based on the real-time output voltage and real-time output current of the PV module. In other embodiments, the real-time output power of the PV module is acquired based on predictions from a PV module power generation prediction model. The real-time power demand of the air conditioning load can be acquired using related technologies, and this embodiment does not limit the specific acquisition method. In some embodiments, the real-time power demand of the air conditioning load is acquired based on predictions from an air conditioning load prediction model. In other embodiments, the real-time power demand of the air conditioning load is calculated based on the real-time temperature and set temperature of the indoor environment where the air conditioner is located.

[0053] In this embodiment, the grid status is also monitored in real time, and when the grid is interrupted, it is determined that the photovoltaic air conditioning system is in an off-grid state. In the off-grid state, the photovoltaic modules will supply power to the photovoltaic air conditioning system independently. Furthermore, in the off-grid state, the real-time output power of the photovoltaic modules is compared with the real-time power demand of the air conditioning load to determine whether the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load.

[0054] If the real-time output power of the photovoltaic module is less than the real-time power demand of the air conditioning load, it indicates that the power provided by the photovoltaic module cannot meet the power requirements of the air conditioning system. To ensure the use of the air conditioning, it is necessary to control the air conditioning to reduce its actual operating power. Moreover, to ensure the stability of the air conditioning during reduced power operation, this embodiment uses the control process described in steps S12 to S16 to control the air conditioning.

[0055] S12: Obtain the difference between the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic module as the power deviation.

[0056] S13: Process the power deviation to obtain the speed for compensation.

[0057] The compensation speed is determined based on the power deviation and changes with the power deviation. This embodiment does not limit the specific method for determining the compensation speed.

[0058] In some embodiments, the power deviation is subjected to proportional-integral processing to obtain the speed for compensation.

[0059] S14: Obtain the difference between the given speed and the compensation speed as the target speed; process the compensation speed to obtain the speed adjustment step size.

[0060] The given rotational speed is known and obtainable. In some embodiments, the given rotational speed is a set value, which is a fixed value. In other embodiments, the given rotational speed may also be a variable value. This embodiment does not limit the specific method of determining the given rotational speed. Then, the difference between the given rotational speed and the compensation rotational speed is calculated, and this difference is determined as the target rotational speed.

[0061] The speed adjustment step size changes with the speed of compensation, and this embodiment does not limit the specific determination method.

[0062] In some embodiments, a proportional or proportional-integral operation is performed on the compensation speed to obtain the calculation result; then, the calculation result is limited to obtain the compensation speed. Limiting the calculation result includes limiting the maximum value and the minimum value of the result. Obtaining the compensation speed by limiting the calculation result avoids the compensation speed being too high or too low, which could affect the operational stability of subsequent air conditioning control.

[0063] S15: Obtain the real-time speed of the air conditioner compressor and compare it with the target speed.

[0064] The real-time speed of the air conditioner compressor is the speed of the air conditioner compressor obtained in real time according to the set sampling period.

[0065] S16: Based on the comparison results, combined with the real-time speed, speed adjustment step size and target speed, control the operation of the air conditioning compressor.

[0066] Specifically, when the real-time speed is less than or equal to the target speed, the compressor speed is increased. Furthermore, when increasing the speed, the real-time speed is used as the base speed, and a speed adjustment step size is applied to increase the real-time speed to obtain a first actual speed. The air conditioning compressor is then controlled to operate at this first actual speed until it reaches the target speed, at which point speed adjustment stops. It should be understood that the first actual speed obtained by increasing the speed adjustment step size from the current real-time speed will be used as the real-time speed for the next speed adjustment. The next first actual speed will then be obtained by further increasing the speed adjustment step size from this base speed. For example, the first real-time speed might be denoted as N. up The speed adjustment step size is denoted as N. a The first actual rotational speed is denoted as N. n1 Then we have: N n1 = N up +k×N a k is a natural number, representing the number of adjustments.

[0067] If the real-time speed is greater than the target speed, the compressor speed is reduced. Furthermore, during speed reduction, the real-time speed is used as the base speed, and a speed adjustment step size is used to reduce the real-time speed to obtain a second actual speed. This second actual speed is then used to control the air conditioning compressor until it reaches the target speed. Similarly, the second actual speed obtained by reducing the speed adjustment step size from the current real-time speed will be used as the real-time speed for the next speed adjustment. The speed adjustment step size is then further reduced from this second actual speed to obtain the next second actual speed. For example, let the first real-time speed be denoted as N. down The speed adjustment step size is still recorded as N. a The second actual rotational speed is denoted as N. n2 Then we have: N n2 = N down -m×N a , where m is a natural number and represents the number of adjustments.

[0068] In the above embodiments, when the photovoltaic air conditioning system is in an off-grid state due to a power outage, the system is powered by photovoltaic modules. When the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load, a compensation speed is determined based on the power deviation between the real-time output power and the real-time power demand. A target speed is determined based on the compensation speed and the given speed. A speed adjustment step size is also obtained based on the compensation speed. Finally, the compressor is controlled based on the speed adjustment step size and the target speed. On one hand, the target speed is determined based on power supply and demand. Controlling the compressor at this target speed allows the air conditioning to follow changes in power supply and demand, avoiding malfunctions or shutdowns due to supply-demand mismatch, thus improving the stability of the air conditioning operation. On the other hand, the speed adjustment step size is dynamically determined based on the compensation speed, which in turn is dynamically determined based on the power deviation. The power deviation is dynamically determined based on the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic modules. Since the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic modules are usually non-fixed values, the final determined speed adjustment step size is also non-fixed. Furthermore, based on a non-fixed speed adjustment step size, the speed of the air conditioner compressor is dynamically adjusted, gradually increasing or decreasing, so that the speed of the air conditioner compressor can adapt to the changes in different operating conditions of the photovoltaic air conditioning system, effectively solving the problem of unstable air conditioning operation caused by sudden changes in the demand power of the air conditioning load and / or the output power of the photovoltaic modules.

[0069] Figure 2 shows a flowchart of a second embodiment of the control method for the photovoltaic air conditioning system of the present invention. In this embodiment, the photovoltaic air conditioning system includes photovoltaic modules and an air conditioner, which can be powered by the power grid and / or the photovoltaic modules. When the photovoltaic air conditioning system is in an off-grid state, and the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load, the air conditioner is controlled using the control method of the above embodiment. Moreover, during the control process, the speed setpoint used to determine the target speed is a variable value, and it is a dynamically variable value that follows the temperature, humidity, and the speed of the indoor unit fan of the air conditioner.

[0070] Specifically, the rotational speed is determined using the following process.

[0071] S21: Obtain the real-time temperature and humidity of the indoor environment where the photovoltaic air conditioning system is located, as well as the real-time fan speed of the indoor unit in the photovoltaic air conditioning system.

[0072] S22: Determine the real-time effective temperature index based on real-time temperature, real-time humidity, and real-time fan speed. The specific determination method is not limited and can be implemented using relevant technologies.

[0073] S23: Obtain the difference between the given effective temperature index and the real-time effective temperature index as the effective temperature index deviation. The given effective temperature index is known.

[0074] S24: Process the effective temperature deviation to obtain the speed command.

[0075] The rotational speed setting varies with the effective temperature deviation, and this embodiment does not limit the specific determination method.

[0076] In some embodiments, the rotational speed is obtained by performing proportional-integral processing on the effective temperature deviation.

[0077] By determining the real-time effective temperature index based on real-time temperature, real-time humidity, and real-time fan speed, and then determining the speed setpoint based on the real-time effective temperature index, the speed setpoint is matched with the real-time indoor environment. The target speed of the compressor is then determined based on the speed setpoint, and the compressor is controlled to run at the target speed. This adapts to the real-time indoor environment and improves the comfort of the air conditioner's indoor environment regulation.

[0078] Figure 3 shows a schematic diagram of a control device for a photovoltaic air conditioning system according to an embodiment of the present invention. In this embodiment, the photovoltaic air conditioning system includes photovoltaic modules and an air conditioner, which can be powered by the power grid and / or the photovoltaic modules. The structural units included in the control device of this embodiment, the functions of the structural units, and the relationships between them are as follows:

[0079] The control device includes:

[0080] The real-time output power acquisition unit 31 of the photovoltaic module is used to acquire the real-time output power of the photovoltaic module in the photovoltaic air conditioning system.

[0081] The real-time power demand acquisition unit 32 for air conditioning load is used to acquire the real-time power demand of the air conditioning load in the photovoltaic air conditioning system.

[0082] The control unit 33 is configured to execute the following control process when the photovoltaic air conditioning system is in an off-grid state and the real-time output power of the photovoltaic modules obtained by the real-time output power acquisition unit 31 is less than the real-time demand power of the air conditioning load obtained by the real-time demand power acquisition unit 32:

[0083] The difference between the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic modules is obtained as the power deviation.

[0084] The power deviation is processed to obtain the speed for compensation;

[0085] Obtain the difference between the given speed and the compensation speed as the target speed; process the compensation speed to obtain the speed adjustment step size;

[0086] Obtain the real-time speed of the air conditioner compressor and compare it with the target speed;

[0087] When the real-time speed is less than or equal to the target speed, the real-time speed is used as the base speed, and the real-time speed is increased by the speed adjustment step to obtain the first actual speed. The air conditioning compressor is controlled to run at the first actual speed until the first actual speed is increased to the target speed.

[0088] When the real-time speed is greater than the target speed, the real-time speed is used as the base speed, and the real-time speed is reduced by adjusting the speed step size to obtain the second actual speed. The operation of the air conditioning compressor is controlled by the second actual speed until the second actual speed is reduced to the target speed.

[0089] The control device described above runs the corresponding software program, performs the corresponding functions, and controls the photovoltaic air conditioning system according to the control method embodiment of Figure 1 and other embodiments, so as to achieve the corresponding technical effects as the embodiment of Figure 1 and other embodiments.

[0090] The control device described in the above embodiments is applied to a photovoltaic air conditioning system, which can improve the continuous operational stability of the photovoltaic air conditioning system and ensure the use of the air conditioning system.

[0091] Other embodiments of the present invention also provide a computer storage medium storing a computer program. When the computer program is executed by a processor, it implements the control method of the photovoltaic air conditioning system of the embodiment of FIG1, the embodiment of FIG2, or other embodiments, and achieves the technical effects of the corresponding embodiments.

[0092] The aforementioned computer storage media can be implemented using any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The computer storage media can be any available storage medium accessible to general-purpose or special-purpose computers.

[0093] In some embodiments, a computer storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Alternatively, the storage medium can be an integral part of the processor. Both the processor and the storage medium can reside in application-specific integrated circuits (ASICs). Of course, the processor and storage medium can also exist as discrete components in the device.

[0094] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by the present invention.

Claims

1. A control method for a photovoltaic air conditioning system, characterized in that, The control method includes: Obtain the real-time output power of the photovoltaic modules and the real-time power demand of the air conditioning load in the photovoltaic air conditioning system. When the photovoltaic air conditioning system is in an off-grid state and the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load, the following control process is executed: The difference between the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic module is obtained as the power deviation; The power deviation is processed to obtain the speed for compensation; The difference between the given rotational speed and the compensation rotational speed is obtained as the target rotational speed; the compensation rotational speed is processed to obtain the rotational speed adjustment step size; Obtain the real-time speed of the air conditioner compressor and compare it with the target speed; When the real-time speed is less than or equal to the target speed, the real-time speed is used as the base speed, and the real-time speed is increased by the speed adjustment step to obtain a first actual speed. The air conditioning compressor is controlled to run at the first actual speed until the first actual speed is increased to the target speed. When the real-time speed is greater than the target speed, the real-time speed is used as the base speed, and the real-time speed is reduced by the speed adjustment step size to obtain a second actual speed. The air conditioning compressor is controlled to run at the second actual speed until the second actual speed is reduced to the target speed.

2. The control method for a photovoltaic air conditioning system according to claim 1, characterized in that, The power deviation is processed to obtain the compensation speed, specifically including: The power deviation is processed by proportional-integral processing to obtain the speed for compensation.

3. The control method for the photovoltaic air conditioning system according to claim 1, characterized in that, The speed for compensation is processed to obtain the speed adjustment step size, specifically including: Perform proportional or proportional-integral calculations on the compensation rotation speed to obtain the calculation result; The calculation result is subjected to amplitude limiting processing to obtain the speed adjustment step size.

4. The control method for the photovoltaic air conditioning system according to any one of claims 1 to 3, characterized in that, The given rotational speed is determined using the following process: The system acquires the real-time temperature and humidity of the indoor environment where the photovoltaic air conditioning system is located, as well as the real-time fan speed of the indoor unit in the photovoltaic air conditioning system. The real-time effective temperature index is determined based on the real-time temperature, the real-time humidity, and the real-time fan speed. The difference between the given effective temperature index and the real-time effective temperature index is obtained as the effective temperature index deviation; The effective temperature deviation is processed to obtain the given rotational speed.

5. The control method for the photovoltaic air conditioning system according to claim 4, characterized in that, The effective temperature deviation is processed to obtain the given rotational speed, specifically including: The effective temperature deviation is processed by proportional-integral processing to obtain the given rotational speed.

6. A control device for a photovoltaic air conditioning system, characterized in that, The control device includes: A real-time output power acquisition unit for photovoltaic modules is used to acquire the real-time output power of photovoltaic modules in a photovoltaic air conditioning system. The real-time power demand acquisition unit for air conditioning load is used to acquire the real-time power demand of the air conditioning load in the photovoltaic air conditioning system. The control unit is configured to execute the following control process when the photovoltaic air conditioning system is in an off-grid state and the real-time output power of the photovoltaic modules is less than the real-time power demand of the air conditioning load: The difference between the real-time power demand of the air conditioning load and the real-time output power of the photovoltaic module is obtained as the power deviation; The power deviation is processed to obtain the speed for compensation; The difference between the given rotational speed and the compensation rotational speed is obtained as the target rotational speed; the compensation rotational speed is processed to obtain the rotational speed adjustment step size; Obtain the real-time speed of the air conditioner compressor and compare it with the target speed; When the real-time speed is less than or equal to the target speed, the real-time speed is used as the base speed, and the real-time speed is increased by the speed adjustment step to obtain a first actual speed. The air conditioning compressor is controlled to run at the first actual speed until the first actual speed is increased to the target speed. When the real-time speed is greater than the target speed, the real-time speed is used as the base speed, and the real-time speed is reduced by the speed adjustment step size to obtain a second actual speed. The air conditioning compressor is controlled to run at the second actual speed until the second actual speed is reduced to the target speed.

7. The control device for the photovoltaic air conditioning system according to claim 6, characterized in that, The control unit processes the compensation speed to obtain the speed adjustment step size, specifically including: Perform proportional or proportional-integral calculations on the compensation rotation speed to obtain the calculation result; The calculation result is subjected to amplitude limiting processing to obtain the speed adjustment step size.

8. The control device for the photovoltaic air conditioning system according to claim 6 or 7, characterized in that, The given rotational speed is determined using the following process: The system acquires the real-time temperature and humidity of the indoor environment where the photovoltaic air conditioning system is located, as well as the real-time fan speed of the indoor unit in the photovoltaic air conditioning system. The real-time effective temperature index is determined based on the real-time temperature, the real-time humidity, and the real-time fan speed. The difference between the given effective temperature index and the real-time effective temperature index is obtained as the effective temperature index deviation; The effective temperature deviation is processed to obtain the given rotational speed.

9. A photovoltaic air conditioning system, comprising photovoltaic modules and an air conditioner, characterized in that, The photovoltaic air conditioning system further includes the control device for the photovoltaic air conditioning system as described in any one of claims 6 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the control method of the photovoltaic air conditioning system according to any one of claims 1 to 5.

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