Charging and discharging circuit and control method of charging and discharging circuit

Abstract

The invention provides a charging and discharging circuit and a control method of the charging and discharging circuit, the charging and discharging circuit is applied to a photovoltaic energy storage system, the photovoltaic energy storage system comprises a first photovoltaic module, a second photovoltaic module, an energy storage battery and electrical equipment, and the charging and discharging circuit comprises a first boosting unit, a second boosting unit and a buck-boost unit, the output end of the first boosting unit is electrically connected with the output end of the buck-boost unit, the output end of the second boosting unit is electrically connected with the output end of the buck-boost unit, the first boosting unit is used for boosting an output signal of the first photovoltaic module, and the first boosting unit is located in the electrical equipment; the second boosting unit is used for boosting the output signal of the second photovoltaic module, the buck-boost unit is used for boosting or reducing the output signal of the energy storage battery, and the problem that the energy utilization rate of an optical storage system in the prior art is low is solved.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a charging and discharging circuit and a control method for the charging and discharging circuit. Background Art

[0002] Photovoltaic energy storage inverter, also known as energy storage cabinet, DCDC energy storage inverter equipment, DCDC inverter equipment in the industry. Its function is to store the DC power of photovoltaic into the battery, and to output the electric energy in the battery to power the DC load.

[0003] The essential purpose of the photovoltaic energy storage inverter is to convert one DC voltage into another DC voltage, while controlling the input and output current and power. At present, photovoltaic energy storage inverters are two-way bidirectional circuits, which are used to realize the function of both charging the battery and discharging the battery for air conditioning operation. Due to the uncertainty of sunlight, it is inevitable that the power generation of photovoltaic panels will fluctuate. When the photovoltaic power is insufficient, the two-way bidirectional photovoltaic energy storage inverter cannot charge the battery. When the photovoltaic power is too sufficient, the excess photovoltaic power cannot be used, resulting in energy waste. Therefore, a three-way photovoltaic energy storage inverter charging and discharging circuit is adopted to optimize the utilization of photovoltaic energy. Summary of the invention

[0004] The main purpose of the present application is to provide a charging and discharging circuit and a control method for the charging and discharging circuit, so as to at least solve the problem of low energy utilization rate of the photovoltaic storage system in the prior art.

[0005] According to one aspect of the present application, a charge and discharge circuit is provided, which is applied to a photovoltaic energy storage system, wherein the photovoltaic energy storage system includes a first photovoltaic component, a second photovoltaic component, an energy storage battery and an electrical device, and the charge and discharge circuit includes a first boost unit, a second boost unit and a buck-boost unit, wherein the output end of the first boost unit is electrically connected to the output end of the buck-boost unit, the output end of the second boost unit is electrically connected to the output end of the buck-boost unit, the first boost unit is used to boost the output signal of the first photovoltaic component, and the first boost unit is located in the electrical device, the second boost unit is used to boost the output signal of the second photovoltaic component, and the buck-boost unit is used to boost or buck the output signal of the energy storage battery.

[0006] Optionally, the first boost unit includes a first impedance, a first switching device, a second switching device, a third switching device and a second impedance, wherein the first end of the first impedance is electrically connected to the second end of the first switching device, the first end of the first switching device, the first end of the second switching device and the first end of the third switching device are electrically connected, the second end of the third switching device is electrically connected to the first end of the second impedance, the second end of the first impedance and the second end of the second impedance are input ends of the first boost unit, and the second end of the second switch device is the output end of the first boost unit.

[0007] Optionally, the second boost unit includes a third impedance, a fourth switching device, a fifth switching device, a sixth switching device, a fourth impedance and a fifth impedance, wherein the second end of the third impedance is electrically connected to the first end of the fourth switching device, the second end of the fourth switching device, the first end of the fifth switching device and the first end of the sixth switching device are electrically connected, the second end of the sixth switching device is electrically connected to the first end of the fifth impedance, the second end of the fifth switching device is electrically connected to the first end of the fourth impedance, the second end of the fourth impedance is the output end of the second boost unit, and the first end of the third impedance and the second end of the fifth impedance are the input ends of the second boost unit.

[0008] Optionally, the buck-boost unit includes a sixth impedance, a seventh impedance, a seventh switch device, an eighth switch device, an eighth impedance, a ninth switch device, a ninth impedance, a tenth switch device and an eleventh switch device, wherein the first end of the tenth switch device, the first end of the eleventh switch device, the first end of the sixth impedance and the first end of the seventh impedance are electrically connected, the second end of the tenth switch device and the second end of the sixth impedance are input ends of the buck-boost unit, the second end of the seventh impedance, the first end of the seventh switch device and the first end of the eighth switch device are electrically connected, the second end of the eighth switch device is electrically connected to the first end of the eighth impedance, the second end of the seventh switch device is electrically connected to the first end of the ninth switch device, the second end of the ninth switch device is electrically connected to the first end of the ninth impedance, and the second end of the ninth impedance is electrically connected to the second end of the eighth impedance.

[0009] According to another aspect of the present application, a control method for the charging and discharging circuit described in any one of the above is provided, including: obtaining the input power of the first photovoltaic component to obtain the first power, and obtaining the input power of the second photovoltaic component to obtain the second power; obtaining the remaining power of the energy storage battery, and determining whether to control the electrical equipment to work, and in the case of controlling the electrical equipment to work, determining whether the sum of the first power and the second power is greater than the rated power of the electrical equipment; in the case where the sum of the first power and the second power is greater than the rated power of the electrical equipment, controlling the first boost unit, the second boost unit and the buck-boost unit to work according to the relationship between the remaining power and the maximum value of the remaining power; in the case where the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, controlling at least two of the first boost unit, the second boost unit and the buck-boost unit to work according to the relationship between the remaining power and the minimum value of the remaining power.

[0010] Optionally, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device and an eleventh switch device. When the sum of the first power and the second power is greater than the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the maximum value of the remaining power, including: when the remaining power is less than the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device and the tenth switch device are controlled to operate; when the remaining power is greater than or equal to the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device and the eleventh switch device are controlled to operate.

[0011] Optionally, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes an eighth switch device and a tenth switch device. When the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, the first boost unit, the second boost unit, and at least two of the buck-boost units are controlled to operate according to the relationship between the remaining power and the minimum value of the remaining power, including: when the remaining power is greater than the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the eighth switch device, and the tenth switch device are controlled to operate; when the remaining power is less than or equal to the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, and the sixth switch device are controlled to operate.

[0012] Optionally, the photovoltaic energy storage system also includes electrical equipment. After determining whether to control the electrical equipment to operate, the method also includes: when the electrical equipment is controlled not to operate, determining whether the sum of the first power and the second power is greater than the rated power of the electrical equipment; when the sum of the first power and the second power is greater than the rated power of the electrical equipment, controlling the first boost unit, the second boost unit and the buck-boost unit to operate according to the relationship between the remaining power and the maximum value of the remaining power; when the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, controlling the first boost unit, the second boost unit and the buck-boost unit to operate according to the relationship between the remaining power and the minimum value of the remaining power.

[0013] Optionally, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device and an eleventh switch device. When the sum of the first power and the second power is greater than the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the maximum value of the remaining power, including: when the remaining power is less than the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device, the tenth switch device and the eleventh switch device are controlled to operate; when the remaining power is greater than or equal to the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device and the eleventh switch device are controlled to operate.

[0014] Optionally, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device and an eleventh switch device. When the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the minimum value of the remaining power, including: when the remaining power is greater than the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device, the tenth switch device and the eleventh switch device are controlled to operate; when the remaining power is less than or equal to the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device and the ninth switch device are controlled to operate.

[0015] By applying the technical solution of the present application, the air conditioner can be powered by the buck-boost unit to the busbar, or the pure energy storage battery can be charged through the buck-boost unit; the energy storage battery can be powered by the air conditioner through the buck-boost unit to the busbar; in addition, the second group of photovoltaic modules can be powered by the air conditioner through the second boost unit to the busbar; compared with the two-way charging and discharging circuit of only one photovoltaic module in the prior art, the present application can optimize the power supply mode and improve the charging efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 A topological structure block diagram of a charging and discharging circuit provided in an embodiment of the present application is shown;

[0018] Figure 2 A schematic diagram of a photovoltaic energy storage air conditioning system according to an embodiment of the present application is shown;

[0019] Figure 3 A flow chart showing a method for controlling a charge and discharge circuit according to an embodiment of the present application is shown;

[0020] Figure 4 A flow chart of a method for controlling a charging and discharging circuit when an air conditioner is turned on according to an embodiment of the present application is shown.

[0021] The above drawings include the following reference numerals:

[0022] 102, a first boost unit; 104, a second boost unit; 106, a buck-boost unit; 108, a first photovoltaic module; 110, a second photovoltaic module; 112, a storage battery; 114, an electrical device; L2, a first impedance; K2, a first switch device; D2, a second switch device; V4, a third switch device; RS2, a second impedance; L3, a third impedance; D3, a fourth switch device; K3, a fifth switch device; V3, a sixth switch device; C3, a fourth impedance; RS3, a fifth impedance; C1, a sixth impedance; L1, a seventh impedance; D1, a seventh switch device; V1, an eighth switch device; RS1, an eighth impedance; V2, a ninth switch device; C2, a ninth impedance; K1, a tenth switch device; K4, an eleventh switch device. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0025] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0026] As introduced in the background technology, the energy utilization rate of the photovoltaic storage system in the prior art is relatively low. To solve the above problem, the embodiments of the present application provide a charging and discharging circuit and a control method for the charging and discharging circuit.

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0028] According to one aspect of the present application, Figure 1 As shown, a charge and discharge circuit is provided, which is applied to a photovoltaic energy storage system. The photovoltaic energy storage system includes a first photovoltaic component 108, a second photovoltaic component 110, an energy storage battery 112 and an electrical device 114. The charge and discharge circuit includes a first boost unit 102, a second boost unit 104 and a buck-boost unit 106, wherein the output end of the first boost unit 102 is electrically connected to the output end of the buck-boost unit 106, the output end of the second boost unit 104 is electrically connected to the output end of the buck-boost unit 106, the first boost unit 102 is used to boost the output signal of the first photovoltaic component 108, and the first boost unit 102 is located in the electrical device 114, the second boost unit 104 is used to boost the output signal of the second photovoltaic component 110, and the buck-boost unit 106 is used to boost or buck the output signal of the energy storage battery 112.

[0029] Specifically, the input voltage of the first group of photovoltaic panels is transmitted through a BUCK-BOOST buck-boost circuit (i.e., buck-boost unit 106) to the bus to supply power to the air conditioner, and then through a BUCK-BOOST buck-boost circuit to charge the battery. The battery is transmitted through a BUCK-BOOST buck-boost circuit to the bus to supply power to the air conditioner. The voltage between the bus voltage and the energy storage battery can be adjusted to achieve a two-way flow of energy, thereby increasing the photovoltaic input voltage to a voltage level suitable for energy storage and inversion. The second group of photovoltaic panels is transmitted through another BOOST boost circuit (i.e., the first boost unit 102) to the bus to supply power to the air conditioner, thereby providing a suitable voltage for loads such as the air conditioner.

[0030] As can be seen from the above, in the embodiment of the present application, the direct current generated by three photovoltaics is introduced into the inverter to provide energy for subsequent conversion and processing, so that the system can use solar energy for power generation and energy storage. By controlling the on and off of the switching device, the inductor stores and releases energy, and the boost function is realized by superimposing it with the power supply voltage. Through the bidirectional Buck-Boost buck-boost circuit, the battery charge and discharge current and voltage are adjusted according to the battery status and system requirements, and the charge and discharge process of the energy storage battery can be flexibly controlled, thereby enhancing the scalability and adaptability of the system and improving the overall performance and reliability of the system.

[0031] Specifically, the 310V energy storage battery can be a lead-acid battery or a lithium battery, which can store electrical energy. It can store electrical energy when there is excess photovoltaic input energy, and release electrical energy when photovoltaic input is insufficient or the load demand is large. It can balance the intermittent nature of photovoltaic power generation and the volatility of load demand, and achieve time shifting of electrical energy and optimal energy allocation. For example, when the light is strong during the day, the excess photovoltaic power is stored in the battery. When the light is insufficient at night or on rainy days, the energy storage battery provides electrical energy to the load, ensuring continuous power supply to the load, improving energy self-sufficiency and power supply reliability, and also helps to smooth the output power of the photovoltaic system, reduce the impact on the power grid, and improve the stability of the power grid.

[0032] The input part of the circuit includes a first group of photovoltaic inputs (165V-350V), a second group of photovoltaic inputs (165V-350V) and a bus voltage (410V). The first group of photovoltaic inputs is connected to the second boost unit 104 through the K3 switch, and the second group of photovoltaic inputs is connected to the second boost unit 104 through the K4 switch. The bus voltage is the input of the energy storage battery.

[0033] In the specific implementation process, Figure 2 As shown, the first boost unit 102 includes a first impedance L2, a first switch device K2, a second switch device D2, a third switch device V4 and a second impedance RS2, wherein the first end of the first impedance L2 is electrically connected to the second end of the first switch device K2, the first end of the first switch device K2, the first end of the second switch device D2 and the first end of the third switch device V4 are electrically connected, the second end of the third switch device V4 is electrically connected to the first end of the second impedance RS2, the second end of the first impedance L2 and the second end of the second impedance RS2 are input ends of the first boost unit 102, and the second end of the second switch device D2 is an output end of the first boost unit 102. The connection relationship of the remaining first photovoltaic assembly 108, the second photovoltaic assembly 110, the energy storage battery 112 and the electrical equipment 114 is the same as Figure 1 The same as in, no further description is given here.

[0034] Specifically, the first impedance L2 is an energy storage inductor, which is usually made of a wire wound on a magnetic core. It can store energy in the first boost unit 102 to achieve a voltage increase. When the switch is closed, the inductor stores energy, the current rises linearly, and a reverse electromotive force is generated at both ends of the inductor to prevent the rapid change of the current. When the switch is disconnected, the inductor releases energy and superimposes it with the power supply voltage to increase the output voltage, thereby achieving the goal of boosting the lower voltage of the photovoltaic input to a higher DC bus voltage or a voltage level suitable for charging the energy storage battery; the first switching device K2 is a mechanical switch or an electronic switch, which can be a relay or a MOS tube, and can control the on and off between the bus voltage and the first boost unit 102.

[0035] Specifically, the second switch device D2 is a diode, which can be an ordinary rectifier diode or a Schottky diode, which plays a unidirectional conductive role to prevent the current from flowing in the opposite direction; the third switch device V4 is a voltage sensor or a voltage-dividing resistor, which can control the inverter DC / AC, monitor the voltage values ​​of each key node in the circuit in real time, and convert it into an electrical signal that can be recognized by the control circuit. When the photovoltaic input voltage is too high or too low, the control circuit can adjust the working state of the first boost unit 102 accordingly to ensure that the output voltage is stable within an appropriate range; when the energy storage battery voltage reaches the full or discharged threshold, the control circuit can stop the charging or discharging process in time to protect the life of the energy storage battery; the second impedance RS2 is a current sensor or a sampling resistor, which measures the current in the circuit and converts the current signal into a voltage signal or a digital signal to feed back to the control circuit. Based on the current detection feedback, the control circuit can grasp the current situation in the circuit in real time to achieve the functions of overcurrent protection and constant current control.

[0036] In the specific implementation process, Figure 2 As shown, the second boost unit 104 includes a third impedance L3, a fourth switch device D3, a fifth switch device K3, a sixth switch device V3, a fourth impedance C3 and a fifth impedance RS3, wherein the second end of the third impedance L3 is electrically connected to the first end of the fourth switch device D3, the second end of the fourth switch device D3, the first end of the fifth switch device K3 and the first end of the sixth switch device V3 are electrically connected, the second end of the sixth switch device V3 is electrically connected to the first end of the fifth impedance RS3, the second end of the fifth switch device K3 is electrically connected to the first end of the fourth impedance C3, the second end of the fourth impedance C3 is the output end of the second boost unit 104, and the first end of the third impedance L3 and the second end of the fifth impedance RS3 are the input ends of the second boost unit 104.

[0037] Specifically, the third impedance L3 is an energy storage inductor, which is usually made of a wire wound on a magnetic core, and can store and release energy to achieve voltage rise and fall; the fourth switch device D3 is a diode. When the inductor releases energy, the diode provides a freewheeling channel for the current, ensuring that the energy in the inductor can be smoothly transferred to the output end without causing current interruption and excessive reverse electromotive force generated by the inductor due to the disconnection of the switch, thereby protecting the circuit components from damage and ensuring that the energy is transmitted in the designed direction to achieve a stable voltage increase; the fifth switch device K3 is a diode, which controls the two groups of photovoltaic inputs and the second boost The sixth switch device V3 is a voltage sensor or a voltage-dividing resistor. Through voltage detection feedback, the control circuit can understand the working state of the circuit, and adjust the switch on-off time, duty cycle and other parameters according to the preset voltage threshold and control strategy to ensure the stable operation of the circuit; the fourth impedance C3 is a capacitor, which can be an electrolytic capacitor or a ceramic capacitor, which can filter and smooth the voltage and store a certain amount of electrical energy; the fifth impedance RS3 is a current sensor or a sampling resistor, which can measure the current in the circuit and convert the current signal into a voltage signal or a digital signal to feed back to the control circuit.

[0038] In the specific implementation process, Figure 2 As shown, the buck-boost unit 106 includes a sixth impedance C1, a seventh impedance L1, a seventh switch device D1, an eighth switch device V1, an eighth impedance RS1, a ninth switch device V2, a ninth impedance C2, a tenth switch device K1 and an eleventh switch device K4, wherein a first end of the tenth switch device K1, a first end of the eleventh switch device K4, a first end of the sixth impedance C1 and a first end of the seventh impedance L1 are electrically connected, a second end of the tenth switch device K1 and a second end of the sixth impedance C1 are input ends of the buck-boost unit 106, a second end of the seventh impedance L1, a first end of the seventh switch device D1 and a first end of the eighth switch device V1 are electrically connected, a second end of the eighth switch device V1 is electrically connected to a first end of the eighth impedance RS1, a second end of the seventh switch device D1 is electrically connected to a first end of the ninth switch device V2, a second end of the ninth switch device V2 is electrically connected to a first end of the ninth impedance C2, and a second end of the ninth impedance C2 is electrically connected to a second end of the eighth impedance RS1.

[0039] Specifically, the sixth impedance C1 and the ninth impedance C2 are electrolytic capacitors or ceramic capacitors, which can filter out high-frequency ripples in the voltage at the output end of the second boost unit 104 and the boost-buck unit 106, making the output voltage more stable and smooth, providing high-quality DC voltage for subsequent circuits or loads, and can also provide a certain current instantly to meet the dynamic requirements of the load and improve the stability and reliability of the circuit. For example, when the load changes suddenly, the capacitor can release or absorb electrical energy to maintain the relative stability of the voltage and prevent large voltage fluctuations, thereby protecting other components in the circuit from voltage shocks.

[0040] Specifically, the seventh impedance L1 is an energy storage inductor, which is usually made of a wire wound around a magnetic core. It plays the role of energy storage and transfer. By controlling the on and off time of the switch, voltage regulation and bidirectional energy flow between the bus voltage and the energy storage battery are achieved, ensuring that the energy storage battery can be charged and discharged at a suitable voltage, thereby improving energy utilization efficiency; the seventh switch device D1 is an ordinary rectifier diode or Schottky diode. When the inductor releases energy, the diode provides a freewheeling channel for the current, ensuring that the energy in the inductor can be smoothly transferred to the output end without current interruption and excessive reverse electromotive force generated by the inductor due to the disconnection of the switch, thereby protecting the circuit components from damage, while ensuring that the energy is transmitted in the designed direction to achieve stable voltage increase or decrease.

[0041] Specifically, the eighth switch device V1 and the ninth switch device V2 are voltage sensors or voltage-dividing resistors. When the voltage of the energy storage battery reaches a full or fully discharged threshold, the control circuit can stop the charging or discharging process in time to protect the life of the energy storage battery. The eighth impedance RS1 is a current sensor or a sampling resistor. During the charging process, when it is detected that the charging current is too large, the control circuit can reduce the charging current in time to prevent the energy storage battery from being overcharged and the circuit components from being damaged due to overcurrent. During the discharging process, according to the size of the load current, the control circuit can adjust the output current of the buck-boost unit 106 to meet the load demand while ensuring the safe operation of the circuit.

[0042] Specifically, the tenth switch device K1 is a mechanical switch or an electronic switch, which can be a relay or a MOS tube. When it is necessary to power a load such as an air conditioner, K1 and K2 are closed so that the bus voltage can be transmitted to the first boost unit 102, thereby providing electrical energy to the load. When it is not necessary to power the load, the switch is disconnected to cut off the circuit to prevent energy waste and accidental short circuits, thereby ensuring the safety and reliability of the circuit. The eleventh switch device K4 is a mechanical switch or an electronic switch, and it is determined whether to connect the photovoltaic input to the circuit according to actual conditions. For example, when there is sufficient sunlight during the day, K3 and K4 are closed so that the electrical energy generated by the photovoltaic panel can enter the second boost unit 104 for processing and storage. At night or when there is insufficient light, the switch is disconnected to avoid unnecessary current paths in the circuit, thereby ensuring the normal operation of the circuit and the safety of the equipment.

[0043] From the above, it can be seen that in the embodiment of the present application, the direct current power input by the photovoltaic power is converted into a voltage suitable for energy storage and inversion, and the voltage is increased or decreased by the second boost unit and the boost-buck unit to ensure the effective conversion of electric energy between different voltage levels. The storage and release of electric energy is achieved through the charging and discharging of the energy storage battery to improve the energy utilization efficiency. The first boost unit is used to ensure that the load can obtain a stable voltage supply, thereby improving the working efficiency and life of the load.

[0044] According to another aspect of the present application, a control method of any one of the above-mentioned charge and discharge circuits is provided. Figure 3 FIG. 1 is a flow chart of a control method for a charge and discharge circuit according to an embodiment of the present application. Figure 3 As shown, the method comprises the following steps:

[0045] Step S201, acquiring input power of a first photovoltaic component to obtain a first power, and acquiring input power of a second photovoltaic component to obtain a second power.

[0046] Specifically, by obtaining the input power of the first photovoltaic component and the input power of the second photovoltaic component, the system can monitor the output of the photovoltaic components in real time, so as to adjust the working state of the charging and discharging circuit according to the actual situation. By monitoring the input power of the photovoltaic components, the charging and discharging speed of the charging and discharging circuit can be controlled in real time, which provides basic data for subsequent judgment on whether the system can meet the power demand of loads such as electrical equipment, and helps to coordinate the relationship between photovoltaic power generation and load operation.

[0047] Step S202, obtaining the remaining power of the energy storage battery, and determining whether to control the electrical equipment to work, and in the case of controlling the electrical equipment to work, determining whether the sum of the first power and the second power is greater than the rated power of the electrical equipment.

[0048] Specifically, the remaining power of the energy storage battery is obtained so that the system can comprehensively consider the energy status of photovoltaic power generation and the energy storage battery to determine whether it can support the operation of the electrical equipment. By determining whether the sum of the first power and the second power is greater than the rated power of the electrical equipment, it can help avoid overloading the electrical equipment. It can determine whether the current photovoltaic power generation is sufficient to support the operation of the electrical equipment alone. If it is greater than the rated power, it indicates that photovoltaic power generation can meet the load demand to a certain extent. If it is less than or equal to the rated power, the assistance of the energy storage battery may be required to protect the circuit and equipment from damage, which helps to reasonably allocate energy.

[0049] Step S203, when the sum of the first power and the second power is greater than the rated power of the electrical device, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the maximum value of the remaining power.

[0050] Specifically, by controlling the operation of the boost and buck units according to the relationship between the remaining power and the maximum remaining power, the efficiency and stability of the circuit can be effectively improved, the service life of the equipment can be extended, and at the same time, the circuit can be ensured to operate within an appropriate voltage range to reduce energy waste. The charging and discharging circuit can be ensured to operate stably within the rated power range to avoid overload or underload. The working status of each unit of the circuit can be flexibly adjusted according to the energy reserve situation and power generation capacity.

[0051] Step S204, when the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, control the operation of at least two of the first boost unit, the second boost unit and the buck-boost unit according to the relationship between the remaining power and the minimum remaining power.

[0052] Specifically, by controlling the operation of at least two boost units and a buck-boost unit, the working state of the circuit can be dynamically adjusted according to the relationship between the remaining power and the minimum power, ensuring that the electrical equipment maintains normal operation while maximizing the battery life, and ensuring that the remaining power is effectively utilized within the rated power range of the electrical equipment to avoid power shortage or waste. The energy efficiency of the circuit can be effectively improved, the battery life can be extended, and the normal operation of the electrical equipment can be ensured, thereby improving the stability and reliability of the system.

[0053] Through this embodiment, the air conditioner is powered by the buck-boost unit to the bus, and can also be charged by the pure energy storage battery through the buck-boost unit; the energy storage battery is powered by the air conditioner through the buck-boost unit to the bus; in addition, the second group of photovoltaic components is powered by the air conditioner through the second boost unit to the bus; compared with the two-way charging and discharging circuit that only includes one photovoltaic component in the prior art, the present application can optimize the power supply mode and improve the charging efficiency.

[0054] Figure 4 is a flow chart of a method for controlling a charging and discharging circuit when an air conditioner is turned on according to an embodiment of the present application. Figure 4 As shown, the air conditioner first performs a self-check before starting up. If there is no abnormality, it enters data collection. Through the voltage and current detection circuit, the voltage and current data are averaged multiple times to obtain the photovoltaic panel voltage value U 1 , U 2 With current value I 1 ,I 2 , calculate the first group of photovoltaic input power P 1 , the second group of photovoltaic input power P 2 , and judge whether the following formula P is satisfied 1 +P 2 >P 0 , where P 2 =U 2 I 2 , P 1 =U 1 I 1 , P 0 Rated power of the air conditioner.

[0055] In the specific implementation process, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device and an eleventh switch device. When the sum of the first power and the second power is greater than the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the maximum value of the remaining power. This can be achieved by the following steps: when the remaining power is less than the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device and the tenth switch device are controlled to operate; when the remaining power is greater than or equal to the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device and the eleventh switch device are controlled to operate.

[0056] In this solution, different switching devices can be effectively controlled to work according to the amount of remaining power to achieve the best power management effect. By controlling the operation of different switching devices, the circuit can adjust the flow direction and conversion method of energy according to the current low power of the energy storage battery, and can realize the boost and buck functions of the circuit, so as to better match the rated power requirements of the electrical equipment. By selecting different switch combinations to control the circuit operation according to the amount of remaining power, the distribution of energy can be optimized, the battery life can be effectively extended, the efficiency and stability of the circuit can be improved, the performance of the charging and discharging circuit can be effectively optimized, and the use efficiency and energy-saving effect of the electrical equipment can be improved.

[0057] Specifically, if the condition P is satisfied 1 +P 2 >P 0 Then the battery power SOC (State of Charge) is judged, that is, the proportion of the current power stored in the battery to its total capacity. The battery sends the SOC value to the main chip through CAN communication (Controller Area Network) between the photovoltaic energy storage inverter. If the SOC value is satisfied, <SOC max , where SOC max It is the preset battery charge threshold, which can be 100%. Its function is to protect the battery life and avoid overcharging. The main chip controls the relay K 1 , K 2 , K 3 Turn on, switch tube V 2 、V 3 、V 4 When the battery is working, it enters charging mode and the air conditioner runs at rated power at the same time; otherwise, the battery enters charging protection state and does not work, and the air conditioner runs at rated power.

[0058] In the specific implementation process, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes an eighth switch device and a tenth switch device. When the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, at least two of the first boost unit, the second boost unit and the buck-boost unit are controlled to work according to the relationship between the remaining power and the minimum value of the remaining power. This can be achieved by the following steps: when the remaining power is greater than the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the eighth switch device and the tenth switch device are controlled to work; when the remaining power is less than or equal to the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device and the sixth switch device are controlled to work.

[0059] In this scheme, the working state of the charging and discharging circuit can be effectively controlled according to the size relationship between the remaining power and the minimum remaining power, ensuring that the working mode can be automatically adjusted to ensure the normal operation of the equipment when the power is insufficient. By controlling the working combination of different switching devices, the circuit can be boosted, bucked, and buck-boosted, thereby effectively adjusting the output voltage to meet the rated power requirement of the equipment, which can improve the energy efficiency of the equipment, extend the service life of the equipment, and improve the stability and reliability of the equipment.

[0060] Specifically, if the formula P is not satisfied 1 +P 2 >P 0, then enter the battery power SOC judgment, if SOC>SOC min , where SOC min It is the preset battery discharge threshold, which can be 20%, to protect the battery life and avoid the situation of full discharge. The main chip controls the relay K 1 , K 2 , K 3 Turn on, switch tube V 1 、V 3 、V 4 When the battery is working, it enters the discharge mode and the air conditioner runs at rated power; otherwise, the battery enters the discharge protection state and does not work, and the air conditioner runs at reduced power.

[0061] In the specific implementation process, the photovoltaic energy storage system also includes electrical equipment. After determining whether to control the electrical equipment to work, the above method also includes the following steps: when the electrical equipment is controlled not to work, determining whether the sum of the first power and the second power is greater than the rated power of the electrical equipment; when the sum of the first power and the second power is greater than the rated power of the electrical equipment, controlling the first boost unit, the second boost unit and the buck-boost unit to work according to the relationship between the remaining power and the maximum value of the remaining power; when the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, controlling the first boost unit, the second boost unit and the buck-boost unit to work according to the relationship between the remaining power and the minimum value of the remaining power.

[0062] In this solution, the working state of electrical equipment in the photovoltaic energy storage system is effectively controlled according to the current power demand and remaining power of the system to ensure stable operation of the system and maximize the use of renewable energy. By dynamically adjusting the working state of the boost and buck units, the power demand and power reserve of the system can be effectively balanced, energy utilization efficiency can be improved, and the service life of the system can be extended. At the same time, it can also reduce dependence on the external power grid and reduce energy costs.

[0063] Specifically, for the situation where the air conditioner is not turned on, such as in spring and autumn when the weather is neither cold nor hot, and the air conditioner does not need to be turned on, the air conditioner only needs to be put on standby, and only the BOOST boost circuit (i.e., the first boost unit) on the air conditioner works. The air conditioner is in standby mode and enters the battery power SOC judgment.

[0064] In the specific implementation process, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device and an eleventh switch device. When the sum of the first power and the second power is greater than the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the maximum value of the remaining power. This can be achieved by the following steps: when the remaining power is less than the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device, the tenth switch device and the eleventh switch device are controlled to operate; when the remaining power is greater than or equal to the maximum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device and the eleventh switch device are controlled to operate.

[0065] In this solution, flexible control of each switching device in the charging and discharging circuit can be achieved, and different working states can be determined according to the amount of remaining power, effectively protecting electrical equipment and extending its service life. When the remaining power is low, sufficient voltage can be provided to support the normal operation of the electrical equipment by controlling multiple switching devices at the same time. When the remaining power is high, energy can be saved and losses can be reduced by reducing the operation of the switching devices. While ensuring the normal operation of the electrical equipment, it can maximize energy utilization efficiency and realize intelligent charging and discharging management.

[0066] Specifically, if SOC is met <SOC max , then the main chip controls relay K 1 , K 2 , K 3 , K 4 Turn on, switch tube V 2 、V 3 、V 4 Work, charge the battery, and power the household appliances through the inverter; on the contrary, the main chip controls the relay K 2 , K 3 , K 4 Turn on, switch tube V 2 、V 3 、V 4 When working, the battery enters the charging protection state and does not work, only supplying power to household appliances.

[0067] In the specific implementation process, the first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device and an eleventh switch device. When the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the minimum value of the remaining power. This can be achieved by the following steps: when the remaining power is greater than the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device, the tenth switch device and the eleventh switch device are controlled to operate; when the remaining power is less than or equal to the minimum value of the remaining power, the first switch device, the third switch device, the fifth switch device, the sixth switch device and the ninth switch device are controlled to operate.

[0068] In this scheme, the working states of different step-up and step-down units can be effectively adjusted according to the size relationship between the remaining power and the minimum value of the remaining power, so as to realize effective management of the rated power of the electrical equipment. By controlling the working states of different switching devices, the remaining power can be utilized to the maximum extent while ensuring the stable operation of the system, the service life of the electrical equipment can be extended, and the energy utilization efficiency can be improved. It can also effectively avoid the situation where the electrical equipment cannot work normally due to insufficient remaining power, thereby improving the reliability and stability of the system.

[0069] Specifically, when the photovoltaic input is insufficient, if SOC>SOC min , main chip control relay K 1 , K 2 , K 3 , K 4 The inverter works and the battery compensates for the power required by the household appliances. On the contrary, the eighth control module enters the discharge protection state and does not work. The power required by household appliances should not be higher than the power that the battery and photovoltaic can provide, so as to avoid safety hazards.

[0070] In addition, it should be noted that the above voltage and current detection is real-time. After the main chip gives the corresponding drive signal according to the current detection value, so that the photovoltaic energy storage converter works in the corresponding working state, it will enter data sampling at the next moment, and execute the above steps in a loop, giving a signal in real time according to the detection value. If a certain voltage or current exceeds the protection value, the main chip will send a signal to control the relay K. 1 , K 2 , K 3 , K 4 Close, air conditioning protection shutdown.

[0071] Figure 4is a schematic diagram of a photovoltaic energy storage air conditioning system according to an embodiment of the present application, such as Figure 4 As shown, the output of the first group of photovoltaic panels is connected to the outdoor unit of the air conditioner through interfaces PV+ and PV-, filtered by the filter board, and the voltage of the outdoor unit main board is boosted and connected to the photovoltaic energy storage inverter through interfaces P+ and P-. The output of the second group of photovoltaic panels is directly connected to the photovoltaic energy storage inverter through interfaces IN+ and IN-. After three-way charging and discharging circuits, the photovoltaic energy storage inverter is connected to the battery through interfaces BAT+ and BAT-, and the photovoltaic energy storage inverter is connected to the household appliances through the inverter.

[0072] The technical solution provided by the above-mentioned embodiment of the present invention, compared with the traditional two-way bidirectional photovoltaic energy storage inverter, can increase the charging power and improve the charging efficiency when a single group of photovoltaics is sufficient; when a single group of photovoltaics is insufficient and two groups of photovoltaics are sufficient, the power supply mode can be optimized to allow the second group of photovoltaic panels to completely power the air conditioner, and part of the power generated by the first group of photovoltaic panels compensates the air conditioner, and part of it is used to charge the battery; when the two groups of photovoltaics are insufficient, both groups of photovoltaic panels power the air conditioner, and the battery compensates the air conditioner. In particular, in some situations where air conditioning is not needed, the battery and household appliances are directly powered by opening and closing the relay and the inverter.

[0073] As can be seen from the above, in the embodiment of the present invention, a three-way photovoltaic energy storage inverter charging and discharging circuit is adopted, and two groups of photovoltaic panels are used. Each group of photovoltaic panels consists of 7 photovoltaic panels connected in series, with an open circuit voltage of about 350Vdc and a maximum current of 13A. Theoretically, the output power can reach 3500W when the light is sufficient. The first group of 7 photovoltaic panels supplies power to the air conditioner, and the second group of 7 photovoltaic panels supplies power to the photovoltaic energy storage inverter. The photovoltaic energy storage inverter is connected to the battery and the air conditioner at the same time. When the photovoltaic power is sufficient, the first group of photovoltaic panels supplies power to the air conditioner and charges the battery at the same time, and the second group also charges the battery. The total charging power is high and the charging is fast. When the photovoltaic power is insufficient, the second group of photovoltaic panels completely supplies power to the air conditioner, and part of the power generated by the first group of photovoltaic panels compensates the air conditioner, and part of it charges the battery. The power supply mode can be optimized and the charging efficiency can be improved. In the standby state of the air conditioner, the battery can be directly charged to power household appliances.

[0074] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0075] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0076] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0077] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0078] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0079] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0080] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0081] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0082] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0083] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A charging and discharging circuit, characterized in that: Applied to a photovoltaic energy storage system, the photovoltaic energy storage system includes a first photovoltaic component, a second photovoltaic component, an energy storage battery and an electrical device, the charging and discharging circuit includes a first boost unit, a second boost unit and a buck-boost unit, wherein the output end of the first boost unit is electrically connected to the output end of the buck-boost unit, the output end of the second boost unit is electrically connected to the output end of the buck-boost unit, the first boost unit is used to boost the output signal of the first photovoltaic component, and the first boost unit is located in the electrical device, the second boost unit is used to boost the output signal of the second photovoltaic component, and the buck-boost unit is used to boost or buck the output signal of the energy storage battery.

2. The charge and discharge circuit according to claim 1, characterized in that: The first boost unit includes a first impedance, a first switching device, a second switching device, a third switching device and a second impedance, wherein the first end of the first impedance is electrically connected to the second end of the first switching device, the first end of the first switching device, the first end of the second switching device and the first end of the third switching device are electrically connected, the second end of the third switching device is electrically connected to the first end of the second impedance, the second end of the first impedance and the second end of the second impedance are input ends of the first boost unit, and the second end of the second switch device is the output end of the first boost unit.

3. The charge and discharge circuit according to claim 1, characterized in that: The second boost unit includes a third impedance, a fourth switch device, a fifth switch device, a sixth switch device, a fourth impedance and a fifth impedance, wherein the second end of the third impedance is electrically connected to the first end of the fourth switch device, the second end of the fourth switch device, the first end of the fifth switch device and the first end of the sixth switch device are electrically connected, the second end of the sixth switch device is electrically connected to the first end of the fifth impedance, the second end of the fifth switch device is electrically connected to the first end of the fourth impedance, the second end of the fourth impedance is the output end of the second boost unit, and the first end of the third impedance and the second end of the fifth impedance are the input ends of the second boost unit.

4. The charge and discharge circuit according to claim 1, characterized in that: The buck-boost unit includes a sixth impedance, a seventh impedance, a seventh switch device, an eighth switch device, an eighth impedance, a ninth switch device, a ninth impedance, a tenth switch device and an eleventh switch device, wherein a first end of the tenth switch device, a first end of the eleventh switch device, a first end of the sixth impedance and a first end of the seventh impedance are electrically connected, a second end of the tenth switch device and a second end of the sixth impedance are input ends of the buck-boost unit, a second end of the seventh impedance, a first end of the seventh switch device and a first end of the eighth switch device are electrically connected, a second end of the eighth switch device is electrically connected to a first end of the eighth impedance, a second end of the seventh switch device is electrically connected to a first end of the ninth switch device, a second end of the ninth switch device is electrically connected to a first end of the ninth impedance, and a second end of the ninth impedance is electrically connected to a second end of the eighth impedance.

5. A control method for a charge and discharge circuit according to any one of claims 1 to 4, characterized in that: include: Acquiring input power of the first photovoltaic component to obtain a first power, and acquiring input power of the second photovoltaic component to obtain a second power; Obtaining the remaining power of the energy storage battery, and determining whether to control the electrical device to work, and in the case of controlling the electrical device to work, determining whether the sum of the first power and the second power is greater than the rated power of the electrical device; When the sum of the first power and the second power is greater than the rated power of the electrical device, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the magnitude relationship between the remaining power and the maximum value of the remaining power; When the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, the operation of the first boost unit, the second boost unit and at least two of the buck-boost units are controlled according to the relationship between the remaining power and the minimum value of the remaining power.

6. The method according to claim 5, characterized in that The first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device, and an eleventh switch device. When the sum of the first power and the second power is greater than the rated power of the electrical device, the first boost unit, the second boost unit, and the buck-boost unit are controlled to operate according to the magnitude relationship between the remaining power and the maximum value of the remaining power, including: When the remaining power is less than the maximum value of the remaining power, controlling the first switching device, the third switching device, the fifth switching device, the sixth switching device, the ninth switching device and the tenth switching device to operate; When the remaining power is greater than or equal to the maximum value of the remaining power, the first switching device, the third switching device, the fifth switching device, the sixth switching device, the ninth switching device and the eleventh switching device are controlled to operate.

7. The method according to claim 5, characterized in that The first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes an eighth switch device and a tenth switch device. When the sum of the first power and the second power is less than or equal to the rated power of the electrical device, at least two operations of the first boost unit, the second boost unit, and the buck-boost unit are controlled according to the magnitude relationship between the remaining power and the minimum value of the remaining power, including: When the remaining power is greater than the minimum value of the remaining power, controlling the first switching device, the third switching device, the fifth switching device, the sixth switching device, the eighth switching device and the tenth switching device to operate; When the remaining power is less than or equal to the minimum value of the remaining power, the first switching device, the third switching device, the fifth switching device, and the sixth switching device are controlled to operate.

8. The method according to claim 5, characterized in that After determining whether to control the electrical device to operate, the method further includes: In a case where the electrical device is controlled not to work, determining whether the sum of the first power and the second power is greater than a rated power of the electrical device; When the sum of the first power and the second power is greater than the rated power of the electrical device, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the magnitude relationship between the remaining power and the maximum value of the remaining power; When the sum of the first power and the second power is less than or equal to the rated power of the electrical equipment, the first boost unit, the second boost unit and the buck-boost unit are controlled to operate according to the relationship between the remaining power and the minimum value of the remaining power.

9. The method according to claim 8, characterized in that The first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device, and an eleventh switch device. When the sum of the first power and the second power is greater than the rated power of the electrical device, the first boost unit, the second boost unit, and the buck-boost unit are controlled to operate according to the magnitude relationship between the remaining power and the maximum value of the remaining power, including: When the remaining power is less than the maximum value of the remaining power, controlling the first switching device, the third switching device, the fifth switching device, the sixth switching device, the ninth switching device, the tenth switching device and the eleventh switching device to operate; When the remaining power is greater than or equal to the maximum value of the remaining power, the first switching device, the third switching device, the fifth switching device, the sixth switching device, the ninth switching device and the eleventh switching device are controlled to operate.

10. The method according to claim 8, characterized in that The first boost unit includes a first switch device and a third switch device, the second boost unit includes a fifth switch device and a sixth switch device, and the buck-boost unit includes a ninth switch device, a tenth switch device, and an eleventh switch device. When the sum of the first power and the second power is less than or equal to the rated power of the electrical device, the first boost unit, the second boost unit, and the buck-boost unit are controlled to operate according to the magnitude relationship between the remaining power and the minimum value of the remaining power, including: When the remaining power is greater than the minimum value of the remaining power, controlling the first switch device, the third switch device, the fifth switch device, the sixth switch device, the ninth switch device, the tenth switch device and the eleventh switch device to operate; When the remaining power is less than or equal to the minimum value of the remaining power, the first switching device, the third switching device, the fifth switching device, the sixth switching device and the ninth switching device are controlled to operate.

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