Control Circuit, Method, and Photovoltaic Energy Storage Control System of a Filtering Circuit

Abstract

The present invention provides a control circuit, method, and photovoltaic storage control system for a filter circuit, wherein the control circuit of the filter circuit includes: an acquisition circuit connected to an external power grid for collecting power supply information from the external power grid; a controller connected to the acquisition circuit for determining the operating state of the photovoltaic storage system based on the power supply information, wherein the operating state is used to characterize the power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and electrical equipment; and a filter circuit connected between the controller and the AC / DC converter of the photovoltaic storage system for adjusting the filtering mode between the external power grid and the photovoltaic storage system based on the operating state. The present invention solves the technical problem of high energy loss in photovoltaic storage systems in related technologies, reduces energy loss, and improves the energy utilization and stability of photovoltaic storage systems.

Description

Technical Field

[0001] The present invention relates to the field of circuits, and in particular to a control circuit and method for a filter circuit, and a light storage control system. Background Art

[0002] In the related technologies, the existing solar-storage air-conditioning system has been widely used and is a good application system for collecting and absorbing new energy on site; however, there are also some shortcomings, which limit the application of the air-conditioning system.

[0003] There are many different operating modes for the photovoltaic storage air conditioning system, and the operating conditions are complex and changeable, including: when connected to the grid and with the mains, the photovoltaic storage air conditioning system generates the largest amount of power, and after meeting the needs of air conditioning, it also supplies power to local loads and generates power to the grid; when connected to the grid and with the mains, the photovoltaic storage air conditioning system generates the smallest amount of power, which cannot meet the needs of air conditioning, and the grid provides most of the power to the photovoltaic storage air conditioning system; when connected to the grid and with the mains, the photovoltaic storage air conditioning system generates a large amount of power, but it cannot meet the needs of air conditioning, and the grid provides a small amount of power to the photovoltaic storage air conditioning system; when connected to the grid and with the mains, the photovoltaic storage air conditioning system generates a large amount of power, but it cannot meet the needs of air conditioning, and the grid provides a small amount of power to the photovoltaic storage air conditioning system. All the power generated can meet the needs of air conditioning and is in an energy balance state. There is no power exchange between the power grid and the photovoltaic storage air conditioning system; when off-grid, without the mains power, the photovoltaic storage air conditioning system has the largest power generation capacity. After meeting the needs of air conditioning, the photovoltaic storage air conditioning system supplies power to the local load; when off-grid, without the mains power, the power generation capacity of the photovoltaic storage air conditioning system is the smallest and cannot meet the needs of air conditioning. The local power generation equipment provides most of the power to the photovoltaic storage air conditioning system; when off-grid, without the mains power, the power generation capacity of the photovoltaic storage air conditioning system is large, but it cannot meet the needs of air conditioning. The local power generation equipment provides a small part of the power to the photovoltaic storage air conditioning system.

[0004] Solar-storage air-conditioning systems have a variety of operating modes and complex and changeable operating conditions. The filter circuits of the AC / DC converters connected to the power grid generally have a fixed topology design and do not change, making it difficult to meet the various operating modes of the solar-storage air-conditioning system. This results in large losses in the entire system, unoptimized parameters, power waste, and low operational stability.

[0005] Currently, no effective solution has been found for the above-mentioned problems existing in the related technologies. Summary of the Invention

[0006] The embodiments of the present invention provide a control circuit and method of a filter circuit, and a photovoltaic storage control system to solve the technical problem of large energy loss in photovoltaic storage systems in related technologies.

[0007] According to one embodiment of the present invention, a control circuit of a filtering circuit is provided, comprising: an acquisition circuit connected to an external power grid, for acquiring power supply information of the external power grid; a controller connected to the acquisition circuit, for determining an operating state of a photovoltaic storage system based on the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and electrical equipment; and a filtering circuit connected between the controller and an AC / DC converter of the photovoltaic storage system, for adjusting a filtering mode between the external power grid and the photovoltaic storage system according to the operating state.

[0008] Optionally, the controller includes: a determination module for determining the distribution network status of the photovoltaic storage system based on the power supply information, wherein the distribution network status includes: an off-grid state or a grid-connected state; a calculation module for calculating the active power emitted by the AC / DC converter under the current distribution network status based on the power supply information; and an adjustment module for sending a control signal to the filtering circuit based on the distribution network status and the active power, wherein the control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system.

[0009] Optionally, the adjustment module further includes: a first adjustment unit for sending a first control signal when the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device in a grid-connected state, wherein the first control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LCL filtering; a second adjustment unit for sending a second control signal when the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is greater than a first threshold value in a grid-connected state, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to a first L filtering; a third adjustment unit for sending a third control signal when the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is less than a second threshold value in a grid-connected state for adjusting the filtering mode between the external power grid and the photovoltaic storage system to a first L filtering. The filtering mode between the photovoltaic storage system is the second L filtering; the fourth adjustment unit is used to send the third control signal when the power generation of the photovoltaic panel is equal to the power consumption of the power consumer in the grid-connected state; the fifth adjustment unit is used to send the fourth control signal when the power generation of the photovoltaic panel is greater than the power consumption of the power consumer in the off-grid state, wherein the fourth control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LC filtering; the sixth adjustment unit is used to send the second control signal when the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is greater than the third threshold in the off-grid state; the seventh adjustment unit is used to send the third control signal when the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is less than the fourth threshold in the off-grid state.

[0010] Optionally, the filter inductance of the first L filter is greater than the filter inductance of the second L filter.

[0011] Optionally, the filtering circuit includes: a first inductor, whose first port is connected to the AC / DC converter; a second inductor, whose first port is connected to the second port of the first inductor, and whose second port is connected to the external power grid; a first switch, connected between the two ports of the first inductor, and used to control the access state of the first inductor according to the control signal of the controller; a second switch, connected between the two ports of the second inductor, and used to control the access state of the second inductor according to the control signal of the controller; a first capacitor, whose first port is grounded, and whose second port is connected to a connection path between the second port of the first inductor and the first port of the second inductor through a third switch; a third switch, connected between the second port of the second inductor and the connection path, and used to control the access state of the first capacitor according to the control signal of the controller.

[0012] Optionally, the inductance of the first inductor is greater than the inductance of the second inductor.

[0013] Optionally, the filtering modes include: L filtering, LC filtering, and LCL filtering.

[0014] Optionally, the acquisition circuit includes: a first acquisition module, used to acquire the voltage signal of the external power grid; and a second acquisition module, used to acquire the current signal of the external power grid.

[0015] According to one embodiment of the present invention, a photovoltaic storage control system is also provided, which includes: a control circuit, including a control circuit of the filter circuit described in the above embodiment; a photovoltaic storage system, connected to the control circuit through an AC / DC converter, including photovoltaic panels and electrical equipment; a grid switch, connected between the control circuit and the AC mains, for controlling the access status of the AC mains.

[0016] According to another embodiment of the present invention, a control method for a filtering circuit is provided, comprising: collecting power supply information of an external power grid; determining an operating state of a photovoltaic storage system based on the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and electrical equipment; and adjusting a filtering mode between the external power grid and the photovoltaic storage system based on the operating state.

[0017] Optionally, determining the operating status of the photovoltaic storage system based on the power supply information includes: determining the distribution network status of the photovoltaic storage system based on the power supply information, wherein the distribution network status includes: off-grid status or grid-connected status; calculating the active power emitted by the AC / DC converter of the photovoltaic storage system under the current distribution network status based on the power supply information; sending a control signal to the filtering circuit based on the distribution network status and the active power, wherein the control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system.

[0018] Optionally, sending a control signal to the filtering circuit according to the distribution network status and the active power includes: in the grid-connected state, the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, sending a first control signal, wherein the first control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LCL filtering; in the grid-connected state, the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is greater than a first threshold, sending a second control signal, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to the first L filtering; in the grid-connected state, the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is less than a second threshold, sending a third control signal. The signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to the second L filtering; in the grid-connected state, the power generation of the photovoltaic panel is equal to the power consumption of the power consumer, and the third control signal is sent; in the off-grid state, the power generation of the photovoltaic panel is greater than the power consumption of the power consumer, and the fourth control signal is sent, wherein the fourth control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LC filtering; in the off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is greater than the third threshold, and the second control signal is sent; in the off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is less than the fourth threshold, and the third control signal is sent.

[0019] Optionally, the external power grid also includes: local power generation equipment, which is connected to the photovoltaic storage system through the control circuit, and is used to power the photovoltaic storage system when it is off-grid and the power generation of the photovoltaic panel is less than the power consumption of the power-consuming equipment.

[0020] Through the present invention, the acquisition circuit acquires power supply information of the external power grid, the controller determines the operating state of the photovoltaic storage system based on the power supply information, and the filter circuit connected between the controller and the AC / DC converter of the photovoltaic storage system adjusts the filtering mode between the external power grid and the photovoltaic storage system according to the operating state. By acquiring the power supply information of the external power grid and scheduling communication with the AC / DC converter, the switching control of the filter circuit is performed, so that the filter circuit of the AC / DC converter connected to the photovoltaic storage system and the power grid can automatically adapt and adjust the filtering mode under different working conditions of the photovoltaic storage system being connected to the grid and being off-grid, thereby ensuring that the photovoltaic storage system is always in the optimal state, solving the technical problem of large energy loss of the photovoltaic storage system in the related art, reducing energy loss, and improving the energy utilization rate and stability of the photovoltaic storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 is a structural diagram of a control circuit of a filter circuit according to an embodiment of the present invention;

[0023] Figure 2 is a system topology diagram of an embodiment of the present invention;

[0024] Figure 3 is a control schematic diagram of an embodiment of the present invention;

[0025] Figure 4 is a system topology diagram of an embodiment of the present invention in operation mode 1;

[0026] Figure 5 This is a system topology diagram of an embodiment of the present invention in operation mode 2;

[0027] Figure 6 This is a system topology diagram of an embodiment of the present invention in operation mode three;

[0028] Figure 7 is a system topology diagram of an embodiment of the present invention in operation mode 4;

[0029] Figure 8 This is a system topology diagram of an embodiment of the present invention in operation mode five;

[0030] Figure 9 is a system topology diagram of an embodiment of the present invention in operation mode six;

[0031] Figure 10 This is a system topology diagram of an embodiment of the present invention in operation mode seven. DETAILED DESCRIPTION

[0032] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and Examples. It should be understood that the specific embodiments described herein are only intended to explain the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention.

[0033] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, the elements defined by the phrase "comprising..." do not exclude the presence of other identical elements in the process, method, article, or device comprising the elements.

[0034] Example 1

[0035] In this embodiment, a control circuit for a filter circuit is provided. Figure 1 FIG. 1 is a structural diagram of a control circuit of a filter circuit according to an embodiment of the present invention. Figure 1 As shown, including:

[0036] The acquisition circuit 10 is connected to the external power grid and is used to collect power supply information of the external power grid;

[0037] Optionally, the external power grid includes an AC mains grid and local power generation equipment.

[0038] a controller 12, connected to the acquisition circuit, for determining an operating state of the photovoltaic storage system based on the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and electrical equipment;

[0039] Optionally, the solar storage system of this embodiment can be a solar storage air conditioning system, a solar storage refrigerator system, a solar storage lighting system, a solar storage water heater system, etc. This embodiment is described by taking the solar storage air conditioning system as an example.

[0040] The filtering circuit 14 is connected between the controller and the AC / DC converter of the photovoltaic storage system, and is used to adjust the filtering mode between the external power grid and the photovoltaic storage system according to the working state.

[0041] The filter circuit 14 may be a part of the AC / DC converter, or a circuit connected to the original AC / DC converter to form an AC / DC converter with a changeable topology structure according to this embodiment.

[0042] Through the above circuit, the acquisition circuit acquires the power supply information of the external power grid, the controller determines the working state of the photovoltaic storage system according to the power supply information, and the filter circuit connected between the controller and the AC / DC converter of the photovoltaic storage system adjusts the filtering mode between the external power grid and the photovoltaic storage system according to the working state. By acquiring the power supply information of the external power grid and scheduling communication with the AC / DC converter, the switching control of the filter circuit is performed, so that the photovoltaic storage system can automatically adapt and adjust the filtering mode of the AC / DC converter connected to the power grid under different working conditions of being connected to the grid and being off-grid, thereby ensuring that the photovoltaic storage system is always in the optimal state, solving the technical problem of large energy loss of the photovoltaic storage system in the related technology, reducing energy loss, and improving the energy utilization and stability of the photovoltaic storage system.

[0043] The acquisition circuit 10, controller 12 and filter circuit 14 can be implemented by any combination of circuits, integrated circuits, or microprocessors that can achieve the above functions. To make the description of the embodiments of the present invention clearer, the embodiments of the present invention will be described and illustrated below in conjunction with the preferred embodiments.

[0044] In this embodiment, the filtering modes include: L filtering, LC filtering, and LCL filtering. These three filtering modes correspond to three circuit topologies. The single-inductor L-type filter is a filtering method commonly used for grid-connected converters. It features a simple structure and is easy to control, but its filtering effect on high-frequency harmonic components is limited. The larger the inductance, the better the high-frequency harmonic suppression effect. The LC-type filter is another filtering method for grid-connected converters. Its effect in the low-frequency band is similar to that of the single-L-type filter, and its effect in the high-frequency band is better. It performs best in off-grid conditions. The LCL-type filter is another filtering method for grid-connected converters. Its effect in the low-frequency band is similar to that of the single-L-type filter, and its effect in the high-frequency band is the best of the three types of filters. Its performance in off-grid conditions is average. Overall, it will have resonance peaks, making control and debugging difficult. In extreme cases, it may cause failures or poor filtering effects.

[0045] In one implementation of this embodiment, the filtering circuit includes: a first inductor, whose first port is connected to the AC / DC converter; a second inductor, whose first port is connected to the second port of the first inductor, and whose second port is connected to the external power grid; a first switch, connected between the two ports of the first inductor, and used to control the access state of the first inductor according to the control signal of the controller; a second switch, connected between the two ports of the second inductor, and used to control the access state of the second inductor according to the control signal of the controller; a first capacitor, whose first port is grounded, and whose second port is connected to a connection path between the second port of the first inductor and the first port of the second inductor through a third switch; and a third switch, connected between the second port of the second inductor and the connection path, and used to control the access state of the first capacitor according to the control signal of the controller.

[0046] Optionally, the inductance of the first inductor is greater than the inductance of the second inductor.

[0047] Optionally, the acquisition circuit includes: a first acquisition module, used to acquire the voltage signal of the external power grid; and a second acquisition module, used to acquire the current signal of the external power grid.

[0048] Figure 2 This is a system topology diagram of an embodiment of the present invention. The solid line frame is a photovoltaic air-conditioning system (a type of photovoltaic storage system), which includes energy storage batteries, solar photovoltaic panels, air-conditioning compressors, AC / DC converters and DC / AC converters, and DC / DC converters; the AC / DC converter is responsible for energy interaction with the power grid and local loads; the DC / AC converter is responsible for driving the air-conditioning compressor; the DC / DC converter is responsible for charging and discharging the energy storage battery; the inductor L1 (first inductor), the inductor L2 (second inductor), and the capacitor C1 (first capacitor) constitute the filter circuit of the AC / DC converter (optionally, the inductance of L1 is larger than that of L2, and the equivalent impedance is also relatively large), which can constitute L, LC, and LCL circuit topologies; K0 is a switch connected to the power grid.

[0049] The filter circuit system controller (a type of controller) is responsible for collecting and controlling the AC grid voltage signal (U_gird_abc) and the AC grid current signal (I_gird_abc), and performing harmonic analysis. It also controls switches K1 (first switch), K2 (second switch), and K3 (third switch), switching them on and off. It also coordinates and communicates with the AC / DC converter of the solar-storage air conditioning system. It should be noted that this embodiment uses a three-phase system as an example; single-phase AC systems have similar characteristics, and the control method is universal.

[0050] In one implementation of this embodiment, the controller includes: a determination module for determining the distribution network status of the photovoltaic storage system based on the power supply information, wherein the distribution network status includes: an off-grid state or a grid-connected state; a calculation module for calculating the active power emitted by the AC / DC converter in the current distribution network status based on the power supply information; an adjustment module for sending a control signal to the filtering circuit based on the distribution network status and the active power, wherein the control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system.

[0051] Optionally, the adjustment module includes multiple adjustment units, which are respectively used to control the switching states of the above-mentioned switches K1, K2, and K3 under corresponding working conditions, and adjust the filtering mode between the external power grid and the photovoltaic storage system. The adjustment module also includes: a first adjustment unit, which is used to send a first control signal when the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device in the grid-connected state, wherein the first control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LCL filtering; a second adjustment unit, which is used to send a second control signal when the power consumption of the power-consuming device is greater than the power generation of the photovoltaic panel in the grid-connected state, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to the first L filtering; a third adjustment unit, which is used to send a second control signal when the power consumption of the power-consuming device is greater than the power consumption of the photovoltaic panel in the grid-connected state, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to the first L filtering; the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is less than the second threshold, and a third control signal is sent to adjust the filtering mode between the external power grid and the photovoltaic storage system to the second L filtering; the fourth adjustment unit is used to send the third control signal when the power generation of the photovoltaic panel is equal to the power consumption of the power consumer in the grid-connected state; the fifth adjustment unit is used to send the fourth control signal when the power generation of the photovoltaic panel is greater than the power consumption of the power consumer in the off-grid state, wherein the fourth control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LC filtering; the sixth adjustment unit is used to send the second control signal when the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is greater than the third threshold in the off-grid state; the seventh adjustment unit is used to send the third control signal when the difference between the power generation of the photovoltaic panel and the power consumption of the power consumer is less than the fourth threshold in the off-grid state.

[0052] Optionally, the filter inductance of the first L filter is greater than the filter inductance of the second L filter.

[0053] Figure 3 This is a control diagram of an embodiment of the present invention. The filtering mode is adjusted according to the working conditions of different operating modes. The control scheme of the present invention includes:

[0054] S31, collecting voltage and current signals of the AC power grid;

[0055] S32, off-grid and grid-connected status judgment;

[0056] S33, calculating the active power generated by the converter;

[0057] S34, determining the working state;

[0058] S35, selecting a filtering method;

[0059] S36, corresponding capacitor-inductor combination;

[0060] S37, select the corresponding switch to switch;

[0061] S38, determining whether the solar energy storage air conditioning system is operating normally;

[0062] S39, if it does not operate normally, terminate the entire system.

[0063] The following is a detailed explanation and description of the different operating modes according to the working conditions determined by S34:

[0064] Operation mode 1: Grid-connected. When connected to the mains, the solar-storage air-conditioning system generates the maximum power. After meeting the needs of air conditioning, it also supplies power to local loads and generates power to the grid. The large grid-connected current requires the best filtering circuit. Disconnect K1 and K2, close K3, and use the LCL topology. Figure 4 is a system topology diagram of an embodiment of the present invention in operation mode 1;

[0065] Operation mode 2: Grid-connected, with mains power, the power generation of the photovoltaic storage air conditioning system is minimal and cannot meet the needs of air conditioning. The grid provides most of the power to the photovoltaic storage air conditioning system. At this time, the current is large, but it is not in power generation mode. For power consumption mode, disconnect K1 and K3, close K2, and use a single L (large inductance). Figure 5 This is a system topology diagram of an embodiment of the present invention in operation mode 2;

[0066] Operation mode three: Grid-connected, with mains power, the solar-storage air-conditioning system generates a large amount of power, but it cannot meet the needs of air conditioning. The grid provides a small amount of power to the solar-storage air-conditioning system. At this time, the current is small, but it is not in power generation mode. For power consumption mode, disconnect K2 and K3, close K1, and use a single L (small inductance). Figure 6 This is a system topology diagram of an embodiment of the present invention in operation mode three;

[0067] Operation mode 4: Grid-connected, with mains power, the internal power generation of the solar-storage air-conditioning system meets the needs of air conditioning and is in an energy balance state. There is no power exchange between the grid and the solar-storage air-conditioning system. Without energy exchange, disconnect K2 and K3, close K1, and use a single L (small inductance). Figure 7 is a system topology diagram of an embodiment of the present invention in operation mode 4;

[0068] Operation mode 5: Off-grid, when disconnected from the mains, the solar-storage air-conditioning system generates the maximum power. After meeting the air-conditioning needs, the solar-storage air-conditioning system supplies power to the local load; disconnect K1, close K3 and K2, and use the LC type. Figure 8 This is a system topology diagram of an embodiment of the present invention in operation mode five;

[0069] Operation mode 6: Off-grid, when disconnected from the mains, the solar-storage air conditioning system generates minimal power and cannot meet the needs of air conditioning. Local power generation equipment provides most of the power to the solar-storage air conditioning system. At this time, the current is large, but it is not in power generation mode. For power consumption mode, disconnect K1 and K3, close K2, and use a single L (large inductance). Figure 9 is a system topology diagram of an embodiment of the present invention in operation mode six;

[0070] Operation mode seven: Off-grid, when disconnected from the mains, the photovoltaic storage air conditioning system generates a large amount of power, but it cannot meet the needs of air conditioning. The local power generation equipment provides a small part of the power to the photovoltaic storage air conditioning system. Disconnect K2 and K3, close K1, and use a single L (small inductance). Figure 10 This is a system topology diagram of an embodiment of the present invention in operation mode seven.

[0071] By adopting the solution of this embodiment, through unified detection and dispatch communication of the controller and relevant switching control, the filter circuit of the AC / DC converter connected to the grid of the photovoltaic storage air-conditioning system can be automatically adapted and adjusted under different working conditions of being on and off the grid, ensuring that the photovoltaic storage air-conditioning system is always in the optimal state.

[0072] This embodiment also provides a photovoltaic storage control system, which includes: a control circuit, including the circuit described in the above embodiment; a photovoltaic storage system, connected to the control circuit through an AC / DC converter, including photovoltaic panels and electrical equipment; a grid switch, connected between the control circuit and the AC mains, for controlling the access status of the AC mains.

[0073] Optionally, the external power grid also includes: local power generation equipment, which is connected to the photovoltaic storage system through the control circuit, and is used to power the photovoltaic storage system when it is off-grid and the power generation of the photovoltaic panel is less than the power consumption of the power-consuming equipment.

[0074] In this embodiment, a control method for a filtering circuit is also provided, and the process includes the following steps: collecting power supply information of an external power grid; determining the operating state of a photovoltaic storage system based on the power supply information, wherein the operating state is used to characterize the power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and electrical equipment; and adjusting the filtering mode between the external power grid and the photovoltaic storage system according to the operating state.

[0075] In one implementation of this embodiment, determining the operating status of the photovoltaic storage system based on the power supply information includes: determining the distribution network status of the photovoltaic storage system based on the power supply information, wherein the distribution network status includes: off-grid status or grid-connected status; calculating the active power emitted by the AC / DC converter of the photovoltaic storage system under the current distribution network status based on the power supply information; sending a control signal to the filtering circuit based on the distribution network status and the active power, wherein the control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system.

[0076] In one implementation of this embodiment, sending a control signal to the filtering circuit according to the distribution network status and the active power includes: in the grid-connected state, the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, sending a first control signal, wherein the first control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LCL filtering; in the grid-connected state, the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is greater than a first threshold, sending a second control signal, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to first L filtering; in the grid-connected state, the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is less than a second threshold, sending A third control signal is sent to adjust the filtering mode between the external power grid and the photovoltaic storage system to a second L filtering mode; in a grid-connected state, the power generation of the photovoltaic panel is equal to the power consumption of the power-consuming device, and the third control signal is sent; in an off-grid state, the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, and a fourth control signal is sent, wherein the fourth control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to an LC filtering mode; in an off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power-consuming device is greater than a third threshold, and the second control signal is sent; in an off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power-consuming device is less than a fourth threshold, and the third control signal is sent.

[0077] Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, or optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods of various embodiments of the present invention.

[0078] Example 2

[0079] An embodiment of the present invention further provides a storage medium storing a computer program, wherein the computer program is configured to execute the steps of any of the above method embodiments when running.

[0080] Optionally, in one aspect of this embodiment, the storage medium may be configured to store a computer program for performing the following steps:

[0081] S1, collects power supply information from the external power grid;

[0082] S2, determining an operating state of the photovoltaic storage system according to the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and power-consuming equipment;

[0083] S3: Adjust the filtering mode between the external power grid and the solar energy storage system according to the operating state.

[0084] Optionally, in this embodiment, the above-mentioned storage medium may include but is not limited to: a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and other media that can store computer programs.

[0085] An embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0086] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0087] Optionally, in one aspect of this embodiment, the processor may be configured to execute the following steps through a computer program:

[0088] S1, collects power supply information from the external power grid;

[0089] S2, determining an operating state of the photovoltaic storage system according to the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and power-consuming equipment;

[0090] S3: Adjust the filtering mode between the external power grid and the solar energy storage system according to the operating state.

[0091] Optionally, specific examples in this embodiment may refer to the examples described in the above embodiments and optional implementation modes, and this embodiment will not be described in detail here.

[0092] Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented using a general-purpose computing device, centralized on a single computing device, or distributed across a network of multiple computing devices. Alternatively, they can be implemented using program code executable by a computing device, which can then be stored in a storage device and executed by the computing device. In some cases, the steps shown or described can be performed in a different order than that shown, or can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0093] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A control circuit for a filter circuit, characterized in that: include: An acquisition circuit, connected to the external power grid, for acquiring power supply information of the external power grid; a controller connected to the acquisition circuit, and configured to determine an operating state of the photovoltaic storage system based on the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and electrical equipment; a filtering circuit connected between the controller and the AC / DC converter of the photovoltaic storage system, and configured to adjust a filtering mode between the external power grid and the photovoltaic storage system according to the operating state; The controller includes: an adjustment module, configured to send a control signal to the filter circuit according to a distribution network status of the photovoltaic storage system and the active power generated by the AC / DC converter, wherein the control signal is used to adjust a filtering mode between the external power grid and the photovoltaic storage system; The adjustment module also includes: a first adjustment unit, configured to, in a grid-connected state, send a first control signal when the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, wherein the first control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LCL filtering; a second adjustment unit, configured to, in a grid-connected state, send a second control signal when the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is greater than a first threshold, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to a first L filtering mode; a third adjustment unit, configured to, in a grid-connected state, send a third control signal for adjusting a filtering mode between the external grid and the photovoltaic storage system to a second L filtering mode when the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is less than a second threshold; a fourth adjustment unit, configured to send the third control signal when the power generation of the photovoltaic panel is equal to the power consumption of the power-consuming device in a grid-connected state; a fifth adjustment unit, configured to, in an off-grid state, send a fourth control signal when the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, wherein the fourth control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LC filtering; a sixth adjustment unit, configured to send the second control signal when, in an off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power-consuming device is greater than a third threshold; The seventh adjustment unit is configured to send the third control signal when, in an off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power-consuming device is less than a fourth threshold.

2. The circuit according to claim 1, characterized in that The controller includes: A determination module, configured to determine a network distribution state of the photovoltaic storage system according to the power supply information, wherein the network distribution state includes: an off-grid state or a grid-connected state; A calculation module is used to calculate the active power generated by the AC / DC converter in the current distribution network state according to the power supply information.

3. The circuit according to claim 1, wherein: The filter inductance of the first L filter is greater than the filter inductance of the second L filter.

4. The circuit according to claim 1, wherein: The filtering circuit comprises: a first inductor, a first port and the AC / DC converter; a second inductor, wherein the first port is connected to the second port of the first inductor, and the second port is connected to the external power grid; a first switch connected between two ports of the first inductor, and configured to control a connection state of the first inductor according to a control signal of the controller; a second switch connected between two ports of the second inductor, and configured to control a connection state of the second inductor according to a control signal of the controller; a first capacitor, a first port of which is grounded, and a second port of which is connected to a connection path between the second port of the first inductor and the first port of the second inductor via a third switch; The third switch is connected between the second port of the second inductor and the connection path, and is used to control the access state of the first capacitor according to the control signal of the controller.

5. The circuit according to claim 4, characterized in that The inductance of the first inductor is greater than the inductance of the second inductor.

6. The circuit according to claim 1, wherein: The filtering modes include: L filtering, LC filtering, and LCL filtering.

7. The circuit according to claim 1, wherein: The acquisition circuit includes: A first acquisition module, configured to acquire a voltage signal of the external power grid; The second acquisition module is used to acquire the current signal of the external power grid.

8. A solar storage control system, characterized in that: The system comprises: A control circuit comprising the control circuit of the filter circuit according to any one of claims 1 to 7; a photovoltaic storage system connected to the control circuit via an AC / DC converter, comprising photovoltaic panels and electrical equipment; The grid switch is connected between the control circuit and the AC mains grid and is used to control the access status of the AC mains grid.

9. The system according to claim 8, characterized in that The external power grid further comprises: The local power generation equipment is connected to the photovoltaic storage system through the control circuit, and is used to supply power to the photovoltaic storage system when it is off-grid and the power generation of the photovoltaic panel is less than the power consumption of the power-consuming equipment.

10. A control method for a filter circuit, applied to the control circuit of the filter circuit according to any one of claims 1 to 7, characterized in that: include: Collect power supply information from external power grid; Determining an operating state of the photovoltaic storage system according to the power supply information, wherein the operating state is used to characterize a power distribution state between the photovoltaic storage system and the external power grid, wherein the photovoltaic storage system includes photovoltaic panels and power-consuming equipment; The filtering mode between the external power grid and the photovoltaic storage system is adjusted according to the operating state.

11. The method according to claim 10, characterized in that Determining the operating status of the solar-storage system according to the power supply information includes: Determining a distribution network state of the photovoltaic storage system according to the power supply information, wherein the distribution network state includes: an off-grid state or a grid-connected state; Calculating the active power generated by the AC / DC converter of the solar storage system under the current distribution network state according to the power supply information; A control signal is sent to the filter circuit according to the distribution network status and the active power, wherein the control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system.

12. The method according to claim 11, characterized in that Sending a control signal to the filter circuit according to the distribution network state and the active power includes: In the grid-connected state, the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, and a first control signal is sent, wherein the first control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LCL filtering; In the grid-connected state, if the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is greater than a first threshold, a second control signal is sent, wherein the second control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to the first L filtering; In the grid-connected state, if the difference between the power consumption of the power-consuming device and the power generation of the photovoltaic panel is less than a second threshold, a third control signal is sent to adjust the filtering mode between the external power grid and the photovoltaic storage system to the second L filtering mode; In the grid-connected state, the power generation of the photovoltaic panel is equal to the power consumption of the power-consuming device, and the third control signal is sent; In an off-grid state, the power generation of the photovoltaic panel is greater than the power consumption of the power-consuming device, and a fourth control signal is sent, wherein the fourth control signal is used to adjust the filtering mode between the external power grid and the photovoltaic storage system to LC filtering; In an off-grid state, if the difference between the power generation of the photovoltaic panel and the power consumption of the power-consuming device is greater than a third threshold, the second control signal is sent; In an off-grid state, the difference between the power generation of the photovoltaic panel and the power consumption of the power-consuming device is less than a fourth threshold, and the third control signal is sent.

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