Power supply device and photovoltaic energy storage system

Abstract

The invention provides a power supply device and a photovoltaic energy storage system, and relates to the technical field of photovoltaic energy storage. The power supply device comprises a flyback transformer, a primary winding of the flyback transformer is connected with a high-voltage power supply module in the photovoltaic energy storage system, the primary winding of the flyback transformer is connected with an intermediate bus in the photovoltaic energy storage system, and a secondary winding of the flyback transformer is used for supplying power to a high-voltage side control unit; the input end of the step-down conversion module is connected with a low-voltage power supply module in the photovoltaic energy storage system, the enabling end of the step-down conversion module is connected with the high-voltage side control unit, the output end of the step-down conversion module is used for supplying power to the low-voltage side control unit, and the low-voltage side control unit is used for providing bus voltage for the intermediate bus. While the power supply stability of the low-voltage side control unit and the high-voltage side control unit is ensured, the occupied area of the power supply device on the circuit board and the hardware cost are reduced, and the power supply efficiency of the power supply device is also improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic energy storage technology, and in particular to a power supply device and a photovoltaic energy storage system. Background Art

[0002] With the growing global demand for renewable energy, photovoltaic power generation, as a clean and sustainable form of energy, is becoming increasingly popular, and photovoltaic energy storage systems are being used. Currently, many photovoltaic energy storage systems incorporate a power conversion system (PCS), which uses an auxiliary power supply to power the power control system.

[0003] like Figure 4 As shown, in the related art, multiple flyback transformers are provided in the auxiliary power supply to respectively power the control systems on the high-voltage side and the low-voltage side. There are problems that the circuit of the auxiliary power supply occupies a large board area and has high hardware cost. Summary of the Invention

[0004] The present application aims to solve the problems in the prior art or related art that the circuit of the auxiliary power supply occupies a large board area and has high hardware cost.

[0005] To this end, a first aspect of the present application provides a power supply device.

[0006] A second aspect of the present application provides a photovoltaic energy storage system.

[0007] In view of this, according to the first aspect of the present application, a power supply device is proposed, which is applied to a photovoltaic energy storage system. The photovoltaic energy storage system includes a power control module of an energy storage converter, the power control module includes a low-voltage side control unit and a high-voltage side control unit, and the power supply device is used to power the power control module. The power supply device includes: a flyback transformer, the primary winding of the flyback transformer is connected to the high-voltage power supply module in the photovoltaic energy storage system, the primary winding of the flyback transformer is connected to the intermediate bus in the photovoltaic energy storage system, and the secondary winding of the flyback transformer is used to power the high-voltage side control unit; a step-down conversion module, the input end of the step-down conversion module is connected to the low-voltage power supply module in the photovoltaic energy storage system, the enable end of the step-down conversion module is connected to the high-voltage side control unit, and the output end of the step-down conversion module is used to power the low-voltage side control unit, wherein the low-voltage side control unit is used to provide bus voltage to the intermediate bus.

[0008] In the technical solution of the present application, the power supply device supplies power to the low-voltage side control unit through a step-down conversion module and a transformer, and only one transformer needs to be set up. Therefore, while ensuring the power supply stability of the low-voltage side control unit and the high-voltage side control unit, the board area occupied by the power supply device and the hardware cost are reduced, and the power supply efficiency of the step-down circuit is higher, which also improves the power supply efficiency of the power supply device.

[0009] In some technical solutions, optionally, the low-voltage power supply module includes: a low-voltage photovoltaic panel and an energy storage battery, and the step-down conversion module includes: a first step-down circuit, the input end of the first step-down circuit is connected to the low-voltage photovoltaic panel, and the output end of the first step-down circuit is used to supply power to the low-voltage side control unit; a second step-down circuit, the input end of the second step-down circuit is connected to the energy storage battery, the input end of the second step-down circuit is connected to the high-voltage side control unit, and the output end of the second step-down circuit is used to supply power to the low-voltage side control unit.

[0010] In the technical solution of the present application, a first step-down circuit and a second step-down circuit are arranged in the step-down conversion module. When the low-voltage photovoltaic panel is used as the power source of the power supply device, the first step-down circuit can draw power from the low-voltage photovoltaic panel to power the low-voltage side control unit. When the energy storage battery is used as the power source of the power supply device, the second step-down circuit can draw power from the energy storage battery to power the low-voltage side control unit. Moreover, when the high-voltage power supply module is used as the power source of the power supply device, the second step-down circuit can also power the low-voltage side control unit in response to the enable signal of the high-voltage side control unit. There is no need to additionally set up a transformer in the power supply device to power the low-voltage side control unit. The low-voltage side control unit can be stably powered only by the step-down conversion module, which further reduces the board area and hardware cost of the power supply device.

[0011] In some technical solutions, optionally, the low-voltage side control unit includes: a battery management board, an energy management board, a processor of a DC-DC converter, and a low-voltage side processor, and the output end of the first step-down circuit and the output end of the second step-down circuit are both used to supply power to the battery management board and the energy management board; the step-down conversion module also includes: a first diode, the positive pole of the first diode is connected to the output end of the first step-down circuit and the output end of the second step-down circuit; a switching tube, the first end of the switching tube is connected to the negative pole of the first diode, the second end of the switching tube is connected to the processor of the DC-DC converter and the low-voltage side processor, and the control end of the switching tube is connected to the battery management board.

[0012] In the technical solution of the present application, by setting a first diode at the output end of the buck conversion module, the voltage reverse impact on the first buck circuit and the second buck circuit in the buck conversion module can be avoided, and a switch tube controlled by the battery management board is set between the first diode and the processor and low-voltage side processor of the DC-DC converter, so that the battery management board can control the on-off state of the switch tube, that is, when the low-voltage side control unit is on standby, the battery management board can actively turn off the switch tube, thereby cutting off the power supply of the buck conversion module to the low-voltage side control unit, further reducing the power consumption of the low-voltage side control unit when it is on standby.

[0013] In some technical solutions, optionally, the low-voltage side control unit also includes: a low-voltage side op amp, and the step-down conversion module also includes: a third step-down circuit, the input end of the third step-down circuit is connected to the second end of the switching tube, and the output end of the third step-down circuit is used to power the low-voltage side op amp.

[0014] In the technical solution of the present application, the low-voltage side control unit also includes a low-voltage side op amp, that is, an operational amplifier on the low-voltage side. Since the operating voltage of the low-voltage side op amp is lower than the operating voltage of other low-voltage side control units, a third step-down circuit is provided at the input end of the low-voltage side op amp to further step down the voltage of the electrical signal, thereby improving the stability of the power supply to the low-voltage side op amp.

[0015] In some technical solutions, optionally, the high-voltage power supply module includes: a high-voltage photovoltaic panel and an AC power supply, the output end of the high-voltage photovoltaic panel is used to supply power to the primary winding of the flyback transformer, and the power supply device also includes: a rectifier bridge module, the input end of the rectifier bridge module is connected to the AC power supply, and the output end of the rectifier bridge module is used to supply power to the primary winding of the flyback transformer.

[0016] In the technical solution of the present application, the high-voltage power supply module in the photovoltaic energy storage system includes an AC power supply and a high-voltage photovoltaic panel, and a rectifier bridge module is arranged between the AC power supply and the flyback transformer. The AC signal output by the AC power supply is rectified by the rectifier bridge module, so that the electrical signal transmitted to the flyback transformer is a DC signal, further improving the stability of the power supply to the high-voltage side control unit.

[0017] In some technical solutions, the high-voltage side control unit includes: a high-voltage side processor, a processor of a DC-AC converter, and a communication subunit, the communication subunit is a communication unit of the high-voltage side processor and the processor of the DC-AC converter, and the power supply device also includes: a second diode, the positive pole of the second diode is connected to the secondary winding of the flyback transformer, and the negative pole of the second diode is connected to the high-voltage side processor and the processor of the DC-AC converter; a fourth step-down circuit, the input end of the fourth step-down circuit is connected to the negative pole of the second diode, and the output end of the fourth step-down circuit is connected to the communication subunit.

[0018] In the technical solution of the present application, a second diode is provided at the secondary winding of the flyback transformer to prevent the reverse voltage from impacting the flyback transformer, and a fourth step-down circuit is provided on the input side of the communication sub-unit, and the voltage output by the secondary winding is further stepped down by the fourth step-down circuit, thereby improving the stability of power supply to the communication sub-unit.

[0019] In some technical solutions, optionally, the high-voltage side control unit includes: a high-voltage side op amp, and the power supply device also includes: a third diode, the positive pole of the third diode is connected to the secondary winding of the flyback transformer; a voltage stabilizing module, the input end of the voltage stabilizing module is connected to the negative pole of the third diode, and the output end of the voltage stabilizing module is used to power the high-voltage side op amp.

[0020] In the technical solution of the present application, the power supply device further includes a third diode, the anode of the third diode being connected to the second end of the secondary winding of the flyback transformer, the cathode of the third diode being connected to a voltage stabilizing module, the output of which being connected to a high-voltage-side operational amplifier (OPA), which is an operational amplifier on the high-voltage side. Because the operating voltage of the high-voltage-side OPA is relatively low, a voltage stabilizing module is provided at the input of the high-voltage-side OPA. The voltage stabilizing module stabilizes the electrical signal output from the secondary winding of the flyback transformer, thereby improving the stability of the power supply to the high-voltage-side OPA.

[0021] According to the second aspect of the present application, a battery management system is proposed, including: an energy storage inverter; a power control module connected to the energy storage inverter, the power control module being used to control the energy storage inverter; a power supply device in any of the above technical solutions, the power supply device being connected to the power control module, the power supply device being used to supply power to the power control module.

[0022] In the technical solution of the present application, the power supply device supplies power to the low-voltage side control unit through a step-down conversion module and a transformer, and only one transformer needs to be set up. Therefore, while ensuring the power supply stability of the low-voltage side control unit and the high-voltage side control unit, the board area occupied by the power supply device and the hardware cost are reduced, and the power supply efficiency of the step-down circuit is higher, which also improves the power supply efficiency of the power supply device.

[0023] In some technical solutions, the photovoltaic energy storage system also includes: an energy storage battery, a high-voltage photovoltaic panel and a low-voltage photovoltaic panel; the energy storage inverter includes: a DC-DC converter connected to the energy storage battery; a DC-AC converter connected to the DC-DC converter; a high-voltage power point tracking circuit connected between the high-voltage photovoltaic panel and the DC-AC converter; and a low-voltage power point tracking circuit connected between the low-voltage photovoltaic panel and the DC-DC converter.

[0024] In the technical solution of the present application, a DC-DC converter, a DC-AC converter, a high-voltage power point tracking circuit, and a low-voltage power point tracking circuit are provided in the energy storage inverter, so that the energy storage inverter can stably perform bidirectional conversion, power regulation, and system control on the photovoltaic energy storage system.

[0025] In some technical solutions, optionally, the photovoltaic energy storage system further includes: an anti-electromagnetic interference circuit connected to the DC-AC converter, the anti-electromagnetic interference circuit being used to perform anti-electromagnetic interference on the electrical signal output by the energy storage converter or the electrical signal input to the energy storage converter.

[0026] In the technical solution of the present application, an anti-electromagnetic interference circuit is provided in the photovoltaic energy storage system, and the anti-electromagnetic interference circuit is connected to the DC-AC converter, so as to perform anti-electromagnetic interference on the AC signal input to the DC-AC converter and the DC signal output by the DC-AC converter, thereby improving the anti-electromagnetic interference performance of the photovoltaic energy storage system.

[0027] Additional aspects and advantages of the present application will become apparent in the following description or may be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] Figure 1 One of the circuit topology diagrams of a power supply device provided in some embodiments of the present application is shown;

[0030] Figure 2 A second circuit topology diagram of a power supply device provided in some embodiments of the present application is shown;

[0031] Figure 3 shows a circuit topology diagram of a photovoltaic energy storage system provided in some embodiments of the present application;

[0032] Figure 4 A topological diagram of a power supply device in related art is shown.

[0033] The reference numerals are as follows:

[0034] 100 Power supply device, 110 Flyback transformer, 111 Primary winding, 112 Secondary winding, 120 Buck conversion module, 121 First buck circuit, 122 Second buck circuit, 123 First diode, 124 Switch tube, 125 Third buck circuit, 130 Intermediate bus, 140 Rectifier bridge module, 150 Second diode, 160 Fourth buck circuit, 170 Third diode, 180 Voltage regulator module, 200 Photovoltaic energy storage system, 210 Energy storage converter, 211 DC-DC converter, 212 DC-AC converter, 213 High voltage power point tracking circuit, 214 Low 220 power point tracking circuit, power control module, 221 low-voltage side control unit, 222 high-voltage side control unit, 223 low-voltage power supply module, 224 high-voltage power supply module, 225 low-voltage photovoltaic panel, 226 high-voltage photovoltaic panel, 227 energy storage battery, 228 AC power supply, 231 battery management board, 232 energy management board, 233 DC-DC converter processor, 234 low-voltage side processor, 235 low-voltage side operational amplifier, 236 high-voltage side processor, 237 communication subunit, 238 high-voltage side operational amplifier, 239 DC-AC converter processor, 240 anti-electromagnetic interference circuit. DETAILED DESCRIPTION

[0035] In order to more clearly understand the above-mentioned objectives, features and advantages of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the features of this embodiment and the embodiments can be combined with each other.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0037] Refer to the following Figures 1 to 3 A power supply device and a photovoltaic energy storage system according to some embodiments of the present application are described.

[0038] According to one embodiment of the present application, Figure 1 shows one of the circuit topology diagrams of a power supply device provided in some embodiments of the present application, Figure 2 FIG2 shows a second circuit topology diagram of a power supply device provided in some embodiments of the present application. Figure 3 The circuit topology diagram of the photovoltaic energy storage system provided in some embodiments of the present application is shown as follows: Figure 1 、 Figure 2 and Figure 3As shown, a power supply device 100 is proposed, which is applied to a photovoltaic energy storage system 200. The photovoltaic energy storage system 200 includes a power control module 220 of an energy storage converter 210. The power control module 220 includes a low-voltage side control unit 221 and a high-voltage side control unit 222. The power supply device 100 is used to supply power to the power control module 220. The power supply device 100 includes:

[0039] A flyback transformer 110, wherein the primary winding 111 of the flyback transformer 110 is connected to the high-voltage power supply module 224 in the photovoltaic energy storage system 200, the primary winding 111 of the flyback transformer 110 is connected to the intermediate bus 130 in the photovoltaic energy storage system 200, and the secondary winding 112 of the flyback transformer 110 is used to power the high-voltage side control unit 222; a step-down conversion module 120, wherein the input end of the step-down conversion module 120 is connected to the low-voltage power supply module 223 in the photovoltaic energy storage system 200, the enable end of the step-down conversion module 120 is connected to the high-voltage side control unit 222, and the output end of the step-down conversion module 120 is used to power the low-voltage side control unit 221, wherein the low-voltage side control unit 221 is used to provide a bus voltage to the intermediate bus 130.

[0040] In this embodiment, the power supply device 100 is an auxiliary power supply for the power control module 220 of the energy storage converter 210 in the photovoltaic energy storage system 200. When the energy storage converter 210 in the photovoltaic energy storage system 200 needs to work normally, the power supply device 100 serving as an auxiliary power supply needs to first be used to power the power control module 220 of the energy storage converter 210.

[0041] In this embodiment, the power control module 220 includes a low-voltage side control unit 221 and a high-voltage side control unit 222. The low-voltage side control unit 221 is used to control the low-voltage side devices in the photovoltaic energy storage system 200, and the high-voltage side control unit 222 is used to control the high-voltage side devices in the photovoltaic energy storage system 200.

[0042] like Figure 3As shown, the power control module 220 exemplarily includes: a low-voltage side MPPT DSP (Maximum Power Point Tracking Digital Signal Processor), a bidirectional isolated DC / DC DSP (DC / DC converter digital signal processor), a high-voltage side MPPT DSP, and a bidirectional isolated DC / AC DSP (DC / AC converter digital signal processor). The low-voltage side MPPT DSP and the bidirectional isolated DC / DC DSP constitute the low-voltage side control unit 221, and the high-voltage side MPPT DSP and the bidirectional isolated DC / AC DSP constitute the high-voltage side control unit 222. When the photovoltaic energy storage system 200 is operating, the power supply device 100, serving as an auxiliary power source, supplies power to the low-voltage side MPPT DSP, the bidirectional isolated DC / DC DSP, the high-voltage side MPPT DSP, and the bidirectional isolated DC / AC DSP. The low-voltage side MPPT DSP converts the unstable low-voltage MPPT (Maximum Power Point Tracking) input voltage into a stable voltage and then inputs it into the bidirectional isolated DC / DC DSP. The bidirectional isolated DC / DC DSP can also simultaneously receive the input voltage from the battery. The bidirectional isolated DC / DC DSP converts the input voltage to the voltage of the intermediate bus 130. The high-voltage MPPT DSP also converts the input high-voltage MPPT voltage to the high-voltage bus. The bidirectional isolated DC / AC DSP converts the input high-voltage bus voltage to AC voltage via a bidirectional isolated DC / AC converter, which is then fed into the grid or used to power a load. This process can also be reversed. The bidirectional isolated DC / AC DSP converts the input AC power to the high-voltage bus via a bidirectional isolated DC / AC converter. The bidirectional isolated DC / AC DSP converts the high-voltage bus voltage to battery voltage via a bidirectional isolated DC / AC converter for battery charging.

[0043] In this embodiment, the flyback transformer 110 includes a primary winding 111 and a secondary winding 112. The primary winding 111 is the input end of the flyback transformer 110, and the secondary winding 112 is the output end of the flyback transformer 110. That is, when the flyback transformer 110 supplies power to the high-voltage side control unit 222, the primary winding 111 of the flyback transformer 110 draws power from the high-voltage voltage module or the intermediate bus 130, reduces the obtained voltage, and outputs it to the high-voltage side control unit 222 through the secondary winding 112.

[0044] The step-down conversion module 120 includes at least one step-down circuit. The input of the step-down conversion module 120 is connected to the low-voltage power supply module 223. This means that the step-down conversion module 120 can draw power from the low-voltage power supply module 223 to power the low-voltage side control unit 221. The enable terminal of the step-down conversion module 120 is used to receive an enable signal. When the step-down conversion module 120 receives the enable signal, it can draw power from the low-voltage power supply module 223 to power the low-voltage side control unit 221 and the intermediate bus 130. The intermediate bus 130 serves as the hub for collecting and distributing electrical energy between the power generation side and the load / energy storage / grid-connected side. Its core function is to achieve efficient transmission and adaptation of electrical energy between different voltage levels and equipment modules.

[0045] Specifically, the photovoltaic energy storage system 200 includes power sources such as energy storage batteries, AC power supplies, high-voltage photovoltaic panels, and low-voltage photovoltaic panels. Among them, the energy storage batteries and low-voltage photovoltaic panels serve as the low-voltage power supply module 223, and the AC power supply and high-voltage photovoltaic panels serve as the high-voltage power supply module 224. Among them, the AC power supply can be municipal electricity.

[0046] The following describes the working state of the power supply when the power supply of the power supply device 100 is respectively the low-voltage power supply module 223 and the high-voltage power supply module 224:

[0047] When the low-voltage power supply module 223 supplies power, first, the step-down conversion module 120 supplies power to the low-voltage side control unit 221 and activates the bus voltage of the intermediate bus 130 of the power control module 220; then, the bus voltage of the intermediate bus 130 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate, and the secondary winding 112 of the flyback transformer 110 outputs electrical energy to power the high-voltage side control unit 222.

[0048] When the high-voltage power supply module 224 supplies power, first, the electric energy of the high-voltage power supply module 224 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate, and the secondary winding 112 of the flyback transformer 110 outputs electric energy to supply power to the high-voltage side control unit 222; then, after the high-voltage side control unit 222 is powered on, it transmits an enable signal to the buck conversion module 120, so that the buck conversion module 120 draws power from the low-voltage power supply module 223 to supply power to the low-voltage side control unit 221.

[0049] It should be noted that if Figure 4As shown, the auxiliary power supply provided in the energy storage converter in the related art includes two transformers, T1 and T2, and transformer T2 includes two secondary windings. The working principle of the auxiliary power supply in the related transformer technology is as follows: when powered by a battery or a low-voltage photovoltaic panel, the output power of transformer T1 activates transformer T2, and the output power of transformer T2 supplies power to the low-voltage MPPT DSP, bidirectional DC / DC DSP, high-voltage MPPT DSP, and bidirectional DC / AC DSP; the bidirectional DC / DC DSP and low-voltage MPPT DSP operate, activating the intermediate bus voltage of the power architecture; the intermediate bus voltage output of the power architecture maintains the operation of flyback transformer T2. When powered by a high-voltage photovoltaic panel or AC power, transformer T2 is directly driven to operate, and the output power of transformer T2 supplies power to the low-voltage MPPT DSP, bidirectional DC / DC DSP, high-voltage MPPT DSP, and bidirectional DC / AC DSP. It can be seen that two transformers T1 and T2 are set in the related art, so the circuit of the auxiliary power supply occupies a large board area and has high hardware cost. In addition, the transformer T2 includes two secondary windings, with a total of 4 outputs, resulting in insufficient voltage accuracy for each output and prone to voltage drift. For example, if the voltage is too high, it will cause overvoltage damage to the load circuit. Figure 1 and Figure 2 As shown, in the embodiment of the present application, only one flyback transformer 110 is required to be provided in the power supply device 100, and the flyback transformer 110 has only one secondary winding 112. The transformer T1 in the related art is replaced by the step-down conversion module 120, thereby reducing the hardware cost and the board area occupied by the power supply device 100. In addition, the flyback transformer 110 has a total of two outputs, the volume of the flyback transformer is further reduced, the design is simple, the voltage accuracy of each output is improved, the possibility of voltage drift is reduced, and the stability and power supply efficiency of the power supply device 100 as an auxiliary power supply are improved.

[0050] In an embodiment of the present application, the power supply device 100 supplies power to the low-voltage side control unit 221 through the step-down conversion module 120 and the transformer, and only one transformer needs to be provided. Therefore, while ensuring the power supply stability of the low-voltage side control unit 221 and the high-voltage side control unit 222, the board area occupied by the power supply device 100 and the hardware cost are reduced, and the power supply efficiency of the step-down circuit is higher, which also improves the power supply efficiency of the power supply device 100.

[0051] like Figure 1As shown, in some embodiments, optionally, the low-voltage power supply module 223 includes: a low-voltage photovoltaic panel and an energy storage battery, and the step-down conversion module 120 includes: a first step-down circuit 121, the input end of the first step-down circuit 121 is connected to the low-voltage photovoltaic panel, and the output end of the first step-down circuit 121 is used to supply power to the low-voltage side control unit 221; a second step-down circuit 122, the input end of the second step-down circuit 122 is connected to the energy storage battery, the input end of the second step-down circuit 122 is connected to the high-voltage side control unit 222, and the output end of the second step-down circuit 122 is used to supply power to the low-voltage side control unit 221.

[0052] In this embodiment, the low-voltage power supply module 223 includes a low-voltage photovoltaic panel and an energy storage battery. The low-voltage photovoltaic panel can convert light energy into electrical energy. The energy storage battery is used to store the electrical energy in the photovoltaic energy storage system 200. The energy storage battery can store the electrical energy converted from light energy by the photovoltaic panel, as well as the electrical energy converted from an AC power source to DC via a converter.

[0053] It should be noted that the first step-down circuit 121 and the second step-down circuit 122 are buck (step-down chopper) circuits.

[0054] Exemplarily, the voltage output by the low-voltage photovoltaic panel ranges from 17.5V to 120V.

[0055] In this embodiment, the step-down conversion module 120 includes a first step-down circuit 121 and a second step-down circuit 122. When different power sources in the photovoltaic energy storage system 200 serve as the power source for the power supply device 100, the low-voltage side control unit 221 is powered by the first step-down circuit 121 or the second step-down circuit 122, eliminating the need for an additional transformer in the power supply device 100 to power the low-voltage side control unit 221.

[0056] Specifically, when a low-voltage photovoltaic panel serves as the power source for the power supply device 100, the first step-down circuit 121 draws power from the low-voltage photovoltaic panel to supply power to the low-voltage side control unit 221. When a storage battery serves as the power source for the power supply device 100, the second step-down circuit 122 draws power from the storage battery to supply power to the low-voltage side control unit 221. When a high-voltage power supply module 224 serves as the power source for the power supply device 100, the flyback transformer 110 supplies power to the high-voltage side control unit 222, enabling the high-voltage side control unit 222 to transmit an enable signal to the enable terminal of the second step-down circuit 122. After receiving the enable signal, the second step-down circuit 122 draws power from the storage battery to supply power to the low-voltage side control unit 221.

[0057] In an embodiment of the present application, a first step-down circuit 121 and a second step-down circuit 122 are provided in the step-down conversion module 120. When the low-voltage photovoltaic panel serves as the power source of the power supply device 100, the first step-down circuit 121 can be used to draw power from the low-voltage photovoltaic panel to power the low-voltage side control unit 221. When the energy storage battery serves as the power source of the power supply device 100, the second step-down circuit 122 can be used to draw power from the energy storage battery to power the low-voltage side control unit 221. Moreover, when the high-voltage power supply module 224 serves as the power source of the power supply device 100, the second step-down circuit 122 can also power the low-voltage side control unit 221 in response to an enable signal of the high-voltage side control unit 222. There is no need to additionally provide a transformer in the power supply device 100 to power the low-voltage side control unit 221. The low-voltage side control unit 221 can be stably powered only by the step-down conversion module 120, thereby further reducing the board area and hardware cost of the power supply device 100.

[0058] like Figure 2 As shown, in some embodiments, optionally, the low-voltage side control unit 221 includes: a battery management board 231, an energy management board 232, a processor 233 of a DC-DC converter, and a low-voltage side processor 234. The output end of the first buck circuit 121 and the output end of the second buck circuit 122 are both used to supply power to the battery management board 231 and the energy management board 232;

[0059] The step-down conversion module 120 also includes: a first diode 123, the anode of the first diode 123 is connected to the output end of the first step-down circuit 121 and the output end of the second step-down circuit 122; a switch tube 124, the first end of the switch tube 124 is connected to the cathode of the first diode 123, the second end of the switch tube 124 is connected to the processor 233 and the low-voltage side processor 234 of the DC-DC converter, and the control end of the switch tube 124 is connected to the battery management board 231.

[0060] like Figure 1 As shown, the low-voltage side processor 234 in this application is a low-voltage side MPPT processor.

[0061] In this embodiment, the low-voltage side control unit 221 includes a battery management board 231, an energy management board 232, a DC / DC converter processor 233, and a low-voltage side processor 234. The battery management board 231 is a BMS (Battery Management System) board, which is used to monitor the voltage, current, temperature, and other parameters of the energy storage battery in real time, estimate the state of charge and health of the energy storage battery, ensure the safe operation of the energy storage battery, and perform battery balancing and safety protection. The energy management board 232 is an EMS (Energy Management System) board, which is used to receive data such as photovoltaic power generation, energy storage battery status, and grid demand, providing a basis for optimization strategies and formulating charge and discharge plans. The DC / DC converter processor 233 is a bidirectional isolated DC / DC DSP, which is used to control the operation of the bidirectional isolated DC / DC. The low-voltage side processor 234 is a low-voltage side MPPT DSP, which is used to perform maximum power point tracking.

[0062] In this embodiment, the positive pole of the first diode 123 is connected to the output end of the first buck circuit 121 and the second buck circuit 122, the negative pole of the first diode 123 is connected to the processor 233 and the low-voltage side processor 234 of the DC-DC converter through the switch tube 124, and the negative pole of the first diode 123 is connected to the battery management board 231 and the energy management board 232. The second diode 150 can avoid reverse voltage impact on the first buck circuit 121 and the second buck circuit 122, thereby improving the stability of the buck conversion module 120 supplying power to the low-voltage side control unit 221.

[0063] In this embodiment, the control end of the switch tube 124 is connected to the battery management board 231, that is, the battery management board 231 can control the on-off state of the switch tube 124. That is, when the low-voltage side control unit 221 is on standby, the battery management board 231 can actively turn off the switch tube 124, thereby cutting off the power supply of the step-down conversion module 120 to the low-voltage side control unit 221, further reducing the power consumption of the low-voltage side control unit 221 when it is on standby.

[0064] Exemplarily, the switch tube 124 remains in the on state when it does not receive the shutdown signal from the battery management board 231 .

[0065] Specifically, when the low-voltage photovoltaic panel is supplying power, the first step-down circuit 121 supplies power to the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state. The first step-down circuit 121 transmits the electric energy of the low-voltage photovoltaic panel to the processor 233 of the DC-DC converter and the low-voltage side processor 234 for power supply, and activates the bus voltage of the intermediate bus 130 of the power control module 220; then, the bus voltage of the intermediate bus 130 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to work, and the secondary winding 112 of the flyback transformer 110 outputs electric energy to power the high-voltage side control unit 222.

[0066] For example, the voltage output by the low-voltage photovoltaic panel is 17.5V to 120V. After being stepped down by the first step-down circuit 121, the electrical signal is 13V / 1.5A. The stepped-down electrical signal powers the battery management board 231, the energy management board 232, the processor 233 of the DC-DC converter, and the low-voltage side processor 234.

[0067] When the energy storage battery supplies power, the second step-down circuit 122 supplies power to the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state. The second step-down circuit 122 transmits the electric energy of the low-voltage photovoltaic panel to the processor 233 of the DC-DC converter and the low-voltage side processor 234 for power supply, and activates the bus voltage of the intermediate bus 130 of the power control module 220; then, the bus voltage of the intermediate bus 130 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate, and the secondary winding 112 of the flyback transformer 110 outputs electric energy to power the high-voltage side control unit 222.

[0068] When the high-voltage power supply module 224 supplies power, the electric energy of the high-voltage power supply module 224 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate, and the secondary winding 112 of the flyback transformer 110 outputs electric energy to power the high-voltage side control unit 222; then, after the high-voltage side control unit 222 is powered on, it transmits an enable signal to the second step-down circuit 122, so that the second step-down circuit 122 draws power from the energy storage battery to power the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state, and the first step-down circuit 121 transmits the electric energy of the low-voltage photovoltaic panel to the processor 233 of the DC-DC converter and the low-voltage side processor 234 for powering.

[0069] For example, the voltage output by the low-voltage photovoltaic panel is 24V to 60V. After being stepped down by the first step-down circuit 121, the electrical signal is 13V / 1.5A. The stepped-down electrical signal powers the battery management board 231, the energy management board 232, the processor 233 of the DC-DC converter, and the low-voltage side processor 234.

[0070] In the embodiment of the present application, by providing a first diode 123 at the output end of the buck conversion module 120, the voltage reverse impact of the first buck circuit 121 and the second buck circuit 122 in the buck conversion module 120 can be avoided, and a switch tube 124 controlled by the battery management board 231 is provided between the first diode 123 and the processor 233 of the DC-DC converter and the low-voltage side processor 234, so that the battery management board 231 can control the on-off state of the switch tube 124, that is, when the low-voltage side control unit 221 is on standby, the battery management board 231 can actively turn off the switch tube 124, thereby cutting off the power supply of the buck conversion module 120 to the low-voltage side control unit 221, further reducing the power consumption of the low-voltage side control unit 221 when on standby.

[0071] like Figure 2 As shown, in some embodiments, optionally, the low-voltage side control unit 221 also includes: a low-voltage side operational amplifier 235, and the buck conversion module 120 also includes: a third buck circuit 125, the input end of the third buck circuit 125 is connected to the second end of the switch tube 124, and the output end of the third buck circuit 125 is used to supply power to the low-voltage side operational amplifier 235.

[0072] In an embodiment of the present application, the low-voltage side control unit 221 also includes a low-voltage side op amp 235, that is, an operational amplifier on the low-voltage side. Since the operating voltage of the low-voltage side op amp 235 is lower than the operating voltage of other low-voltage side control units 221, a third step-down circuit 125 is set at the input end of the low-voltage side op amp 235 to further step down the voltage of the electrical signal, thereby improving the stability of the power supply to the low-voltage side op amp 235.

[0073] Illustratively, the electrical signal output by the first buck circuit 121 and the second buck circuit 122 is 13V / 1.5A, which is further stepped down by the third buck circuit 125 to obtain an electrical signal of -5V / 0.4A, and is transmitted to the low-voltage side operational amplifier 235 for power supply.

[0074] like Figure 2 As shown, in some embodiments, optionally, the high-voltage power supply module 224 includes: a high-voltage photovoltaic panel and an AC power supply, the output end of the high-voltage photovoltaic panel is used to supply power to the primary winding 111 of the flyback transformer 110, and the power supply device 100 also includes: a rectifier bridge module 140, the input end of the rectifier bridge module 140 is connected to the AC power supply, and the output end of the rectifier bridge module 140 is used to supply power to the primary winding 111 of the flyback transformer 110.

[0075] In this embodiment, the high-voltage power supply module 224 includes a high-voltage photovoltaic panel and an AC power supply. The high-voltage photovoltaic panel outputs a high-voltage DC signal, which can be directly transmitted to the primary winding 111 of the flyback transformer 110. The AC power supply outputs a high-voltage AC signal. Therefore, a rectifier bridge module 140 is connected to the primary winding 111 of the flyback transformer 110. The high-voltage AC signal output by the AC power supply is rectified by the rectifier bridge module 140 and then transmitted to the primary winding 111 of the flyback transformer 110.

[0076] For example, the voltage range of the electrical signal output by the high-voltage photovoltaic panel is 80V to 550V, and the electrical signal obtained after being stepped down by the flyback transformer 110 is 12V / 2.08A.

[0077] For example, the voltage range of the AC signal output by the AC power supply is 240V, the voltage range of the signal after rectification by the rectifier bridge is 271V to 407V, and the signal obtained after stepping down by the flyback transformer 110 is -8V / 0.25A.

[0078] In the embodiment of the present application, the high-voltage power supply module 224 in the photovoltaic energy storage system 200 includes an AC power supply and a high-voltage photovoltaic panel, and a rectifier bridge module 140 is provided between the AC power supply and the flyback transformer 110. The AC power signal output by the AC power supply is rectified by the rectifier bridge module 140 so that the electrical signals transmitted to the flyback transformer 110 are all DC signals, thereby further improving the stability of the power supply to the high-voltage side control unit 222.

[0079] like Figure 2 As shown, in some embodiments, the high-voltage side control unit 222 includes: a high-voltage side processor 236, a processor of a DC-AC converter and a communication subunit 237, the communication subunit 237 is a communication unit of the high-voltage side processor 236 and the processor of the DC-AC converter, and the power supply device 100 also includes: a second diode 150, the positive pole of the second diode 150 is connected to the secondary winding 112 of the flyback transformer 110, and the negative pole of the second diode 150 is connected to the high-voltage side processor 236 and the processor 239 of the DC-AC converter; a fourth step-down circuit 160, the input end of the fourth step-down circuit 160 is connected to the negative pole of the second diode 150, and the output end of the fourth step-down circuit 160 is connected to the communication subunit 237.

[0080] like Figure 1 As shown, the high-voltage side processor 236 in this application is a high-voltage side MPPT processor.

[0081] In this embodiment, high-side control unit 222 includes a high-side processor 236, a processor for the DC / AC converter, and a communication subunit 237 for communication between high-side processor 236 and the processor for the DC / AC converter. Specifically, DC / AC converter processor 239 is a bidirectional isolated DC / AC DSP, which controls the operation of the bidirectional isolated DC / AC. High-side processor 236 is a high-side MPPT DSP, which performs maximum power point tracking.

[0082] In this embodiment, a second diode 150 is provided between the secondary winding 112 of the flyback transformer 110 and the high-voltage side processor 236 and the processor of the DC-AC converter, which can prevent the reverse voltage from impacting the secondary winding 112 of the flyback transformer 110, thereby improving the power supply stability of the flyback transformer 110 to the high-voltage side processor 236, the DC-AC converter processing and the communication sub-unit 237.

[0083] Illustratively, the electrical signal outputted from the first end of the secondary winding 112 of the flyback transformer 110 is 12V / 2.08A, which is directly transmitted to the high-voltage side processor 236 and the processor of the DC-AC converter for power supply.

[0084] In this embodiment, a fourth step-down circuit 160 is provided between the cathode of the second diode 150 and the communication sub-unit 237. Since the operating voltage of the communication sub-unit 237 is relatively low, the fourth step-down circuit 160 further steps down the voltage of the electrical signal output from the first end of the secondary winding 112 of the flyback transformer 110, thereby improving the stability of the power supply to the communication sub-unit 237.

[0085] Illustratively, the electrical signal outputted from the first end of the secondary winding 112 of the flyback transformer 110 is 12V / 2.08A, and the battery cell after being stepped down by the fourth step-down circuit 160 is 5V / 0.4A, thereby powering the communication sub-unit 237 .

[0086] In an embodiment of the present application, a second diode 150 is provided in the secondary winding 112 of the flyback transformer 110 to prevent the reverse voltage from causing an impact on the flyback transformer 110, and a fourth step-down circuit 160 is provided on the input side of the communication sub-unit 237. The voltage output by the secondary winding 112 is further stepped down by the fourth step-down circuit 160, thereby improving the stability of power supply to the communication sub-unit 237.

[0087] like Figure 2As shown, in some embodiments, optionally, the high-voltage side control unit 222 includes: a high-voltage side operational amplifier 238, and the power supply device 100 also includes: a third diode 170, the positive electrode of the third diode 170 is connected to the secondary winding 112 of the flyback transformer 110; a voltage regulator module 180, the input end of the voltage regulator module 180 is connected to the negative electrode of the third diode 170, and the output end of the voltage regulator module 180 is used to power the high-voltage side operational amplifier 238.

[0088] In the embodiment of the present application, the power supply device 100 further includes a third diode 170. The anode of the third diode 170 is connected to the second end of the secondary winding 112 of the flyback transformer 110. The cathode of the third diode 170 is connected to a voltage stabilizing module 180. The output of the voltage stabilizing module 180 is connected to a high-voltage side operational amplifier 238. The high-voltage side operational amplifier 238 is a high-voltage side operational amplifier. Because the operating voltage of the high-voltage side operational amplifier 238 is relatively low, the voltage stabilizing module 180 is provided at the input of the high-voltage side operational amplifier 238. The voltage stabilizing module 180 stabilizes the electrical signal output from the secondary winding 112 of the flyback transformer 110, thereby improving the stability of the power supply to the high-voltage side operational amplifier 238.

[0089] Exemplarily, the voltage stabilizing module 180 is an LDO (Low Dropout Regulator) circuit.

[0090] For example, the electrical signal outputted from the second end of the secondary winding 112 of the flyback transformer 110 is -8V / 0.25A, and the electrical signal after being stabilized by the voltage stabilizing module 180 is -5V / 0.4A, which is transmitted to the high-voltage side operational amplifier 238 for power supply.

[0091] The following describes the working process of the power supply device 100 in different power supply working modes:

[0092] Energy storage battery power supply mode:

[0093] When the energy storage battery supplies power, the second step-down circuit 122 supplies power to the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state. The second step-down circuit 122 transmits the electric energy of the low-voltage photovoltaic panel to the processor 233 and the low-voltage side processor 234 of the DC-DC converter for power supply, and activates the bus voltage of the intermediate bus 130 of the power control module 220. Then, the bus voltage of the intermediate bus 130 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate. The secondary winding 112 of the flyback transformer 110 outputs electric energy to the high-voltage side processor 236 and the DC-AC converter for processing. At this time, the entire energy storage converter 210 is in operation.

[0094] Low-voltage photovoltaic panel power supply mode:

[0095] When the low-voltage photovoltaic panel is supplying power, the first step-down circuit 121 supplies power to the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state. The first step-down circuit 121 transmits the power of the low-voltage photovoltaic panel to the processor 233 of the DC-DC converter and the low-voltage side processor 234 for power supply, and activates the bus voltage of the intermediate bus 130 of the power control module 220. Then, the bus voltage of the intermediate bus 130 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate. The secondary winding 112 of the flyback transformer 110 outputs power to the high-voltage side processor 236 and the DC-AC converter for processing. At this time, the entire energy storage converter 210 is in operation.

[0096] High-voltage photovoltaic panel power supply mode:

[0097] The electric energy of the high-voltage power supply module 224 is transmitted to the primary winding 111 of the flyback transformer 110, activating the flyback transformer 110 to operate. The secondary winding 112 of the flyback transformer 110 outputs electric energy to the high-voltage side processor 236 and the DC-AC converter for processing. Then, after the high-voltage side control unit 222 is powered on, it transmits an enable signal to the second buck circuit 122, so that the second buck circuit 122 draws power from the energy storage battery to power the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state, and the first buck circuit 121 transmits the electric energy of the low-voltage photovoltaic panel to the processor 233 of the DC-DC converter and the low-voltage side processor 234 for powering. At this time, the entire energy storage converter 210 is in operation.

[0098] AC power supply mode:

[0099] The electric energy of the AC power supply is transmitted to the primary winding 111 of the flyback transformer 110 through the rectifier bridge module 140, activating the flyback transformer 110 to work, and the secondary winding 112 of the flyback transformer 110 outputs electric energy to the high-voltage side processor 236 and the DC-AC converter for processing; then, after the high-voltage side control unit 222 is powered on, it transmits an enable signal to the second buck circuit 122, so that the second buck circuit 122 draws power from the energy storage battery to power the battery management board 231 and the energy management board 232. The battery management board 231 controls the switch tube 124 to be in the on state, and the first buck circuit 121 transmits the electric energy of the low-voltage photovoltaic panel to the processor 233 of the DC-DC converter and the low-voltage side processor 234 for powering. At this time, the entire energy storage converter 210 is in operation.

[0100] According to one embodiment of the present application, a battery management system is provided, such as Figure 3As shown, the battery management system includes: an energy storage converter 210; a power control module 220 connected to the energy storage converter 210 and configured to control the energy storage converter 210; and the power supply device 100 in any of the above embodiments, the power supply device 100 being connected to the power control module 220 and configured to supply power to the power control module 220. Therefore, all the beneficial technical effects of the power supply device 100 in any of the above embodiments are achieved, and no further details will be given here.

[0101] In this embodiment, the power supply device 100 is an auxiliary power supply for the power control module 220 of the energy storage converter 210 in the photovoltaic energy storage system 200. When the energy storage converter 210 in the photovoltaic energy storage system 200 needs to work normally, the power supply device 100 serving as an auxiliary power supply needs to first be used to power the power control module 220 of the energy storage converter 210.

[0102] In an embodiment of the present application, the power supply device 100 supplies power to the low-voltage side control unit 221 through the step-down conversion module 120 and the transformer, and only one transformer needs to be provided. Therefore, while ensuring the power supply stability of the low-voltage side control unit 221 and the high-voltage side control unit 222, the board area occupied by the power supply device 100 and the hardware cost are reduced, and the power supply efficiency of the step-down circuit is higher, which also improves the power supply efficiency of the power supply device 100.

[0103] like Figure 3 As shown, in some embodiments, the photovoltaic energy storage system 200 further includes: an energy storage battery 227, a high-voltage photovoltaic panel 226 and a low-voltage photovoltaic panel 225; the energy storage converter includes: a DC-DC converter 211 connected to the energy storage battery 227; a DC-AC converter 212 connected to the DC-DC converter 211; a high-voltage power point tracking circuit 213 connected between the high-voltage photovoltaic panel 226 and the DC-AC converter 212; and a low-voltage power point tracking circuit 214 connected between the low-voltage photovoltaic panel 225 and the DC-DC converter 211.

[0104] In this embodiment, the DC-DC converter 211 is a bidirectional isolated DC / DC converter, which is controlled by a bidirectional isolated DC / DC DSP, i.e., the processor of the DC-DC converter. The DC-AC converter 212 is a bidirectional isolated DC / AC converter, which is controlled by a bidirectional isolated DC / AC DSP, i.e., the processor of the DC-AC converter. The high-voltage power point tracking circuit 213 is a high-side MPPT (Maximum Power Point Tracking) circuit, which is controlled by a high-side MPPT DSP, i.e., the high-side processor. The low-voltage power point tracking circuit 214 is a low-side MPPT circuit, which is controlled by a low-voltage MPPT DSP, i.e., the low-voltage side processor.

[0105] In the embodiment of the present application, a DC-DC converter 211, a DC-AC converter 212, a high-voltage power point tracking circuit 213, and a low-voltage power point tracking circuit 214 are provided in the energy storage converter, so that the energy storage converter can stably perform bidirectional conversion, power regulation, and system control on the photovoltaic energy storage system 200.

[0106] like Figure 3 As shown, in some embodiments, optionally, the photovoltaic energy storage system 200 further includes: an anti-electromagnetic interference circuit 240, connected to the DC-AC converter 212, and the anti-electromagnetic interference circuit 240 is used to perform anti-electromagnetic interference on the electrical signal output by the energy storage converter or the electrical signal input to the energy storage converter.

[0107] In the embodiment of the present application, an anti-electromagnetic interference circuit 240 is provided in the photovoltaic energy storage system 200. The anti-electromagnetic interference circuit 240 is connected to the DC-AC converter 212, thereby performing anti-electromagnetic interference on the AC signal input to the DC-AC converter and the DC signal output by the DC-AC converter 212, thereby improving the anti-electromagnetic interference performance of the photovoltaic energy storage system 200.

[0108] Exemplarily, the photovoltaic energy storage system 200 includes an off-grid port, a grid port, a diesel-electric port, and a car charger port. The anti-electromagnetic interference circuit 240 is arranged between the DC-AC converter 212 and the off-grid port, the grid port, the diesel-electric port, and the car charger port, and the anti-electromagnetic interference circuit 240 includes two-stage circuits, namely the first-stage EMI (Electromagnetic Interference) and the second-stage EMI.

[0109] It should be clarified that in the claims, specification and drawings of this application, the term "plurality" refers to two or more. Unless otherwise clearly defined, the orientation or positional relationship indicated by the terms "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the purpose of more conveniently describing this application and making the description process simpler, and is not intended to indicate or imply that the device or element referred to must have the specific orientation described, be constructed and operated in a specific orientation. Therefore, these descriptions cannot be understood as limitations on this application. The terms "connect", "install", "fix" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection between multiple objects, or a detachable connection between multiple objects, or an integral connection; it can be a direct connection between multiple objects, or an indirect connection between multiple objects through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood based on the specific circumstances of the above data.

[0110] In the claims, specification, and drawings of this application, the terms "one embodiment," "some embodiments," "a specific embodiment," and the like mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of this application. In the claims, specification, and drawings of this application, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0111] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A power supply device, characterized in that: Applied to a photovoltaic energy storage system, the photovoltaic energy storage system includes a power control module of an energy storage converter, the power control module includes a low-voltage side control unit and a high-voltage side control unit, the power supply device is used to power the power control module, and the power supply device includes: A flyback transformer, wherein the primary winding of the flyback transformer is connected to the high-voltage power supply module in the photovoltaic energy storage system, the primary winding of the flyback transformer is connected to the intermediate bus in the photovoltaic energy storage system, and the secondary winding of the flyback transformer is used to power the high-voltage side control unit; A step-down conversion module, wherein the input end of the step-down conversion module is connected to the low-voltage power supply module in the photovoltaic energy storage system, the enable end of the step-down conversion module is connected to the high-voltage side control unit, and the output end of the step-down conversion module is used to power the low-voltage side control unit, wherein the low-voltage side control unit is used to provide a bus voltage to the intermediate bus.

2. The power supply device according to claim 1, characterized in that: The low-voltage power supply module includes: a low-voltage photovoltaic panel and an energy storage battery, and the step-down conversion module includes: a first step-down circuit, wherein an input end of the first step-down circuit is connected to the low-voltage photovoltaic panel, and an output end of the first step-down circuit is used to supply power to the low-voltage side control unit; a second step-down circuit, wherein the input end of the second step-down circuit is connected to the energy storage battery, the enable end of the second step-down circuit is connected to the high-voltage side control unit, and the output end of the second step-down circuit is used to supply power to the low-voltage side control unit.

3. The power supply device according to claim 2, characterized in that: The low-voltage side control unit includes: a battery management board, an energy management board, a processor of a DC-DC converter and a low-voltage side processor, and the output end of the first buck circuit and the output end of the second buck circuit are both used to supply power to the battery management board and the energy management board; The step-down conversion module further includes: a first diode, wherein an anode of the first diode is connected to an output end of the first step-down circuit and an output end of the second step-down circuit; A switching tube, wherein a first end of the switching tube is connected to the cathode of the first diode, a second end of the switching tube is connected to the processor of the DC-DC converter and the low-voltage side processor, and a control end of the switching tube is connected to the battery management board.

4. The power supply device according to claim 3, characterized in that: The low-voltage side control unit further includes: a low-voltage side operational amplifier, and the step-down conversion module further includes: A third step-down circuit, wherein the input end of the third step-down circuit is connected to the second end of the switch tube, and the output end of the third step-down circuit is used to supply power to the low-voltage side operational amplifier.

5. The power supply device according to any one of claims 1 to 4, characterized in that: The high-voltage power supply module includes: a high-voltage photovoltaic panel and an AC power supply. The output end of the high-voltage photovoltaic panel is used to supply power to the primary winding of the flyback transformer. The power supply device also includes: A rectifier bridge module, wherein the input end of the rectifier bridge module is connected to the AC power supply, and the output end of the rectifier bridge module is used to supply power to the primary winding of the flyback transformer.

6. The power supply device according to any one of claims 1 to 4, characterized in that: The high-voltage side control unit includes: a high-voltage side processor, a processor of the DC / AC converter, and a communication subunit, wherein the communication subunit is a communication unit between the high-voltage side processor and the processor of the DC / AC converter. The power supply device also includes: a second diode, wherein an anode of the second diode is connected to the secondary winding of the flyback transformer, and a cathode of the second diode is connected to the high-voltage side processor and the processor of the DC-AC converter; A fourth step-down circuit, wherein an input end of the fourth step-down circuit is connected to the cathode of the second diode, and an output end of the fourth step-down circuit is connected to the communication sub-unit.

7. The power supply device according to any one of claims 1 to 4, characterized in that: The high-voltage side control unit includes: a high-voltage side operational amplifier, and the power supply device also includes: a third diode, wherein an anode of the third diode is connected to a secondary winding of the flyback transformer; A voltage stabilizing module, wherein the input end of the voltage stabilizing module is connected to the cathode of the third diode, and the output end of the voltage stabilizing module is used to power the high-voltage side operational amplifier.

8. A photovoltaic energy storage system, characterized in that: include: Energy storage converter; A power control module is connected to the energy storage converter, and is used to control the energy storage converter; The power supply device according to any one of claims 1 to 7, wherein the power supply device is connected to the power control module, and the power supply device is used to supply power to the power control module.

9. The photovoltaic energy storage system according to claim 8, characterized in that: The photovoltaic energy storage system further comprises: an energy storage battery, a high-voltage photovoltaic panel and a low-voltage photovoltaic panel; The energy storage converter comprises: a DC-DC converter connected to the energy storage battery; a DC-AC converter, connected to the DC-DC converter; a high-voltage power point tracking circuit, connected between the high-voltage photovoltaic panel and the DC-AC converter; A low-voltage power point tracking circuit is connected between the low-voltage photovoltaic panel and the DC-DC converter.

10. The photovoltaic energy storage system according to claim 9, characterized in that: Also includes: An anti-electromagnetic interference circuit is connected to the DC-AC converter, and is used to perform anti-electromagnetic interference on the electrical signal output by the energy storage converter or the electrical signal input to the energy storage converter.

Images