Power supply system

Abstract

A power supply system. The power supply system comprises at least one power supply unit, the power supply unit comprises a DC power supply, an energy storage circuit, an energy storage device, a boost circuit and a DC / AC conversion device, the input end of the energy storage circuit is coupled with the DC power supply, the output end of the energy storage circuit is coupled with the energy storage device, and the boost circuit is coupled with the DC / AC conversion device. The storage device is suitable for storing direct current output by the direct current power supply to the energy storage device; the input end of the booster circuit is coupled with the energy storage device, the output end of the booster circuit is coupled with the DC / AC conversion device, and the booster circuit is suitable for boosting the direct current signal output by the energy storage device; the input end of the DC / AC conversion device is coupled with the booster circuit, the output end of the DC / AC conversion device is coupled with an alternating current power grid, and the DC / AC conversion device is suitable for inverting the boosted direct current signal to obtain an alternating current signal suitable for being input into the alternating current power grid and outputting the alternating current signal to the alternating current power grid. By adopting the scheme, diversified power supply requirements of users can be met.

Description

Technical Field

[0001] This utility model relates to the field of power supply technology, specifically to a power supply system. Background Technology

[0002] A DC / AC converter is a power conversion device that inverts direct current into alternating current.

[0003] DC / AC converters have a wide range of applications, from traditional motor drives and uninterruptible power supplies (UPS) to new energy fields such as photovoltaic power generation, wind power generation, and fuel cell power generation. A DC / AC converter can convert the direct current (DC) output from a DC power source into alternating current (AC) that the electrical equipment can use.

[0004] When using DC / AC converters to power electrical equipment, the DC power output from the DC power supply is usually directly input into the AC power grid, which is difficult to meet diverse power supply needs. Utility Model Content

[0005] The problem this invention aims to solve is: how to input DC power from a DC power supply into an AC power grid to meet diverse power supply needs.

[0006] To address the aforementioned problems, this utility model provides a power supply system comprising: at least one power supply unit, wherein the power supply unit includes: a DC power supply, an energy storage circuit, an energy storage device, a boost circuit, and a DC / AC converter, wherein:

[0007] The energy storage circuit has an input terminal coupled to the DC power supply and an output terminal coupled to the energy storage device, and is adapted to store the DC power output by the DC power supply into the energy storage device.

[0008] The boost circuit has its input terminal coupled to the energy storage device and its output terminal coupled to the DC / AC converter, and is suitable for boosting the DC signal output by the energy storage device.

[0009] The DC / AC converter has its input terminal coupled to the boost circuit and its output terminal coupled to the AC power grid. It is suitable for inverting the boosted DC signal to obtain an AC signal suitable for input to the AC power grid and output to the AC power grid.

[0010] Optionally, the energy storage circuit includes:

[0011] The first capacitor is connected in parallel with the DC power supply;

[0012] A first energy storage inductor, wherein a first terminal of the first energy storage inductor is connected to a first terminal of the first capacitor;

[0013] A first switching transistor, wherein a first terminal of the first switching transistor is connected to a second terminal of the first energy storage inductor, and a second terminal of the first switching transistor is connected to a second terminal of the first capacitor;

[0014] The second switching transistor has a first terminal connected to the second terminal of the first energy storage inductor and the first terminal of the first switching transistor, and the second terminal of the second switching transistor is connected to the second capacitor.

[0015] And the second capacitor, which is connected in parallel with the energy storage device.

[0016] Optionally, the boost circuit includes:

[0017] The first boost sub-circuit is connected to the second terminal of the second switching transistor;

[0018] The second boost sub-circuit is connected in parallel with the first boost sub-circuit.

[0019] And a third capacitor, which is connected in parallel with the first boost sub-circuit and the second boost sub-circuit;

[0020] The first boost sub-circuit and the second boost sub-circuit operate alternately.

[0021] Optionally, the energy storage circuit includes:

[0022] The first capacitor is connected in parallel with the DC power supply;

[0023] First energy storage inductor; the first terminal of the first energy storage inductor is connected to the first terminal of the first capacitor;

[0024] First switching transistor; the first end of the first switching transistor is connected to the second end of the first energy storage inductor, and the second end of the first switching transistor is connected to the second end of the first capacitor;

[0025] And a second switching transistor; the first end of the second switching transistor is connected to the second end of the first energy storage inductor and the first end of the first switching transistor; the second end of the second switching transistor is connected to the energy storage device.

[0026] Optionally, the boost circuit includes:

[0027] The fourth capacitor is connected to the second terminal of the second switching transistor and the second terminal of the first switching transistor;

[0028] The first boost circuit is connected in parallel with the fourth capacitor;

[0029] The second boost circuit is connected in parallel with the fourth capacitor;

[0030] And a third capacitor, which is connected in parallel with the first boost sub-circuit and the second boost sub-circuit;

[0031] The first boost sub-circuit and the second boost sub-circuit operate alternately.

[0032] Optionally, the first boost sub-circuit has the same structure as the second boost sub-circuit.

[0033] Optionally, the first boost sub-circuit includes:

[0034] First transformer;

[0035] The third switching transistor is located on the primary side of the first transformer;

[0036] The first diode is located on the secondary side of the first transformer.

[0037] Optionally, the energy storage device includes a rechargeable battery.

[0038] Optionally, the energy storage device further includes a switching circuit connected to the rechargeable battery.

[0039] Optionally, the DC power source is a photovoltaic panel.

[0040] Optionally, it includes two or more power supply units, which are connected in parallel and share the same energy storage device and the same DC / AC converter.

[0041] Optionally, the power supply system further includes a controller adapted to control the operation of the power supply system.

[0042] Compared with the prior art, the technical solution of this utility model embodiment has the following advantages:

[0043] By applying the solution of this utility model, an energy storage circuit and a boost circuit are set up. The energy storage circuit can store the DC power output from the DC power source into the energy storage device, and the boost circuit can boost the DC power signal output from the energy storage device. Thus, the energy storage device can store the DC power output from the DC power source as needed and then provide it to the AC power grid, thereby better meeting diverse power supply needs. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the structure of a power supply system according to an embodiment of the present utility model;

[0045] Figure 2 This is a schematic diagram of the circuit structure of a power supply system according to an embodiment of the present utility model;

[0046] Figure 3 This is a schematic diagram of another power supply system in an embodiment of this utility model;

[0047] Figure 4 This is a schematic diagram of the circuit structure of another power supply system in an embodiment of this utility model. Detailed Implementation

[0048] When using a DC / AC converter to power electrical equipment, the input terminal of the DC / AC converter is connected to a DC power source, and the output terminal is connected to an AC power grid, thereby directly inputting the DC power output from the DC power source into the AC power grid.

[0049] However, the above-mentioned solution is insufficient to meet the diverse power supply needs of users.

[0050] To address this problem, this utility model provides a power supply system, which includes an energy storage circuit and a boost circuit. The energy storage circuit stores the DC power output from the DC power source into an energy storage device, and the boost circuit boosts the DC power output from the energy storage device. Thus, the energy storage device can store the DC power output from the DC power source as needed and then supply it to the AC power grid, better meeting diverse power supply demands.

[0051] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0052] This utility model embodiment provides a power supply system, the power supply system including at least one power supply unit, as shown in the following figure. Figure 1 The power supply unit may include: a DC power supply 11, an energy storage circuit 12, an energy storage device 13, a discharge circuit 14, and a DC / AC converter 15.

[0053] The energy storage circuit 12 has its input terminal coupled to the DC power supply 11 and its output terminal coupled to the energy storage device 13, and is adapted to store the DC power output by the DC power supply 11 into the energy storage device 13.

[0054] The boost circuit 14 has its input terminal coupled to the energy storage device 13 and its output terminal coupled to the DC / AC converter 15, and is adapted to boost the DC signal output by the energy storage device 12.

[0055] The DC / AC converter 15 has its input terminal coupled to the boost circuit 14 and its output terminal coupled to the AC power grid. It is adapted to invert the DC signal output by the energy storage device 13 to obtain an AC signal suitable for input to the AC power grid and output to the AC power grid.

[0056] The DC power output from the DC power supply 11 can be stored in the energy storage device 13 through the energy storage circuit 12, and the output of the energy storage device 13 can be discharged through the boost circuit 14, thereby better meeting diverse power supply needs.

[0057] It should be noted that the "coupling" described in the embodiments of this utility model refers to a direct or indirect connection. For example, A and B can be coupled, either directly or indirectly through one or more other electrical components. For instance, A can be directly connected to C, and C can be directly connected to B, thus achieving coupling between A and B through C.

[0058] In specific implementations, the DC power supply 11 can be an energy storage battery (such as a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-ion battery, a lithium polymer battery, etc.), a photovoltaic panel, or some converters (such as an AC / DC converter or a DC / DC converter). There are no restrictions here, as long as it can provide DC power.

[0059] In specific implementations, the energy storage circuit 12 can have various circuit structures, which are not limited here, as long as it can store the DC power output from the DC power supply 11 into the energy storage device 13.

[0060] In one embodiment, reference is made to Figure 2 The energy storage circuit 12 may include:

[0061] The first capacitor C1 is connected in parallel with the DC power supply 11;

[0062] The first energy storage inductor L1, the first end of the first energy storage inductor L1 is connected to the first end of the first capacitor C1;

[0063] The first switch transistor M1 has its first end connected to the second end of the first energy storage inductor L1, and its second end connected to the second end of the first capacitor C1.

[0064] The second switch M2 has its first end connected to the second end of the first energy storage inductor L1 and the first end of the first switch M1, and its second end connected to the second capacitor C2.

[0065] And a second capacitor C2, which is connected in parallel with the energy storage device 13.

[0066] In practical implementation, the first capacitor C1 can filter the DC signal output by the DC power supply 11, removing ripple current. Ripple current refers to the high-frequency component of the DC signal output by the DC power supply 11. Ripple current can cause changes in current or voltage amplitude, potentially leading to breakdown of other devices. Therefore, using the first capacitor C1 to filter ripple current can improve the reliability of the power supply system.

[0067] In specific implementation, when the first switch M1 is turned on and the second switch M2 is turned off, the DC signal filtered by the first capacitor C1 charges the first energy storage inductor L1, and the first energy storage inductor L1 stores the DC power output from the DC power supply 11.

[0068] When the first switch M1 is off and the second switch M2 is on, since the first energy storage inductor L1 already stores DC current, the DC signal output by the DC power supply 11 can be output to the second capacitor C2 and the energy storage device 13 via the first energy storage inductor L1, thereby charging the second capacitor C2 and the energy storage device 13. Furthermore, the second capacitor C2, connected in parallel across the energy storage device 13, can also filter the DC signal output by the DC power supply 11, removing ripple current.

[0069] In practical implementation, by controlling the switching frequencies of the first switch M1 and the second switch M2, the output of the energy storage circuit 12 is made more stable. By controlling the switching durations of the first switch M1 and the second switch M2, the amount of electrical energy stored in the energy storage device 13 can be adjusted.

[0070] In specific implementations, the first switch M1 and the second switch M2 can be metal-oxide-semiconductor field-effect transistors (MOSFETs) or other semiconductor devices such as insulated-gate bipolar transistors (IGBTs). When the first switch M1 and the second switch M2 are MOSFETs, they can be NMOS or PMOS transistors. A diode is formed between the source and drain of each MOSFET, which serves as the body diode of the MOSFET.

[0071] Taking the first switch M1 and the second switch M2 as NMOS transistors as an example, in specific implementation, refer to... Figure 2 The drain of the first switching transistor M1 is connected to the first terminal of the first energy storage inductor L1 and the source of the second switching transistor M2, and the drain of the second switching transistor M2 is connected to the second capacitor.

[0072] In another embodiment, the energy storage circuit 12 may include:

[0073] The first capacitor C1 is connected in parallel with the DC power supply 11;

[0074] First energy storage inductor L1; the first terminal of the first energy storage inductor L1 is connected to the first terminal of the first capacitor C1;

[0075] First switching transistor M1; the first end of the first switching transistor M1 is connected to the second end of the first energy storage inductor L1, and the second end of the first switching transistor M1 is connected to the second end of the first capacitor C1.

[0076] And a second switch M2; the first end of the second switch M2 is connected to the second end of the first energy storage inductor L1 and the first end of the first switch M1; the second end of the second switch M2 is connected to the energy storage device 13.

[0077] At this time, the energy storage circuit 12 only includes the first capacitor C1, the first energy storage inductor L1, the first switching transistor M1, and the second switching transistor M2, but does not include the second capacitor C2. That is to say, the second capacitor C2 can be omitted to filter the DC signal output by the DC power supply 11.

[0078] In specific implementation, refer to Figure 2 The energy storage device 13 may include a rechargeable battery V1, or other rechargeable devices, which are not limited here.

[0079] In some embodiments, refer to Figure 2 The energy storage device 13 may include a switching circuit S1 connected to the rechargeable battery V1. By controlling the on / off state of the switching circuit S1, the charging process of the rechargeable battery V1 can be controlled to stop.

[0080] Specifically, the switching circuit S1 can be a switching device, such as a MOSFET or IGBT. When the switching circuit is closed, the output of the energy storage circuit 12 can be input to the rechargeable battery V1; otherwise, the output of the energy storage circuit 12 cannot be input to the rechargeable battery V1.

[0081] In specific implementations, the boost circuit can have various structures, and no restrictions are imposed here.

[0082] In one embodiment of this utility model, the boost circuit may include: a first boost sub-circuit, a second boost sub-circuit, and a third capacitor. Wherein: the first boost sub-circuit is connected to the second terminal of the second switching transistor; the second boost sub-circuit is connected in parallel with the first boost sub-circuit; the third capacitor is connected in parallel with both the first and second boost sub-circuits; wherein the first boost sub-circuit and the second boost sub-circuit operate alternately.

[0083] In another embodiment of this utility model, the boost circuit may include: a fourth capacitor, a first boost sub-circuit, a second boost sub-circuit, and a third capacitor. The fourth capacitor is connected to the second terminal of the second switching transistor and the second terminal of the first switching transistor; the first boost sub-circuit is connected in parallel with the fourth capacitor; the second boost sub-circuit is connected in parallel with the fourth capacitor; and the third capacitor is connected in parallel with both the first and second boost sub-circuits. The first and second boost sub-circuits operate alternately.

[0084] By setting a fourth capacitor, which can be connected in parallel across the energy storage device, the DC signal output by the energy storage device can be filtered to remove ripple current, thereby further improving the reliability of the power supply system.

[0085] In practice, the circuit structures of the first boost sub-circuit and the second boost sub-circuit can be the same or different.

[0086] In one embodiment, reference is made to Figure 2 The first boost sub-circuit 141 and the second boost sub-circuit 142 have the same circuit structure.

[0087] Specifically, the first boost sub-circuit 141 includes: a first transformer T1, a third switch M3, and a first diode D1. The third switch M3 is located on the primary side of the first transformer T1, and its two ends are respectively connected to the two ends of the energy storage device 13.

[0088] The second boost circuit 142 includes a second transformer T2, a fourth switch M4, and a second diode D2. The fourth switch M4 is located on the primary side of the second transformer T2, and its two ends are connected to the two ends of the energy storage device 13.

[0089] When the third switch M3 is turned on, the DC signal output by the energy storage device 13 is boosted by the first transformer T1, output through the first diode D1, and then filtered by the third capacitor C3. When the fourth switch M4 is turned on, the DC signal output by the energy storage device 13 is boosted by the second transformer T2, output through the second diode D2, and then filtered by the third capacitor C3.

[0090] In specific implementation, the third switch M3 and the fourth switch M4 are alternately turned on, thereby causing the first transformer T1 and the second transformer T2 to operate alternately. The first boost sub-circuit 141 and the second boost sub-circuit 142 form an interleaved flyback circuit, which alternately boosts the DC signal output by the energy storage device 13, thereby reducing the ripple output to the AC power grid and further improving the reliability of the power supply system.

[0091] In a specific implementation, the first control signal used to control the on / off state of the third switch M3 and the second control signal used to control the on / off state of the fourth switch M4 have a fixed phase difference, but the duty cycle of each control signal is adjustable. This allows the on / off time of the third switch M3 and the fourth switch M4 to be changed, thereby adjusting the boosted voltage.

[0092] In specific implementations, the third switch M3 and the fourth switch M4 can be MOSFETs, IGBTs, or other semiconductor devices. When the third switch M3 and the fourth switch M4 are MOSFETs, they can be NMOS or PMOS transistors. A diode is formed between the source and drain of each MOSFET, which serves as the body diode of the MOSFET.

[0093] Taking the third switch M3 and the fourth switch M4 as NMOS transistors as an example, in specific implementation, refer to... Figure 2 The drain of the third switch M3 is connected to the first transformer T1, the source of the third switch M3 is connected to the source of the fourth switch M4, and the drain of the fourth switch M4 is connected to the second transformer T2.

[0094] In one embodiment, the energy storage circuit 12 includes a second capacitor C2. In this case, the boost circuit 14 may or may not include a fourth capacitor C4.

[0095] In another embodiment, the boost circuit 14 includes a fourth capacitor C4. In this case, the energy storage circuit 12 may or may not include a second capacitor C2.

[0096] In specific implementation, refer to Figure 2 The DC / AC converter 15 may include: a third diode D3, a fourth diode D4, a fifth switch M5, and a sixth switch M6. The third diode D3 and the fifth switch M5 are connected in series. The fourth diode D4 and the sixth switch M6 are connected in series. The branch formed by the series connection of the third diode D3 and the fifth switch M5 is connected in parallel with the branch formed by the series connection of the fourth diode D4 and the fifth switch M5.

[0097] When the fifth switch M5 is turned on, the sixth switch M6 is turned off. At this time, the boosted DC signal output from the boost circuit 14 is input to the AC mains via the fourth diode D4 and then flows out through the fifth switch M5. When the fifth switch M5 is turned off, the sixth switch M6 is turned on. At this time, the boosted DC signal output from the boost circuit 14 is input to the AC mains via the third diode D3 and then flows out through the sixth switch M6.

[0098] In a specific implementation, the power supply system may include only one power supply unit. In this case, the energy storage device may store only the electrical energy output by a DC power supply.

[0099] In some embodiments, the power supply system may include two or more power supply units. The two or more power supply units are connected in parallel and share the same energy storage device and the same DC / AC converter.

[0100] For example, refer to Figure 3 The power supply system may include three power supply units, which share the same energy storage device 13 and the same DC / AC converter 15. Specifically, the power supply system may include a first power supply unit, a second power supply unit, and a third power supply unit. The first power supply unit includes a first DC power supply 111, a first energy storage circuit 121, an energy storage device 13, a first boost circuit 141, and a DC / AC converter 15. The second power supply unit may include a second DC power supply 112, a second energy storage circuit 122, an energy storage device 13, a second boost circuit 141, and a DC / AC converter 15. The third power supply unit may include a third DC power supply 113, a second energy storage circuit 123, an energy storage device 13, a second boost circuit 143, and a DC / AC converter 15.

[0101] The energy storage device 13 can store the outputs of the first DC power supply 111, the second DC power supply 112 and the third DC power supply 113, and when needed, it can be inverted by the same DC / AC converter 15 and supplied to the AC power grid.

[0102] Taking the power supply system comprising two power supply units as an example, the circuit structure of the power supply system is as follows: Figure 4 As shown.

[0103] Reference Figure 4 The DC power output from the first DC power supply 111 can be stored in the energy storage device 13 via the first energy storage circuit 121. The DC signal output from the energy storage device 13 is boosted by the first boost circuit 141 and then inverted by the first DC / AC converter 151 to finally supply the AC power grid.

[0104] The DC power output from the second DC power supply 112 can be stored in the energy storage device 13 via the second energy storage circuit 122. The DC signal output from the energy storage device 13 is boosted by the second boost circuit 142 and then inverted by the second DC / AC converter 152 to finally supply the AC power grid.

[0105] In specific implementations, the first boost circuit 141 and the second boost circuit 142 can each be equipped with an independent third capacitor, or they can share the same third capacitor. When the number of power supply units exceeds two, the boost circuits of multiple power supply units can also share the same third capacitor.

[0106] In a specific implementation, the power supply system may further include a controller, which is adapted to control the operation of the power supply system. Specifically, refer to... Figure 2 The controller is adapted to control the on / off state of the first switch M1 and the second switch M2 in the energy storage circuit 12, and is also adapted to control the on / off state of the third switch M3 and the fourth switch M4 in the boost circuit 14.

[0107] In practice, when the power supply system includes two or more power supply units, some or all of the power supply units can be controlled by the same controller to achieve charging and discharging control during the power supply process.

[0108] In some embodiments, the controller is also adapted to control the switching on and off of the switching transistors in the DC / AC converter, thereby achieving inversion.

[0109] In specific implementations, the controller can be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0110] The solution of this utility model can store the DC power output from the DC power supply as needed, and then discharge it as needed, thereby better meeting diverse power supply needs.

[0111] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A power supply system, characterized in that, include: At least one power supply unit, the power supply unit comprising: a DC power supply, an energy storage circuit, an energy storage device, a boost circuit and a DC / AC converter, wherein: the energy storage circuit has an input terminal coupled to the DC power supply and an output terminal coupled to the energy storage device, and is adapted to store the DC power output by the DC power supply into the energy storage device; The boost circuit has its input terminal coupled to the energy storage device and its output terminal coupled to the DC / AC converter, and is suitable for boosting the DC signal output by the energy storage device. The DC / AC converter has its input terminal coupled to the boost circuit and its output terminal coupled to the AC power grid. It is suitable for inverting the boosted DC signal to obtain an AC signal suitable for input to the AC power grid and output to the AC power grid.

2. The power supply system as described in claim 1, characterized in that, The energy storage circuit includes: The first capacitor is connected in parallel with the DC power supply; A first energy storage inductor, wherein a first terminal of the first energy storage inductor is connected to a first terminal of the first capacitor; A first switching transistor, wherein a first terminal of the first switching transistor is connected to a second terminal of the first energy storage inductor, and a second terminal of the first switching transistor is connected to a second terminal of the first capacitor; The second switching transistor has a first terminal connected to the second terminal of the first energy storage inductor and the first terminal of the first switching transistor, and the second terminal of the second switching transistor is connected to the second capacitor. And the second capacitor, which is connected in parallel with the energy storage device.

3. The power supply system as described in claim 2, characterized in that, The boost circuit includes: The first boost sub-circuit is connected to the second terminal of the second switching transistor; The second boost sub-circuit is connected in parallel with the first boost sub-circuit. And a third capacitor, which is connected in parallel with the first boost sub-circuit and the second boost sub-circuit; The first boost sub-circuit and the second boost sub-circuit operate alternately.

4. The power supply system as described in claim 1, characterized in that, The energy storage circuit includes: The first capacitor is connected in parallel with the DC power supply; First energy storage inductor; the first terminal of the first energy storage inductor is connected to the first terminal of the first capacitor; first switching transistor; the first terminal of the first switching transistor is connected to the second terminal of the first energy storage inductor, and the second terminal of the first switching transistor is connected to the second terminal of the first capacitor; And a second switching transistor; the first end of the second switching transistor is connected to the second end of the first energy storage inductor and the first end of the first switching transistor; the second end of the second switching transistor is connected to the energy storage device.

5. The power supply system as described in claim 4, characterized in that, The boost circuit includes: The fourth capacitor is connected to the second terminal of the second switching transistor and the second terminal of the first switching transistor; The first boost circuit is connected in parallel with the fourth capacitor; The second boost circuit is connected in parallel with the fourth capacitor; And a third capacitor, which is connected in parallel with the first boost sub-circuit and the second boost sub-circuit; The first boost sub-circuit and the second boost sub-circuit operate alternately.

6. The power supply system as described in claim 3 or 5, characterized in that, The first boost sub-circuit has the same structure as the second boost sub-circuit.

7. The power supply system as described in claim 6, characterized in that, The first boost circuit includes: a first transformer; The third switching transistor is located on the primary side of the first transformer; The first diode is located on the secondary side of the first transformer.

8. The power supply system as described in claim 1, characterized in that, The energy storage device includes a rechargeable battery.

9. The power supply system as described in claim 8, characterized in that, The energy storage device further includes a switching circuit connected to the rechargeable battery.

10. The power supply system as described in claim 1, characterized in that, The DC power source is a photovoltaic panel.

11. The power supply system as described in claim 1, characterized in that, It includes two or more power supply units, which are connected in parallel and share the same energy storage device and the same DC / AC converter.

12. The power supply system as described in claim 1, characterized in that, Also includes: A controller, the controller being adapted to control the operation of the power supply system.

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