Switching circuit and power supply system

Abstract

The utility model discloses a switching circuit and a power supply system, the switching circuit comprises a control unit and a switching circuit, the controlled end of the switching circuit is electrically connected with the control end of the control unit; the input end of the first charging circuit is electrically connected with the input end of the rectifying circuit of the first power supply circuit, the output end of the first charging circuit is electrically connected with the power supply access end of the first battery circuit, and the power supply output end of the first battery circuit is electrically connected with the first end of the switching circuit; the input end of the second charging circuit is electrically connected with the input end of the rectifying circuit of the second power supply circuit, the output end of the second charging circuit is electrically connected with the power supply access end of the second battery circuit, and the power supply output end of the second battery circuit is electrically connected with the second end of the switching circuit; the utility model aims to solve the technical problem that the time for emergency power supply to a load is shortened under the condition that the inverter of one power supply circuit fails.

Description

TECHNICAL FIELD

[0001] The utility model relates to power supply technical field especially relates to a switching circuit and power supply system. BACKGROUND

[0002] The existing UPS power supply circuit includes rectifier, PFC module and inverter in series, first, the AC power of power grid is changed into DC power through rectifier, then the DC power is corrected through PFC module, and then the inverter is changed into AC power for AC load, so as to provide stable and reliable AC power supply for various application scenarios. The existing UPS power supply circuit also includes a backup battery for emergency power supply for the load when the power grid is powered off.

[0003] The inverter of the UPS power supply circuit has a certain failure risk, and when the inverter fails, the backup battery cannot discharge to the load through the inverter, so that the UPS power supply circuit loses the emergency power supply capability after the power failure. Most of the existing technologies use 2N mode UPS power supply circuit to supply power to the load, that is, two UPS power supply circuits supply power to the same load, and if the inverter of one of the UPS power supply circuits is abnormal, the number of UPS power supply circuits for emergency power supply to the load will be reduced when the power is off, thereby shortening the time of emergency power supply to the load. SUMMARY

[0004] The main purpose of the utility model is to provide a switching circuit and power supply system, which aims to solve the technical problem of shortening the time of emergency power supply to the load when the inverter of one of the UPS power supply circuits fails.

[0005] To achieve the above purpose, the utility model provides a switching circuit applied to a power supply system, the power supply system includes a first power supply circuit and a second power supply circuit, and a first monitoring system and a second monitoring system, the first monitoring system is used for detecting the working state of the inverter circuit of the first power supply circuit, and outputting a first abnormal signal when the inverter circuit of the first power supply circuit is abnormal, the second monitoring system is used for detecting the working state of the second power supply circuit, and outputting a second abnormal signal when the inverter circuit of the second power supply circuit is abnormal, and the switching circuit includes:

[0006] A control unit is connected with the first monitoring system and the second monitoring system respectively;

[0007] A switching circuit is electrically connected with the control terminal of the control unit;

[0008] The first charging circuit and the first battery circuit, the input end of the first charging circuit is electrically connected with the input end of the rectifier circuit of the first power supply circuit, the output end of the first charging circuit is electrically connected with the power input end of the first battery circuit, and the power output end of the first battery circuit is electrically connected with the input end of the PFC module of the first power supply circuit and the first end of the switch circuit respectively;

[0009] The second charging circuit and the second battery circuit, the input end of the second charging circuit is electrically connected with the input end of the rectifier circuit of the second power supply circuit, the output end of the second charging circuit is electrically connected with the power input end of the second battery circuit, and the power output end of the second battery circuit is electrically connected with the input end of the PFC module of the second power supply circuit and the second end of the switch circuit respectively;

[0010] The control unit is used for controlling the switch circuit to turn on the passage between the output end of the first battery circuit and the input end of the PFC module of the second power supply circuit when the first abnormal signal is received, and is also used for controlling the switch circuit to turn on the passage between the output end of the second battery circuit and the input end of the PFC module of the first power supply circuit when the second abnormal signal is received.

[0011] In an embodiment, the first battery circuit comprises:

[0012] The first battery module, the first diode and the second diode, the anode of the first diode is electrically connected with the output end of the first charging circuit, the cathode of the first diode is electrically connected with the power input end of the first battery module, the power output end of the first battery module is electrically connected with the first end of the switch circuit and the anode of the second diode respectively, and the cathode of the second diode is electrically connected with the input end of the PFC module of the first power supply circuit.

[0013] The second battery circuit comprises:

[0014] The second battery module, the third diode and the fourth diode, the anode of the third diode is electrically connected with the output end of the second charging circuit, the cathode of the third diode is electrically connected with the power input end of the second battery module, the power output end of the second battery module is electrically connected with the second end of the switch circuit and the anode of the fourth diode respectively, and the cathode of the fourth diode is electrically connected with the input end of the PFC module of the second power supply circuit.

[0015] In an embodiment, the anode of the third diode is electrically connected with the power output end of the first battery module, and the cathode of the third diode is electrically connected with the first end of the switch circuit and the input end of the PFC module of the first power supply circuit respectively;

[0016] An anode of the fourth diode is electrically connected with a power output end of the second battery module, and a cathode of the fourth diode is electrically connected with a second end of the switch circuit and an input end of a PFC module of the second power supply circuit respectively.

[0017] In an embodiment, the switch circuit comprises:

[0018] A relay, a first end of the relay is electrically connected with an output end of the first battery circuit and an input end of a PFC module of the first power supply circuit respectively, a second end of the relay is electrically connected with an output end of the second battery circuit and a PFC module of the second power supply circuit respectively, and a controlled end of the relay is electrically connected with a control end of the control unit.

[0019] In an embodiment, the switch circuit further comprises:

[0020] A parallel machine controller, a signal receiving end of the parallel machine controller is electrically connected with a control end of the control unit, and a control end of the parallel machine controller is electrically connected with a controlled end of the switch circuit.

[0021] The utility model also proposes a power supply system, including first power supply circuit, second power supply circuit, first monitoring system, second monitoring system and like above any one of the switch circuit, the input of first power supply circuit and the input of second power supply circuit all are electrically connected with the switch circuit.

[0022] In an embodiment, the first power supply circuit further comprises:

[0023] A first switch assembly, a first end of the first switch assembly is connected with a commercial power supply, a second end of the first switch assembly is connected with a load, and a controlled end of the first switch assembly is connected with a control end of the control unit.

[0024] The second power supply circuit further comprises:

[0025] A second switch assembly, a first end of the first switch assembly is connected with a commercial power supply, a second end of the first switch assembly is connected with a load, and a controlled end of the second switch assembly is connected with a control end of the control unit.

[0026] In an embodiment, the first switch assembly and the second switch assembly are both static transfer switches.

[0027] The utility model discloses a technical scheme including first charging circuit and first battery circuit, second charging circuit and second battery circuit, switching circuit and control unit, and control unit is connected with first monitoring system and second monitoring system respectively, and first monitoring system is used for outputting first exception signal when the inverter circuit of first power supply circuit appears exception, and second monitoring system is used for outputting second exception signal when the inverter circuit of second power supply circuit appears exception, and control unit is used for controlling switching circuit to switch on the passway between the output end of first battery circuit and the input end of PFC module of second power supply circuit when receiving first exception signal, and also is used for controlling switching circuit to switch on the passway between the output end of second battery circuit and the input end of PFC module of first power supply circuit when receiving second exception signal. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical scheme in the embodiment of the utility model or prior art, the following will be briefly introduced the drawing needed to be used in the embodiment or prior art description, and obviously, the drawing in the following description is only some embodiments of the utility model, and for the ordinary skilled person in the art, under the premise of not paying the creative labor, other drawings can also be obtained according to the structure shown in these drawings.

[0029] Figure 1 It is the module schematic diagram of an embodiment of the utility model;

[0030] Figure 2 It is the module schematic diagram of another embodiment of the utility model;

[0031] Figure 3 It is the circuit structure schematic diagram of an embodiment of the utility model;

[0032] Figure 4 It is the circuit structure schematic diagram of still another embodiment of the utility model.

[0033] EXPLANATION OF DRAWINGS:

[0034] 11, first charging circuit; 12, first battery circuit; 21, second charging circuit; 22, second battery circuit; 30, switching circuit; 40, parallel operation controller; 50, first switching assembly; 60, second switching assembly; 70, control unit; 80, first monitoring system; 90, second monitoring system.

[0035] The purposes, functional features and advantages will be further described in combination with embodiments with reference to the drawings. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0037] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition, etc. between the components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.

[0038] In addition, if the embodiments of the present application involve descriptions of "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In addition, "and / or" or "and / or" appearing throughout the text means that the three parallel schemes are included, for example, "A and / or B" includes A scheme, or B scheme, or A and B simultaneously satisfy the scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0039] The existing UPS power supply circuit includes a rectifier, a PFC module and an inverter connected in series. First, the AC power of the power grid is converted into DC power through the rectifier, then the DC power is corrected through the PFC module, and then the AC load available AC power is converted through the inverter, thereby providing stable and reliable AC power for various application scenarios. The existing UPS power supply circuit also includes a backup battery for emergency power supply to the load through the PFC module and the inverter in sequence when the power grid is powered off.

[0040] The inverter of the UPS power supply circuit has a certain failure risk, and when the inverter fails, the standby battery of the UPS power supply circuit cannot be discharged to the load through the inverter, so that the UPS power supply circuit loses the ability of emergency power supply after the mains power is cut off. Most of the UPS power supply circuits in the prior art use 2N mode to supply power to the load, that is, two UPS power supply circuits supply power to the same load, and if the inverter of one of the UPS power supply circuits is abnormal, the number of UPS power supply circuits for emergency power supply to the load will be reduced when the power is cut off, thereby shortening the time length of emergency power supply to the load.

[0041] Therefore, the utility model provides a switching circuit and a power supply system, which aims to solve the technical problem of shortening the time length of emergency power supply to the load when the inverter of one of the UPS power supply circuits fails.

[0042] Reference Figure 1 In an embodiment of the utility model, the switching circuit is applied to a power supply system, the power supply system includes a first power supply circuit and a second power supply circuit, a first monitoring system 80 and a second monitoring system 90, the first monitoring system 80 is used for detecting the working state of the inverter circuit of the first power supply circuit, and outputs a first abnormal signal when the inverter circuit of the first power supply circuit is abnormal, the second monitoring system 90 is used for detecting the working state of the second power supply circuit, and outputs a second abnormal signal when the inverter circuit of the second power supply circuit is abnormal, and the switching circuit includes:

[0043] A control unit 70 is connected with the first monitoring system 80 and the second monitoring system 90 respectively;

[0044] A switching circuit 30, the controlled end of the switching circuit 30 is electrically connected with the control end of the control unit 70;

[0045] A first charging circuit 11 and a first battery circuit 12, the input end of the first charging circuit 11 is electrically connected with the input end of the rectifier circuit of the first power supply circuit, the output end of the first charging circuit 11 is electrically connected with the power access end of the first battery circuit 12, and the power output end of the first battery circuit 12 is electrically connected with the input end of the PFC module of the first power supply circuit and the first end of the switching circuit 30 respectively;

[0046] The second charging circuit 21 has an input end electrically connected with the input end of the rectifier circuit of the second power supply circuit, and an output end electrically connected with the power input end of the second battery circuit 22. The power output end of the second battery circuit 22 is electrically connected with the input end of the PFC module of the second power supply circuit and the second end of the switch circuit 30, respectively.

[0047] The control unit 70 is configured to control the switch circuit to turn on the path between the output end of the first battery circuit and the input end of the PFC module of the second power supply circuit when the first abnormal signal is received, and to control the switch circuit to turn on the path between the output end of the second battery circuit and the input end of the PFC module of the first power supply circuit when the second abnormal signal is received.

[0048] In the embodiment, the switch circuit 30 includes any bidirectional switch such as a relay or a single-pole single-throw switch.

[0049] In the embodiment, the first monitoring system 80 can measure the input / output voltage of the inverter circuit of the first power supply circuit, and determine that the inverter circuit of the first power supply circuit is abnormal when the input / output voltage deviates from a preset value. The second monitoring system 90 has the same function as the first monitoring system 80, and will not be described here.

[0050] In the embodiment, the controlled end of the first battery circuit 12 and the controlled end of the second battery circuit 22 are electrically connected with the control end of the control unit 70. The control unit 70 is configured to control the first battery circuit 12 and the second battery circuit 22 to work when the mains power is off, so as to provide emergency power supply for the load.

[0051] In the embodiment, the first charging circuit 11 and the second charging circuit 21 are devices or circuits for converting an external power supply (such as mains power) into voltage and current suitable for charging the battery circuit, and generally include a rectifier (for converting alternating current into direct current), a filter (for smoothing the output of direct current), and possibly a voltage regulator (for ensuring stable output voltage).

[0052] In another embodiment, the input end of the first charging circuit 11 and the input end of the second charging circuit 21 can be electrically connected with the output end of the rectifier circuit of the first power supply circuit and the output end of the rectifier circuit of the second power supply circuit, respectively, so that the first charging circuit 11 and the second charging circuit 21 can directly obtain the direct current output by the rectifier circuit. The first charging circuit 11 and the second charging circuit 21 are configured to perform boost / voltage reduction on the direct current and charge the first battery circuit 12 and the second battery circuit 22, respectively.

[0053] In the embodiment, the switching circuit can further comprise a parallel controller 40, and the parallel controller 40 is configured to control the switch circuit 30 to be turned on / off when receiving the relevant signal transmitted by the control unit 70. It can be understood that the parallel controller can also be taken over by the control unit 70 to perform the corresponding functions.

[0054] Specifically, the technical scheme of the utility model discloses first charging circuit 11 and first battery circuit 12, second charging circuit 21 and second battery circuit 22, switch circuit 30 and control unit 70, control unit 70 is connected with first monitoring system 80 and second monitoring system 90 respectively, first monitoring system 80 is used to output first exception signal when the inverter circuit of first power supply circuit appears abnormal, second monitoring system 90 is used to output second exception signal when the inverter circuit of second power supply circuit appears abnormal, control unit 70 is used to control switch circuit to turn on the passageway between the output end of first battery circuit 12 and the input end of the PFC module of second power supply circuit when receiving first exception signal, and it is also used to control switch circuit 30 to turn on the passageway between the output end of second battery circuit 22 and the input end of the PFC module of first power supply circuit when receiving second exception signal. Thus, in actual application, when the inverter circuit of one of the power supply circuits fails, first battery circuit 12 and second battery circuit 22 jointly serve as the backup battery of the other power supply circuit, which is equivalent to doubling the battery capacity of the backup battery of the other power supply circuit, so that the emergency power supply time of the other power supply circuit for the load is doubled in the case of power failure, thereby ensuring that the total emergency power supply time remains basically unchanged and avoiding the situation that the emergency power supply time for the load is shortened due to the loss of emergency power supply capability of one of the power supply circuits.

[0055] In addition, in the prior art, when the backup battery of the UPS power supply circuit is damaged, the UPS power supply circuit will stop supplying power to the load if the power grid is powered off. When the load is a server, server downtime means business interruption, which will have a serious impact on the operation of the enterprise and the customer experience. In order to solve the above problems, the existing solution is to install multiple backup batteries to switch to another backup battery when one of the backup batteries is damaged, but this will result in an increase in the cost and space occupation area of the UPS power supply circuit. Compared with the existing UPS power supply circuit, the power supply system applying the switching circuit of the utility model does not need to configure multiple backup batteries for each power supply circuit. When the backup battery of one of the power supply circuits of the power supply system fails, the switching circuit of the utility model can switch the backup battery of another power supply circuit of the power supply system to provide power, thereby reducing the cost and reducing the occupied space of the power supply system.

[0056] It can be understood that the first end and the second end of the switch circuit 30 can also be connected with the input end of the inverter circuit of the first power supply circuit and the input end of the inverter circuit of the second power supply circuit respectively, the output end of the first battery circuit 12 can also be connected with the input end of the inverter circuit of the first power supply circuit, and the output end of the second battery circuit 22 can also be connected with the input end of the inverter circuit of the second power supply circuit. When the direct current parameters output by the battery circuit meet the actual requirements, the PFC module need not be used to process the direct current, and the direct current can be directly input to the inverter circuit.

[0057] It can be understood that the first power supply circuit and the second power supply circuit can also be standby power supply circuits of each other, for example, when the first power supply circuit fails to work, the control unit 70 controls the second power supply circuit to work, thereby ensuring continuous power supply to the load.

[0058] Reference Figure 2 In an embodiment of the utility model, the first battery circuit 12 comprises:

[0059] The first battery module, the first diode D1 and the second diode D2, the anode of the first diode D1 is connected with the output end of the first charging circuit 11, the cathode of the first diode D1 is connected with the power input end of the first battery module, the power output end of the first battery module is connected with the first end of the switch circuit 30 and the anode of the second diode D2 respectively, the cathode of the second diode D2 is connected with the input end of the PFC module of the first power supply circuit,

[0060] The second battery circuit 22 comprises:

[0061] The second battery module, the third diode D3 and the fourth diode D4, the anode of the third diode D3 is connected with the output end of the second charging circuit 21, the cathode of the third diode D3 is connected with the power input end of the second battery module, the power output end of the second battery module is connected with the second end of the switch circuit 30 and the anode of the fourth diode D4 respectively, the cathode of the fourth diode D4 is connected with the input end of the PFC module of the second power supply circuit.

[0062] In the embodiment, the first diode D1 and the third diode D3 are respectively used to prevent the current of the first battery module and the second battery module from flowing back to the first charging circuit 11 and the second charging circuit 21, and the second diode D2 and the fourth diode D4 are respectively used to prevent the direct current after the treatment of the rectifier circuit from flowing back to the first battery module and the second battery module, thereby protecting the safety of the charging circuit and the power supply system.

[0063] When the switch circuit 30 is turned on, the circuit connects the output end of the first battery module and the output end of the second battery module, in which case the first battery module and the second battery module can affect each other, for example, when the voltages of the two battery modules are inconsistent, if the first battery module and the second battery module are directly connected in parallel, voltage fluctuation can occur. The battery module with high voltage can charge the battery module with low voltage until the voltages of the two battery modules are equal, in which process heat accumulation inside the battery module, battery performance degradation or even damage can occur.

[0064] To solve the above problems, reference is made to Figure 3 In the embodiment, the anode of the third diode D3 is electrically connected with the power output end of the first battery module, and the cathode of the third diode D3 is electrically connected with the first end of the switch circuit 30 and the input end of the PFC module of the first power circuit respectively.

[0065] The anode of the fourth diode D4 is electrically connected with the power output end of the second battery module, and the cathode of the fourth diode D4 is electrically connected with the second end of the switch circuit 30 and the input end of the PFC module of the second power circuit respectively.

[0066] In the embodiment, when the switch circuit 30 is turned on, the output end of the first battery module and the output end of the second battery module are isolated from each other due to the unidirectional conduction characteristic of the diode. In this way, by adding the diode for isolation, the mutual influence between the parallel battery modules can be reduced, thereby improving the stability and reliability of the power supply system.

[0067] The utility model also proposes a kind of power supply system, including first power circuit, second power circuit, first monitoring system, second monitoring system and the switching circuit as described above;The input end of the first power circuit and the input end of the second power circuit are electrically connected with the switching circuit.

[0068] It is worth noting that, since the power supply system of the utility model is based on the above-mentioned switching circuit, the embodiments of the power supply system of the utility model include all the technical solutions of all the embodiments of the above-mentioned switching circuit, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0069] Reference Figure 4 In an embodiment of the utility model, the first power circuit further includes:

[0070] First switch assembly 50, the first end of the first switch assembly 50 is connected to commercial power, and the second end of the first switch assembly 50 is connected to load;

[0071] The second power circuit further includes:

[0072] The first end of the first switch assembly 50 is connected to the mains, and the second end of the first switch assembly 50 is connected to the load.

[0073] In the embodiment, the first switch assembly 50 and the second switch assembly 60 are both static transfer switches.

[0074] In the embodiment, the input end of the rectifier circuit of the first power supply circuit and the first end of the first switch assembly 50 are both connected to the mains. Under normal circumstances, the first switch assembly 50 is turned on, and the mains directly supplies power to the load through the first switch assembly 50. The second switch assembly 60 has the same function as the first switch assembly 50, which will not be described one by one. When the quality of the voltage of the mains decreases (such as voltage fluctuation, excessively low voltage, voltage distortion, etc.), the mains cannot continue to provide stable and reliable power supply for the load. In this regard, the first monitoring system 70 and the second monitoring system 80 are also used to detect the quality of the voltage of the mains, and when the quality of the voltage of the mains is detected to decrease, output corresponding control signals to the control unit 70, so that the control unit 70 controls the first switch assembly 50 / the second switch assembly 60 to be turned off. The mains can be converted into stable and reliable alternating current after being processed by the rectifier circuit, the PFC module and the inverter circuit of the first power supply circuit / the second power supply circuit in turn, which is suitable for supplying power to the load. In this way, the power supply system of the utility model has the functions of voltage quality monitoring and protection, can timely discover and respond to voltage quality problems, and prevent damage to the load.

[0075] The above is only an exemplary embodiment of the utility model, and does not limit the patent range of the utility model, and any equivalent structural transformation made by using the utility model specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection range of the utility model.

Claims

1. A switching circuit applied to a power supply system, the power supply system comprising a first power supply circuit and a second power supply circuit, and a first monitoring system and a second monitoring system, the first monitoring system being configured to detect an operating state of an inverter circuit of the first power supply circuit and output a first abnormality signal when the inverter circuit of the first power supply circuit is abnormal, the second monitoring system being configured to detect an operating state of an inverter circuit of the second power supply circuit and output a second abnormality signal when the inverter circuit of the second power supply circuit is abnormal, characterized in that, The switching circuit comprises: a control unit connected with the first monitoring system and the second monitoring system respectively; a switching circuit with a control end electrically connected with a control end of the control unit; a first charging circuit and a first battery circuit, an input end of the first charging circuit is electrically connected with an input end of a rectifier circuit of the first power supply circuit, an output end of the first charging circuit is electrically connected with a power input end of the first battery circuit, and a power output end of the first battery circuit is electrically connected with an input end of a PFC module of the first power supply circuit and a first end of the switching circuit respectively; a second charging circuit and a second battery circuit, an input end of the second charging circuit is electrically connected with an input end of a rectifier circuit of the second power supply circuit, an output end of the second charging circuit is electrically connected with a power input end of the second battery circuit, and a power output end of the second battery circuit is electrically connected with an input end of a PFC module of the second power supply circuit and a second end of the switching circuit respectively; the control unit is configured to control the switching circuit to turn on a path between the output end of the first battery circuit and the input end of the PFC module of the second power supply circuit when the first abnormal signal is received, and control the switching circuit to turn on a path between the output end of the second battery circuit and the input end of the PFC module of the first power supply circuit when the second abnormal signal is received.

2. The switching circuit of claim 1, wherein, The first battery circuit comprises: a first battery module, a first diode and a second diode, an anode of the first diode is electrically connected with the output end of the first charging circuit, a cathode of the first diode is electrically connected with a power input end of the first battery module, a power output end of the first battery module is electrically connected with the first end of the switching circuit and an anode of the second diode respectively, and a cathode of the second diode is electrically connected with the input end of the PFC module of the first power supply circuit; The second battery circuit comprises: a second battery module, a third diode and a fourth diode, an anode of the third diode is electrically connected with the output end of the second charging circuit, a cathode of the third diode is electrically connected with a power input end of the second battery module, a power output end of the second battery module is electrically connected with the second end of the switching circuit and an anode of the fourth diode respectively, and a cathode of the fourth diode is electrically connected with the input end of the PFC module of the second power supply circuit.

3. The switching circuit of claim 2, wherein, The anode of the third diode is electrically connected with the power output end of the first battery module, and the cathode of the third diode is electrically connected with the first end of the switching circuit and the input end of the PFC module of the first power supply circuit respectively; The anode of the fourth diode is electrically connected with the power output end of the second battery module, and the cathode of the fourth diode is electrically connected with the second end of the switching circuit and the input end of the PFC module of the second power supply circuit respectively.

4. The switching circuit of claim 1, wherein, The switching circuit comprises: A relay, a first end of the relay is electrically connected with the output end of the first battery circuit and the input end of the PFC module of the first power supply circuit respectively, a second end of the relay is electrically connected with the output end of the second battery circuit and the PFC module of the second power supply circuit respectively, and a controlled end of the relay is electrically connected with the control end of the control unit.

5. The switching circuit of claim 1, wherein, The switching circuit further comprises: A parallel operation controller, a signal receiving end of the parallel operation controller is electrically connected with the control end of the control unit, and a control end of the parallel operation controller is electrically connected with the controlled end of the switching circuit.

6. A power supply system characterized by comprising: The switching circuit comprises a first power supply circuit, a second power supply circuit, a first monitoring system, a second monitoring system and the switching circuit as claimed in any one of claims 1 to 5, and the input end of the first power supply circuit and the input end of the second power supply circuit are electrically connected with the switching circuit.

7. The power supply system of claim 6, wherein, The first power supply circuit further comprises: A first switch assembly, a first end of the first switch assembly is connected with the commercial power supply, a second end of the first switch assembly is connected with the load, and a controlled end of the first switch assembly is connected with the control end of the control unit. The second power supply circuit further comprises: A second switch assembly, a first end of the first switch assembly is connected with the commercial power supply, a second end of the first switch assembly is connected with the load, and a controlled end of the second switch assembly is connected with the control end of the control unit.

8. The power supply system of claim 7, wherein, The first switch assembly and the second switch assembly are both static transfer switches.

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