Power supply automatic switching circuit and power distribution micro-grid system

Abstract

The utility model discloses a power supply automatic switching circuit and a power distribution micro-grid system, and belongs to the technical field of electronic circuits. The circuit is characterized in that a first switch is connected with an output end through a normally open main contact of a first contactor; the second switch is connected to the first switch; a normally closed auxiliary contact of the second contactor is connected with the second switch and a coil of the first contactor; the first contactor coil is connected with the first switch; the third switch is connected with the output end through a normally open main contact of the second contactor; the fourth switch is connected with the third switch; a normally closed auxiliary contact of the first contactor is connected with a fourth switch and a second contactor coil; the second contactor coil is connected with the third switch; before the first switch is closed, the third switch is kept open. According to the application, the two contactors are interlocked, so that when the main supply sub-circuit is abnormal, the standby sub-circuit can be automatically switched to supply power, a user does not need to manually switch the standby power supply, the emergency and security power utilization requirements of the user can be ensured, and the safe power utilization of the user is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to an automatic power switching circuit and a power distribution microgrid system. Background Art

[0002] Currently, with the development of new energy technologies, more and more household users choose to access new energy power generation.

[0003] In the related technology, the two systems of mains access and renewable energy generation access are usually coexisting and supplying power separately. However, in actual applications, it is found that in this operation mode of coexistence of two systems and separate power supply, when the mains power fails, it cannot automatically switch to renewable energy generation as a backup power source for power supply, and users are usually required to manually switch the power supply mode, which seriously threatens the power consumption and personal safety of users.

[0004] In summary, the technical problems existing in the relevant technologies need to be improved. Utility Model Content

[0005] The embodiment of the present application provides an automatic power switching circuit and a power distribution microgrid system. By interlocking two contactors, it is possible to automatically switch to a backup sub-circuit for power supply when an abnormal condition occurs in the main supply sub-circuit, and there is no need for the user to manually switch the backup power supply, thereby ensuring the user's emergency and security power needs and ensuring the user's safe use of electricity.

[0006] On the one hand, an embodiment of the present application provides an automatic power switching circuit, the circuit comprising: a main supply sub-circuit, a standby sub-circuit;

[0007] The main power supply subcircuit includes a mains power input terminal, a first switch, a second switch, a first contactor and an output terminal;

[0008] The standby subcircuit includes a standby power input terminal, a third switch, a fourth switch, a second contactor, and an output terminal;

[0009] The mains input terminal includes a first phase line input terminal and a first neutral line input terminal, the first switch is a double-pole single-throw switch, and one end of the first switch is respectively connected to the first phase line input terminal and the first neutral line input terminal;

[0010] The other end of the first switch is connected to the output end through a set of normally open main contacts of the first contactor;

[0011] One end of the second switch is connected to the other end of the first switch;

[0012] A set of normally closed auxiliary contacts of the second contactor connects the other end of the second switch and one pole of the coil of the first contactor;

[0013] The other pole of the coil of the first contactor is connected to the other end of the first switch;

[0014] The backup power supply input terminal includes a second phase line input terminal and a second neutral line input terminal, the third switch is a double-pole single-throw switch, and one end of the third switch is respectively connected to the second phase line input terminal and the second neutral line input terminal;

[0015] The other end of the third switch is connected to the output end through a set of normally open main contacts of the second contactor;

[0016] One end of the fourth switch is connected to the other end of the third switch;

[0017] A set of normally closed auxiliary contacts of the first contactor is connected to the other end of the fourth switch and one pole of the coil of the second contactor;

[0018] The other pole of the coil of the second contactor is connected to the other end of the third switch;

[0019] Before the first switch is closed, the third switch remains open.

[0020] Optionally, the main supply subcircuit is further provided with a set of normally open auxiliary contacts of the second contactor;

[0021] After a group of normally open auxiliary contacts of the second contactor is connected in parallel with a group of normally closed auxiliary contacts of the second contactor, the other end of the second switch is connected to one pole of the coil of the first contactor.

[0022] Optionally, the main supply subcircuit further includes a first fuse;

[0023] The first fuse connects the first switch and the second switch.

[0024] Optionally, the standby subcircuit further includes a second fuse;

[0025] The second fuse connects the third switch and the fourth switch.

[0026] Optionally, the first switch and the third switch are double-pole single-throw knife switches.

[0027] Optionally, the second switch and the fourth switch are push button switches.

[0028] On the other hand, an embodiment of the present application provides a power distribution microgrid system, including: a mains input terminal, a distribution box, a control module, an inverter charging module, an energy storage module, a new energy power generation input terminal, and a new energy power generation controller;

[0029] The distribution box includes a main switch and a distribution box busbar; the control module is provided with any of the above-mentioned power automatic switching circuits;

[0030] The mains input terminal is connected to one end of the main switch;

[0031] The other end of the main switch is connected to the input end of the control module and the inverter charging module;

[0032] The new energy generation input terminal is connected to the new energy generation controller;

[0033] The new energy generation controller is connected to the inverter charging module and the energy storage module;

[0034] The inverter charging module is connected to the input end of the control module;

[0035] The output of the control module is connected to the busbar of the distribution box.

[0036] Optionally, the power distribution microgrid system includes a mains power priority operation mode and a renewable energy power generation priority operation mode.

[0037] Optionally, the inverter charging module is connected to the input end of the control module via a power connector.

[0038] Optionally, the new energy power generation input end is provided with any one of a distributed photovoltaic power generation interface, a breeze power generation interface or a small hydropower generation interface.

[0039] The embodiment of the present application interlocks the two contactors to automatically switch to the backup sub-circuit for power supply when an abnormal condition occurs in the main power supply sub-circuit, without the need for the user to manually switch the backup power supply, thereby ensuring the user's personal safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of the structure of the automatic power switching circuit provided in an embodiment of the present application;

[0041] Figure 2 It is a structural diagram of the power distribution microgrid system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0043] It is understood that the terms "first", "second", etc. used in this application can be used to describe various concepts in this article, but unless otherwise specified, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another concept. For example, without departing from the scope of the embodiment of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the words "if" and "if" as used herein can be interpreted as "at the time of" or "when" or "in response to determination".

[0044] The terms "at least one", "multiple", "each", "any", etc. used in this application, at least one includes one, two or more, multiple includes two or more, each refers to each of the corresponding multiple, and any refers to any one of the multiple.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0046] Currently, with the development of new energy technologies, more and more household users choose to access new energy power generation.

[0047] In the related technology, the two systems of mains access and renewable energy generation access are usually coexisting and supplying power separately. However, in actual applications, it is found that in this operation mode of coexistence of two systems and separate power supply, when the mains power fails, it cannot automatically switch to renewable energy generation as a backup power source for power supply, and users are usually required to manually switch the power supply mode, which seriously threatens the personal safety of users.

[0048] In view of this, an automatic power switching circuit and a power distribution microgrid system are provided in an embodiment of the present application, and the circuit includes: a first switch is connected to the output end through the normally open main contact of the first contactor; the second switch is connected to the first switch; the normally closed auxiliary contact of the second contactor is connected to the coil of the second switch and the first contactor; the coil of the first contactor is connected to the first switch; the third switch is connected to the output end through the normally open main contact of the second contactor; the fourth switch is connected to the third switch; the normally closed auxiliary contact of the first contactor is connected to the coil of the fourth switch and the second contactor; the coil of the second contactor is connected to the third switch; before the first switch is closed, the third switch is always kept open. By interlocking the two contactors, the present application can automatically switch to the backup subcircuit for power supply when an abnormal condition occurs in the main supply subcircuit, and there is no need for the user to manually switch the backup power supply, which can guarantee the user's emergency and security power needs and ensure the user's safe use of electricity.

[0049] The specific implementation of the embodiment of the present application is described in detail below in conjunction with the accompanying drawings. First, a power automatic switching circuit provided in the embodiment of the present application is described in conjunction with the accompanying drawings.

[0050] Please refer to Figure 1 , Figure 1 The schematic diagram of the structure of the automatic power switching circuit provided in the embodiment of the present application is shown, including: a main supply sub-circuit and a standby sub-circuit;

[0051] The main power supply subcircuit includes a mains input terminal, a first switch K1, a second switch K2, a first contactor and an output terminal;

[0052] The standby subcircuit includes a standby power input terminal, a third switch K3, a fourth switch K4, a second contactor and an output terminal;

[0053] The mains input terminal includes a first phase line input terminal L1in and a first neutral line input terminal N1in, the first switch K1 is a double-pole single-throw switch, and one end of the first switch K1 is connected to the first phase line input terminal L1in and the first neutral line input terminal N1in respectively;

[0054] The other end of the first switch K1 is connected to the output end through a group of normally open main contacts KM11 of the first contactor;

[0055] One end of the second switch K2 is connected to the other end of the first switch K1;

[0056] A set of normally closed auxiliary contacts KM22 of the second contactor connects the other end of the second switch K2 and one pole of the coil C1 of the first contactor;

[0057] The other pole of the coil C1 of the first contactor is connected to the other end of the first switch K1;

[0058] The backup power supply input terminal includes a second phase line input terminal L2in and a second neutral line input terminal N2in, the third switch K3 is a double-pole single-throw switch, and one end of the third switch K3 is connected to the second phase line input terminal L2in and the second neutral line input terminal N2in respectively;

[0059] The other end of the third switch K3 is connected to the output end through a group of normally open main contacts KM21 of the second contactor;

[0060] One end of the fourth switch K4 is connected to the other end of the third switch K3;

[0061] A set of normally closed auxiliary contacts KM12 of the first contactor are connected to the other end of the fourth switch K4 and one pole of the coil C2 of the second contactor;

[0062] The other pole of the coil C2 of the second contactor is connected to the other end of the third switch K3;

[0063] Before the first switch K1 is closed, the third switch K3 is always kept open.

[0064] Specifically, a main supply subcircuit and a standby subcircuit are provided in the power supply automatic switching circuit, and a main supply subcircuit is provided with a mains input terminal, a first switch K1, a second switch K2, a first contactor and an output terminal. The first contactor can be an AC contactor, and the output terminal is used to output electrical energy.

[0065] Furthermore, the mains input terminal includes a first phase line input terminal L1in and a first neutral line input terminal N1in, and the first switch K1 arranged in the main supply sub-circuit is a double-pole single-throw switch, one end of the first switch K1 is respectively connected to the first phase line input terminal L1in and the first neutral line input terminal N1in, and the other end of the first switch K1 is respectively connected to the output terminal through a group of normally open main contacts KM11 of the first contactor. Among them, a double-pole single-throw switch (Double Pole Single Throw, DPST) is a switch that can control two independent circuits at the same time. This switch has two independent input terminals and two independent output terminals, and the two circuits are connected or disconnected at the same time through one operation. Therefore, after one end of the first switch K1 is respectively connected to the first phase line input terminal L1in and the first neutral line input terminal N1in, the on-off status of the phase line and the neutral line on the main supply sub-circuit can be controlled at the same time.

[0066] Furthermore, a second switch K2 is also provided in the main supply subcircuit, and the second switch K2 can be opened and closed synchronously with the first switch K1. That is to say, when the first switch K1 is closed, the second switch K2 is also closed synchronously; when the first switch K1 is opened, the second switch K2 is also opened synchronously. One end of the second switch K2 is connected to the other end of the first switch K1, and a group of normally closed auxiliary contacts KM22 of the second contactor are connected between the other end of the second switch K2 and one pole of the coil C1 of the first contactor, and the other pole of the coil C1 of the first contactor is connected to the other end of the first switch K1.

[0067] It can be understood that when the coil C1 of the first contactor has not been energized, a group of normally open main contacts KM11 of the first contactor will remain in an open state, and the input AC power cannot be output. When the first switch K1 and the second switch K2 are closed synchronously, since the third switch K3 is always kept open before the first switch K1 is closed, a group of normally closed auxiliary contacts KM22 of the second contactor will remain in a closed state, and the input AC power will be conducted to the coil C1 of the first contactor, and the coil C1 of the first contactor is energized, thereby causing a group of normally open main contacts KM11 of the first contactor to actuate and become closed. The input AC power will be conducted to the output end through the main supply sub-circuit for output, and power the subsequent load.

[0068] The backup subcircuit is provided with a backup power input terminal, a third switch K3, a fourth switch K4, a second contactor and an output terminal. The backup power input to the backup power input terminal can be generated by a new energy source carried by the user, the second contactor can be an AC contactor, and the output terminal is used to output electric energy.

[0069] Furthermore, the backup power input terminal includes a second phase line input terminal L2in and a second neutral line input terminal N2in, and the third switch K3 provided in the backup subcircuit is a double-pole single-throw switch, one end of the third switch K3 is respectively connected to the second phase line input terminal L2in and the second neutral line input terminal N2in, and the other end of the third switch K3 is respectively connected to the output terminal through a group of normally open main contacts KM21 of the second contactor. The third switch K3 can simultaneously control the on-off status of the phase line and the neutral line on the backup subcircuit.

[0070] Furthermore, a fourth switch K4 is also provided in the standby subcircuit, and the fourth switch K4 can be opened and closed synchronously with the third switch K3. That is, when the third switch K3 is closed, the fourth switch K4 is also closed synchronously; when the third switch K3 is opened, the fourth switch K4 is also opened synchronously. One end of the fourth switch K4 is connected to the other end of the third switch K3, and a group of normally closed auxiliary contacts KM12 of the first contactor are connected between the other end of the fourth switch K4 and one pole of the coil C2 of the second contactor, and the other pole of the coil C2 of the second contactor is connected to the other end of the third switch K3.

[0071] It can be understood that the first contactor and the second contactor are interlocked. When the coil C1 of the first contactor on the main supply subcircuit is energized, a group of normally closed auxiliary contacts KM12 of the first contactor on the standby subcircuit will be activated and become disconnected. At this time, closing the third switch K3 and the fourth switch K4 will not cause the coil C2 of the second contactor to be energized. Therefore, at this time, the output end mainly outputs the mains power input in the main supply subcircuit, and the standby power supply in the standby subcircuit will enter the hot standby state.

[0072] Furthermore, when an abnormal situation occurs in the AC power input into the main supply sub-circuit, such as a power outage or circuit failure, the main supply sub-circuit will stop inputting AC power, and the coil C1 of the first contactor will lose power, and a group of normally open main contacts KM11 of the first contactor on the main supply sub-circuit will return to the disconnected state, and then the entire main supply sub-circuit will become disconnected, and no current will pass through.

[0073] Furthermore, at this time, a group of normally closed auxiliary contacts KM12 of the first contactor on the standby sub-circuit will also be restored to closure, and the current input by the standby power supply in the standby sub-circuit will energize the coil C2 of the second contactor, thereby causing a group of normally open main contacts KM21 of the second contactor on the standby sub-circuit to actuate and become closed. In other words, the standby sub-circuit becomes conductive, and the output end will output the standby power input in the standby sub-circuit, so that when an abnormal situation occurs in the AC power input, it will automatically switch to the standby power supply in the standby sub-circuit to supply power.

[0074] It should be noted that when the coil C2 of the second contactor on the backup sub-circuit is energized, a set of normally closed auxiliary contacts KM22 of the second contactor on the main supply sub-circuit will become disconnected, which can effectively ensure that the output end will not output both AC power and backup power at the same time, thereby improving the safety of the circuit and ensuring the personal safety of users.

[0075] For details, please refer to Figure 1 , in a possible implementation, the main supply subcircuit is also provided with a set of normally open auxiliary contacts KM23 of the second contactor;

[0076] A group of normally open auxiliary contacts KM23 of the second contactor and a group of normally closed auxiliary contacts KM22 of the second contactor are connected in parallel to connect the other end of the second switch K2 and one pole of the coil C1 of the first contactor.

[0077] It can be understood that by setting a group of normally open auxiliary contacts KM23 of the second contactor in parallel with a group of normally closed auxiliary contacts KM22 of the second contactor in the main supply sub-circuit, when the AC power input in the main supply sub-circuit is abnormal and automatically switches to the backup power input in the backup sub-circuit, the group of normally open auxiliary contacts KM23 of the second contactor on the main supply sub-circuit will become closed. Then, when the AC power input of the main supply sub-circuit returns to normal, the coil C1 of the first contactor can also be energized through the group of normally open auxiliary contacts KM23 of the second contactor in the closed state, thereby restoring the AC power of the main supply sub-circuit to be output through the output end, and suspending the backup power input of the backup sub-circuit, thereby realizing automatic switching and automatic recovery of the power automatic switching circuit.

[0078] For details, please refer to Figure 1 , in a possible implementation, the main supply sub-circuit further includes a first fuse FU1;

[0079] The first fuse FU1 connects the first switch K1 and the second switch K2.

[0080] It is understandable that by providing the first fuse FU1 in the main supply sub-circuit, when the current in the main supply sub-circuit exceeds the rated value, the heat generated will cause the first fuse FU1 to melt, thereby protecting the main supply sub-circuit.

[0081] For details, please refer to Figure 1 , in a possible implementation, the standby sub-circuit further includes a second fuse FU2;

[0082] The second fuse FU2 connects the third switch K3 and the fourth switch K4.

[0083] It is understandable that by setting the first fuse FU2 in the standby sub-circuit, when the current in the standby sub-circuit exceeds the rated value, the heat generated will cause the second fuse FU2 to melt, thereby protecting the main supply sub-circuit.

[0084] Specifically, in a possible implementation, the first switch K1 and the third switch K3 are double-pole single-throw knife switches.

[0085] It can be understood that the double-pole single-throw knife switch combines the circuit configuration of the double-pole single-throw switch and the mechanical operation method of the knife switch. Through its simple and reliable mechanical structure and the ability to control two circuits at the same time, it is very useful in situations where manual control and safe power off are required.

[0086] Specifically, in a possible implementation manner, the second switch K2 and the fourth switch K4 are button switches.

[0087] It is understandable that by setting the second switch K2 and the fourth switch K4 as button switches, it is helpful to quickly synchronize the opening and closing states of the second switch K2 and the fourth switch K4 after closing or opening the first switch K1 and the third switch K3.

[0088] Specifically, in a possible implementation, the present application embodiment also provides a power distribution microgrid system, please refer to Figure 2 , Figure 2 The schematic diagram of the structure of the power distribution microgrid system provided in the embodiment of the present application is shown, and the power distribution microgrid system includes: a mains input terminal, a distribution box, a control module, an inverter charging module, an energy storage module, a new energy power generation input terminal and a new energy power generation controller;

[0089] The distribution box includes a main switch and a distribution box busbar; the control module is provided with an automatic power switching circuit as described in any one of the above;

[0090] The mains input terminal is connected to one end of the main switch;

[0091] The other end of the main switch is connected to the input end of the control module and the inverter charging module;

[0092] The new energy generation input terminal is connected to the new energy generation controller;

[0093] The new energy generation controller is connected to the inverter charging module and the energy storage module;

[0094] The inverter charging module is connected to the input end of the control module;

[0095] The output of the control module is connected to the busbar of the distribution box.

[0096] In the embodiment of the present application, the power distribution microgrid system can be set up in the user's home to regulate the mains system and the new energy power generation system, thereby forming a microgrid system for the user's home. Among them, the microgrid refers to a small-scale power network, which can include energy access terminals, energy storage modules, load terminals, control systems, etc., and can be well applied to application scenarios such as remote areas, industrial parks, urban communities, and emergency power supply, which can effectively improve energy utilization efficiency, enhance the reliability of the distribution system, and reduce pollution to the environment.

[0097] Among them, a distribution box is included, in which a main switch and a distribution box bus are arranged, and the main power access end is connected to the main switch, so the main switch can be used to adjust the opening and closing state of the main power access. The main switch is also connected to the input end of the control module, and the control module is provided with a power automatic switching circuit as described in any of the above, so the connected main power can be connected to the main supply sub-circuit in the power automatic switching circuit as power access. It can be understood that the distribution box bus is connected to multiple load terminals, for example, it can be connected to different types of load terminals such as lighting equipment, air conditioners, outdoor equipment, etc. in the user's home.

[0098] Furthermore, the new energy power generation input terminal is connected to the new energy power generation controller, and the new energy power generation state can be controlled by the new energy power generation controller.

[0099] As an optional embodiment, the new energy power generation input end is provided with any one of a distributed photovoltaic power generation interface, a breeze power generation interface or a small hydropower generation interface.

[0100] That is to say, the user can select any one of distributed solar photovoltaic power generation, breeze power generation or hydropower generation as the new energy power generation method, and connect it to the new energy power generation controller through the new energy power generation input terminal to control the time, operation status, etc. of new energy power generation. By way of example, multiple new energy power generation methods can also be selected for combination. For example, photovoltaic power generation and wind power generation can be selected as new energy power generation methods at the same time.

[0101] Furthermore, the new energy power generation controller is connected to the inverter charging module and the energy storage module, and then connected to the input end of the control module through the inverter charging module, and the output end of the control module is connected to the distribution box bus. In other words, the new energy power generation will be uniformly distributed to the inverter charging module and the energy storage module through the controller. Among them, the energy storage module can use a battery to realize the energy storage of new energy power generation. The inverter charging module is mainly composed of an inverter and a charger, and has a bidirectional function of inverter and charging. It can switch between charging mode and inverter mode according to demand. When in inverter mode, the DC power generated by the new energy power generation can be converted into AC power, and then circulated to the input end of the control module, and can be connected to the standby sub-circuit as a backup power supply; when in charging mode, the mains power connected to the mains input end can be converted into DC power and circulated to the energy storage module, and then the excess mains power can be used to charge the energy storage module.

[0102] Finally, by supplying power to the distribution box busbar through the output end of the control module, the power automatic switching circuit set in the control module can automatically switch the main power connected to the main supply subcircuit and the new energy power generation connected to the standby subcircuit, which can effectively meet the user's grid-connected and off-grid scenario requirements. Among them, the grid-connected type refers to the new energy power generation system being directly connected to the main power, and the off-grid type refers to the independent operation of the new energy power generation system, which uses the control module to coordinate the main power input and the new energy power generation input, and can be compatible with both grid-connected and off-grid power generation scenarios.

[0103] Therefore, by adopting the distribution microgrid system provided in the embodiment of the present application, not only can the advantages of green and safe new energy power generation be better utilized, but also the problem of users' electricity demand being affected by power outages in areas with poor power supply reliability can be solved.

[0104] Specifically, in a possible implementation, the power distribution microgrid system includes a mains power priority operation mode and a renewable energy power generation priority operation mode.

[0105] In an embodiment of the present application, through the control module, the power distribution microgrid system can select a mains power priority operation mode and a new energy power generation priority operation mode.

[0106] It is understandable that in the mains priority operation mode, the control module uses the mains as the input of the main supply sub-circuit to supply power to the distribution box busbar, and can convert the mains into direct current through the inverter charging module to charge the energy storage module when the energy storage module is insufficient. It is understandable that in this operation mode, when the mains input is abnormal, the control module can automatically switch to the backup sub-circuit to supply power, which can be powered by either new energy generation or a combination of new energy generation + energy storage module.

[0107] In the renewable energy power generation priority operation mode, the control module uses renewable energy power generation as the input of the main supply circuit to supply power to the distribution box bus. When the renewable energy power generation can meet the power load, the power load can be supplied by renewable energy power generation, and the excess electric energy can be used to charge the energy storage module. When the renewable energy power generation cannot meet the power load, the electric energy stored in the energy storage module can be used as a supplement.

[0108] Specifically, in a possible implementation, the inverter charging module is connected to the input end of the control module via a power connector.

[0109] In an embodiment of the present application, the input ends of the inverter charging module and the control module are connected through a power connector. For example, an AC 500V dedicated power connector can be selected, and the parameters of the power connector are configured as follows: the operating current is greater than 150A, the operating voltage is greater than 500V, and the maximum withstand voltage is greater than 1500V, which can effectively meet the safe power demand of the maximum load of household electrical equipment.

[0110] It is understandable that the power connector can not only provide a reliable power transmission path, but also reduce the loss during power transmission, ensure efficient energy transfer, improve the reliability of equipment operation, and thus improve the power utilization rate of users' homes.

[0111] Optionally, the power distribution microgrid system provided in the embodiment of the present application can meet the user's usage requirements in different scenarios. For example, the user can choose to apply the power distribution microgrid system provided in the embodiment of the present application to a home power distribution system, a small factory power distribution system, or a small street shop power distribution system.

[0112] For example, when applied to a household power distribution system, batteries of different capacities can be selected as energy storage modules according to user needs, and the energy storage size of the energy storage module can be adjusted by stacking the batteries; when applied to a small factory power distribution system, control modules with different working voltages can be selected to adapt to the factory's industrial electricity needs according to the factory's electricity needs; when applied to a small shop power distribution system, lithium iron phosphate batteries can be selected as batteries for the energy storage modules, which can effectively increase their service life.

[0113] It can be understood that the distribution microgrid system provided in the embodiment of the present application can effectively regulate the input of municipal power and renewable energy power generation. In remote areas or areas with poor power supply stability, it can provide reliable power supply by installing a distribution microgrid system, and can meet the energy storage needs in different application scenarios by independently selecting the number of stacked battery blocks. It has the advantages of effectively improving energy utilization efficiency and enhancing the reliability of the distribution system.

[0114] An automatic power switching circuit and a power distribution microgrid system provided in the embodiments of the present application can interlock two contactors to automatically switch to a backup sub-circuit for power supply when an abnormal condition occurs in a main power sub-circuit, without the need for the user to manually switch the backup power supply, thereby ensuring the user's emergency and security power needs and ensuring the user's safe use of electricity.

[0115] The embodiments described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Those skilled in the art will appreciate that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0116] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0117] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0118] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but the scope of the rights of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present invention should be within the scope of the rights of the present invention.

Claims

1. A power automatic switching circuit, characterized in that: The circuit comprises: a main supply sub-circuit and a standby sub-circuit; The main power supply subcircuit comprises a mains power input terminal, a first switch, a second switch, a first contactor and an output terminal; The standby subcircuit comprises a standby power input terminal, a third switch, a fourth switch, a second contactor and the output terminal; The mains input terminal includes a first phase line input terminal and a first neutral line input terminal, the first switch is a double-pole single-throw switch, and one end of the first switch is connected to the first phase line input terminal and the first neutral line input terminal respectively; The other end of the first switch is connected to the output end through a group of normally open main contacts of the first contactor; One end of the second switch is connected to the other end of the first switch; A set of normally closed auxiliary contacts of the second contactor connects the other end of the second switch and one pole of the coil of the first contactor; The other pole of the coil of the first contactor is connected to the other end of the first switch; The backup power supply input terminal includes a second phase line input terminal and a second neutral line input terminal, the third switch is a double-pole single-throw switch, and one end of the third switch is connected to the second phase line input terminal and the second neutral line input terminal respectively; The other end of the third switch is connected to the output end through a set of normally open main contacts of the second contactor; One end of the fourth switch is connected to the other end of the third switch; A set of normally closed auxiliary contacts of the first contactor is connected to the other end of the fourth switch and one pole of the coil of the second contactor; The other pole of the coil of the second contactor is connected to the other end of the third switch; Before the first switch is closed, the third switch is always kept open.

2. The power automatic switching circuit according to claim 1, characterized in that: The main supply subcircuit is also provided with a set of normally open auxiliary contacts of the second contactor; After a group of normally open auxiliary contacts of the second contactor is connected in parallel with a group of normally closed auxiliary contacts of the second contactor, the other end of the second switch is connected to one pole of the coil of the first contactor.

3. The automatic power switching circuit according to claim 1, characterized in that: The main supply subcircuit also includes a first fuse; The first fuse connects the first switch and the second switch.

4. The automatic power switching circuit according to claim 1, characterized in that: The standby subcircuit also includes a second fuse; The second fuse connects the third switch and the fourth switch.

5. The automatic power switching circuit according to claim 1, characterized in that: The first switch and the third switch are double-pole single-throw knife switches.

6. The automatic power switching circuit according to claim 1, characterized in that: The second switch and the fourth switch are push button switches.

7. A power distribution microgrid system, characterized in that: The system comprises: a mains input terminal, a distribution box, a control module, an inverter charging module, an energy storage module, a new energy power generation input terminal and a new energy power generation controller; The distribution box includes a main switch and a distribution box bus; the control module is provided with an automatic power switching circuit as described in any one of claims 1 to 6; The mains input terminal is connected to one end of the main switch; The other end of the main switch is connected to the input end of the control module and the inverter charging module; The new energy generation input terminal is connected to the new energy generation controller; The new energy power generation controller is connected to the inverter charging module and the energy storage module; The inverter charging module is connected to the input end of the control module; The output end of the control module is connected to the busbar of the distribution box.

8. The power distribution microgrid system according to claim 7, characterized in that: The power distribution microgrid system includes a mains power priority operation mode and a new energy power generation priority operation mode.

9. The power distribution microgrid system according to claim 7, characterized in that: The inverter charging module is connected to the input end of the control module via a power connector.

10. The power distribution microgrid system according to claim 7, characterized in that: The new energy power generation input end is provided with any one of a distributed photovoltaic power generation interface, a breeze power generation interface or a small hydropower generation interface.

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