Redundant network disconnection control system of energy storage inverter

Abstract

The utility model discloses a redundant network disconnection control system of an energy storage inverter. The redundant network disconnection control system comprises more than two access switches which are connected in series between an inverter circuit of the energy storage inverter and a power grid; the number of the drive circuits is consistent with that of the access switches; the main processor is used for outputting a plurality of first control signals; the slave processor is used for outputting a second control signal; the power grid interface voltage sampling circuit is used for sending voltage sampling signals to the master processor and the slave processor; and the number of the gate circuit units is consistent with that of the path switches, and each gate circuit is used for carrying out logic operation on one path of first control signal and the second control signal so as to control the on-off of one path switch. According to the utility model, through the redundant processor and the access switch between the inverter circuit and the power grid, when a device fails, the device can be disconnected from the power grid quickly, and the use safety of the energy storage inverter is ensured.

Description

Technical Field

[0001] The utility model relates to the field of energy storage inverters, in particular to a redundant network disconnection control system of an energy storage inverter. Background Art

[0002] Standards in various countries clearly stipulate that for inverters used for home energy storage, if any device connected to the grid fails, the inverter should be quickly disconnected from the grid to ensure safety. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a redundant disconnection control system for energy storage inverters, which can quickly disconnect from the power grid when the device fails to ensure safe use. The technical solution is as follows:

[0004] A redundant off-grid control system for an energy storage inverter, comprising:

[0005] The number of the pass switches is more than two and they are connected in series between the inverter circuit of the energy storage inverter and the power grid;

[0006] Driving circuits, the number of which is the same as the path switches, for driving the path switches respectively;

[0007] A main processor, configured to output a plurality of first control signals, wherein the number of the first control signals is consistent with the number of the path switches;

[0008] A slave processor is communicatively connected to the master processor and is used to output a second control signal;

[0009] A grid interface voltage sampling circuit, connected to the master processor and the slave processor, and used to send a grid interface voltage sampling signal to the master processor and the slave processor;

[0010] and gate circuit units, each gate circuit unit includes two input terminals and one output terminal, and the output terminal of each gate circuit unit is connected to one of the driving circuits, and is used to perform logical operations on a first control signal and a second control signal to control the on and off of one of the path switches.

[0011] Furthermore, the gate circuit unit is a logic AND unit; the driving circuit is a high voltage drive, when the gate circuit unit outputs a high level, the path switch is controlled to be turned on, and when the gate circuit unit outputs a low level, the path switch is controlled to be turned off.

[0012] Furthermore, the path switch is a relay; when the relay is closed, the path switch is turned on; when the relay is disconnected, the path switch is turned off.

[0013] Furthermore, the driving circuit is an inverting driving circuit, including a transistor, the base of the transistor is connected to the output end of the gate circuit unit, the emitter of the transistor is grounded, the collector of the transistor is electrically connected to one end of the coil of the relay; the other end of the coil is connected to the control power supply.

[0014] Furthermore, the number of the path switches is two.

[0015] Furthermore, the master processor and the slave processor are communicatively connected via a UART interface.

[0016] Furthermore, the master processor and the slave processor are both controllers of the inverter circuit.

[0017] The utility model achieves the following technical effects:

[0018] The redundant disconnection control system of the energy storage inverter of the utility model can quickly disconnect from the power grid when a device fails through redundantly arranged processors and path switches between the inverter circuit and the power grid, thereby ensuring the safe use of the energy storage inverter. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a system block diagram of a redundant off-grid control system of an energy storage inverter of the utility model;

[0020] Figure 2 It is a schematic diagram of the switch and drive circuit of the utility model. DETAILED DESCRIPTION

[0021] To further illustrate each embodiment, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in this field should be able to understand other possible implementations and advantages of the present invention.

[0022] The utility model is now further described in conjunction with the accompanying drawings and specific implementation methods.

[0023] like Figure 1 As shown, an embodiment of a redundant grid-off control system for an energy storage inverter is provided.

[0024] In this embodiment, the battery 100 is connected to the power grid 400 through the inverter circuit 200 of the energy storage inverter. A redundant network disconnection control system 300 is provided between the inverter circuit 200 and the power grid 400, which is used to disconnect the electrical connection between the inverter circuit 200 and the power grid 400 in a timely and reliable manner when an abnormality occurs in the circuit.

[0025] In this embodiment, the redundant grid disconnection control system 300 of the energy storage inverter includes: relays 11 and 12 connected in series between the inverter circuit 200 and the power grid 400 for providing redundant disconnection protection; a main processor 41 and a slave processor 42 for performing redundant fault identification processing; gate circuit units 31 and 32 for performing logical calculations; and drive circuits 21 and 22 for driving the relays 11 and 12, etc.

[0026] In a specific application, the main processor 41 and the slave processor 42 are also controllers of the inverter circuit 200 , which are used to control the AC / DC inversion process between the battery 100 and the power grid 400 .

[0027] The connection relationship is:

[0028] The main processor 41 is provided with two control terminals, which are used to output relay control signals S1 and S2 respectively.

[0029] The slave processor 42 is provided with a control terminal for outputting a relay control signal S3.

[0030] In this embodiment, the gate circuit units 31 and 32 are logic AND units, each including two input terminals and one output terminal. The two input terminals of the gate circuit unit 31 are connected to the main processor 41 and the slave processor 42 respectively, and are used to perform a logic AND operation on the control signal S1 and the control signal S3, and output a signal S13 to control the on and off of the relay 11; the two input terminals of the gate circuit unit 32 are connected to the main processor 41 and the slave processor 42 respectively, and are used to perform a logic AND operation on the control signal S2 and the control signal S3, and output a signal S23 to control the on and off of the relay 12.

[0031] When the energy storage inverter operates normally, the control signal S1 and the control signal S3 are both high level, and the gate circuit unit 31 outputs the signal S13 at a high level. At this time, the drive circuit 21 drives the coil of the relay 11 to operate, and the relay 11 is energized. Similarly, the control signal S2 and the control signal S3 are both high level, and the gate circuit unit 32 outputs the signal S23 at a high level. At this time, the drive circuit 22 drives the coil of the relay 12 to operate, and the relay 12 is energized. When the relays 11 and 12 are energized at the same time, the inverter circuit 200 is connected to the power grid 400.

[0032] When the energy storage inverter operates abnormally, at least one of the main processor 41 and the slave processor 42 detects the abnormality. At this time, the level of at least one of the control signals S1, S2, and S3 is low, and at least one of the signals S13 and S23 is low, driving at least one of the relays 11 and 12 to disconnect, thereby disconnecting the inverter circuit 200 and the power grid 400.

[0033] In this embodiment, the redundant disconnection control system of the energy storage inverter can quickly respond to faults such as abnormal operation of the main processor, abnormal operation of the auxiliary processor, abnormal grid voltage, etc., and disconnect the inverter circuit 200 from the grid 400.

[0034] In this embodiment, two relays 11 and 12 are connected in series between the inverter circuit 200 and the power grid 400, and the main processor 41 uses two signals to control the two relays 11 and 12. When one of the relays fails and sticks, the main processor 41 can also control the other relay to disconnect, ensuring that the inverter circuit 200 can be quickly disconnected from the power grid 400 when the relay fails.

[0035] In this embodiment, the voltage of the grid port is sampled by the voltage sampling circuit and is simultaneously provided to the main processor 41 and the slave processor 42. The two processors can detect the sampled voltage to confirm whether the grid voltage is abnormal. When the grid voltage is abnormal, the main processor 41 can control one or both relays to disconnect, thereby disconnecting the inverter circuit 200 from the grid 400. The slave processor 42 can simultaneously control the two relays to disconnect, thereby disconnecting the inverter circuit 200 from the grid 400.

[0036] In this embodiment, the main processor 41 and the slave processor 42 communicate with each other via UART. The main processor 41 is used to complete the full function control of the inverter circuit 200. Once the system is powered on, the relay control port of the slave processor 42 directly outputs a high level, and the main processor completes all control logics according to the required functions. When the main processor 41 is abnormal or fails, the slave processor 42 can obtain the abnormal information of the main processor 41 through the UART interface. The signal S3 output by the slave processor 42 is a low-level signal. After passing through the gate circuit units 31 and 32, the relays 11 and 12 are driven to disconnect at the same time, and the connection between the inverter circuit 200 and the power grid 400 is quickly disconnected. When the UART communication is abnormal, the energy storage inverter can still work normally, and the slave processor 42 automatically samples the power grid voltage to identify the abnormality of the power grid. When an abnormality occurs in the power grid 400, the slave processor 42 automatically samples the power grid voltage, drives the relays 11 and 12 to disconnect, and cuts off the connection between the inverter circuit 200 and the power grid 400. In summary, when a power grid abnormality or a main processor abnormality occurs, the slave processor 42 can disconnect all relays connected in series between the inverter circuit 200 and the power grid 400 at one time, and quickly disconnect the inverter circuit 200 from the power grid 400 when a fault occurs.

[0037] In practical applications, the number of relays connected in series between the inverter circuit 200 and the power grid 400 may be more than two (including two). Preferably, the number of relays connected in series between the inverter circuit 200 and the power grid 400 is two. To this end, the number of corresponding drive circuits and gate circuit units is two, and the number of relay control terminals set by the main processor is two.

[0038] The path switch between the inverter circuit 200 and the power grid 400 is not limited to a relay. According to different application requirements, the relays 11 and 12 can also be replaced by semiconductor switch tubes such as MOS tubes and IGBTs.

[0039] In this embodiment, the drive circuits 21 and 22 can be used as follows: Figure 2 The inverting drive circuit shown. The inverting drive circuit is composed of transistor Q1, resistors R1, R2, R3, capacitor C1, diode D1, etc. The base of transistor Q1 is connected to the output end of gate circuit unit 31 or 41 through resistors R1, R2; the emitter is grounded; the collector is electrically connected to one end of the coil of the relay through the resistor; the other end of the coil is connected to the power supply +12V. When the base of transistor Q1 inputs a high level, the collector and emitter of transistor Q1 are turned on, current passes through the coil, and the relay is closed.

[0040] The redundant disconnection control system of the energy storage inverter of the utility model has the following technical effects: through redundantly arranged processors and path switches between the inverter circuit and the power grid, it can quickly disconnect from the power grid when a device fails, thereby ensuring the safe use of the energy storage inverter.

[0041] Although the present invention has been specifically demonstrated and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes may be made to the present invention in form and detail without departing from the spirit and scope of the present invention as defined in the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A redundant off-grid control system for an energy storage inverter, characterized in that: include: The number of the pass switches is more than two and they are connected in series between the inverter circuit of the energy storage inverter and the power grid; Driving circuits, the number of which is the same as the path switches, for driving the path switches respectively; A main processor, configured to output a plurality of first control signals, wherein the number of the first control signals is consistent with the number of the path switches; A slave processor is communicatively connected to the master processor and is used to output a second control signal; A grid interface voltage sampling circuit, connected to the master processor and the slave processor, and used to send a grid interface voltage sampling signal to the master processor and the slave processor; and gate circuit units, each gate circuit unit includes two input terminals and one output terminal, and the output terminal of each gate circuit unit is connected to one of the driving circuits, and is used to perform logical operations on a first control signal and a second control signal to control the on and off of one of the path switches.

2. The redundant network disconnection control system of the energy storage inverter according to claim 1, characterized in that: The gate circuit unit is a logic AND unit; the driving circuit is a high voltage drive. When the gate circuit unit outputs a high level, the path switch is controlled to be turned on; when the gate circuit unit outputs a low level, the path switch is controlled to be turned off.

3. The redundant network disconnection control system of the energy storage inverter according to claim 2, characterized in that: The path switch is a relay; when the relay is closed, the path switch is turned on; when the relay is disconnected, the path switch is turned off.

4. The redundant network disconnection control system of the energy storage inverter according to claim 3, characterized in that: The driving circuit is an inverting driving circuit, comprising a transistor, the base of the transistor is connected to the output end of the gate circuit unit, the emitter of the transistor is grounded, the collector of the transistor is electrically connected to one end of the coil of the relay; the other end of the coil is connected to the control power supply.

5. The redundant network disconnection control system of the energy storage inverter according to claim 1, characterized in that: The number of the path switches is two.

6. The redundant network disconnection control system of the energy storage inverter according to claim 1, characterized in that: The master processor and the slave processor communicate with each other via a UART interface.

7. The redundant network disconnection control system of the energy storage inverter according to claim 1, characterized in that: The master processor and the slave processor are both controllers of the inverter circuit.

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