Pre-charging control system and energy storage device

Abstract

The utility model provides a pre-charging control system and an energy storage device, and the pre-charging control system comprises a conversion unit which is used for outputting a power-on control signal; the control unit is used for receiving the power-on control signal and the start operation permission signal output by the first digital quantity output module, and outputting a threshold trigger signal when the received state parameters of the three-phase power supply are preset state parameters; the pre-charging control system does not need to additionally configure control logic, reduces the probability of faults of the pre-charging loop caused by series connection of multiple devices, reduces the hardware cost and the installation complexity, improves the compactness of the pre-charging control system, improves the reliability of the pre-charging control system, and improves the reliability of the pre-charging control system. Space can be utilized to the maximum extent, and later operation and maintenance work is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage devices, in particular to a pre-charge control system and an energy storage device. Background Art

[0002] In the existing technology, small and medium-power general-purpose inverters are generally voltage-type inverters that adopt an AC-DC-AC working mode. When the inverter is just powered on, the filter capacitor on the DC side has a very large capacity. At the moment of charging, it is equivalent to a short circuit for the current, and the current will suddenly change. If no charging resistor is added between the rectifier bridge and the electrolytic capacitor, it is equivalent to a 380V power supply directly short-circuiting to the ground. The rectifier bridge will instantly pass an infinite current, causing the rectifier bridge to explode. Therefore, a pre-charging resistor needs to be connected in series in the charging circuit to limit the current charging at the moment of power-on to protect the rectifier and other input circuit components. After charging is completed, the control circuit mostly short-circuits the resistor through the contacts of the relay, contactor or thyristor to complete the power-on process of the inverter.

[0003] However, the pre-charging control scheme using a combination of frame circuit breakers, contactors and current-limiting resistors often uses a frame circuit breaker for closing at the front end, and pre-charging starts only after closing. After pre-charging, the contacts of the contactor are used to short-circuit the pre-charging resistor. The frame circuit breaker and the contactor are used to sequentially control the pre-charging circuit, which has a high failure rate and poor economy and space utilization. The contactor action time superimposed on the frame circuit breaker is likely to cause opening and closing delays, which may extend the pre-charging cycle and affect the system's rapid grid connection requirements. The contactor can only provide auxiliary contact signals and requires an external PLC (Programmable Logic Controller) or sensor to realize status monitoring. The degree of intelligence is poor. Since the above-mentioned pre-charging control scheme requires additional configuration of control logic, the material cost and installation complexity increase. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art.

[0005] To this end, one purpose of the present invention is to propose a pre-filling control system, which does not require additional configuration of control logic, reduces the probability of failure in the pre-filling circuit caused by multiple devices in series, reduces hardware costs and installation complexity, improves the compactness of the pre-filling control system, can maximize the use of space, and facilitates subsequent operation and maintenance work.

[0006] Therefore, the second purpose of the present invention is to provide an energy storage device.

[0007] In order to achieve the above object, the utility model discloses a first aspect of embodiment of the utility model proposes a precharge control system, the precharge control system includes: conversion unit, the first end and fourth end of conversion unit connect power positive pole, the third end of conversion unit connects power negative pole, for output power -on control signal, control unit, the first input of control unit connects the second end of conversion unit, the second input of control unit connects the first digital output module, for receiving power -on control signal and the first digital output module output's start -up operation permission signal, and when the state parameter of received three -phase power is preset state parameter, output threshold trigger signal, precharge switch unit, the first end and second end of precharge switch unit connect the input of three -phase power, the third end connects the output of three -phase power, the fourth end of precharge switch unit connects auxiliary power output, the fifth end and sixth end of precharge switch unit connect zero line, the serial interface of precharge switch unit connects the serial interface of control unit, for receiving threshold trigger signal, delay switch -on main loop of three -phase power, and shut down precharge loop.

[0008] According to the precharge control system of the utility model embodiment, when the control unit receives the power-on control signal output by the conversion unit and the start-up operation permission signal output by the first digital output module of the PLC, the state parameter is acquired, if the state parameter is the preset state parameter, it is considered that the current state parameter meets the setting requirement of the precharge control system for the three-phase power supply, the threshold trigger signal is output to the precharge switch unit, after the precharge switch unit receives the threshold trigger signal, the internal output circuit breaker closing signal is output, the main loop of the three-phase power supply is switched on in delay according to the circuit breaker closing signal, and the precharge loop is shut down, the utility model does not need to additionally configure the control logic, reduces the probability of precharge loop failure caused by multiple device series connection, reduces the hardware cost and installation complexity, improves the compactness of the precharge control system, can utilize the space to the maximum extent, and facilitates the operation and maintenance work in the later period.

[0009] In some embodiments, the conversion unit comprises: a starting assembly, one end of the starting assembly is connected to the positive pole of the power supply; a first conversion switch, one end of the first conversion switch is connected to the other end of the starting assembly, for conducting the first connection loop between the positive pole of the power supply and the control unit; a first relay, one end of the coil of the first relay is connected to the other end of the first conversion switch, the other end of the coil of the first relay is connected to the negative pole of the power supply, one end of the first contact of the first relay is connected to the positive pole of the power supply, the other end of the first contact of the first relay is connected to one end of the first conversion switch, one end of the second contact of the first relay is connected to the positive pole of the power supply, the other end of the second contact of the first relay is connected to the first input, for outputting the first power-on control signal to the control unit when the first connection loop is conducted.

[0010] In some embodiments, the conversion unit comprises: a second conversion switch for conducting a second connection loop between the positive pole of the power supply and the control unit; a second relay, one end of the coil of the second relay being connected to a second digital output module, the other end of the coil of the second relay being connected to the negative pole of the power supply, one end of the contact of the second relay being connected to the positive pole of the power supply, the other end of the contact of the second relay being connected to one end of the second conversion switch, for outputting a second power-on control signal to the control unit when the second connection loop is conducted.

[0011] In some embodiments, the pre-charging switch unit comprises: an acquisition module connected to the output end of the three-phase power supply for receiving the state parameters and outputting to the control unit; a closing module, the first end and the second end of the closing module being connected to the input end of the three-phase power supply, the third end of the closing module being connected to the output end of the auxiliary power supply, the fourth end and the fifth end of the closing module being connected to the zero line, for receiving the threshold trigger signal, outputting a circuit breaker closing signal, and turning on the main loop after a delay and turning off the pre-charging loop.

[0012] In some embodiments, a contactor, one end of the coil of the contactor being connected to the first control end of the pre-charging switch unit, one end of the contact of the contactor being connected to the input end of the three-phase power supply, the other end of the contact of the contactor being connected to the output end of the three-phase power supply, for conducting or turning off the input end and the output end of the three-phase power supply; a third relay, one end of the coil of the third relay being connected to the second control end of the pre-charging switch unit, the other end of the coil of the third relay being connected to the common end of the pre-charging switch unit, one end of the contact of the third relay being connected to the second control end of the pre-charging switch unit, for receiving the circuit breaker closing signal, the coil of the third relay being energized, and the contact of the third relay being closed after a delay; a first circuit breaker, one end of the first contact of the first circuit breaker being connected to the other end of the coil of the contactor, the other end of the first contact being connected to the common end, one end of the second contact of the first circuit breaker being connected to the input end of the three-phase power supply, the other end of the second contact being connected to the output end of the three-phase power supply, one end of the under-voltage coil of the first circuit breaker being connected to the second control end, the other end of the under-voltage coil being connected to the zero line, one end of the closing coil of the first circuit breaker being connected to the other end of the contact of the third relay, the other end of the closing coil being connected to the zero line, for energizing the closing coil after the under-voltage coil is energized, the second contact turning on the main loop, and the first contact turning off the pre-charging loop of the contactor.

[0013] In some embodiments, the pre-charging switch unit also includes: an auxiliary power supply module, the first end of the auxiliary power supply module is connected to the auxiliary power supply of the pre-charging switch unit, the second end of the auxiliary power supply module is connected to the auxiliary power supply output end, the third end of the auxiliary power supply module is connected to the neutral line, and the fourth end of the auxiliary power supply module is grounded, which is used to turn on or off the output path of the auxiliary power supply.

[0014] In some embodiments, the auxiliary power supply module includes: a switching power supply, a first end of the switching power supply is connected to the auxiliary power supply, a fourth end of the switching power supply is grounded, and is used to convert the auxiliary power supply into a DC power supply; a second circuit breaker, a first end of the second circuit breaker is connected to the second end of the switching power supply, a second end of the second circuit breaker is connected to the auxiliary power supply output end, a third end of the second circuit breaker is connected to the neutral line, and a fourth end of the second circuit breaker is connected to the third end of the switching power supply, and is used to turn on or off the output path of the DC power supply.

[0015] In some embodiments, the pre-charge switch unit further includes: a fuse, wherein the first end and the fourth end of the fuse are connected to the input end of the three-phase power supply, and are used to automatically blow the fuse in the fuse when a three-phase short circuit occurs in the three-phase power supply.

[0016] In some embodiments, the pre-charge switch unit also includes: a first resistor, one end of the first resistor is connected to the second end of the fuse, and the other end of the first resistor is connected to one end of the contact of the contactor; a second resistor, one end of the second resistor is connected to the fourth end of the fuse, and the other end of the second resistor is connected to one end of the contact of the contactor, for receiving the three-phase power supply and reducing the peak amplitude of the three-phase power supply.

[0017] In order to achieve the above-mentioned object, an embodiment of the second aspect of the present utility model provides an energy storage device, which includes the pre-charge control system described in the above-mentioned embodiment.

[0018] According to the energy storage device of the embodiment of the present invention, when the control unit receives the power-on control signal output by the conversion unit and the start-up permission signal output by the first digital output module of the PLC, the state parameter is obtained. If the state parameter is a preset state parameter, it is considered that the current state parameter meets the setting requirements of the pre-charging control system for the three-phase power supply, and a threshold trigger signal is output to the pre-charging switch unit. After the pre-charging switch unit receives the threshold trigger signal, the circuit breaker closing signal is output internally. The main circuit of the three-phase power supply is connected with a delay according to the circuit breaker closing signal, and the pre-charging circuit is turned off. The present invention does not require additional configuration of control logic, reduces the probability of failure of the pre-charging circuit caused by the series connection of multiple devices, reduces hardware costs and installation complexity, improves the compactness of the pre-charging control system, can maximize the use of space, and facilitates subsequent operation and maintenance work.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 This is a hardware structure diagram of a pre-filling control system according to one embodiment of the present utility model;

[0022] Figure 2 It is a structural block diagram of an energy storage device according to an embodiment of the present utility model.

[0023] Reference numerals:

[0024] Pre-fill control system 10;

[0025] Conversion unit 1; control unit 2; pre-charge switch unit 3; acquisition module 4;

[0026] First control terminal 5; second control terminal 6; common terminal 7; auxiliary power supply 8;

[0027] The first digital output module DQ2;

[0028] Starting component SB; first switching switch SW11;

[0029] First relay KA1; coil KA11 of the first relay;

[0030] A second switching switch SW12;

[0031] Second relay KA2; coil KA21 of the second relay; contact KA22 of the second relay;

[0032] The second digital output module DQ1;

[0033] Contactor KM1; contactor coil KM11; contactor contact KM12;

[0034] A third relay KT1; a coil KT11 of the third relay; a contact KT12 of the third relay;

[0035] First circuit breaker QF1; first contact QF11 of the first circuit breaker; second contact QF12 of the first circuit breaker; undervoltage coil MN of the first circuit breaker; closing coil XF of the first circuit breaker;

[0036] Auxiliary power supply module 31;

[0037] Switching power supply UR; second circuit breaker QF2;

[0038] Fusible resistor FU1;

[0039] First resistor R1; second resistor R2;

[0040] Energy storage device 11. DETAILED DESCRIPTION

[0041] The embodiments of the utility model are described in detail below, and the embodiments described with reference to the drawings are exemplary, and the embodiments of the utility model are described in detail below.

[0042] The embodiments of the utility model are described in detail below, and the embodiments described with reference to the drawings are exemplary, and the embodiments of the utility model are described in detail below. Figure 1 The pre-charge control system 10 of the embodiments of the utility model is described.

[0043] As Figure 1 The pre-charge control system 10 of the utility model includes: a conversion unit 1, a control unit 2, a pre-charge switch unit 3, wherein,

[0044] The first end and the fourth end of the conversion unit 1 are connected with the positive pole of the power supply, the third end of the conversion unit 1 is connected with the negative pole of the power supply, for outputting a power-on control signal; the first input end of the control unit 2 is connected with the second end of the conversion unit 1, the second input end of the control unit 2 is connected with the first digital quantity output module DQ2, for receiving the power-on control signal and the start running permission signal outputted by the first digital quantity output module DQ2, and when the state parameter of the three-phase power supply received is the preset state parameter, outputting a threshold trigger signal; the first end and the second end of the pre-charge switch unit 3 are connected with the input end of the three-phase power supply, the third end is connected with the output end of the three-phase power supply, the fourth end of the pre-charge switch unit 3 is connected with the output end L of the auxiliary power supply, the fifth end and the sixth end of the pre-charge switch unit 3 are connected with the zero line N, the serial interface of the pre-charge switch unit 3 is connected with the serial interface of the control unit 2, for receiving the threshold trigger signal, and delaying the connection of the main loop of the three-phase power supply and the shutdown of the pre-charge loop.

[0045] In the embodiments, after the pre-charge starts, the incoming line copper bars L1, L2 and L3 send power, the control unit 2 starts to work after receiving the power-on control signal outputted by the conversion unit 1 and the start running permission signal outputted by the first digital quantity output module DQ2 of the PLC, and it should be noted that the two signals are indispensable, and the pre-charge switch unit 3 starts to acquire the state parameter.

[0046] The serial interface of the control unit 2 and the serial interface of the pre-charging switch unit 3 are connected through the nine-pin serial port X15, and communicate through the RS232 interface protocol to transmit data, namely the status parameters of the three-phase power supply. The control unit 2 and the pre-charging switch unit 3 can both receive signals through the serial port and send signals. When the status parameters are preset status parameters, it is considered that the current status parameters meet the setting requirements of the pre-charging control system 10 for the three-phase power supply, and then a threshold trigger signal is output to the pre-charging switch unit 3. After the pre-charging switch unit 3 receives the threshold trigger signal, it internally outputs a circuit breaker closing signal, and according to the circuit breaker closing signal, the main circuit of the three-phase power supply is connected with a delay, and the pre-charging circuit is turned off.

[0047] According to the pre-charging control system 10 of the embodiment of the present invention, when the control unit 2 receives the power-on control signal output by the conversion unit 1 and the start-up permission signal output by the first digital output module DQ2 of the PLC, it obtains the state parameter. If the state parameter is the preset state parameter, it is considered that the current state parameter meets the setting requirements of the pre-charging control system 10 for the three-phase power supply, and outputs the threshold trigger signal to the pre-charging switch unit 3. After the pre-charging switch unit 3 receives the threshold trigger signal, it internally outputs a circuit breaker closing signal, and delays the connection of the main circuit of the three-phase power supply according to the circuit breaker closing signal, and shuts off the pre-charging circuit. The present invention does not require additional configuration of control logic, reduces the probability of failure of the pre-charging circuit caused by the series connection of multiple devices, reduces hardware costs and installation complexity, improves the compactness of the pre-charging control system 10, can maximize the use of space, and facilitates subsequent operation and maintenance work.

[0048] In some embodiments, as Figure 1 As shown, the conversion unit 1 includes: a starting component such as SB, a first conversion switch such as SW11, and a first relay such as KA1, wherein:

[0049] One end of the starting component SB is connected to the positive pole of the power supply; one end of the first conversion switch SW11 is connected to the other end of the starting component SB, which is used to conduct the first connection loop between the positive pole of the power supply and the control unit 2; one end of the coil KA11 of the first relay KA1 is connected to the other end of the first conversion switch SW11, and the other end of the coil KA11 of the first relay KA1 is connected to the negative pole of the power supply, one end of the first contact KA121 of the first relay KA1 is connected to the positive pole of the power supply, and the other end of the first contact KA121 of the first relay KA1 is connected to one end of the first conversion switch SW11, one end of the second contact KA122 of the first relay KA1 is connected to the positive pole of the power supply, and the other end of the second contact KA122 of the first relay KA1 is connected to the first input end, which is used to output the first power-on control signal to the control unit 2 when the first connection loop is conducted.

[0050] In the embodiment, a suitable conversion unit 1 is selected according to the user's location and the position of the universal conversion switch SW1. When the user is near the position of the universal conversion switch SW1, the starting component SB is manually pressed, and the coil KA11 of the first relay KA1 is energized. Its two normally open contacts KA121 and KA122 are closed, turning on the first connection loop, and outputting the first power-on control signal to the control unit 2, preparing for local power-on.

[0051] In some embodiments, as Figure 1 As shown, the conversion unit 1 includes: a second conversion switch, for example, SW12, and a second relay, for example, KA2, wherein:

[0052] The second conversion switch SW12 is used to turn on the second connection loop between the positive pole of the power supply and the control unit 2; one end of the coil KA21 of the second relay KA2 is connected to the second digital output module DQ1, and the other end of the coil KA21 of the second relay KA2 is connected to the negative pole of the power supply, one end of the contact KA22 of the second relay KA2 is connected to the positive pole of the power supply, and the other end of the contact KA22 of the second relay KA2 is connected to one end of the second conversion switch SW12, which is used to output a second power-on control signal to the control unit 2 when the second connection loop is turned on.

[0053] In the embodiment, a suitable conversion unit 1 is selected according to the user's location and the position of the universal conversion switch SW1. When the user is far away from the location of the universal conversion switch SW1, the second digital output module DQ1 of the PLC sends a remote pre-charge signal, the coil KA21 of the remote power-on relay KA2 is energized, and its normally open contact KA22 is closed, turning on the second connection circuit, and outputting the second power-on control signal to the control unit 2, preparing for remote power-on.

[0054] In some embodiments, as Figure 1 As shown, the pre-charge switch unit 3 includes: a collection module 4 and a closing module (not shown in the figure), wherein:

[0055] The acquisition module 4 is connected to the output end of the three-phase power supply, used to receive status parameters and output them to the control unit 2; the closing module, the first and second ends of the closing module are connected to the input end of the three-phase power supply, the third end of the closing module is connected to the auxiliary power supply output end L, the fourth and fifth ends of the closing module are connected to the neutral line, i.e., the N line, for receiving the threshold trigger signal, outputting the circuit breaker closing signal, delaying the connection of the main circuit, and shutting down the pre-charging circuit.

[0056] In an embodiment, after the acquisition module 4 in the pre-charging switch unit 3 outputs the state parameters of the three-phase power supply to the control unit 2 in real time, if the received state parameters are preset state parameters, it is considered that the current state parameters meet the setting requirements of the pre-charging control system 10 for the three-phase power supply, and then a threshold trigger signal is output to the pre-charging switch unit 3, and then a threshold trigger signal is output to the closing module of the pre-charging switch unit 3; after the closing module in the pre-charging switch unit 3 receives the threshold trigger signal, it internally outputs a circuit breaker closing signal, and delays the main circuit to be connected according to the circuit breaker closing signal, and shuts down the pre-charging circuit.

[0057] Through the built-in voltage and current acquisition module, the status parameters of the three-phase power supply, namely the power parameters, can be monitored in real time, and historical event recording and remote data transmission are supported, which facilitates fault tracing and preventive maintenance, and improves the intelligence of the pre-charging control system 10.

[0058] In some embodiments, as Figure 1 As shown, the closing module includes: a contactor such as KM1, a third relay such as KT1, and a first circuit breaker such as QF1, wherein:

[0059] One end of the coil KM11 of the contactor KM1 is connected to the first control terminal 5 of the pre-charge switch unit 3, one end of the contact KM12 of the contactor KM1 is connected to the input end of the three-phase power supply, and the other end of the contact KM12 of the contactor KM1 is connected to the output end of the three-phase power supply, which is used to turn on or off the input end and output end of the three-phase power supply; one end of the coil KT11 of the third relay KT1 is connected to the second control end 6 of the pre-charge switch unit 3, the other end of the coil KT11 of the third relay KT1 is connected to the common end 7 of the pre-charge switch unit 3, and one end of the contact KT12 of the third relay KT1 is connected to the second control end 6 of the pre-charge switch unit 3, which is used to receive the circuit breaker closing signal, so that the coil KT11 of the third relay KT1 is energized and the contact KT12 of the third relay KT1 is closed with a time delay; one end of the first contact QF11 of the first circuit breaker QF1 is connected to the common end 7 of the pre-charge switch unit 3. The other end of the coil KM11 of the contactor KM1 and the other end of the first contact QF11 of the first circuit breaker QF1 are connected to the common terminal 7, one end of the second contact QF12 of the first circuit breaker QF1 is connected to the input end of the three-phase power supply, the other end of the second contact QF12 of the first circuit breaker QF1 is connected to the output end of the three-phase power supply, one end of the undervoltage coil MN of the first circuit breaker QF1 is connected to the second control terminal 6, the other end of the undervoltage coil MN of the first circuit breaker QF1 is connected to the neutral line, i.e., the N line, one end of the closing coil XF of the first circuit breaker QF1 is connected to the other end of the contact KT12 of the third relay KT1, and the other end of the closing coil XF of the first circuit breaker QF1 is connected to the neutral line, i.e., the N line, so that after the undervoltage coil MN is energized, the closing coil XF delays energization, the second contact QF12 connects the main circuit, and the first contact QF11 shuts off the pre-charge circuit of the contactor KM1.

[0060] In the embodiment, the pre-charging switch unit 3 starts working, and the contactor KM1 in the closing module is powered internally. The contact KM12 of the contactor KM1 is energized and operates, connecting the input and output ends of the three-phase power supply. The acquisition module 4 starts to collect the state parameters of the three-phase power supply, such as the DC bus voltage, and outputs the state parameters, i.e., the DC bus voltage, to the control unit 2 in real time through the serial interface. After the control unit 2 receives the state parameters, if the received state parameters are the preset state parameters, it is considered that the current state parameters meet the setting requirements of the pre-charging control system 10 for the three-phase power supply, and when the power-on control signal output by the conversion unit 1 and the start-up permission signal output by the first digital output module DQ2 are received, a threshold trigger signal is output to the closing module of the pre-charging switch unit 3.

[0061] After the closing module in the pre-charging switch unit 3 receives the threshold trigger signal, the pre-charging switch unit 3 internally supplies power to the third relay KT1, and the second control terminal 6 connected to the coil KT11 of the third relay KT1 is the main circuit breaker closing port. The main circuit breaker closing port outputs the circuit breaker closing signal, and the coil KT11 of the third relay KT1 is energized and works. At this time, the undervoltage coil MN of the first circuit breaker QF1 is energized; after the set time, the contact KT12 of the third relay KT1 is actuated, and the closing coil XF of the first circuit breaker QF1 is energized, and the first circuit breaker QF 1 is successfully closed and energized in sections to prevent the two coils from being energized at the same time, which would result in a failure to close the circuit smoothly. After the first circuit breaker QF1 is successfully closed, the second contact QF12 of the first circuit breaker QF1 is closed, connecting the input and output ends of the three-phase power supply, and realizing delayed connection of the main circuit; at the same time, the normally closed contact of the first circuit breaker QF1, i.e. the first contact QF11, is used to disconnect the coil KM11 of the contactor KM1. The contact KM12 of the contactor KM1 is also disconnected due to the disconnection of the coil KM11, causing the contactor KM1 to lose power, realizing delayed shutdown of the pre-charging circuit, and ending the pre-charging.

[0062] In some embodiments, as Figure 1 As shown, the pre-charging switch unit 3 also includes: an auxiliary power supply module 31, wherein the first end of the auxiliary power supply module 31 is connected to the auxiliary power supply 8 of the pre-charging switch unit 3, the second end of the auxiliary power supply module 31 is connected to the auxiliary power supply output end L, the third end of the auxiliary power supply module 31 is connected to the neutral line, i.e., the N line, and the fourth end of the auxiliary power supply module 31 is grounded, which is used to turn on or off the output path of the auxiliary power supply 8.

[0063] In some embodiments, as Figure 1 As shown, the auxiliary power supply module 31 includes: a switching power supply UR, a second circuit breaker QF2, wherein,

[0064] A first end of the switching power supply UR is connected to the auxiliary power supply 8, and a fourth end of the switching power supply UR is grounded, for converting the auxiliary power supply 8 into a DC power supply; a first end of the second circuit breaker QF2 is connected to a second end of the switching power supply UR, a second end of the second circuit breaker QF2 is connected to the auxiliary power supply output terminal L, a third end of the second circuit breaker QF2 is connected to the neutral line, i.e., the N line, and a fourth end of the second circuit breaker QF2 is connected to the third end of the switching power supply UR, for turning on or off the output path of the DC power supply.

[0065] In the embodiment, the function of the switching power supply UR is to convert the auxiliary power supply 8 into the DC power required by the user. The input of the switching power supply UR is usually an AC power supply or a DC power supply, and the output is a device that requires a DC power supply, such as a personal computer.

[0066] After precharging starts, the second circuit breaker QF2 is closed first so that the precharging switch unit 3 starts working, and its internal power is supplied to the contactor KM1 in the closing module. The precharging contactor KM1 is energized and runs, and the acquisition module 4 starts to collect the DC bus voltage.

[0067] In some embodiments, as Figure 1 As shown, the pre-charge switch unit 3 also includes: a fuse FU1, wherein the first end and the fourth end of the fuse FU1 are connected to the input end of the three-phase power supply, and are used to automatically blow the fuse in the fuse FU1 when a three-phase short circuit occurs in the three-phase power supply, thereby disconnecting the circuit.

[0068] In some embodiments, as Figure 1 As shown, the pre-charge switch unit 3 further includes: a first resistor, for example, denoted as R1, and a second resistor, for example, denoted as R2, wherein:

[0069] One end of the first resistor R1 is connected to the second end of the fuse FU1, and the other end of the first resistor R1 is connected to one end of the contact KM12 of the contactor KM1; one end of the second resistor R2 is connected to the fourth end of the fuse FU1, and the other end of the second resistor R2 is connected to one end of the contact KM12 of the contactor KM1, which is used to receive three-phase power supply and reduce the peak amplitude of the three-phase power supply, wherein the first resistor R1 and the second resistor R2 can be set to 1kW, 2.1Ω resistance.

[0070] The structure of a single main frame circuit breaker reduces loop nodes, reduces the probability of pre-charging circuit failure caused by multiple devices in series, reduces hardware costs and installation complexity, improves the compactness of the pre-charging control system 10, can maximize the use of space, and facilitate subsequent operation and maintenance work; by canceling the front-end frame circuit breaker and using the main frame circuit breaker to replace the contactor, the protection capability and breaking capacity of the circuit can be improved, and the protection curve can be dynamically adjusted to match different fluctuating load characteristics.

[0071] The pre-charge control system 10 has a built-in magnetic blow-out arc chamber and metal grid, which can cut off short-circuit currents above 100kA, reduce the risk of contact ablation, and adjust the protection curve in real time through a programmable trip unit to match the fluctuating load characteristics of the wind / solar energy storage system.

[0072] The key components of the main frame circuit breaker, namely the first circuit breaker QF1, adopt a modular structure, support hot-swappable replacement of trip units and communication modules, shorten fault repair time, facilitate subsequent operation and maintenance, and have low operation and maintenance costs; the pre-charge control system 10 supports Modbus / TCP protocol to interact with the SCADA system, realizing millisecond-level synchronization of frequency modulation instructions and circuit breaker actions.

[0073] According to the pre-charging control system 10 of the embodiment of the present invention, when the control unit 2 receives the power-on control signal output by the conversion unit 1 and the start-up permission signal output by the first digital output module DQ2 of the PLC, it obtains the state parameter. If the state parameter is the preset state parameter, it is considered that the current state parameter meets the setting requirements of the pre-charging control system 10 for the three-phase power supply, and outputs the threshold trigger signal to the pre-charging switch unit 3. After the pre-charging switch unit 3 receives the threshold trigger signal, it internally outputs a circuit breaker closing signal, and delays the connection of the main circuit of the three-phase power supply according to the circuit breaker closing signal, and shuts off the pre-charging circuit. The present invention does not require additional configuration of control logic, reduces the probability of failure of the pre-charging circuit caused by the series connection of multiple devices, reduces hardware costs and installation complexity, improves the compactness of the pre-charging control system 10, can maximize the use of space, and facilitates subsequent operation and maintenance work.

[0074] The following combination Figure 2 The energy storage device 11 of the present invention is described.

[0075] like Figure 2 As shown, the energy storage device 11 of the embodiment of the present utility model includes the pre-charge control system 10 of the above embodiment.

[0076] According to the energy storage device 11 of the embodiment of the present invention, when the control unit 2 receives the power-on control signal output by the conversion unit 1 and the start-up permission signal output by the first digital output module DQ2 of the PLC, the state parameter is obtained. If the state parameter is a preset state parameter, it is considered that the current state parameter meets the setting requirements of the pre-charging control system 10 for the three-phase power supply, and a threshold trigger signal is output to the pre-charging switch unit 3. After the pre-charging switch unit 3 receives the threshold trigger signal, the circuit breaker closing signal is output internally. According to the circuit breaker closing signal, the main circuit of the three-phase power supply is connected with a delay, and the pre-charging circuit is turned off. The present invention does not require additional configuration of control logic, reduces the probability of failure of the pre-charging circuit caused by the series connection of multiple devices, reduces hardware costs and installation complexity, improves the compactness of the pre-charging control system 10, can maximize the use of space, and facilitates subsequent operation and maintenance work.

[0077] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily mean the same embodiment or example.

[0078] Although the embodiments of the present application have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A pre-filling control system, characterized in that: include: a conversion unit, wherein the first and fourth terminals of the conversion unit are connected to the positive electrode of the power supply, and the third terminal of the conversion unit is connected to the negative electrode of the power supply, and is used to output a power-on control signal; a control unit, wherein a first input end of the control unit is connected to the second end of the conversion unit, and a second input end of the control unit is connected to the first digital output module, and is configured to receive the power-on control signal and the start-up operation permission signal output by the first digital output module, and output a threshold trigger signal when the received state parameter of the three-phase power supply is a preset state parameter; A pre-charging switch unit, wherein the first and second ends of the pre-charging switch unit are connected to the input end of the three-phase power supply, the third end is connected to the output end of the three-phase power supply, the fourth end of the pre-charging switch unit is connected to the auxiliary power supply output end, the fifth and sixth ends of the pre-charging switch unit are connected to the neutral line, and the serial interface of the pre-charging switch unit is connected to the serial interface of the control unit, and is used to delay the connection of the main circuit of the three-phase power supply and shut down the pre-charging circuit when receiving a threshold trigger signal.

2. The pre-fill control system according to claim 1, characterized in that: The conversion unit includes: A starting component, one end of which is connected to the positive electrode of the power supply; a first transfer switch, one end of which is connected to the other end of the starting component, and is used to conduct a first connection loop between the positive electrode of the power supply and the control unit; A first relay, one end of the coil of the first relay is connected to the other end of the first conversion switch, the other end of the coil of the first relay is connected to the negative electrode of the power supply, one end of the first contact of the first relay is connected to the positive electrode of the power supply, the other end of the first contact of the first relay is connected to one end of the first conversion switch, one end of the second contact of the first relay is connected to the positive electrode of the power supply, and the other end of the second contact of the first relay is connected to the first input end, for outputting a first power-on control signal to the control unit when the first connection loop is turned on.

3. The pre-fill control system according to claim 1, characterized in that: The conversion unit includes: a second conversion switch, configured to conduct a second connection loop between the positive electrode of the power supply and the control unit; A second relay, one end of the coil of the second relay is connected to the second digital output module, the other end of the coil of the second relay is connected to the negative pole of the power supply, one end of the contact of the second relay is connected to the positive pole of the power supply, and the other end of the contact of the second relay is connected to one end of the second conversion switch, for outputting a second power-on control signal to the control unit when the second connection circuit is turned on.

4. The pre-fill control system according to claim 1, characterized in that: The pre-charge switch unit includes: an acquisition module connected to the output end of the three-phase power supply, configured to receive the state parameter and output it to the control unit; A closing module, wherein the first and second ends of the closing module are connected to the input end of the three-phase power supply, the third end of the closing module is connected to the output end of the auxiliary power supply, and the fourth and fifth ends of the closing module are connected to the neutral line, and are used to receive the threshold trigger signal, output a circuit breaker closing signal, delay the connection of the main circuit, and shut down the pre-charging circuit.

5. The pre-fill control system according to claim 4, characterized in that: The closing module includes: A contactor, wherein one end of the coil of the contactor is connected to the first control end of the pre-charge switch unit, one end of the contact of the contactor is connected to the input end of the three-phase power supply, and the other end of the contact of the contactor is connected to the output end of the three-phase power supply, and is used to turn on or off the input end and the output end of the three-phase power supply; a third relay, wherein one end of the coil of the third relay is connected to the second control end of the pre-charging switch unit, the other end of the coil of the third relay is connected to the common end of the pre-charging switch unit, and one end of the contact of the third relay is connected to the second control end of the pre-charging switch unit, and is configured to energize the coil of the third relay and delay closing of the contact of the third relay when receiving the circuit breaker closing signal; A first circuit breaker, one end of the first contact of the first circuit breaker is connected to the other end of the coil of the contactor, the other end of the first contact is connected to the common end, one end of the second contact of the first circuit breaker is connected to the input end of the three-phase power supply, the other end of the second contact is connected to the output end of the three-phase power supply, one end of the undervoltage coil of the first circuit breaker is connected to the second control end, the other end of the undervoltage coil is connected to the neutral wire, one end of the closing coil of the first circuit breaker is connected to the other end of the contact of the third relay, the other end of the closing coil is connected to the neutral wire, and after the undervoltage coil is energized, the closing coil is delayed to be energized, the second contact connects the main circuit, and the first contact shuts off the pre-charge circuit of the contactor.

6. The pre-fill control system according to claim 5, characterized in that: The pre-charge switch unit further includes: An auxiliary power supply module, wherein the first end of the auxiliary power supply module is connected to the auxiliary power supply of the pre-charging switch unit, the second end of the auxiliary power supply module is connected to the auxiliary power supply output end, the third end of the auxiliary power supply module is connected to the neutral line, and the fourth end of the auxiliary power supply module is grounded, and is used to turn on or off the output path of the auxiliary power supply.

7. The pre-fill control system according to claim 6, characterized in that: The auxiliary power supply module includes: a switching power supply, wherein a first terminal of the switching power supply is connected to the auxiliary power supply, a fourth terminal of the switching power supply is grounded, and is configured to convert the auxiliary power supply into a DC power supply; A second circuit breaker, wherein the first end of the second circuit breaker is connected to the second end of the switching power supply, the second end of the second circuit breaker is connected to the auxiliary power supply output end, the third end of the second circuit breaker is connected to the neutral line, and the fourth end of the second circuit breaker is connected to the third end of the switching power supply, and is used to turn on or off the output path of the DC power supply.

8. The pre-fill control system according to claim 6, characterized in that: The pre-charge switch unit further includes: A fuse, wherein the first end and the fourth end of the fuse are connected to the input end of the three-phase power supply, and is used for automatically melting the fuse element in the fuse when a three-phase short circuit occurs in the three-phase power supply.

9. The pre-fill control system according to claim 8, characterized in that: The pre-charge switch unit further includes: a first resistor, one end of the first resistor being connected to the second end of the fuse, and the other end of the first resistor being connected to one end of the contact of the contactor; A second resistor, one end of which is connected to the fourth end of the fuse, and the other end of which is connected to one end of the contact of the contactor, is used to receive the three-phase power supply and reduce the peak amplitude of the three-phase power supply.

10. An energy storage device, characterized in that: include: A pre-fill control system according to any one of claims 1 to 9.

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