Test circuit

Abstract

The utility model discloses a test circuit, which relates to the field of circuits, and is provided with a plurality of test loops which are connected with a plurality of PCS modules in a one-to-one correspondence manner, and sampling modules in the test loops are connected to alternating current sides of the PCS modules, so that a control module can determine whether the PCS modules are abnormal or not according to received output conditions of the alternating current sides of the PCS modules. Therefore, the testing process of the single PCS module corresponding to each sampling module is realized, and effective function and performance testing is directly carried out on the PCS module by utilizing the testing loop, so that semi-finished products with potential quality hazards can be comprehensively screened out; the influence of abnormal modules on the production debugging process of the whole machine in the later test process of the whole machine of the high-voltage cascade energy storage system is avoided, the independent test process of a plurality of PCS modules can be realized in one test process, the working efficiency of the whole test process is improved, the time is saved, and the test efficiency is improved. And rapid realization of the whole machine test process of the whole high-voltage cascade energy storage system is facilitated.

Description

Technical Field

[0001] The utility model relates to the field of circuits, in particular to a testing circuit. Background Art

[0002] At present, high-voltage cascade energy storage systems are usually implemented by PCS (Power Convers ion System, energy storage converter) module series connection technology. According to the different voltage levels of the access grid, the number of PCS modules in series is different. The higher the voltage, the more PCS modules are used. With the continuous development of energy storage systems, users have higher and higher requirements for the safety and reliability of high-voltage cascade energy storage systems. In the existing technology, after the entire high-voltage cascade energy storage system is built using PCS modules, the entire high-voltage cascade energy storage system is usually tested. The safety and reliability of the PCS module and the entire high-voltage cascade energy storage system are tested through the whole machine testing process. However, this method cannot test a single PCS module. Once there is an abnormality in the PCS module, it will cause an abnormality in the debugging process of the whole machine, and even the abnormal PCS module needs to be disassembled again for troubleshooting. This leads to low efficiency in the whole machine testing process of the high-voltage cascade energy storage system, which is not conducive to the rapid implementation of the production debugging process of the whole machine. Utility Model Content

[0003] The purpose of the utility model is to provide a test circuit, which utilizes the sampling module in the test loop to directly perform effective function and performance tests on the PCS module, can comprehensively screen out semi-finished products with quality risks, and avoid abnormal modules affecting the production and debugging process of the whole machine during the later whole machine testing process of the high-voltage cascade energy storage system, and one test process can realize independent test processes for multiple PCS modules, thereby improving the work efficiency of the entire test process, saving time, and being conducive to the rapid realization of the whole machine testing process of the entire high-voltage cascade energy storage system.

[0004] In order to solve the above technical problems, the utility model provides a test circuit, including a power supply module, a control module, a plurality of PCS modules and a plurality of test loops connected to the plurality of PCS modules in a one-to-one correspondence, wherein the test loop includes a power supply switch, a control switch, a rectifier module, a sampling module and a load;

[0005] For any of the test loops, the first end of the power switch is connected to the output end of the power supply module, the second end is connected to the first end of the control switch, the second end of the control switch is connected to the output end of the rectifier module, the output end of the rectifier module is connected to the DC side of the PCS module, the input end of the sampling module is connected in series with the load, and the two ends of the series-connected circuit are connected to the AC side of the PCS module, the output end of the sampling module is connected to the input end of the control module, and the output end of the control module is connected to the control end of the PCS module;

[0006] The sampling module is used to sample the output of the AC side of the PCS module so that the control module can complete the test process of the PCS module.

[0007] Optionally, the PCS module includes a first switch tube, a second switch tube, a third switch tube, a fourth switch tube and several capacitors connected in parallel, the first switch tube and the second switch tube are connected in series, and the two ends of the series circuit are respectively connected to the two ends of the circuit after the capacitors are connected in parallel, the third switch tube and the fourth switch tube are connected in series, and the two ends of the series circuit are respectively connected to the two ends of the circuit after the capacitors are connected in parallel, the control end of the first switch tube, the control end of the second switch tube, the control end of the third switch tube, and the control end of the fourth switch tube are all connected to the output end of the control module, the two ends of the circuit after the several capacitors are connected in parallel serve as the DC side of the PCS module, the series midpoint of the first switch tube and the second switch tube serves as the first end of the AC side of the PCS module, and the series midpoint of the third switch tube and the fourth switch tube serves as the second end of the AC side of the PCS module.

[0008] Optionally, the rectifier module is a three-phase uncontrolled rectifier bridge;

[0009] Correspondingly, the power supply switch includes three power supply sub-switches, and the control switch includes three control sub-switches. The first ends of the three power supply sub-switches are connected one-to-one with the three phase lines of the power supply module, the second ends of the power supply sub-switches are connected one-to-one with the first ends of the control sub-switches, and the second ends of the three control sub-switches are connected one-to-one with the three input ends of the three-phase uncontrolled rectifier bridge.

[0010] Optionally, the sampling module and the control module are connected via an optical fiber.

[0011] Optionally, the control module includes a power module and a main controller including a main control board, a sampling board, and a fiber optic board. The output end of the power module is connected to the power port of the main controller, the input end of the sampling board is connected to the output end of the sampling module, the output end is connected to the input end of the main control board, the output end of the main control board is connected to the input end of the fiber optic board, and the output end of the fiber optic board is connected to the control end of the PCS module.

[0012] Optionally, the power module includes a main power supply, a backup power supply and a dual power supply circuit board, and the output end of the main power supply and the output end of the backup power supply are both connected to the power port of the main controller through the dual power supply circuit board.

[0013] Optionally, the control module further includes a human-machine interface, a power port of the human-machine interface is connected to a power port of the main controller, and a communication port is connected to the main control board.

[0014] Optionally, the load is an air-core reactor.

[0015] Optionally, the power supply module includes a circuit breaker and a voltage regulator, a first end of the circuit breaker is connected to the power supply, a second end is connected to the input end of the voltage regulator, and an output end of the voltage regulator serves as an output end of the power supply module;

[0016] The voltage regulator is used to adjust the output voltage output to the test loop.

[0017] Optionally, the sampling module is a current sensor.

[0018] The utility model provides a test circuit, comprising a power supply module, a control module, a plurality of PCS modules and a plurality of test loops connected to the plurality of PCS modules in a one-to-one correspondence, wherein the test loop comprises a power supply switch, a control switch, a rectifier module, a sampling module and a load, the sampling module connected to the AC side of the PCS module can detect the output condition of the AC side of the PCS module, and the sampling module is also connected to the control module, and the control module can determine whether the PCS module has an abnormality according to the output condition of the AC side of the received PCS module, thereby realizing the test process of a single PCS module corresponding to each sampling module, and directly performing effective function and performance tests on the PCS module by using the test loop, which can comprehensively screen out semi-finished products with quality risks, and avoid the occurrence of abnormal modules in the whole machine test process of the high-voltage cascade energy storage system in the later stage to affect the production and debugging process of the whole machine, and one test process can realize the independent test process of multiple PCS modules, thereby improving the work efficiency of the whole test process, saving time, and being conducive to the rapid realization of the whole machine test process of the whole high-voltage cascade energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 A structural schematic diagram of a test circuit provided by the utility model;

[0021] Figure 2 A structural schematic diagram of another test circuit provided by the utility model;

[0022] Figure 3 The present invention provides a structural diagram of a control module. DETAILED DESCRIPTION

[0023] The core of the utility model is to provide a test circuit, which uses the sampling module in the test loop to directly perform effective function and performance tests on the PCS module, and can comprehensively screen out semi-finished products with quality risks, avoiding the occurrence of abnormal modules in the later whole-machine testing process of the high-voltage cascade energy storage system that affects the production and debugging process of the whole machine, and one test process can realize the independent test process of multiple PCS modules, thereby improving the work efficiency of the entire test process, saving time, and facilitating the rapid realization of the whole-machine testing process of the entire high-voltage cascade energy storage system.

[0024] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a test circuit provided by the utility model; please refer to Figure 2 , Figure 2 This is a structural diagram of another test circuit provided by the utility model; please refer to Figure 3 , Figure 3A structural diagram of a control module provided by the utility model. To solve the above technical problems, the utility model provides a test circuit, including a power supply module 1, a control module, a plurality of PCS modules 3 and a plurality of test loops connected to the plurality of PCS modules 3 in a one-to-one correspondence, the test loop including a power supply switch QF1, a control switch KM1, a rectifier module 2, a sampling module 4 and a load 6;

[0026] For any test loop, the first end of the power switch QF1 is connected to the output end of the power supply module 1, the second end is connected to the first end of the control switch KM1, the second end of the control switch KM1 is connected to the output end of the rectifier module 2, the output end of the rectifier module 2 is connected to the DC side of the PCS module 3, the input end of the sampling module 4 is connected in series with the load 6, and the two ends of the series-connected circuit are connected to the AC side of the PCS module 3, the output end of the sampling module 4 is connected to the input end of the control module, and the output end of the control module is connected to the control end of the PCS module 3;

[0027] The sampling module 4 is used to sample the output of the AC side of the PCS module 3 so that the control module can complete the test process of the PCS module 3 .

[0028] Taking into account that in the prior art, directly debugging the high-voltage cascade energy storage system without testing the PCS module 3 will lead to low efficiency in the debugging of the whole machine, the present application provides a test circuit. By using this test circuit, effective function and performance tests are performed on a single PCS module 3 in advance during the production and manufacturing of the PCS module 3, so as to avoid abnormal modules appearing in the later whole machine testing process and affecting the production and debugging process of the whole machine. At the same time, considering that the power supply needs to be driven on the DC side of the PCS module 3 during the test process in order to carry out the load test process of the PCS module 3, a power supply module 1, a power switch QF1, a control switch KM1 and a rectifier module 2 connected in sequence are set in the test loop, the output end of the rectifier module 2 is connected to the DC side of the PCS module 3, the power supply module 1 is used to power the DC side of the PCS module 3, and the load 6 is connected to the AC side of the PCS module 3, so as to realize the simulation of the load working process of the PCS module 3. At the same time, considering that the test circuit is mainly used as a full voltage, full current, and full power test device for the PCS module 3 in the high-voltage cascade energy storage system, it is necessary to detect the output of the voltage, current or power of the PCS module 3 in real time, so a sampling module 4 is also set on the AC side of the PCS module 3 to sample the output of the AC side of the PCS module 3. After receiving the sampling result of the sampling module 4, the control module can determine the working condition of the PCS module 3 according to the sampling result, so as to judge whether the PCS module 3 can meet the output requirements of full voltage, full current, and full power and whether it can work normally.

[0029] Specifically, when a certain PCS module 3 needs to be tested, the power supply switch QF1 and the control switch KM1 are closed, so that the voltage output by the power supply module 1 can output DC power to the DC side of the PCS module 3 after rectification by the rectifier module 2. The DC power drives the PCS module 3 to start working and output voltage and current from the AC side. At this time, the voltage and / or current output by the PCS module 3 are sampled by the sampling module 4, and based on the voltage output by the power supply module 1, it is judged whether the voltage and / or current output by the AC side of the PCS module 3 is within the normal working range. In particular, the power supply module 1 can be controlled to output a power supply voltage that enables the PCS module 3 to enter the full voltage, full current, and full power working state, and then the control module judges whether the PCS module 3 can output full voltage, full current, and full power normally according to the sampling result of the sampling module 4.

[0030] As a specific embodiment, Figure 2 As shown, in order to improve the efficiency of the test, a method is adopted in which at most n PCS modules 3 can be tested at full power at one time. Each PCS module 3 is provided with an independent test circuit. Each test circuit is mainly composed of the protective disconnecting molded case switch of the AC circuit as the power supply switch QF1, the opening and closing control contactor switch as the control switch KM1, the rectifier module 2, the PCS module 3 under test, the AC load 6 reactance and the current sensor as the circuit detection and control auxiliary circuit. And the AC power supply of the n circuits is uniformly regulated by a 30kVA voltage regulator T0, and the voltage is adjusted within a certain range. The input side of the voltage regulator T0 is connected to the power supply through the AC 400V protection circuit breaker QF0 switch. At the same time, Figure 3 As shown, a main controller 51 is set as a control module in the control cabinet of the high-voltage cascade energy storage system, and the sampling results of the sampling module 4 and the control process of the PCS module 3 are received through the main control board, sampling board, and optical fiber board set on the circuit board.

[0031] It is not difficult to understand that the present application provides a test method for power modules in a high-voltage cascade energy storage system, and the control module of the entire test circuit can be directly implemented using the control cabinet of the high-voltage cascade energy storage system itself, and some existing product components can be used to perform full-voltage, full-current, and full-power tests on the PCS module 3. The entire test process can comprehensively screen out PCS module semi-finished products with quality risks, avoiding failures during the whole machine load test and affecting the delivery schedule. At the same time, according to the number of modules that need to be tested, multiple PCS modules 3 can be flexibly selected for full-load and overload testing at the same time, and no personnel are required to be on duty during the test.

[0032] It should be noted that the present application does not specifically limit the specific types and implementation methods of the power supply module 1, the control module, the PCS module 3, the power supply switch QF1, the control switch KM1, the rectifier module 2, the sampling module 4 and the load 6 in the test circuit, and can be selected and adjusted according to actual needs; the power supply module 1 can be directly implemented with three-phase alternating current, the control module can be directly implemented using the control system in the control cabinet of the high-voltage cascade energy storage system itself, or a control system dedicated to the test circuit can be additionally set up, the power supply switch QF1 can be implemented with switching devices such as circuit breakers to control whether the power supply module 1 supplies power to this test circuit, the control switch KM1 can be implemented with control devices such as contactors to control whether the corresponding test circuit starts testing, the rectifier module 2 can be implemented in the form of a rectifier, etc., the sampling module 4 can be implemented with detection devices such as sensors, and the load 6 can be determined according to the actual application of the PCS module 3.

[0033] The utility model provides a test circuit, comprising a power supply module 1, a control module, a plurality of PCS modules 3 and a plurality of test loops connected to the plurality of PCS modules 3 in a one-to-one correspondence, wherein the test loop comprises a power supply switch QF1, a control switch KM1, a rectifier module 2, a sampling module 4 and a load 6, the sampling module 4 connected to the AC side of the PCS module 3 can detect the output condition of the AC side of the PCS module 3, and the sampling module 4 is also connected to the control module, and the control module can determine whether the PCS module 3 is abnormal according to the received output condition of the AC side of the PCS module 3, thereby realizing the test process of the single PCS module 3 corresponding to each sampling module 4, and directly performing effective function and performance tests on the PCS module 3 by using the test loop, and can comprehensively screen out semi-finished products with quality risks, and avoid the occurrence of abnormal modules in the whole machine test process of the high-voltage cascade energy storage system in the later stage to affect the production and debugging process of the whole machine, and one test process can realize the independent test process of multiple PCS modules 3, thereby improving the work efficiency of the whole test process, saving time, and being conducive to the rapid realization of the whole machine test process of the whole high-voltage cascade energy storage system.

[0034] Based on the above embodiments:

[0035] As an optional embodiment, the PCS module 3 includes a first switch tube, a second switch tube, a third switch tube, a fourth switch tube and several capacitors C connected in parallel. The first switch tube and the second switch tube are connected in series, and the two ends of the circuit after the series connection are respectively connected to the two ends of the circuit after the capacitor C is connected in parallel. The third switch tube and the fourth switch tube are connected in series, and the two ends of the circuit after the series connection are respectively connected to the two ends of the circuit after the capacitor C is connected in parallel. The control end of the first switch tube, the control end of the second switch tube, the control end of the third switch tube, and the control end of the fourth switch tube are all connected to the output end of the control module. The two ends of the circuit after the several capacitors C are connected in parallel serve as the DC side of the PCS module 3, the series midpoint of the first switch tube and the second switch tube serves as the first end of the AC side of the PCS module 3, and the series midpoint of the third switch tube and the fourth switch tube serves as the second end of the AC side of the PCS module 3.

[0036] It is not difficult to understand that the PCS module 3 in the high-voltage cascade energy storage system is generally implemented in the form of an H full bridge, which is divided into a left half bridge and a right half bridge. Each half bridge uses a double-tube IGBT (Insulated Gate Bipolar Transistor). Figure 2 As shown, the left half bridge is realized by the first switch tube and the second switch tube connected in series, and the right half bridge is realized by the third switch tube and the fourth switch tube connected in series. The two ends of the first switch tube and the second switch tube connected in series are connected to the DC side of the PCS module 3, and the midpoint of the first switch tube and the second switch tube connected in series is connected to the AC side of the PCS module 3. The two ends of the third switch tube and the fourth switch tube connected in series are connected to the DC side of the PCS module 3, and the midpoint of the third switch tube and the fourth switch tube connected in series is connected to the AC side of the PCS module 3. In addition, a plurality of large-capacity DC film capacitors C are arranged in parallel at both ends of the DC side (DC+ and DC-) to filter and stabilize the DC voltage when the battery pack is not connected to the bus. The specific types and implementation methods of the first switch tube, the second switch tube, the third switch tube, the fourth switch tube and the capacitor C are not particularly limited in this application. Figure 2 As shown, for the nth test loop, that is, loop n, the first switch tube is Q1_n, the second switch tube is Q2_n, the third switch tube is Q3_n, the fourth switch tube is Q4_n, the fifth switch tube is Q5_n, and the sixth switch tube is Q6_n.

[0037] Specifically, the PCS module 3 in the high-voltage cascade energy storage system is generally implemented in the form of an H full bridge. The entire circuit structure is simple and easy to implement, and can effectively realize the current conversion function of the PCS module 3. The components used are low-cost and small in size, which is conducive to the simple implementation of the entire PCS module 3 and the high-voltage cascade energy storage system.

[0038] As an optional embodiment, the rectifier module 2 is a three-phase uncontrolled rectifier bridge;

[0039] Correspondingly, the power supply switch QF1 includes three power supply sub-switches, and the control switch KM1 includes three control sub-switches. The first ends of the three power supply sub-switches are connected one-to-one with the three phase lines of the power supply module 1, the second ends of the power supply sub-switches are connected one-to-one with the first ends of the control sub-switches, and the second ends of the three control sub-switches are connected one-to-one with the three input ends of the three-phase uncontrolled rectifier bridge.

[0040] It is not difficult to understand that when the power supply module 1 uses three-phase AC power, the corresponding power supply switch QF1 and the control switch KM1 need to be set with three power supply sub-switches and three control sub-switches that are respectively connected to the three phase lines of the power supply module 1 in sequence. At this time, the rectifier module 2 also needs to be implemented using a three-phase rectifier circuit, and a three-phase uncontrolled rectifier bridge is an optional method. The specific type and implementation method of the power supply sub-switches and control sub-switches are not specifically limited in this application. Usually, the three power supply sub-switches need to be implemented using switch devices of the same type and parameters, and the three control sub-switches need to be implemented using control devices of the same type and parameters, such as Figure 2 As shown, the three-phase uncontrolled rectifier bridge is realized by a first diode and a second diode connected in series, a third diode and a fourth diode connected in series, and a fifth diode and a sixth diode connected in series, and the two ends of the three series circuits are connected to the DC side of the PCS module 3, and the three series midpoints are respectively used as the three input ends of the rectifier module 2. Figure 2 As shown, for the nth test loop, that is, loop n, the three-phase uncontrolled rectifier bridge is composed of a first diode D1_n, a second diode D2_n, a third diode D3_n, a fourth diode D4_n, a fifth diode D5_n, and a sixth diode D6_n.

[0041] Specifically, considering that the power supply module 1 is generally implemented using three-phase alternating current, the power supply switch QF1 and the control switch KM1 need to be provided with three power supply sub-switches and three control sub-switches respectively connected in sequence to the three phase lines of the power supply module 1, and a three-phase rectifier module 2 needs to be adopted. The entire circuit structure is simple and easy to implement. The three-phase uncontrolled rectifier bridge can effectively realize the rectification function of the rectifier module 2. The components used are low in cost and small in size, which is conducive to the simple implementation of the entire PCS module 3 and the high-voltage cascade energy storage system.

[0042] As an optional embodiment, the sampling module 4 is connected to the control module via an optical fiber.

[0043] In practical applications, the PCS module 3 in the high-voltage cascade energy storage system is an independent finished product, and its external interfaces mainly include DC input (output), AC input (output), communication fiber optic interface, and liquid cooling in and out interface. The DC input (output) is the DC side of the PCS module 3, and the AC input (output) is the AC side of the PCS module 3. The communication fiber optic interface is used for communication between the PCS module 3 and the overall control system of the high-voltage cascade energy storage system, and the liquid cooling in and out interface is used to connect the liquid cooling device required by the PCS module 3. Therefore, the test circuit not only needs to solve the test of the power drive of the PCS module 3, but also can further test the heat dissipation and control management of the components.

[0044] It is understandable that, considering that further testing is needed on the control management of the PCS module 3, and the control management of the PCS module 3 is mainly implemented based on the communication fiber optic interface, the sampling module 4 and the control module in the present application directly utilize this communication fiber optic interface to communicate through optical fiber connection. At the same time, the control end of the PCS module 3 is also connected to the main control system of the high-voltage cascade energy storage system in the control cabinet through optical fiber. The control module communicates with n groups of PCS modules 3 through n pairs of optical fibers, which are numbered M1-Mn, and each pair of optical fibers is divided into a downlink optical fiber and an uplink optical fiber. The downlink optical fiber is a fast channel for the main control system to send switch commands in real time. At the same time, using the serial communication frame method, each frame of data contains a start bit, IGBT lock bit, left bridge PWM (Pulse Width Modulation) switch bit, right bridge PWM switch bit, pre-charge switch bit, main switch bit, bypass switch bit, stop bit and check complementary bit. In this way, the SVPWM (Space Vector Pulse Width Modulation) control switch waveform can be sent to the switch tube in the PCS module 3 at a very fast speed, thereby controlling the working process of the PCS module 3. The uplink optical fiber uses a method similar to the serial communication frame to transmit the relevant data such as the DC voltage, DC current, module temperature, module status, etc. detected by the sampling module 4 in the test loop to the control module in the form of 16-bit data packets, and the control module parses and restores them to relevant values ​​according to the agreed format. Furthermore, during the test process, the control module of the test circuit and the main control system can be implemented using the same main controller 51 .

[0045] Specifically, during the test process, the communication between the sampling module 4 and the control module, as well as the communication between the PCS module 3 and the main control system of the high-voltage cascade energy storage system can be achieved by utilizing the communication optical fiber interface reserved during the design of the PCS module 3 and by using optical fiber communication. Therefore, during the test process, the control module or the main control system can be used to complete the test process of the communication optical fiber interface of the PCS module 3 by checking whether the test process is smooth, thereby further improving the test process of the PCS module 3 and improving the safety and reliability of the entire PCS module 3.

[0046] As an optional embodiment, the control module includes a power module and a main controller 51 including a main control board, a sampling board, and a fiber optic board. The output end of the power module is connected to the power port of the main controller 51, the input end of the sampling board is connected to the output end of the sampling module 4, the output end is connected to the input end of the main control board, the output end of the main control board is connected to the input end of the fiber optic board, and the output end of the fiber optic board is connected to the control end of the PCS module 3.

[0047] It is not difficult to understand that the control module in the test circuit can be implemented by a control cabinet configured separately in the high-voltage cascade energy storage system. In this case, the control cabinet needs to include a power module main controller 51 of the control module. The main controller 51 can realize the signal detection system of the PCS module 3 through the cooperation of the sampling board and the sampling module 4. The power module mainly provides DC24V, DC±15V, DC5V and other direct currents, thereby supplying power to the main control board, sampling board, optical fiber board and other devices in the main controller 51 through the power port of the main controller 51. In general, the main control board requires 5V direct current, and the AD sampling board in the signal acquisition system requires ±15V direct current. The present application does not make any special restrictions on the specific types and implementation methods of the power module and the main controller 51. The power module can output different levels of power supply voltage according to the specific application of the main controller 51. The main control board, sampling board, and optical fiber board in the main controller 51 cooperate to implement the test process of the PCS module 3. The main control board serves as the controller of the entire test process and controls the implementation of the entire test process. The main control board receives the sampling results of the sampling module 4 through the sampling board. The main controller 51 uses AD sampling to collect the current and / or voltage of the AC load 6 circuits of n circuits to the main control board, which is used to perform closed-loop control of the load 6 power of the PCS module 3, overload protection and other operations, and implement the test of the PCS module 3 according to the sampling results. At the same time, the optical fiber board can also be used to send control instructions to the PCS module 3, such as the control signal of the switch tube in the PCS module 3; the main control board can also serve as the main control system of the high-voltage cascade energy storage system, and the same main control board is used to simultaneously implement the main control system of the high-voltage cascade energy storage system and the control module of the test circuit.

[0048] It should be noted that the main control board, sampling board, optical fiber board and other systems on the main controller 51 can use circuit boards of the same specifications as other control systems in the control cabinet of the high-voltage cascade energy storage system, so as to avoid test and control errors caused by different circuit board specifications, and avoid the problem of needing to conduct comprehensive verification again after redesign. The control software in the main controller 51 can also be compatible with related functional modules. The test process of the PCS module 3 mainly uses the sampling module 4 to collect the load 6 current of the n test loops, and ensures that the logic control and information reporting inside the PCS module 3 are sent and uploaded from the communication optical fiber, so that the test process is exactly the same as the program in the actual operation of the high-voltage cascade energy storage system, so that the hardware part of the PCS module 3 can be checked and verified, and the software can also be verified and tested.

[0049] Specifically, the control module of the test circuit and the main control system of the high-voltage cascade energy storage system are implemented using the same control cabinet, and can be further implemented using the same main controller 51, thereby achieving a complete simulation of the working process of the PCS module 3, which can not only test the hardware part of the PCS module 3, but also further verify the software corresponding to the control process of the normal working process of the PCS module 3, further ensuring the safety and reliability of the PCS module 3.

[0050] As an optional embodiment, the power module includes a main power supply, a backup power supply and a dual power supply circuit board 52 , and the output end of the main power supply and the output end of the backup power supply are both connected to the power port of the main controller 51 through the dual power supply circuit board 52 .

[0051] It is not difficult to understand that, considering that the reliability of the working process of the main controller 51 needs to meet certain requirements, the power module sets a dual power mode of a main power supply and a backup power supply. Both the main power supply and the backup power supply are connected to the power port of the main controller 51 through a dual power supply circuit board 52. When the main power supply fails, the backup power supply can be started to ensure the reliable operation of the main controller 51. At the same time, the main controller 51 may also participate in the control process of the high-voltage cascade energy storage system as the main control system. Therefore, the use of a dual power module can further ensure the reliable operation of the entire high-voltage cascade energy storage system. This application does not make any special restrictions on the specific types and implementation methods of the main power supply, backup power supply and dual power supply circuit board 52. Figure 2 As shown, the main power supply and the backup power supply are switched by switching switch KA3.

[0052] Specifically, in order to further ensure the reliable operation of the main controller 51, the dual power supply mode of the main power supply and the backup power supply set in the power supply module avoids abnormalities in the test process caused by power failure, ensures the reliable progress of the entire test process, and further improves the safety and reliability of the entire test circuit and the high-voltage cascade energy storage system.

[0053] As an optional embodiment, the control module further includes a human-machine interface 53 , a power port of the human-machine interface 53 is connected to a power port of the main controller 51 , and a communication port is connected to the main control board.

[0054] It is not difficult to understand that the control module can further include a human-machine interface 53 of an HMI (Human Machine Interface) operating system. The HMI operating system can provide display and operation of relevant information during the test process. The parameters such as the power value of the load of the PCS module 3 can be set through the HMI to realize control operations such as starting and stopping the load. The PCS module 3 can be controlled through the HMI. Further, the pipeline load test can be performed through the fully automatic background system, thereby realizing the test process of the liquid cooling device corresponding to the heat dissipation of the components of the PCS module 3. The power module generally needs to provide 24V DC power to the HMI. The specific type and implementation method of the human-machine interface 53 are not particularly limited in this application. Other test functions can be further realized through the cooperation of the main controller 51 and the HMI. The main controller 51 and the HMI can transmit the relevant parameters and variable information that need to be sent and set between the HMI and the main controller through the communication protocol format of the MODBUS-RTU of the RS485 interface.

[0055] Specifically, the control parameters of the main controller 51 can be set and regulated by the added human-machine interface 53, and the information such as the acquisition signal received by the main controller 51 can be displayed, so as to further improve the structure of the control module.

[0056] As an optional embodiment, the load 6 is an air-core reactor.

[0057] It is not difficult to understand that, considering the requirements of energy conservation and environmental protection, inductive load 6 is generally used in the test process. Inductive load 6 generates reactive power without actually consuming energy, so that the energy in the entire test circuit flows in capacitor C and inductor, with only a small amount of line loss and switching loss of power devices, and relatively low active power loss, thus avoiding excessive energy consumption. Inductive load 6 can be implemented by air-core reactors and the like. The specific type and implementation of air-core reactors are not specifically limited in this application. Figure 2 As shown, for the nth test loop, ie loop n, the load 6 is an inductor Ln.

[0058] Specifically, the load 6 on the AC side of the PCS module 3 can be set to an inductive load 6 such as an air-core reactor, thereby reducing the active power loss of the entire test circuit, avoiding excessive energy consumption, further expanding the scope of application of the entire test circuit, and facilitating the application and promotion of the entire test circuit.

[0059] As an optional embodiment, the power supply module 1 includes a circuit breaker QF0 and a voltage regulator T0, a first end of the circuit breaker QF0 is connected to the power supply, a second end is connected to the input end of the voltage regulator T0, and an output end of the voltage regulator T0 serves as an output end of the power supply module 1;

[0060] The voltage regulator T0 is used to adjust the output voltage output to the test circuit.

[0061] It is not difficult to understand that several test loops are powered by the same power supply module 1, and a voltage regulator T0 is provided in the power supply module 1 to adjust the output voltage, thereby realizing the test process of the PCS module 3 under different input voltage conditions; Figure 2 As shown, the AC power supplies of the n circuits are uniformly regulated by a 30kVA voltage regulator T0, which can adjust the voltage within a certain range. At the same time, the input side of the voltage regulator T0 is connected to the experimental power supply through the AC400V protection circuit breaker QF0 switch, and the circuit breaker QF0 can further protect the circuit. The specific type and implementation method of the circuit breaker QF0 and the voltage regulator T0 are not particularly limited in this application.

[0062] Specifically, for several test circuits, it is only necessary to use the same power supply module 1 for power supply, and set a voltage regulator T0 in the power supply module 1 to adjust the output voltage. The same power supply module 1 can be used to realize the power supply process of the test circuits of multiple PCS modules 3, and there is no need to set up multiple power supply modules 1, which further simplifies the circuit structure of the test circuit and is conducive to the simple implementation of the entire test circuit.

[0063] As an optional embodiment, the sampling module 4 is a current sensor.

[0064] It is not difficult to understand that the output voltage of the power supply module 1 of the test circuit determines the voltage condition of the PCS module 3, so the voltage of the PCS module 3 can be directly determined according to the output voltage of the power supply module 1, so the sampling module 4 mainly samples the current on the AC side of the PCS module 3, and on this basis, the power condition of the PCS module 3 can be further determined, so the sampling module 4 can use a current sensor to implement the test process of the PCS module 3. The specific type and implementation method of the current sensor are not particularly limited in this application, and can be implemented by using a Hall current sensor, such as Figure 2 As shown, for the nth test loop, ie loop n, the sampling module 4 is a Hall current sensor TAn.

[0065] Specifically, considering that the voltage of the PCS module 3 can be directly determined according to the output voltage of the power supply module 1, the sampling module 4 mainly collects the current of the PCS module 3. Therefore, the current sensor can be directly used to implement the sampling module 4. The entire circuit structure is simple and easy to implement. It can effectively realize the detection of the voltage, current and power of the PCS module 3. The components used are low in cost and small in size, which is conducive to the simple implementation of the entire PCS module 3 and the high-voltage cascade energy storage system.

[0066] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0067] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0068] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A test circuit, characterized in that: It includes a power supply module, a control module, a plurality of PCS modules and a plurality of test loops connected to the plurality of PCS modules in a one-to-one correspondence, wherein the test loop includes a power supply switch, a control switch, a rectifier module, a sampling module and a load; For any of the test loops, the first end of the power switch is connected to the output end of the power supply module, the second end is connected to the first end of the control switch, the second end of the control switch is connected to the output end of the rectifier module, the output end of the rectifier module is connected to the DC side of the PCS module, the input end of the sampling module is connected in series with the load, and the two ends of the series-connected circuit are connected to the AC side of the PCS module, the output end of the sampling module is connected to the input end of the control module, and the output end of the control module is connected to the control end of the PCS module; The sampling module is used to sample the output of the AC side of the PCS module so that the control module can complete the test process of the PCS module.

2. The test circuit according to claim 1, characterized in that: The PCS module includes a first switch tube, a second switch tube, a third switch tube, a fourth switch tube and a plurality of capacitors connected in parallel. The first switch tube and the second switch tube are connected in series, and the two ends of the series circuit are respectively connected to the two ends of the circuit after the capacitors are connected in parallel. The third switch tube and the fourth switch tube are connected in series, and the two ends of the series circuit are respectively connected to the two ends of the circuit after the capacitors are connected in parallel. The control end of the first switch tube, the control end of the second switch tube, the control end of the third switch tube, and the control end of the fourth switch tube are all connected to the output end of the control module. The two ends of the circuit after the plurality of capacitors are connected in parallel serve as the DC side of the PCS module, the series midpoint of the first switch tube and the second switch tube serves as the first end of the AC side of the PCS module, and the series midpoint of the third switch tube and the fourth switch tube serves as the second end of the AC side of the PCS module.

3. The test circuit according to claim 2, characterized in that: The rectifier module is a three-phase uncontrolled rectifier bridge; Correspondingly, the power supply switch includes three power supply sub-switches, and the control switch includes three control sub-switches. The first ends of the three power supply sub-switches are connected one-to-one with the three phase lines of the power supply module, the second ends of the power supply sub-switches are connected one-to-one with the first ends of the control sub-switches, and the second ends of the three control sub-switches are connected one-to-one with the three input ends of the three-phase uncontrolled rectifier bridge.

4. The test circuit according to claim 1, characterized in that: The sampling module is connected to the control module via an optical fiber.

5. The test circuit according to claim 4, characterized in that: The control module includes a power module and a main controller including a main control board, a sampling board, and a fiber optic board. The output end of the power module is connected to the power port of the main controller, the input end of the sampling board is connected to the output end of the sampling module, and the output end is connected to the input end of the main control board. The output end of the main control board is connected to the input end of the fiber optic board, and the output end of the fiber optic board is connected to the control end of the PCS module.

6. The test circuit according to claim 5, characterized in that: The power module includes a main power supply, a backup power supply and a dual power supply circuit board. The output end of the main power supply and the output end of the backup power supply are both connected to the power port of the main controller through the dual power supply circuit board.

7. The test circuit according to claim 5, characterized in that: The control module further comprises a human-machine interface, a power port of the human-machine interface is connected to a power port of the main controller, and a communication port is connected to the main control board.

8. The test circuit according to claim 1, characterized in that: The load is an air-core reactor.

9. The test circuit according to any one of claims 1 to 8, characterized in that: The power supply module includes a circuit breaker and a voltage regulator, wherein a first end of the circuit breaker is connected to a power supply, a second end is connected to an input end of the voltage regulator, and an output end of the voltage regulator serves as an output end of the power supply module; The voltage regulator is used to adjust the output voltage output to the test loop.

10. The test circuit according to claim 9, characterized in that: The sampling module is a current sensor.

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