A high voltage direct-mounted SVG device power module test system

Abstract

The invention discloses a high-voltage direct-hanging SVG device power module test system, comprising a power supply circuit, a flyback high-voltage output circuit, a voltage regulation feedback loop, and a main control circuit. The power supply circuit is used to provide power to the entire system. The flyback high-voltage output circuit is used to receive a first voltage output by the power supply circuit and output a controllable voltage for use in testing a power module under test. The first input end of the voltage regulation feedback loop is connected to the voltage output end of the flyback high-voltage output circuit. The second input end of the voltage regulation feedback loop is connected to the output end of the first reference output circuit. The input end of the first reference output circuit is connected to the output end of the main control circuit. The output end of the voltage regulation feedback loop is connected to the control input end of the flyback high-voltage output circuit. The main control circuit communicates with the power module under test. Compared with the traditional method, the system of the invention can greatly reduce the volume of SVG power module test equipment and improve test efficiency and automation level.

Description

Technical Field

[0001] The invention belongs to the technical field of power quality, and in particular relates to a power module testing system for a high-voltage direct-hanging SVG device. Background Art

[0002] At present, static VAR generators (SVG) are widely used, and the detection efficiency and test requirements of power modules are also improved. In the traditional test method, on the one hand, the voltage setting of the power module is obtained by stepping up the power frequency transformer and then obtaining it through uncontrolled rectification. It is large in size and relatively bulky. The voltage output fluctuates greatly during the test, which is not convenient for automated testing. On the other hand, the control unit in the test is not highly integrated, and the test efficiency is low. Summary of the invention

[0003] The present invention aims to overcome at least one defect in the prior art and provides a high-voltage direct-mounted SVG device power module testing system.

[0004] The technical solution of the present invention is implemented as follows: The present invention discloses a high-voltage direct-hanging SVG device power module test system, which is characterized by comprising a power supply circuit, a flyback high-voltage output circuit, a voltage regulation feedback loop, and a main control circuit. The power supply circuit is used to provide power to the entire system. The flyback high-voltage output circuit is used to receive a first voltage output by the power supply circuit and output a controllable voltage for use in testing the power module under test. The first input end of the voltage regulation feedback loop is connected to the voltage output end of the flyback high-voltage output circuit, the second input end of the voltage regulation feedback loop is connected to the output end of the first reference output circuit, the input end of the first reference output circuit is connected to the output end of the main control circuit, the output end of the voltage regulation feedback loop is connected to the control input end of the flyback high-voltage output circuit, and the main control circuit communicates with the power module under test.

[0005] Further, the flyback high-voltage output circuit includes at least one flyback transformer, one end of the primary winding of each flyback transformer is connected to the first voltage, the other end of the primary winding of the flyback transformer is connected to the drain of the main switch tube Q1, the source of the main switch tube Q1 is grounded via a resistor R39, the gate of the main switch tube Q1 is connected to the output end of the voltage regulation feedback loop via a driving resistor R33, and the flyback transformer is provided with at least one secondary output winding, and the outputs of the multiple secondary output windings are rectified and output in series;

[0006] One end of each secondary output winding is connected to the positive electrode of the rectifier diode, and the negative electrode of the rectifier diode is connected to the other end of the secondary output winding via a voltage-equalizing resistor. After each voltage-equalizing resistor is connected in series, one end is connected to the voltage output end and the other end is grounded.

[0007] Furthermore, the flyback high-voltage output circuit also includes a main switch tube Q3, the source of the main switch tube Q3 is connected to the source of the main switch tube Q1, the drain of the main switch tube Q3 is connected to the drain of the main switch tube Q1, and the gate of the main switch tube Q3 is connected to the output end of the voltage regulation feedback loop via the driving resistor R55.

[0008] Furthermore, a buffer circuit of a flyback power supply is connected between the two ends of the primary winding of the flyback transformer, and the buffer circuit of the flyback power supply includes a resistor R26, a diode D10, and a capacitor C19. One end of the resistor R26 is connected to one end of the primary winding of the flyback transformer and one end of the capacitor C19, the other end of the resistor R26 is connected to the cathode of the diode D10, the anode of the diode D10 is connected to the other end of the primary winding of the flyback transformer, and the other end of the capacitor C19 is connected to the cathode of the diode D10.

[0009] Furthermore, the voltage regulation feedback loop includes an operational amplifier circuit and a power supply regulation chip U5, wherein the first input end of the operational amplifier circuit is connected to the voltage output end of the flyback high voltage output circuit via a voltage divider circuit, the second input end of the operational amplifier circuit is connected to the output end of the first reference output circuit or the first output end of the second reference output circuit, the output end of the operational amplifier circuit is connected to the first input end of the optical coupler U6, the second input end of the optical coupler U6 is connected to the second voltage, the first output end of the optical coupler U6 is connected to the FB pin of the power supply regulation chip U5, and the optical coupler U 6 is grounded, the GATE pin of the power regulation chip U5 is the output end of the voltage regulation feedback loop, and is used to be connected to the control input end of the flyback high-voltage output circuit, the FB pin of the power regulation chip U5 is connected to the collector of the transistor Q2, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is respectively connected to one end of the resistor R30 and the first output end of the optocoupler U7, the other end of the resistor R30 is connected to the fourth voltage, the second output end of the optocoupler U7 is grounded, the first input end of the optocoupler U7 is connected to the second voltage, and the second input end of the optocoupler U7 is grounded.

[0010] Further, the first reference output circuit includes an operational amplifier U8A and an operational amplifier U10A, the in-phase input terminal of the operational amplifier U8A is connected to the first output terminal of the main control circuit via a resistor R43, the inverting input terminal of the operational amplifier U8A is respectively connected to one end of a resistor R11, one end of a capacitor C25, and an anode 1 of a photodiode of an optical coupler U9, the other end of the resistor R11 is grounded, the other end of the capacitor C25 is connected to the output terminal of the operational amplifier U8A, the cathode 1 of the photodiode of the optical coupler U9 is connected to a third voltage, and the LED cathode of the optical coupler U9 is grounded. The LED anode of the optocoupler U9 is connected to the output end of the operational amplifier U8A via a resistor R41, the cathode 2 of the photodiode of the optocoupler U9 is connected to the second voltage, the anode 2 of the photodiode of the optocoupler U9 is connected to the non-inverting input end of the operational amplifier U10A, the non-inverting input end of the operational amplifier U10A is grounded via a resistor R44, the inverting input end of the operational amplifier U10A is connected to the output end of the operational amplifier U10A via a resistor R40, one end of the output end of the operational amplifier U10A is connected to one end of the resistor R42, and the other end of the resistor R42 is the output end of the first reference output circuit.

[0011] Furthermore, the high-voltage direct-mounted SVG device power module test system of the present invention also includes an overcurrent protection circuit, which is used to perform real-time detection of the output current of the flyback high-voltage output circuit. Once the output exceeds the limit value, the main switch tube Q1 of the flyback high-voltage output circuit is controlled to be disconnected.

[0012] Furthermore, the high-voltage direct-mounted SVG device power module test system of the present invention further comprises an AC / DC voltage acquisition circuit, which is used to acquire the AC / DC voltage of the power module under test in real time and transmit it to the main control circuit.

[0013] Furthermore, the high-voltage direct-mounted SVG device power module test system of the present invention further includes an optical fiber communication interface circuit, which is connected to the main control circuit;

[0014] Furthermore, the high-voltage direct-mounted SVG device power module testing system of the present invention further includes a display circuit, and the display circuit is connected to the main control circuit.

[0015] The present invention has at least the following beneficial effects: the present invention provides a portable high-voltage power supply unit required by a high-voltage direct-mounted SVG device power module test system, the high-voltage power supply unit adopts a flyback switching power supply topology, utilizes a reasonable magnetic core winding method, and realizes a maximum 1400V controllable output voltage through multi-stage series connection on the secondary side. According to the test requirements of the power module to be tested, the present invention can quickly realize the output of different voltage test values, thereby improving the test efficiency of the power module.

[0016] Compared with the traditional method, the system of the present invention can greatly reduce the volume of SVG power module test equipment and improve the test efficiency and automation level. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be 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 paying creative work.

[0018] Figure 1 A functional block diagram of a high-voltage direct-mounted SVG device power module test system provided by an embodiment of the present invention;

[0019] Figure 2 A circuit diagram of a flyback high voltage output circuit provided by an embodiment of the present invention;

[0020] Figure 3 A circuit diagram of a voltage regulation feedback loop and an overcurrent protection circuit provided by an embodiment of the present invention;

[0021] Figure 4 A circuit diagram of a first reference output circuit and a current acquisition circuit provided in an embodiment of the present invention;

[0022] Figure 5 A circuit diagram of a second reference output circuit provided by an embodiment of the present invention;

[0023] Figure 6 A circuit diagram of a first part of a power supply circuit provided by an embodiment of the present invention;

[0024] Figure 7 A circuit diagram of a second part of a power supply circuit provided by an embodiment of the present invention;

[0025] Figure 8 A circuit diagram of the third part of the power supply circuit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present invention, unless otherwise specified, "multiple" and "several" mean two or more.

[0028] See also Figures 1 to 8 The embodiment of the present invention provides a high-voltage direct-mounted SVG device power module test system, including a power supply circuit, a high-voltage power supply unit, and a main control circuit. The high-voltage power supply unit includes a flyback high-voltage output circuit and a voltage regulation feedback loop. The power supply circuit is used to provide power to the entire system. The flyback high-voltage output circuit is used to receive a first voltage output by the power supply circuit and output a controllable voltage for testing the power module under test. The first input end of the voltage regulation feedback loop is connected to the voltage output end of the flyback high-voltage output circuit, the second input end of the voltage regulation feedback loop is connected to the output end of the first reference output circuit or the first output end of the second reference output circuit, the input end of the first reference output circuit is connected to the output end of the main control circuit, the output end of the voltage regulation feedback loop is connected to the control input end of the flyback high-voltage output circuit, and the main control circuit communicates with the power module under test.

[0029] The power supply circuit is used for converting AC input into various required voltage outputs.

[0030] The power supply circuit comprises a rectifier circuit, an input end of the rectifier circuit is connected to an AC input, and an output end of the rectifier circuit is used to output a first voltage.

[0031] The flyback high-voltage output circuit includes at least one flyback transformer, one end of the primary winding of each flyback transformer is connected to the first voltage, the other end of the primary winding of the flyback transformer is connected to the drain of the main switch tube Q1, the source of the main switch tube Q1 is grounded via a resistor R39, and the gate of the main switch tube Q1 is connected to the output end of the voltage regulation feedback loop via a driving resistor R33. The flyback transformer is provided with at least one secondary output winding, and the outputs of multiple secondary output windings are rectified and output in series.

[0032] The resistor R38 is connected in parallel to both ends of the resistor R39.

[0033] The gate of the main switch tube Q1 is connected to the source of the main switch tube Q1 via the resistor R36.

[0034] One end of each secondary output winding is connected to the positive electrode of the rectifier diode, and the negative electrode of the rectifier diode is connected to the other end of the secondary output winding via a voltage-equalizing resistor. After each voltage-equalizing resistor is connected in series, one end is connected to the voltage output end and the other end is grounded.

[0035] A capacitor is connected in parallel to both ends of each voltage-equalizing resistor, and the positive electrode of the capacitor is connected to the negative electrode of the rectifier diode.

[0036] The high-voltage direct-mounted SVG device power module test system of the present invention further comprises an indicator light, wherein the positive electrode of the indicator light is connected to the voltage output end via a resistor, and the negative electrode of the indicator light is grounded. Resistors are connected in parallel at both ends of the indicator light.

[0037] The flyback high-voltage output circuit also includes a main switch tube Q3, the source of the main switch tube Q3 is connected to the source of the main switch tube Q1, the drain of the main switch tube Q3 is connected to the drain of the main switch tube Q1, and the gate of the main switch tube Q3 is connected to the output end of the voltage regulation feedback loop via a driving resistor R55.

[0038] A buffer circuit of a flyback power supply is connected between the two ends of the primary winding of the flyback transformer, and the buffer circuit of the flyback power supply includes a resistor R26, a diode D10, and a capacitor C19, one end of the resistor R26 is connected to one end of the primary winding of the flyback transformer and one end of the capacitor C19, the other end of the resistor R26 is connected to the cathode of the diode D10, the anode of the diode D10 is connected to the other end of the primary winding of the flyback transformer, and the other end of the capacitor C19 is connected to the cathode of the diode D10. A resistor R54 is connected in series between the resistor R26 and the diode D10.

[0039] The flyback high voltage output circuit of this embodiment includes two flyback transformers, each flyback transformer is provided with two secondary output windings. The power supply adopts the flyback topology to output 4 power supplies. A single 350V power supply is connected in series after rectification to achieve a rated 1400V controllable power supply for SVG power module testing.

[0040] The voltage regulation feedback loop includes an operational amplifier circuit and a power supply regulation chip U5. The first input end of the operational amplifier circuit is connected to the voltage output end of the flyback high-voltage output circuit via a voltage divider circuit. The second input end of the operational amplifier circuit is connected to the output end of the first reference output circuit or the first output end of the second reference output circuit. The output end of the operational amplifier circuit is connected to the first input end of the optocoupler U6. The second input end of the optocoupler U6 is connected to the second voltage. The first output end of the optocoupler U6 is connected to the FB pin of the power supply regulation chip U5. The second output end of the optocoupler U6 is grounded. The GATE pin of the power supply regulation chip U5 is the output end of the voltage regulation feedback loop, which is used to be connected to the control input end of the flyback high-voltage output circuit. The FB pin of the power supply regulation chip U5 is connected to the collector of the transistor Q2. The emitter of the transistor Q2 is grounded. The base of the transistor Q2 is respectively connected to one end of the resistor R30 and the first output end of the optocoupler U7. The other end of the resistor R30 is connected to the fourth voltage. The second output end of the optocoupler U7 is grounded. The first input end of the optocoupler U7 is connected to the second voltage. The second input end of the optocoupler U7 is grounded. Setting up optocoupler U7 and transistor Q2 etc. can play the role of power supply protection.

[0041] The FB pin of the power regulator chip U5 is grounded via capacitor C23.

[0042] The SENSE pin of the power regulation chip is connected to one end of the resistor R34 , and the other end of the resistor R34 is connected to the source of the main switch tube Q1 .

[0043] The operational amplifier circuit includes an operational amplifier U4B, wherein the in-phase input terminal of the operational amplifier U4B is connected to the first reference voltage via a resistor R24, the inverting input terminal of the operational amplifier U4B is connected to one end of a resistor R23, the other end of the resistor R23 is connected to the voltage output terminal of the flyback high-voltage output circuit via a voltage divider circuit, and the inverting input terminal of the operational amplifier U4B is connected to the output terminal of the operational amplifier U4B via a resistor R22. The output terminal of the operational amplifier U4B is connected to the cathode of the diode D7, the anode of the diode D7 is connected to the first input terminal of the optical coupler U6, the inverting input terminal of the operational amplifier U4B is connected to one end of the resistor R21, the other end of the resistor R21 is connected to one end of the capacitor C17, and the other end of the capacitor C17 is connected to the output terminal of the operational amplifier U4B.

[0044] The first reference output circuit includes an operational amplifier U8A and an operational amplifier U10A. The in-phase input terminal of the operational amplifier U8A is connected to the first output terminal of the main control circuit via a resistor R43. The inverting input terminal of the operational amplifier U8A is respectively connected to one end of a resistor R11, one end of a capacitor C25, and an anode 1 of a photodiode of an optical coupler U9. The other end of the resistor R11 is grounded. The other end of the capacitor C25 is connected to the output terminal of the operational amplifier U8A. The cathode 1 of the photodiode of the optical coupler U9 is connected to a third voltage. The cathode of the LED of the optical coupler U9 is grounded. The LED anode of the optocoupler U9 is connected to the output end of the operational amplifier U8A via a resistor R41, the cathode 2 of the photodiode of the optocoupler U9 is connected to the second voltage, the anode 2 of the photodiode of the optocoupler U9 is connected to the non-inverting input end of the operational amplifier U10A, the non-inverting input end of the operational amplifier U10A is grounded via a resistor R44, the inverting input end of the operational amplifier U10A is connected to the output end of the operational amplifier U10A via a resistor R40, one end of the output end of the operational amplifier U10A is connected to one end of the resistor R42, and the other end of the resistor R42 is the output end of the first reference output circuit.

[0045] The second reference output circuit includes a voltage regulator tube, an adjustable resistor and a plurality of resistors and capacitors. The positive electrode of the voltage regulator tube U3 is grounded, and the negative electrode of the voltage regulator tube U3 is respectively connected to one end of the resistor R6, one end of the resistor R7, one end of the resistor R8, one end of the capacitor C13, and the control electrode of the voltage regulator tube U3. The other end of the resistor R6 is connected to the second voltage, and the other end of the resistor R7 is respectively connected to the second reference voltage output end and one end of the resistor R10. The other end of the resistor R10 is grounded, and the other end of the capacitor C13 is grounded. The other end of the resistor R8 is connected to one end of the adjustable resistor, and the other end of the adjustable resistor is grounded. The control end of the adjustable resistor is connected to one end of the resistor R9. The other end of the resistor R9 is respectively connected to the first reference voltage output end and one end of the capacitor C15, and the other end of the capacitor C15 is grounded.

[0046] The high-voltage power supply unit also includes a current collection circuit, the input end of the current collection circuit is connected to the current output end of the flyback high-voltage output circuit, and the output end of the current collection circuit is connected to the first input end of the main control circuit.

[0047] The current acquisition circuit includes an operational amplifier U10B and an operational amplifier U8B. The in-phase input terminal of the operational amplifier U10B is connected to the current output terminal of the flyback high-voltage output circuit via a resistor R49. The inverting input terminal of the operational amplifier U10B is respectively connected to one end of a resistor R46, one end of a capacitor C30, and an anode 1 of a photodiode of an optical coupler U13. The other end of the resistor R46 is grounded, the other end of the capacitor C30 is connected to the output terminal of the operational amplifier U10B, the cathode 1 of the photodiode of the optical coupler U13 is connected to a second voltage, and the cathode 1 of the LED of the optical coupler U13 is connected to a second voltage. Grounded, the LED anode of the optocoupler U13 is connected to the output end of the operational amplifier U10B via a resistor R47, the cathode 2 of the photodiode of the optocoupler U13 is connected to the third voltage, the anode 2 of the photodiode of the optocoupler U13 is connected to the non-inverting input end of the operational amplifier U8B, the non-inverting input end of the operational amplifier U8B is grounded via a resistor R50, the inverting input end of the operational amplifier U8B is connected to the output end of the operational amplifier U8B via a resistor R45, one end of the output end of the operational amplifier U8B is connected to one end of the resistor R48, and the other end of the resistor R48 is the output end of the current acquisition circuit.

[0048] The high-voltage power supply unit also includes an overcurrent protection circuit, which is used to perform real-time detection of the output current of the flyback high-voltage output circuit. Once the output exceeds the limit value, the main switch tube Q1 of the flyback high-voltage output circuit is controlled to be disconnected.

[0049] The overcurrent protection circuit includes an operational amplifier U4A, wherein the in-phase input terminal of the operational amplifier U4A is connected to a second reference voltage, i.e., (second), via a resistor R20, the inverting input terminal of the operational amplifier U4A is connected to one end of a resistor R19, the other end of the resistor R19 is connected to a current output end of a flyback high-voltage output circuit, the inverting input terminal of the operational amplifier U4A is connected to the output terminal of the operational amplifier U4A via a resistor R18, the output terminal of the operational amplifier U4A is connected to the cathode of a diode D6, the anode of the diode D6 is connected to the anode of a diode D7 or the first input terminal of an optocoupler U6, the inverting input terminal of the operational amplifier U4A is connected to one end of a resistor R17, the other end of the resistor R17 is connected to one end of a capacitor C16, and the other end of the capacitor C16 is connected to the output terminal of the operational amplifier U4A.

[0050] In this specific embodiment: the overcurrent protection circuit is as follows: Figure 3 As shown. U4, R20, R19, R18, R17, C16, and D6 form a 200-fold operational amplifier circuit. Once the overcurrent value exceeds the set threshold, the OUTVC value is pulled down, causing the power chip output to lock, thus achieving a protection function.

[0051] The high voltage power supply unit further includes a sampling resistor R35, one end of which is connected to the other end of the secondary output winding Ns2, the other end of which is a current output terminal CS1, and the other end of the secondary output winding Ns2 is grounded.

[0052] In this specific embodiment: the high-voltage output unit uses 4 sets of winding outputs to be rectified and connected in series, and is equipped with a voltage-equalizing resistor. Figure 2 As shown, specifically, Q1 and Q3 are the main switch tubes of the flyback circuit, which are used in parallel to increase the power of the power supply. T2 and T3 are flyback transformers with almost the same winding process and electrical parameters. D10, R26, R54, and C19 constitute the buffer circuit of the flyback power supply. R33 and R55 are the driving resistors of the main switch tube. Ns1 to Ns2 are secondary output windings. D8, D9, D11, and D14 are output rectifier diodes that respectively achieve a maximum voltage output of 350V. R35 is a sampling resistor to achieve output current value acquisition.

[0053] The flyback high-voltage output circuit adopts a flyback circuit topology, utilizes the multi-winding output of a high-frequency magnetic core, and connects them in series after rectification to achieve control and miniaturization of the 1400V high-voltage output.

[0054] The overcurrent protection circuit performs real-time detection on the high-voltage output current. Once the output exceeds the limit value, the power chip blocks the output to achieve overcurrent protection.

[0055] The voltage regulation feedback loop receives the analog signal instruction sent by the automatic control unit in real time and outputs the corresponding voltage value.

[0056] The high-voltage direct-mounted SVG device power module test system of the present invention further comprises an AC / DC voltage acquisition circuit, which is used to acquire the AC / DC voltage of the power module under test in real time and transmit it to the main control circuit. The AC / DC voltage acquisition circuit acquires the AC / DC voltage of the power unit under test in real time.

[0057] The high-voltage direct-hanging SVG device power module testing system of the present invention further comprises an optical fiber communication interface circuit, and the optical fiber communication interface circuit is connected to the main control circuit.

[0058] The main control circuit communicates with the power module under test through optical fiber. The main control circuit can also communicate with the host computer through a communication circuit.

[0059] The high-voltage direct-mounted SVG device power module testing system of the present invention further comprises a display circuit, and the display circuit is connected to the main control circuit.

[0060] The main control circuit of this embodiment uses an FPGA chip, but is not limited to the FPGA chip, and a single-chip microcomputer and the like may also be used.

[0061] The present invention provides a portable high-voltage power supply unit required for a high-voltage direct-mounted SVG device power module test system. The high-voltage power supply unit adopts the topology of a flyback switching power supply, and utilizes a reasonable magnetic core winding method to achieve a maximum controllable output voltage of 1400V through multi-stage series connection on the secondary side. The main control circuit of the present invention relies on an FPGA chip to realize automatic acquisition and analysis of the AC and DC voltages of the SVG power module, automatic control of a given DC voltage required for power module testing, module communication, and test result output. Compared with traditional methods, the present invention can greatly reduce the volume of SVG power module testing equipment and improve test efficiency and automation level.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high voltage direct-mounted SVG device power module test system, characterized in that: It includes a power supply circuit, a flyback high-voltage output circuit, a voltage regulation feedback loop, and a main control circuit. The power supply circuit is used to provide power to the entire system. The flyback high-voltage output circuit is used to receive a first voltage output by the power supply circuit and output a controllable voltage for testing a power module under test. The first input end of the voltage regulation feedback loop is connected to the voltage output end of the flyback high-voltage output circuit, the second input end of the voltage regulation feedback loop is connected to the output end of the first reference output circuit, the input end of the first reference output circuit is connected to the output end of the main control circuit, the output end of the voltage regulation feedback loop is connected to the control input end of the flyback high-voltage output circuit, and the main control circuit communicates with the power module under test. The voltage regulation feedback loop includes an operational amplifier circuit and a power supply regulation chip U5. The first input end of the operational amplifier circuit is connected to the voltage output end of the flyback high-voltage output circuit via a voltage divider circuit. The second input end of the operational amplifier circuit is connected to the output end of the first reference output circuit or the first output end of the second reference output circuit. The output end of the operational amplifier circuit is connected to the first input end of the optocoupler U6. The second input end of the optocoupler U6 is connected to the second voltage. The first output end of the optocoupler U6 is connected to the FB pin of the power supply regulation chip U5. The second output end of the optocoupler U6 is grounded. The GATE pin of the power supply regulation chip U5 is the output end of the voltage regulation feedback loop, which is used to be connected to the control input end of the flyback high-voltage output circuit. The FB pin of the power supply regulation chip U5 is connected to the collector of the transistor Q2. The emitter of the transistor Q2 is grounded. The base of the transistor Q2 is respectively connected to one end of the resistor R30 and the first output end of the optocoupler U7. The other end of the resistor R30 is connected to the fourth voltage. The second output end of the optocoupler U7 is grounded. The first input end of the optocoupler U7 is connected to the second voltage. The second input end of the optocoupler U7 is grounded.

2. The high-voltage direct-mounted SVG device power module test system according to claim 1, characterized in that: The flyback high-voltage output circuit includes at least one flyback transformer, one end of the primary winding of each flyback transformer is connected to the first voltage, the other end of the primary winding of the flyback transformer is connected to the drain of the main switch tube Q1, the source of the main switch tube Q1 is grounded via a resistor R39, and the gate of the main switch tube Q1 is connected to the output end of the voltage regulation feedback loop via a driving resistor R33, and the flyback transformer is provided with at least one secondary output winding, and the outputs of the multiple secondary output windings are rectified and output in series; One end of each secondary output winding is connected to the positive electrode of the rectifier diode, and the negative electrode of the rectifier diode is connected to the other end of the secondary output winding via a voltage-equalizing resistor. After each voltage-equalizing resistor is connected in series, one end is connected to the voltage output end and the other end is grounded.

3. The high voltage direct-mounted SVG device power module test system according to claim 2, characterized in that: The flyback high-voltage output circuit also includes a main switch tube Q3, the source of the main switch tube Q3 is connected to the source of the main switch tube Q1, the drain of the main switch tube Q3 is connected to the drain of the main switch tube Q1, and the gate of the main switch tube Q3 is connected to the output end of the voltage regulation feedback loop via a driving resistor R55.

4. The high-voltage direct-mounted SVG device power module test system according to claim 2, characterized in that: A buffer circuit of a flyback power supply is connected between the two ends of the primary winding of the flyback transformer. The buffer circuit of the flyback power supply includes a resistor R26, a diode D10, and a capacitor C19. One end of the resistor R26 is connected to one end of the primary winding of the flyback transformer and one end of the capacitor C19, the other end of the resistor R26 is connected to the cathode of the diode D10, the anode of the diode D10 is connected to the other end of the primary winding of the flyback transformer, and the other end of the capacitor C19 is connected to the cathode of the diode D10.

5. The high-voltage direct-mounted SVG device power module test system according to claim 1, characterized in that: The first reference output circuit includes an operational amplifier U8A and an operational amplifier U10A. The in-phase input terminal of the operational amplifier U8A is connected to the first output terminal of the main control circuit via a resistor R43. The inverting input terminal of the operational amplifier U8A is respectively connected to one end of a resistor R11, one end of a capacitor C25, and an anode 1 of a photodiode of an optical coupler U9. The other end of the resistor R11 is grounded. The other end of the capacitor C25 is connected to the output terminal of the operational amplifier U8A. The cathode 1 of the photodiode of the optical coupler U9 is connected to a third voltage. The cathode of the LED of the optical coupler U9 is grounded. The LED anode of the optocoupler U9 is connected to the output end of the operational amplifier U8A via a resistor R41, the cathode 2 of the photodiode of the optocoupler U9 is connected to the second voltage, the anode 2 of the photodiode of the optocoupler U9 is connected to the non-inverting input end of the operational amplifier U10A, the non-inverting input end of the operational amplifier U10A is grounded via a resistor R44, the inverting input end of the operational amplifier U10A is connected to the output end of the operational amplifier U10A via a resistor R40, one end of the output end of the operational amplifier U10A is connected to one end of the resistor R42, and the other end of the resistor R42 is the output end of the first reference output circuit.

6. The high-voltage direct-mounted SVG device power module test system according to claim 1, characterized in that: It also includes an overcurrent protection circuit, which is used to perform real-time detection of the output current of the flyback high-voltage output circuit. Once the output exceeds a limit value, the main switch tube Q1 of the flyback high-voltage output circuit is controlled to be disconnected.

7. The high-voltage direct-mounted SVG device power module test system according to claim 1, characterized in that: It also includes an AC / DC voltage acquisition circuit, which is used to acquire the AC / DC voltage of the power module under test in real time and transmit it to the main control circuit.

8. The high-voltage direct-mounted SVG device power module test system according to claim 1, characterized in that: It also includes an optical fiber communication interface circuit, which is connected to the main control circuit.

9. The high-voltage direct-mounted SVG device power module test system according to claim 1, characterized in that: It also includes a display circuit, which is connected to the main control circuit.

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