System and method for testing performance of hybrid on-load tap-changer thyristor module

Abstract

The invention provides a system and method for testing the performance of a hybrid on-load tap-changer thyristor module, and the system comprises a current source unit which is connected with a control unit and a to-be-tested thyristor module, and is used for applying a current to the to-be-tested thyristor module after receiving an instruction of the control unit; the control unit is respectively connected with the current source unit and the data acquisition unit and is used for performing signal analysis according to the information sent by the data acquisition unit so as to extract the characteristic quantity of the thyristor module to be tested and controlling the current source unit to apply current to the thyristor module to be tested; the data acquisition unit is respectively connected with the current source unit, the to-be-tested thyristor module and the control unit and is used for acquiring electric signals output by the to-be-tested thyristor module and the current source unit; and the trigger source unit is respectively connected with the current source unit and the thyristor module to be tested, and is used for controlling the trigger source unit to apply a given trigger waveform to the thyristor module to be tested after the phase of the current output by the current source unit is detected.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and more particularly to a system and method for testing the performance of a hybrid on-load tap changer thyristor module. Background Art

[0002] In recent years, hybrid transformer on-load tap-changers with thyristor-assisted arc extinguishing have developed rapidly and have been commercially applied. On the basis of ordinary oil-immersed on-load tap-changers, thyristor modules are added to avoid contact erosion and transformer oil pollution during switching. Hybrid on-load tap-changers have the above advantages, but as a new type of on-load tap-changer, there is still a lack of corresponding research on its test and testing, especially the test and testing of the performance of the added thyristor module. Summary of the invention

[0003] In order to solve the technical problem that there is a lack of technology for testing the performance of a hybrid transformer on-load tap changer thyristor module in the background technology, the present invention provides a system for testing the performance of a hybrid on-load tap changer thyristor module, the system comprising:

[0004] A current source unit, which is connected to the control unit and the thyristor module to be tested respectively, and is used to apply current to the thyristor module to be tested after receiving an instruction from the control unit;

[0005] A control unit, which is connected to the current source unit and the data acquisition unit respectively, and is used to perform signal analysis according to the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and control the current source unit to apply current to the thyristor module to be tested;

[0006] The data acquisition unit is connected to the current source unit, the thyristor module to be tested and the control unit respectively, and is used for acquiring the electrical signals output by the thyristor module to be tested and the current source unit.

[0007] The trigger source unit is connected to the current source unit and the thyristor module to be tested respectively, and is used to control the trigger source unit to apply a given trigger waveform to the thyristor module to be tested after detecting the phase of the output current of the current source unit.

[0008] Furthermore, the current source unit includes a three-phase power supply, a rectifier circuit, a single-phase inverter H-bridge, an isolation transformer and a capacitor group connected in sequence, wherein the 380V three-phase power supply is rectified by the rectifier circuit, and according to the instructions issued by the control unit, the single-phase inverter H-bridge outputs a current waveform of a specified amplitude, and after passing through the isolation transformer, the voltage of the current source unit is supported by the capacitor group and output to the thyristor module to be tested.

[0009] Furthermore, the data acquisition unit includes a measuring probe and an acquisition card, wherein the measuring probe is respectively connected to the current source unit, the thyristor module to be tested and the acquisition card, and is used to collect the electrical signals output by the current source unit and the thyristor module to be tested, and send them to the acquisition card, and the acquisition card is used to convert the received electrical signals into digital signals and transmit them to the control unit.

[0010] Furthermore, the electrical signals collected by the measuring probe include voltage signals and current signals.

[0011] Furthermore, the control unit includes a main controller and a control board, wherein the control board is connected to the current source unit, and the main controller is connected to the data acquisition unit.

[0012] Furthermore, the main controller is a PXI e series controller of National Instruments, Inc., and the control board is a control board card composed of a digital signal processor DSP and a field programmable gate array FPGA.

[0013] Furthermore, the trigger source unit includes a phase-locked loop, an arbitrary waveform generator and a power amplifier connected in sequence. The phase-locked loop is connected to the current source unit to collect the phase of the output current of the current source unit to provide an output phase reference for the arbitrary waveform generator. The power amplifier amplifies the trigger signal generated by the arbitrary waveform generator and applies it to the thyristor module to be tested.

[0014] According to another aspect of the present invention, the present invention provides a method for testing the performance of a hybrid on-load tap changer thyristor module, the method comprising:

[0015] The current source unit applies current to the thyristor module to be tested;

[0016] The trigger source unit identifies the output phase of the current source unit and applies a specific trigger signal to the gate of the thyristor module to be tested at different phases;

[0017] The data acquisition unit collects the gate and cathode electrical signals of the thyristor module to be tested

[0018] The data acquisition unit converts the received electrical signal into a digital signal and sends it to the control unit;

[0019] The control unit performs signal analysis according to the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and determines the performance of the thyristor module to be tested.

[0020] Furthermore, the current source unit applies current to the thyristor module to be tested, including:

[0021] After the 380V three-phase power supply in the current source unit is rectified by the rectifier circuit, the single-phase inverter H-bridge outputs a current waveform of a specified amplitude according to the instruction issued by the control unit. After passing through the isolation transformer, the voltage of the current source unit is supported by the capacitor group and output to the thyristor module to be tested.

[0022] Furthermore, the trigger source unit identifies the output phase of the current source unit, and applies a specific trigger signal to the gate of the thyristor module to be tested at different phases, including:

[0023] The phase-locked loop in the trigger source unit identifies the phase of the output current of the current source unit, controls the arbitrary waveform generator to output a trigger signal at different phases according to a given formula with a certain step size, and outputs the trigger signal to the gate of the thyristor module to be tested after being amplified by the power amplifier.

[0024] Furthermore, the data acquisition unit converts the received electrical signal into a digital signal and sends it to the control unit, including:

[0025] The measuring probe of the data acquisition unit collects fast transient electrical signals such as gate voltage, current, cathode voltage, and current of the thyristor module to be tested;

[0026] After receiving the fast transient electrical signal output by the measuring probe, the acquisition card of the data acquisition unit converts the fast transient electrical signal into a digital signal and transmits it to the control unit.

[0027] Furthermore, the measuring probe of the data acquisition unit acquires the electrical signal output by the thyristor module to be tested, including acquiring a voltage signal and a current signal.

[0028] Furthermore, the control unit performs signal analysis based on the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and determines the performance index of the thyristor module to be tested. The control unit adopts NI's PXI e controller and an acquisition card adapted to the PXI e controller, such as NI PXI e-5105 and NI PXI e-5122. After combination, the control unit uses a targeted signal acquisition and signal processing program developed in the NI Labview environment to analyze and extract electrical signals.

[0029] Furthermore, the characteristic quantities of the thyristor module to be tested include gate current rising rate, gate voltage rising rate, trigger time, turn-off time, recovery voltage amplitude, recovery voltage rising rate and triggerable phase interval.

[0030] The system and method for testing the performance of the hybrid on-load tap changer thyristor module of the present invention applies current to the thyristor module to be tested through a current source unit, collects electrical signals through a digital acquisition unit and transmits them to a control unit for signal analysis, thereby extracting characteristic quantities of the thyristor to be tested. Compared with the prior art, the system and method have the following beneficial effects:

[0031] (1) The hysteresis-controlled current source of the present invention can simulate the working condition of the thyristor module in the hybrid on-load tap changer. Compared with the test circuit using the transformer method or the resonance method, it requires less equipment and is more flexible.

[0032] (2) Using NI's PXI e and combining it with an acquisition card compatible with PXI e, develop targeted signal acquisition and signal processing programs in the NI Labview environment. Functions can be added as needed, making it more versatile. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0034] Figure 1 is a structural diagram of a system for testing the performance of a hybrid on-load tap changer thyristor module according to a specific embodiment of the present invention;

[0035] Figure 2 is a simplified circuit diagram of a system for testing the performance of a hybrid on-load tap changer thyristor module according to a specific embodiment of the present invention;

[0036] Figure 3 The flowchart is a method for testing the performance of a hybrid on-load tap changer thyristor module according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0037] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0038] Unless otherwise specified, the terms used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0039] Figure 11 is a structural diagram of a system for testing the performance of a hybrid on-load tap changer thyristor module according to a specific embodiment of the present invention. Figure 1 As shown, the system 100 for testing the performance of a hybrid on-load tap changer thyristor module of the present invention comprises:

[0040] A current source unit 101, which is connected to the control unit 102 and the thyristor module to be tested 103 respectively, and is used to apply current to the thyristor module to be tested 103 after receiving an instruction from the control unit 102;

[0041] A control unit 102, which is connected to the current source unit 101 and the data acquisition unit 104 respectively, and is used to perform signal analysis according to the information sent by the data acquisition unit 104 to extract the characteristic quantity of the thyristor module 103 to be tested, and control the current source unit 101 to apply current to the thyristor module 103 to be tested;

[0042] A data acquisition unit 104, which is connected to the current source unit 101, the thyristor module to be tested 103 and the control unit 102 respectively, and is used to collect electrical signals output by the thyristor module to be tested 103 and the current source unit 101;

[0043] The trigger source unit 105 is connected to the current source unit 102 and the thyristor module 103 to be tested respectively, and is used to control the trigger source unit to apply a given trigger waveform to the thyristor module 103 to be tested after detecting the phase of the output current of the current source unit 102 .

[0044] Preferably, the current source unit 101 includes a three-phase power supply 111, a rectifier circuit 112, a single-phase inverter H-bridge 113, an isolation transformer 114 and a capacitor group 115 connected in sequence, wherein the 380V three-phase power supply 111 is rectified by the rectifier circuit 112, and according to the instruction issued by the control unit 102, the single-phase inverter H-bridge 113 outputs a current waveform of a specified amplitude, and after passing through the isolation transformer 114, the capacitor group 115 supports the voltage of the current source unit 101 and outputs it to the thyristor module 103 to be tested.

[0045] In the current source unit 101, the three-phase power supply 111, the rectifier circuit 112, the isolation transformer 114 and the capacitor bank 115 are all uncontrollable, so the control signal of the control unit 102 is applied to the single-phase inverter H-bridge 113 to control the operation of the power electronic devices in the single-phase inverter H-bridge 113, thereby outputting a current waveform of a specified amplitude. Among them, the basis for the current source unit to output a current waveform of a specified amplitude is based on the user's test needs. For example, if the user's product requires a test current of 1000A, it is necessary to output a current of 1000A.

[0046] Preferably, the data acquisition unit 104 includes a measuring probe 141 and an acquisition card 142, wherein the measuring probe 141 is respectively connected to the current source unit 101, the thyristor module to be tested 103 and the acquisition card 142, and is used to collect the electrical signals output by the current source unit 101 and the thyristor module to be tested 103, and send them to the acquisition card 142, and the acquisition card 142 is used to convert the received electrical signals into digital signals and transmit them to the control unit 102.

[0047] Preferably, the electrical signals collected by the measuring probe 141 include voltage signals and current signals.

[0048] Preferably, the control unit 102 includes a main controller 121 and a control board 122 , wherein the control board 122 is connected to the current source unit 101 , and the main controller 121 is connected to the data acquisition unit 104 .

[0049] Preferably, the main controller 121 is a PXI e series controller from National Instruments, Inc., and the control board 122 is a control board card that is a combination of a digital signal processor DSP and a field programmable gate array FPGA.

[0050] Preferably, the trigger source unit 105 includes a phase-locked loop 151, an arbitrary waveform generator 152 and a power amplifier 153 connected in sequence. The phase-locked loop 151 is connected to the current source unit 102 to collect the phase of the output current of the current source unit 102 to provide an output phase reference for the arbitrary waveform generator 152. The power amplifier 153 amplifies the trigger signal generated by the arbitrary waveform generator 152 and applies it to the thyristor module 103 to be tested.

[0051] For the current source unit 101, in each power frequency cycle of its output current waveform, the output voltage of the arbitrary waveform generator 152 in the trigger source unit 105 is u f .

[0052]

[0053] Among them, u f represents the output voltage of the arbitrary waveform generator 152, t represents time, Δt, K1, K2, α1, α2 are a series of process coefficients, R is the equivalent resistance of the entire thyristor module, C is the equivalent resistance of the entire thyristor module, L is the equivalent inductance of the entire thyristor module, R s is the residual resistance of the mechanical contacts connected in parallel with the thyristor module in the hybrid on-load tapchanger after arcing, U m It represents the maximum recovery voltage generated by the mechanical contacts connected in parallel with the thyristor module in the hybrid on-load tapchanger after arcing, U sIt indicates the recovery voltage of the mechanical contact connected in parallel with the thyristor module in the hybrid on-load tap-changer at the current zero crossing point after arcing. It indicates that the phase-locked loop 151 identifies the instantaneous value of the phase of the output current waveform of the current source unit 101.

[0054] Figure 2 FIG. 1 is a simplified circuit diagram of a system for testing the performance of a hybrid on-load tap changer thyristor module according to a specific embodiment of the present invention. Figure 2 As shown, SCR is a thyristor, A is the anode, K is the cathode, and G is the gate. The circuit composed of the current source unit, the thyristor SCR, and the load Z is the main circuit. The current of the main circuit flows out from the current source unit and flows through the anode A, cathode K, and load Z of the thyristor SCR. The trigger circuit current is generated by the trigger source unit and flows through the gate current limiting resistor R, the gate protection diode D, the gate G, and cathode K of the thyristor SCR. The varistor MOV is used as a protection device for the thyristor SCR. When the voltage across the thyristor SCR exceeds the protection value, it discharges the current to protect the thyristor SCR from breakdown. The measuring probes V1, A1, A2, and V2 respectively measure the voltage between the anode and cathode of the thyristor module, the current of the main circuit, the current of the trigger circuit, and the voltage between the gate and the cathode, and convert the measured voltage and current signals into digital signals through the acquisition card and transmit them to the control unit, which analyzes the signals and extracts the relevant feature quantities.

[0055] When the output voltage u of the arbitrary waveform generator 152 f The output voltage U after amplification by the power amplifier 153 f When the following conditions are met

[0056]

[0057] That is, after passing through the gate current limiting resistor R and the gate protection diode D, the current in the trigger circuit is greater than the trigger current of the thyristor SCR and can last for a certain period of time, then the thyristor SCR is triggered. Where R represents the resistance value of the gate current limiting resistor, R D Represents the equivalent resistance of the gate protection diode D, I T Indicates the trigger current of the thyristor SCR.

[0058] Figure 3 FIG. 1 is a flow chart of a method for testing the performance of a hybrid on-load tap changer thyristor module according to a specific embodiment of the present invention. Figure 3 As shown, the method 300 for testing the performance of a hybrid on-load tap changer thyristor module according to the present invention starts from step 301 .

[0059] In step 301, a current source unit applies current to a thyristor module to be tested;

[0060] In step 302, the trigger source unit identifies the output phase of the current source unit and applies a specific trigger signal to the gate of the thyristor module to be tested at different phases;

[0061] In step 303, the data acquisition unit acquires gate and cathode electrical signals of the thyristor module to be tested;

[0062] In step 304, the data acquisition unit converts the received electrical signal into a digital signal and sends it to the control unit;

[0063] In step 305 , the control unit performs signal analysis according to the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and determines the performance of the thyristor module to be tested.

[0064] Preferably, the current source unit applies current to the thyristor module to be tested, comprising:

[0065] After the 380V three-phase power supply in the current source unit is rectified by the rectifier circuit, the single-phase inverter H-bridge outputs a current waveform of a specified amplitude according to the instruction issued by the control unit. After passing through the isolation transformer, the voltage of the current source unit is supported by the capacitor group and output to the thyristor module to be tested.

[0066] Preferably, the trigger source unit identifies the output phase of the current source unit, and applies a specific trigger signal to the gate of the thyristor module to be tested at different phases, including:

[0067] The phase-locked loop in the trigger source unit identifies the phase of the output current of the current source unit, controls the arbitrary waveform generator to output a trigger signal at different phases according to a given formula with a certain step size, and outputs the trigger signal to the gate of the thyristor module to be tested after being amplified by the power amplifier.

[0068] Preferably, the data acquisition unit converts the received electrical signal into a digital signal and then sends it to the control unit, comprising:

[0069] The measuring probe of the data acquisition unit collects fast transient electrical signals such as gate voltage, current, cathode voltage, and current of the thyristor module to be tested;

[0070] After receiving the fast transient electrical signal output by the measuring probe, the acquisition card of the data acquisition unit converts the fast transient electrical signal into a digital signal and transmits it to the control unit.

[0071] Preferably, the measuring probe of the data acquisition unit acquires the electrical signal output by the thyristor module to be tested, including acquiring a voltage signal and a current signal.

[0072] Preferably, the control unit performs signal analysis based on the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and determines the performance index of the thyristor module to be tested. The control unit adopts NI's PXIe controller, which is combined with an adapted acquisition card, and uses a targeted signal acquisition and signal processing program developed in the NI Labview environment to analyze and extract electrical signals.

[0073] Preferably, the characteristic quantities of the thyristor module to be tested include gate current rising rate, gate voltage rising rate, trigger time, turn-off time, recovery voltage amplitude, recovery voltage rising rate and triggerable phase interval.

[0074] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A system for testing the performance of a hybrid on-load tap-changer thyristor module, characterized in that: The system comprises: A current source unit, which is connected to the control unit and the thyristor module to be tested respectively, and is used to apply current to the thyristor module to be tested after receiving an instruction from the control unit; A control unit, which is connected to the current source unit and the data acquisition unit respectively, and is used to perform signal analysis according to the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and control the current source unit to apply current to the thyristor module to be tested; The data acquisition unit is connected to the current source unit, the thyristor module to be tested and the control unit respectively, and is used for acquiring the electrical signals output by the thyristor module to be tested and the current source unit. The trigger source unit is connected to the current source unit and the thyristor module to be tested respectively, and is used to control the trigger source unit to apply a given trigger waveform to the thyristor module to be tested after detecting the phase of the output current of the current source unit.

2. The system according to claim 1, characterized in that The current source unit is a hysteresis-controlled current source, and includes a three-phase power supply, a rectifier circuit, a single-phase inverter H-bridge, an isolation transformer and a capacitor group connected in sequence. After the 380V three-phase power supply is rectified by the rectifier circuit, the single-phase inverter H-bridge outputs a current waveform of a specified amplitude according to the instruction issued by the control unit, and after passing through the isolation transformer, the voltage of the current source unit is supported by the capacitor group and output to the thyristor module to be tested.

3. The system according to claim 1, characterized in that The data acquisition unit includes a measuring probe and an acquisition card, wherein the measuring probe is connected to the current source unit, the thyristor module to be tested and the acquisition card respectively, and is used to collect the electrical signals output by the current source unit and the thyristor module to be tested, and send them to the acquisition card, and the acquisition card is used to convert the received electrical signals into digital signals and transmit them to the control unit.

4. The system according to claim 1 or 2, characterized in that: The control unit includes a main controller and a control board, wherein the control board is connected to the current source unit, and the main controller is connected to the data acquisition unit.

5. The system according to claim 4, characterized in that The trigger source unit includes a phase-locked loop, an arbitrary waveform generator and a power amplifier connected in sequence. The phase-locked loop is connected to the current source unit to collect the phase of the output current of the current source unit to provide an output phase reference for the arbitrary waveform generator. The power amplifier amplifies the trigger signal generated by the arbitrary waveform generator and applies it to the thyristor module to be tested.

6. The system according to claim 2, characterized in that For the current source unit, in each power frequency cycle of its output current waveform, the output voltage of the arbitrary waveform generator in the trigger source unit is u f , Among them, u f represents the output voltage of the arbitrary waveform generator, t represents time, Δt, K1, K2, α1, α2 are a series of process coefficients, R is the equivalent resistance of the entire thyristor module, C is the equivalent resistance of the entire thyristor module, L is the equivalent inductance of the entire thyristor module, R s is the residual resistance of the mechanical contacts connected in parallel with the thyristor module in the hybrid on-load tapchanger after arcing, U m It represents the maximum recovery voltage generated by the mechanical contacts connected in parallel with the thyristor module in the hybrid on-load tapchanger after arcing, U s It indicates the recovery voltage of the mechanical contact connected in parallel with the thyristor module in the hybrid on-load tap-changer at the current zero crossing point after arcing. It indicates that the phase-locked loop recognizes the instantaneous value of the phase of the output current waveform of the current source unit.

7. A method for testing the performance of a hybrid on-load tap changer thyristor module as claimed in claim 1, characterized in that: The method comprises: The current source unit applies current to the thyristor module to be tested; The trigger source unit identifies the output phase of the current source unit and applies a specific trigger signal to the gate of the thyristor module to be tested at different phases; The data acquisition unit collects the gate and cathode electrical signals of the thyristor module to be tested; The data acquisition unit converts the received electrical signal into a digital signal and sends it to the control unit; The control unit performs signal analysis according to the information sent by the data acquisition unit to extract the characteristic quantity of the thyristor module to be tested, and determines the performance of the thyristor module to be tested.

8. The method according to claim 7, characterized in that The current source unit applies current to the thyristor module to be tested, comprising: After the 380V three-phase power supply in the current source unit is rectified by the rectifier circuit, the single-phase inverter H-bridge outputs a current waveform of a specified amplitude according to the instruction issued by the control unit. After passing through the isolation transformer, the voltage of the current source unit is supported by the capacitor group and output to the thyristor module to be tested.

9. The method according to claim 7 or 8, characterized in that: The trigger source unit identifies the output phase of the current source unit and applies specific trigger signals to the gate of the thyristor module to be tested at different phases, including: The phase-locked loop in the trigger source unit identifies the phase of the output current of the current source unit, controls the arbitrary waveform generator to output a trigger signal according to a given formula at different phases with a set step size, and outputs the trigger signal to the gate of the thyristor module to be tested after being amplified by the power amplifier.

10. The method according to claim 7, characterized in that The characteristic quantities of the thyristor module to be tested include gate current rising rate, gate voltage rising rate, trigger time, turn-off time, recovery voltage amplitude, recovery voltage rising rate and triggerable phase interval.

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