A kind of thyristor shunt detection circuit and detection method for voltage source converter
Technical field:
The present invention relates to a kind of thyristor shunt detection circuit and detection methods, in particular to a kind of to be used for half-bridge structure
The thyristor shunt detection circuit and detection method of voltage source converter.
Background technique:
Thyristor device is a kind of high voltage, powerful power semiconductor, it has, and capacity is big, high-efficient and control
The advantages that property processed is good, is widely used in the circuits such as rectification, inversion, copped wave and the switch to electric energy, is that information industry and tradition produce
Important interface between industry is the bridge between vulnerabilities scan and forceful electric power controlled device.
With the development of power electronics technology, based on as the device for high-power power electronic of the core component of HVDC
The operational reliability of high-pressure series valve and the survival ability under various POWER SYSTEM STATEs are increasingly becoming one and are related to HVDC
The critical issue that can be used widely in the power system.In order to improve the reliability of thyristor, have been carried out a large amount of
Theoretical research work, but complete test is still raising and the final technological means for guaranteeing Thyristors in series valve reliability.
Overcurrent test be check valve in case of a fault, the ability of tolerance overcurrent, voltage and its related fuel factor.This
Application reliable triggering thyristor for how in case of a fault, and investigate thyristor tolerance high current ability.
Summary of the invention:
The object of the present invention is to provide a kind of thyristor shunt detection circuit and detection method for voltage source converter,
The present invention can satisfy the requirement to examining half-bridge voltage source inverter thyristor to flow through dash current ability.
To achieve the above object, the present invention uses following technical scheme:A kind of thyristor for voltage source converter point
Current detection circuit, the circuit include sequentially connected experiment power supply, DC power supply, charging circuit and change respectively with voltage source
Flow the resonant tank that the thyristor tested device of device is connected with ground connection discharge loop.
A kind of thyristor shunt for half-bridge structure voltage source converter provided by the invention protects circuit, the test
Power supply includes low-pressure single-phase alternating current power supply or low-voltage three-phase AC power supply and the circuit breaker Q Z that connect with the power supply.
A kind of thyristor shunt detection circuit for voltage source converter provided by the invention, the DC power supply include
Pressure regulator, transformer and the uncontrollable rectifier bridge being sequentially connected in series with the experiment power supply;The uncontrollable rectifier bridge is single-phase whole
Flow bridge or three-phase rectification bridge.
Another preferred a kind of thyristor shunt detection circuit for voltage source converter provided by the invention, it is described to fill
Circuit includes the charging resistor R1 and switch K1 being sequentially connected in series with the uncontrollable rectifier bridge output end.
Another preferred a kind of thyristor shunt detection circuit for voltage source converter provided by the invention, it is described humorous
Vibration circuit include the capacitor C in parallel with the charge circuit, and the sequentially connected inductance L in described charging circuit one end, resistance R2,
Thyristor and switch K2;The thyristor is to have greater than tested device thyristor I2T value and be greater than tested device thyristor pressure resistance
Value;
The charging circuit is used to control the charging time of the capacitor C.
Another preferred a kind of thyristor shunt detection circuit for voltage source converter provided by the invention, the quilt
Examination equipment includes the half-bridge voltage source inverter with the thyristor reverse parallel connection in the discharge loop, and the half-bridge voltage source is changed
Stream device includes the half-bridge bridge arm that 2 IGBT are composed in series down tube, every IGBT and freewheeling diode reverse parallel connection;
Parallel connection direct capacitor between upper tube IGBT collector and down tube IGBT emitter, half-bridge bridge arm midpoint is under
Submodule bypass thyristor in parallel between pipe IGBT emitter;The half-bridge bridge arm connects controller.
Another preferred a kind of thyristor shunt detection circuit for voltage source converter provided by the invention, it is described to connect
Ground discharge loop include the switch K3 being connect with the capacitor C anode and with the concatenated discharge resistance R3 of the switch K3 and described
Discharge resistance R3 ground connection.
A kind of detection method of detection circuit comprising above-mentioned technical proposal provided by the invention, it is characterised in that:Including
Following steps:
(1) the switch K of resonant tank is disconnected2With the switch K of ground connection discharge loop3, upper down tube IGBT is off always
State, the thyristor bypassed in thyristor and resonant tank are all constantly in triggering state;
(2) breaker of experiment power supply and the switch K of charging circuit are closed1;
(3) pressure regulator is adjusted, DC bus-bar voltage is made to reach requirement and charge for the capacitor C of resonant tank;
(4) after charging reaches stable, the breaker of open test power supply and the switch K of charging circuit1;
(5) it is closed the switch K of resonant tank2;
A kind of detection method provided by the invention, the step (1) are powered on by half-bridge voltage source Converter controller, are enabled
It generates trigger pulse, makes the brilliant lock in down tube IGBT in an off state always, bypass thyristor and charging and discharging circuit
Pipe is all constantly in triggering state.
A kind of detection method provided by the invention, after detection, the switch K of closure ground connection discharge loop3, returned to resonance
After capacitor C in road is substantially discharged, it is whether intact that each device in each thyristor and half-bridge voltage source inverter is detected respectively.
Compared with the nearest prior art, the technical scheme provide by that invention has the following excellent effect
1, experimental rig structure of the invention is simple, and test method is simple and reliable;
2, power supply capacity needed for test of the invention is smaller;
3, the present invention can construct great dash current using lesser capacitance at lower voltages;
4, the present invention can simulate the failure of flexible direct current DC bus short circuit after UPFC, meet to inspection half-bridge voltage source
Inverter thyristor flows through the requirement of dash current ability;
5, the half-bridge voltage source inverter in the present invention is for examining dash current whether sub- module bypass thyristor
Generate adverse effect;
6, ground connection discharge loop after test for making capacitor C discharge, guarantee test safety.
Detailed description of the invention
Fig. 1 is electrical block diagram of the invention.
Specific embodiment
Below with reference to embodiment, the invention will be described in further detail.
Embodiment 1:
As shown in Figure 1, thyristor shunt protection circuit of the invention of this example for half-bridge structure voltage source converter includes
Sequentially connected experiment power supply, DC power supply, charging circuit, resonant tank and tested device;The resonant tank is put with ground connection
Electrical circuit connection.
The experiment power supply includes low-pressure single-phase alternating current power supply or low-voltage three-phase AC power supply and connect with the power supply
Breaker.
The DC power supply includes the pressure regulator, transformer and uncontrollable rectifier being sequentially connected in series with the experiment power supply
Bridge;The uncontrollable rectifier bridge is single-phase rectification bridge or three-phase rectification bridge.
The charging circuit includes the charging resistor R1 and switch being sequentially connected in series with the uncontrollable rectifier bridge output end
K1。
The resonant tank includes the capacitor C in parallel with the charge circuit, is sequentially connected with described charging circuit one end
Inductance L, resistance R2, thyristor and switch K2;The thyristor is to have greater than tested device thyristor I2T value and be greater than subject
Equipment thyristor pressure voltage, the charging circuit are used to control the charging time of capacitor C.
The tested device includes the half-bridge voltage source inverter with the thyristor reverse parallel connection in the discharge loop, institute
Stating half-bridge voltage source inverter includes the half-bridge bridge arm that 2 IGBT are composed in series down tube, every IGBT and two pole of afterflow
Pipe reverse parallel connection;
Parallel connection direct capacitor between upper tube IGBT collector and down tube IGBT emitter, half-bridge bridge arm midpoint is under
Submodule bypass thyristor in parallel between pipe IGBT emitter;The half-bridge bridge arm connects controller.
The ground connection discharge loop include the switch K3 being connect with the capacitor C anode and with the switch K3 is concatenated puts
Resistance R3 and discharge resistance R3 ground connection.
The detection method of circuit comprising above-mentioned technical proposal is:
1) the switch K of resonant tank is disconnected2, ground connection discharge loop switch K3, on the Converter controller of half-bridge voltage source
Electricity enables it generate trigger pulse, keeps down tube IGBT in an off state always, makes to bypass in thyristor and resonant tank
Thyristor is all constantly in triggering state;
2) the circuit breaker Q Z of experiment power supply and the switch K of charging circuit are closed1;
3) pressure regulator is adjusted, DC bus-bar voltage is made to reach requirement, is charged to the capacitor C of resonant tank;
4) after charging reaches stable, the circuit breaker Q Z of open test power supply and the switch K of charging circuit1;
5) it is closed the switch K of resonant tank2, test starts;
6) after being completed, the switch K of closure ground connection discharge loop3, after capacitor is substantially discharged, all crystalline substances are detected respectively
Whether each device is intact in brake tube and half-bridge voltage source inverter.
Wherein, resonant tank is for generating dash current, and thyristor is for examining the ability for flowing through dash current, half-bridge electricity
Source Con-verters are for examining whether dash current can generate adverse effect to sub- module bypass thyristor.
Finally it should be noted that:The above embodiments are merely illustrative of the technical scheme of the present invention and are not intended to be limiting thereof, to the greatest extent
Pipe is described the invention in detail referring to above-described embodiment, those of ordinary skills in the art should understand that:Still may be used
With modifications or equivalent substitutions are made to specific embodiments of the invention, and repaired without departing from any of spirit and scope of the invention
Change or equivalent replacement, should all cover in present claims range.