阅读说明：本技术 一种柔直换流阀用旁路晶闸管触发单元及控制方法 (Bypass thyristor trigger unit for flexible direct-current converter valve and control method ) 是由 张娟 崔斌 杨山河 孙小平 娄彦涛 于 2021-08-24 设计创作，主要内容包括：一种柔直换流阀用旁路晶闸管触发单元及控制方法,触发单元包括通过光纤与柔直换流阀子模块控制板连接的光收发器,光收发器的光接收和光发射通信采用同一个接口,光收发器的光接收端连接脉冲发生器,脉冲发生器输出固定脉冲宽度的触发波形信号给门极脉冲放大模块,门极脉冲放大模块用于对门极脉冲进行功率放大,门极脉冲放大模块经过门极连接器连接旁路晶闸管,旁路晶闸管与柔直换流阀子模块之间反并联连接；光收发器的光发射端经过取能模块连接电源连接器,取能模块设置隔离变压器实现取能部分与门极触发部分的电压隔离。本发明能够降低电磁干扰对子模块控制板的影响,降低运维难度及运维成本,提高柔直换流阀子模块的运行可靠性。(A trigger unit comprises an optical transceiver connected with a flexible-direct converter valve submodule control panel through an optical fiber, the optical receiving and optical transmitting communication of the optical transceiver adopt the same interface, the optical receiving end of the optical transceiver is connected with a pulse generator, the pulse generator outputs a trigger waveform signal with fixed pulse width to a gate pulse amplification module, the gate pulse amplification module is used for carrying out power amplification on gate pulse, the gate pulse amplification module is connected with a bypass thyristor through a gate connector, and the bypass thyristor is connected with the flexible-direct converter valve submodule in an anti-parallel mode; the light emitting end of the optical transceiver is connected with the power connector through the energy taking module, and the energy taking module is provided with an isolation transformer to realize voltage isolation between the energy taking part and the gate pole triggering part. The invention can reduce the influence of electromagnetic interference on the submodule control board, reduce the operation and maintenance difficulty and the operation and maintenance cost and improve the operation reliability of the submodule of the flexible-straight converter valve.)

1. The utility model provides a bypass thyristor trigger unit for flexible direct current valve which characterized in that: the optical transceiver (2) is connected with a flexible direct current converter valve submodule control panel through an optical fiber, the optical receiving and optical transmitting communication of the optical transceiver (2) adopts the same interface, an optical receiving end (4) of the optical transceiver (2) is connected with a pulse generator (6), the pulse generator (6) outputs a trigger waveform signal with fixed pulse width to a gate pulse amplification module (7), the gate pulse amplification module (7) is used for carrying out power amplification on gate pulse, the gate pulse amplification module (7) is connected with a bypass thyristor through a gate connector (9), and the bypass thyristor is connected with the flexible direct current converter valve submodule in an anti-parallel mode; the light emitting end (5) of the light transceiver (2) is connected with the power connector (1) through the energy taking module (3), and the energy taking module (3) is provided with an isolation transformer to realize voltage isolation of the energy taking part and the gate pole triggering part.

2. The bypass thyristor trigger unit for a flexible direct current valve according to claim 1, wherein: an under-voltage detection module (8) is arranged between a light emitting end (5) of the optical transceiver (2) and the energy taking module (3), the under-voltage detection module (8) can detect the voltage of the energy taking part in real time and compare the voltage with a set voltage threshold, and when the voltage of the energy taking part is smaller than the set voltage threshold, the bypass thyristor can send a return signal to the flexible direct current converter valve sub-module control board.

3. The bypass thyristor trigger unit for a flexible direct current valve according to claim 1, wherein: the optical transceiver (2) and the flexible straight converter valve submodule control board are connected in an inserted mode through bare fibers and locked and fixed without connectors.

4. The bypass thyristor trigger unit for a flexible direct current valve according to claim 1, wherein: the pulse generator (6) is designed by adopting a monostable circuit, a programmable logic device is not configured, and timing is carried out by adopting a resistance-capacitance device.

5. The bypass thyristor trigger unit for a flexible direct current valve according to claim 1, wherein: the power supply connector (1) supplies power through a high-potential energy-taking power supply of the flexible-direct converter valve submodule.

6. The bypass thyristor trigger unit for a flexible direct current valve according to claim 1, wherein: the bypass thyristor is reversely broken down under the condition of overvoltage fault to bypass the flexible-straight converter valve submodule, and the bypass thyristor is forwardly turned under the condition of overcurrent fault to shunt a freewheeling diode in the flexible-straight converter valve submodule.

7. A control method of a bypass thyristor triggering unit for a flexible direct current valve according to any one of claims 1 to 5, characterized by comprising the steps of: the optical transceiver (2) is communicated with a flexible-straight converter valve submodule control panel through an optical fiber, the flexible-straight converter valve submodule control panel issues a control instruction, firstly, a pulse generator (6) generates a trigger waveform signal with a fixed pulse width and sends the trigger waveform signal to a gate pole pulse amplification module (7), the gate pole pulse amplification module (7) amplifies the power of gate pole pulse, and the gate pole pulse after power amplification is sent to a gate pole of a bypass thyristor through a gate pole connector (9) to enable the bypass thyristor to be conducted.

8. The control method according to claim 7, characterized in that: the bypass thyristor is powered by a high-potential energy taking power supply of the flexible direct converter valve submodule, an energy taking part is isolated from the voltage of the gate electrode triggering part through an isolation transformer of the energy taking module (3), an under-voltage detection threshold value is set on the under-voltage detection module (8), the voltage of the energy taking part is detected in real time by the under-voltage detection module (8) and compared with the set voltage threshold value, and when the voltage of the energy taking part is smaller than the set voltage threshold value, the bypass thyristor triggering unit can send a return signal to the flexible direct converter valve submodule control plate to feed back the fault condition.

Technical Field

The invention belongs to the technical field of flexible direct current transmission, and particularly relates to a bypass thyristor trigger unit for a flexible direct current converter valve and a control method.

Background

At present, a plurality of flexible direct current converter valve projects all adopt bypass thyristors as overvoltage protection devices of submodules, the bypass thyristors are connected in an anti-parallel mode at a power supply input port of the submodules, and work projects of the flexible direct current converter valve projects are controlled by a bypass thyristor trigger unit. When the sub-module has overvoltage faults, the bypass thyristor is reversely broken down and is in a short-circuit state, and the sub-module is bypassed from the main loop; when the submodule has an overcurrent fault, the bypass thyristor receives a trigger command of the bypass thyristor trigger unit to conduct in the forward direction, so that the current of the fly-wheel diode is shunted, and the fly-wheel diode is protected from overcurrent breakdown. At present, the bypass thyristor trigger units used in engineering are all integrated on a submodule control panel, the working logic of the bypass thyristor trigger units is controlled by an FPGA on the submodule control panel, an isolation transformer is adopted for energy transmission, and the secondary side of the isolation transformer is connected to a bypass thyristor through a cable so as to trigger the conduction of the thyristor. The mode leads the electric connection to the sub-module control board, and the normal work of the sub-module control board is influenced by the electromagnetic interference easily occurring in the operation process.

Disclosure of Invention

The invention aims to solve the problems in the prior art, and provides a bypass thyristor trigger unit for a flexible direct current converter valve and a control method thereof, so that the influence of electromagnetic interference on a submodule control board is reduced, the operation and maintenance difficulty and the operation and maintenance cost are reduced, and the operation reliability of the flexible direct current converter valve submodule is improved.

In order to achieve the purpose, the invention has the following technical scheme:

a bypass thyristor trigger unit for a flexible-direct converter valve comprises an optical transceiver connected with a flexible-direct converter valve submodule control panel through an optical fiber, wherein the optical receiving and optical transmitting communication of the optical transceiver adopts the same interface, the optical receiving end of the optical transceiver is connected with a pulse generator, the pulse generator outputs a trigger waveform signal with fixed pulse width to a gate pulse amplification module, the gate pulse amplification module is used for carrying out power amplification on gate pulse, the gate pulse amplification module is connected with a bypass thyristor through a gate connector, and the bypass thyristor is connected with the flexible-direct converter valve submodule in an anti-parallel mode; the light emitting end of the optical transceiver is connected with the power connector through the energy taking module, and the energy taking module is provided with an isolation transformer to realize voltage isolation between the energy taking part and the gate pole triggering part.

As a preferred embodiment of the bypass thyristor trigger unit for the flexible-direct converter valve, an under-voltage detection module is disposed between the light emitting end of the light transceiver and the energy-taking module, the under-voltage detection module can detect the voltage of the energy-taking part in real time and compare the detected voltage with a set voltage threshold, and when the voltage of the energy-taking part is smaller than the set voltage threshold, the bypass thyristor sends a return signal to the flexible-direct converter valve sub-module control board.

As a preferred scheme of the bypass thyristor trigger unit for the flexible-direct converter valve, the optical transceiver and the flexible-direct converter valve submodule control board are connected in a bare fiber insertion mode and locked and fixed, and a connector is not needed.

As a preferable scheme of the bypass thyristor trigger unit for the flexible direct current valve, the pulse generator is designed by adopting a monostable circuit, a programmable logic device is not configured, and only a resistance-capacitance device is adopted for timing.

As a preferable scheme of the bypass thyristor triggering unit for the flexible direct current converter valve, the power supply connector supplies power through a high-potential energy-taking power supply of the flexible direct current converter valve submodule.

As a preferred scheme of the bypass thyristor triggering unit for the flexible-direct converter valve, the bypass thyristor is reversely broken down under the condition of overvoltage fault to bypass the flexible-direct converter valve submodule, and the bypass thyristor is forwardly turned under the condition of overcurrent fault to shunt the freewheeling diode in the flexible-direct converter valve submodule.

The invention also provides a control method of the bypass thyristor trigger unit for the flexible direct current converter valve, which comprises the following steps:

the optical transceiver is communicated with the flexible-straight converter valve submodule control panel through an optical fiber, the flexible-straight converter valve submodule control panel issues a control instruction, the pulse generator generates a trigger waveform signal with a fixed pulse width and sends the trigger waveform signal to the gate pole pulse amplification module, the gate pole pulse amplification module performs power amplification on the gate pole pulse, and the gate pole pulse after power amplification is sent to the gate pole of the bypass thyristor through the gate pole connector so that the bypass thyristor is conducted.

As a preferred scheme of the control method of the present invention, the bypass thyristor is powered by a high-potential energy-taking power supply of the flexible-straight converter valve submodule, the energy-taking part is isolated from the voltage of the gate electrode triggering part by an isolation transformer of the energy-taking module, an under-voltage detection threshold is set on the under-voltage detection module, the voltage of the energy-taking part is detected in real time by the under-voltage detection module and compared with the set voltage threshold, and when the voltage of the energy-taking part is smaller than the set voltage threshold, the bypass thyristor triggering unit sends a return signal to the flexible-straight converter valve submodule control board to feed back the fault condition.

Compared with the prior art, the invention has the following beneficial effects: in the past, a bypass thyristor is generally integrated on a control board of a submodule of the flexible-straight converter valve as a last-stage bypass mode after the bypass switch fails, so that the influence of an electromagnetic environment is easily caused, and the stable operation of the converter valve is not facilitated. The bypass thyristor trigger unit for the flexible direct current converter valve is of a discrete structure, communication with the submodule control panel is carried out through optical fibers, the integration level of the submodule control panel can be greatly reduced, meanwhile, the influence of electromagnetic interference on the submodule control panel is reduced, if the bypass thyristor trigger unit breaks down, only corresponding parts need to be replaced, the submodule control panel does not need to be replaced, and operation and maintenance difficulty and operation and maintenance cost can be greatly reduced. The traditional bypass thyristor trigger unit is integrated on a flexible direct current converter valve submodule control board, a pulse transformer is adopted for isolation, the inductance of the pulse transformer can inhibit the current rise rate of trigger pulse, and the energy taking unit is provided with the isolation transformer, so that the gate trigger pulse is not influenced by the inductance of the transformer, and the reliable conduction of the bypass thyristor can be ensured.

Furthermore, the energy taking module is provided with an under-voltage detection module, the voltage of the energy taking part can be detected in real time through the under-voltage detection module and compared with the set voltage threshold, and when the voltage of the energy taking part is smaller than the set voltage threshold, the bypass thyristor can send a return signal to the flexible direct current converter valve sub-module control board to timely know the fault condition.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a bypass thyristor trigger unit for the flexible direct current converter valve;

in the drawings: 1-a power supply connector; 2-an optical transceiver; 3-an energy obtaining module; 4-a light receiving end; 5-a light emitting end; 6-a pulse generator; 7-gate pulse amplification module; 8-an undervoltage detection module; 9-gate connector.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention.

Referring to fig. 1, the invention provides a bypass thyristor trigger unit for a flexible-direct converter valve, which comprises an optical transceiver 2 connected with a flexible-direct converter valve sub-module control board through an optical fiber, wherein the optical transceiver 2 adopts the same interface for optical receiving and optical transmitting communication, the optical transceiver 2 and the flexible-direct converter valve sub-module control board can be connected in a bare fiber insertion mode and locked and fixed, a connector is not needed for optical fiber connection, and the cost and the use space can be greatly saved. The light receiving end 4 of the optical transceiver 2 is connected with a pulse generator 6, the pulse generator 6 outputs a trigger waveform signal with a fixed pulse width to a gate pulse amplification module 7, the pulse generator 6 is designed by adopting a monostable circuit, a programmable logic device is not required to be configured, timing is carried out only by adopting a resistance-capacitance device, the gate pulse amplification module 7 is used for carrying out power amplification on gate pulse so as to fully and reliably trigger a thyristor to be conducted, the gate pulse amplification module 7 is connected with a bypass thyristor through a gate connector 9, and the bypass thyristor is connected with a flexible direct current converter submodule in an anti-parallel mode. The bypass thyristor is reversely broken down under the condition of overvoltage fault to bypass the flexible-straight converter valve submodule, and forward turning under the condition of overcurrent fault to shunt the freewheeling diode in the flexible-straight converter valve submodule. The light emitting end 5 of the optical transceiver 2 is connected with the power connector 1 through the energy taking module 3, and the energy taking module 3 is provided with an isolation transformer to realize voltage isolation between the energy taking part and the gate pole triggering part. An under-voltage detection module 8 is arranged between the light emitting end 5 of the optical transceiver 2 and the energy-taking module 3, the under-voltage detection module 8 can detect the voltage of the energy-taking part in real time and compare the voltage with the set voltage threshold, and when the voltage of the energy-taking part is smaller than the set voltage threshold, the bypass thyristor trigger unit can send a return signal to the flexible direct converter valve submodule control board.

The invention relates to a control method of a bypass thyristor trigger unit for a flexible direct current converter valve, which comprises the following steps:

the optical transceiver 2 communicates with a flexible-straight converter valve submodule control panel through an optical fiber, the flexible-straight converter valve submodule control panel issues a control instruction, firstly, a pulse generator 6 generates a trigger waveform signal with a fixed pulse width and sends the trigger waveform signal to a gate pole pulse amplification module 7, the gate pole pulse amplification module 7 amplifies the power of gate pole pulses, and the gate pole pulses after power amplification are sent to a gate pole of a bypass thyristor through a gate pole connector 9 to enable the bypass thyristor to be conducted. The bypass thyristor is powered by a high-potential energy taking power supply of the flexible direct current converter valve submodule, an energy taking part is isolated from the voltage of the gate electrode triggering part through an isolation transformer of the energy taking module 3, an under-voltage detection threshold value is set on the under-voltage detection module 8, the voltage of the energy taking part is detected in real time by the under-voltage detection module 8 and compared with the set voltage threshold value, and when the voltage of the energy taking part is smaller than the set voltage threshold value, the bypass thyristor triggering unit can send a return signal to the flexible direct current converter valve submodule control plate to feed back the fault condition.

The bypass thyristor is supplied with power by a high-potential energy-taking power supply in the flexible-straight converter valve submodule, the grounding point of the bypass thyristor is the negative end of a high-voltage capacitor of the flexible-straight converter valve submodule, the bypass thyristor is connected in the flexible-straight converter valve submodule in an anti-parallel mode, the cathode of the bypass thyristor is positioned at the collector electrode of a lower tube in the flexible-straight converter valve submodule, and when the flexible-straight converter valve submodule is in a working state, a higher potential difference exists between the flexible-straight converter valve submodule and the collector electrode, so that the energy-taking part and the gate pole triggering part are isolated by arranging an isolation power supply.

While the invention has been described above with reference to specific features and embodiments thereof, it will be apparent that various modifications and combinations can be made therein without departing from the spirit and scope of the invention. Accordingly, the contents of the above specification and drawings are merely illustrative of the invention as defined by the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. It is apparent that those skilled in the art can make various modifications and variations to the present invention, which also fall within the scope of the claims of the present invention and their equivalents.