A method and system for detecting a back-check signal of a converter valve module

Abstract

The application belongs to the technical field of electrical equipment of power systems, and particularly relates to a method and system for detecting a back-check signal of a converter valve module. When the converter valve starts to work, the method triggers a high potential plate of the converter valve to output a first back-check signal, which is transmitted to a main back-check signal detection board card to determine whether the first back-check signal is abnormal. The high potential plate is triggered to output a second back-check signal, which is transmitted to an auxiliary back-check signal detection board card to determine whether the second back-check signal is abnormal. When at least one of the first back-check signal and the second back-check signal of the same high potential plate is abnormal, the high potential plate is faulty. The two back-check signals are output by the high potential plate, and the same high potential plate is detected by two detection branches, so that the possibility that an abnormal signal is detected as a normal signal is avoided, the redundancy of the back-check signal detection loop of the converter valve is realized, and the reliability of the operation of the converter valve is improved.

Description

Technical Field

[0001] This invention belongs to the field of electrical equipment technology for power systems, and specifically relates to a method and system for detecting feedback signals of a converter valve module. Background Technology

[0002] Currently, ultra-high voltage direct current (UHVDC) transmission, as a key technology for the "West-to-East Power Transmission" project, boasts advantages such as low transmission loss and narrow corridor width, enabling the transmission of ultra-long-distance, ultra-large-capacity power. The UHVDC converter valve, as a core component of the UHVDC transmission system, directly impacts the system's operational reliability. The feedback signal serves as the basis for valve control equipment to determine the converter valve module's proper functioning. An abnormal signal indicates a module malfunction, and multiple module failures can affect the operation of the entire converter valve.

[0003] The feedback signal transmission circuit of the existing converter valve module is as follows: Figure 1 As shown, the feedback signal is generated by the high-potential board at the converter valve module level and output through its optical port. It is transmitted via fiber optic channel and received by the feedback signal detection board of the valve control device. When the converter valve module malfunctions, the feedback signal detection board of the valve control device detects an abnormality in the feedback signal, thus enabling the valve control device to detect whether the UHV converter valve is malfunctioning. However, existing technology only has one detection loop for each high-potential board of the converter valve module. Therefore, if the transmission path of this detection loop or the device receiving the feedback signal malfunctions, there is a possibility that the abnormal signal may be detected as a normal signal, leading to incorrect feedback signal detection. Consequently, the corresponding converter valve may still be judged as being in a normal state even under abnormal operating conditions. This situation reduces the reliability of the converter valve operation. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for detecting feedback signals of a converter valve module, in order to solve the problem that the existing technology only has one detection circuit for a high-potential board of the converter valve module, which may detect abnormal signals as normal signals, thus reducing the reliability of the converter valve operation.

[0005] To solve the above technical problems, the present invention provides a method for detecting the return signal of a converter valve module, comprising the following steps: 1) When the converter valve starts working, the valve control equipment corresponding to the converter valve sends a start detection signal to the converter valve; 2) Upon receiving the start detection signal, the first optical emission port of the high potential board triggering the converter valve outputs the first return detection signal and transmits it to the main return detection signal detection board corresponding to the high potential board to determine whether the received first return detection signal is abnormal. Upon receiving the start detection signal, the second optical emission port of the high-potential board is triggered to output the second return detection signal, which is then transmitted to the auxiliary return detection signal detection board corresponding to the high-potential board to determine whether the received second return detection signal is abnormal. The first and second return detection signals are generated by the voltage detection module based on the module terminal voltage. 3) If at least one of the first and second return signals of the same high-potential board is abnormal, then the high-potential board is faulty.

[0006] Its beneficial effects are as follows: When the converter valve is working, the present invention triggers the high-potential board of the converter valve to send two return detection signals. One signal is used by the main return detection signal detection board to determine whether the high-potential board is faulty, and the other signal is used by the auxiliary return detection signal detection board to determine whether the high-potential board is faulty. When there is an abnormality in the detection results of the two return detection signals, the high-potential board that issued the abnormal return detection signal is determined to be faulty. Compared with the existing method for detecting return detection signals, the present invention provides an additional detection branch for a high-potential board. Therefore, when an abnormal condition exists in one detection branch, causing the abnormal state of the return detection signal to be unidentified, the other detection branch can detect it. This avoids the possibility of detecting an abnormal signal as a normal signal when there is only one detection branch, thereby realizing redundancy in the return detection signal detection circuit of the converter valve and improving the reliability of the converter valve operation.

[0007] Furthermore, in step 2), after receiving the start detection signal, the second optical emission ports of different high-potential plates in the valve assembly of the same converter valve output second return detection signals of different phases.

[0008] In the same valve assembly, there are multiple high-potential plates. By outputting a second return detection signal with a different phase from the second optical emission port of each high-potential plate, the auxiliary return detection signal detection board can determine which high-potential plate emitted the return detection signal based on the phase of the return detection signal after receiving the return detection signal. In turn, when there is an abnormal return detection signal, the origin of the abnormal return detection signal can be accurately determined.

[0009] Furthermore, by delaying the signal generated by the module terminal voltage according to the different high-potential plates in the valve assembly of the same converter valve, a second feedback signal with different phases is obtained.

[0010] Since the delay time of the delay output of different high potential plates of the same valve assembly is different, a second feedback signal with different phase can be obtained, and the output terminal can be accurately determined based on the second feedback signal.

[0011] Further, in step 2), the process of transmitting the signal to the auxiliary return check signal detection board corresponding to the high potential board is as follows: the second return check signal emitted by each high potential board in the valve assembly of the same converter valve is first transmitted to the corresponding input port of the optical distributor, and then transmitted from one output port of the optical distributor to the corresponding receiving channel of the auxiliary return check signal detection board.

[0012] The input ports of the optical splitter correspond one-to-one with the high-potential boards of the same valve assembly, and one output port of the optical splitter corresponds to one receiving channel of the auxiliary return check signal detection board. When a signal is present at one input port of the optical splitter, this signal is output at the output port. The invention incorporates a second return check signal with different phases based on delay output (i.e., the auxiliary return check signal input to the optical splitter is a second return check signal with different delays for different high-potential boards). Therefore, the output port of the optical splitter can output the second return check signals of each high-potential board in a time-division manner. Furthermore, since one output port of the optical splitter corresponds to one receiving channel of the auxiliary return check signal detection board, and one auxiliary return check signal detection board has multiple receiving channels, one auxiliary return check signal detection board can detect the return check signals of multiple valve assemblies, thus reducing the number of auxiliary return check signal detection boards required.

[0013] Furthermore, by having different high-potential plates in the valve assembly of the same converter valve all receive the same trigger signal from the valve control device, and using this signal as the trigger signal to start the delay output timing, different high-potential plates in the valve assembly of the same converter valve can perform corresponding delay outputs.

[0014] Each high-potential plate in a valve assembly is triggered based on the same trigger signal, ensuring that the first feedback signal can be generated simultaneously. This signal also serves as the trigger signal for the delay timing, ensuring that the timing reference of all high-potential plates is the same, thereby guaranteeing the reliability of the generated second feedback signal.

[0015] To address the aforementioned technical problems, this invention also provides a return signal detection system for a converter valve module, comprising a main return signal detection branch, wherein the main return signal detection branch includes a main return signal detection board, and the receiving channel of the main return signal detection board is used to receive the first optical emission port of each high-potential board in the valve assembly connected to the same converter valve, so as to receive the first return signal output by the first optical emission port of the corresponding high-potential board; it also includes an auxiliary return signal detection branch, wherein the auxiliary return signal detection branch includes an auxiliary return signal detection board, and the receiving channel of the auxiliary return signal detection board is used to receive the second optical emission port of the high-potential board in the valve assembly connected to the converter valve, so as to receive the second return signal output by the second optical emission port of the high-potential board; the first return signal and the second return signal are generated by a voltage detection module based on the module terminal voltage; it also includes a valve control device, wherein the valve control device is used to determine that the high-potential board is faulty when at least one of the first return signal and the second return signal of the same high-potential board is abnormal.

[0016] Its beneficial effects are as follows: When the converter valve is working, the present invention triggers the high-potential board of the converter valve to send two return detection signals. One signal is used by the main return detection signal detection board to determine whether the high-potential board is faulty, and the other signal is used by the auxiliary return detection signal detection board to determine whether the high-potential board is faulty. When there is an abnormality in the detection results of the two return detection signals, the high-potential board that issued the abnormal return detection signal is determined to be faulty. Compared with the existing method for detecting return detection signals, the present invention provides an additional detection branch for a high-potential board. Therefore, when an abnormal condition exists in one detection branch, causing the abnormal state of the return detection signal to be unidentified, the other detection branch can detect it. This avoids the possibility of detecting an abnormal signal as a normal signal when there is only one detection branch, thereby realizing redundancy in the return detection signal detection circuit of the converter valve and improving the reliability of the converter valve operation.

[0017] Furthermore, in the valve assembly of the same converter valve, the second optical emission ports of different high-potential plates output second return detection signals with different phases.

[0018] In the same valve assembly, there are multiple high-potential plates. By outputting a second return detection signal with a different phase from the second optical emission port of each high-potential plate, the auxiliary return detection signal detection board can determine which high-potential plate emitted the return detection signal based on the phase of the return detection signal after receiving the return detection signal. In turn, when there is an abnormal return detection signal, the origin of the abnormal return detection signal can be accurately determined.

[0019] Furthermore, by delaying the signal generated by the module terminal voltage according to the different high-potential plates in the valve assembly of the same converter valve, a second feedback signal with different phases is obtained.

[0020] Since the delay time of the delay output of different high potential plates of the same valve assembly is different, a second feedback signal with different phase can be obtained, and the output terminal can be accurately determined based on the second feedback signal.

[0021] Furthermore, the auxiliary return check signal detection branch also includes an optical splitter. The input port of the optical splitter is used to connect to the second optical emission port of each high-potential board in the valve assembly of the same converter valve, so as to receive the second return check signal output by the second optical emission port of the corresponding high-potential board. One output port of the optical splitter is connected to a receiving channel of the auxiliary return check signal detection board, so as to transmit the second return check signal emitted by each high-potential board in the valve assembly of the same converter valve to the auxiliary return check signal detection board.

[0022] The input ports of the optical splitter correspond one-to-one with the high-potential boards of the same valve assembly, and one output port of the optical splitter corresponds to one receiving channel of the auxiliary return check signal detection board. When a signal is present at one input port of the optical splitter, this signal is output at the output port. The invention incorporates a second return check signal with different phases based on delay output (i.e., the auxiliary return check signal input to the optical splitter is a second return check signal with different delays for different high-potential boards). Therefore, the output port of the optical splitter can output the second return check signals of each high-potential board in a time-division manner. Furthermore, since one output port of the optical splitter corresponds to one receiving channel of the auxiliary return check signal detection board, and one auxiliary return check signal detection board has multiple receiving channels, one auxiliary return check signal detection board can detect the return check signals of multiple valve assemblies, thus reducing the number of auxiliary return check signal detection boards required.

[0023] Furthermore, the valve control device is also used to simultaneously trigger different high-potential plates in the valve assembly of the same converter valve to generate a first feedback signal, and simultaneously trigger the delayed output of the second feedback signal to start timing, so as to realize that different high-potential plates in the valve assembly of the same converter valve perform corresponding delayed outputs.

[0024] Each high-potential plate in a valve assembly is triggered based on the same trigger signal, ensuring that the first feedback signal can be generated simultaneously. This signal also serves as the trigger signal for the delay timing, ensuring that the timing reference of all high-potential plates is the same, thereby guaranteeing the reliability of the generated second feedback signal. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the existing back-check signal transmission loop; Figure 2 This is a schematic diagram of the high potential plate detection principle of the present invention; Figure 3 This is a schematic diagram of the return signal transmission loop of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0027] Example of a return signal detection system for converter valve modules: The return signal detection system of the converter valve module in this embodiment includes a main return signal detection board and an auxiliary return signal detection board. Each high-potential board has two optical emission ports, namely a first optical emission port and a second optical emission port. The first return signal emitted from the first optical emission port is received by the main return signal detection board, and the second return signal emitted from the second optical emission port is received by the auxiliary return signal detection board. For a high-potential board, there are two detection branches to jointly determine whether the high-potential board is faulty. That is, when at least one of the first and second return signals of the same high-potential board is abnormal, the high-potential board is faulty. By using a two-way detection and judgment process for a high-potential board, the possibility of detecting abnormal signals as normal signals, which is possible with only one detection branch, is avoided. This achieves redundancy in the converter valve return signal detection circuit and improves the reliability of converter valve operation.

[0028] Specifically, the system in this embodiment implements the return signal detection process of the converter valve module: like Figure 2 This describes the process of generating a feedback signal for a high-potential board: The voltage detection module generates two feedback signals based on the module's terminal voltage. One feedback signal, the first feedback signal, is directly output through the original optical transmitter (i.e., the first optical transmitter port). The other feedback signal is first transmitted to the logic module. When the logic module receives the feedback signal from the voltage detection module and detects the rising edge of the timing module's signal, it immediately outputs a delayed feedback signal as the second feedback signal. At this time, the second feedback signal output from the newly added optical transmitter port (i.e., the second optical transmitter port) has a fixed time delay T between it and the trigger signal (each timing module has its own fixed T during operation, and different high-potential boards in the same valve assembly have different delays T, meaning that the second optical transmitter ports of different high-potential boards in the same converter valve assembly output second feedback signals with different phases). In this way, feedback signal transmission redundancy is achieved on the high-potential board. In this embodiment, the meeting signal output of the voltage detection module and the timing of the timing module are both based on the triggering of the valve control device. All modules of the same single valve (i.e. the same valve assembly) receive the same trigger signal from the valve control device, and then use this signal as the trigger signal of the timing module. This ensures that all high potential boards of the same single valve can generate the first feedback signal at the same time, while ensuring that the timing reference of all high potential boards is the same, thereby ensuring the reliability of the generated second feedback signal.

[0029] The system connection relationship in this embodiment is as follows: Figure 3 As shown, the converter valve side includes several valve assemblies and an optical splitter, while the valve control device side includes a main return signal detection board and an auxiliary return signal detection board. Each valve assembly includes several high-potential boards, and each high-potential board includes two optical transmission ports. One transmission port is connected to the corresponding receiving channel of the main return signal detection board on the valve control device side to transmit the main return signal to the main return signal detection board. That is, each high-potential board generates a corresponding first return signal, which is transmitted to the optical receiving port of the main return signal detection board in a one-to-one correspondence manner. One main return signal detection board corresponds to the return signal detection of one valve assembly. The other transmission port is connected to the corresponding input port of the optical splitter to transmit the auxiliary return signal to the optical splitter. One output port of the optical splitter is connected to one receiving channel of the auxiliary return signal detection board to transmit the auxiliary return signal generated by the corresponding high-potential board in a time-division multiplexing manner. That is, each optical receiving port of the auxiliary return signal detection board can detect the return signal of one valve assembly. The signal transmission in this embodiment is based on the fiber optic channel transmission process.

[0030] The optical distributor in the valve assembly is an optical element that collects the input signals from the optical receiver ports and outputs them through the output port. That is, as long as a signal is input to a particular optical receiver port, the output port will output the same signal. Therefore, the auxiliary optical transmitter port (i.e., the second optical transmitter port) in the same valve assembly outputs a feedback signal to the optical distributor. By setting different timing lengths for the timing modules on the high-potential boards in different modules, the second feedback signals of each module can be output in a time-division manner at the output port of the optical distributor. After receiving this signal on the valve control device side, the correspondence between each second feedback signal and the converter valve module level can be identified by comparing it with the trigger signal. In other words, the signal at the output end of the optical distributor can be used to identify the correspondence between each signal and the module through phase identification.

[0031] based on Figure 2 The process of generating the return signal from the high-potential plate is shown, and Figure 3 The system connection diagram shown enables the following return signal detection process for the converter valve module: 1) When the converter valve starts working, the valve control equipment corresponding to the converter valve sends a start detection signal to the converter valve; 2) Upon receiving the start detection signal, the first optical emission port of the high potential board triggering the converter valve outputs the first return detection signal and transmits it to the main return detection signal detection board corresponding to the high potential board to determine whether the received first return detection signal is abnormal. Upon receiving the start detection signal, the second optical transmitter of the high potential board is triggered to output the second return detection signal to the optical splitter after a set delay. The output port of the optical splitter transmits the corresponding second return detection signal to the auxiliary return detection signal detection board in a time-division manner to determine whether the received second return detection signal is abnormal. 3) If at least one of the first and second return signals of the same high potential board is abnormal, the high potential board is judged to be faulty.

[0032] This embodiment of the system achieves redundancy in the converter valve module-level return signal detection loop by adding an auxiliary optical emission port to the high-potential plate, adding an optical distributor for each valve assembly on the converter valve side, and adding an auxiliary return signal detection board for each converter valve on the valve control device side. This system configuration requires fewer additional devices compared to existing technologies, making it relatively simple to implement and providing guidance for engineering design.

[0033] Example of a method for detecting the return signal of a converter valve module: The method for detecting the return signal of the converter valve module can be implemented through the return signal detection system of the converter valve module. The return signal detection system of the converter valve module and the process of implementing the return signal detection method of the converter valve module have been described in detail in the embodiment of the return signal detection system of the converter valve module, and will not be repeated here.

[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A method for detecting the feedback signal of a converter valve module, characterized in that, Includes the following steps: 1) When the converter valve starts working, the valve control equipment corresponding to the converter valve sends a start detection signal to the converter valve; 2) Upon receiving the start detection signal, the first optical emission port of the high potential board triggering the converter valve outputs the first return detection signal and transmits it to the main return detection signal detection board corresponding to the high potential board to determine whether the received first return detection signal is abnormal. Upon receiving the start detection signal, the second optical transmitter of the high-potential board is triggered to output the second return detection signal. The second return detection signals emitted by each high-potential board in the valve assembly of the same converter valve are first transmitted to the corresponding input port of the optical splitter, and then transmitted from one output port of the optical splitter to the corresponding receiving channel of the auxiliary return detection signal detection board to determine whether the received second return detection signal is abnormal. The first and second return detection signals are generated by the voltage detection module based on the module terminal voltage. 3) If at least one of the first and second return signals of the same high-potential board is abnormal, then the high-potential board is faulty.

2. The method for detecting the feedback signal of the converter valve module according to claim 1, characterized in that, In step 2), after receiving the start detection signal, the second optical emission ports of different high potential plates in the valve assembly of the same converter valve output second return detection signals with different phases.

3. The method for detecting the return signal of the converter valve module according to claim 2, characterized in that, By delaying the signal generated by the module terminal voltage according to the different high-potential plates in the valve assembly of the same converter valve, a second feedback signal with different phases is obtained.

4. The method for detecting the return signal of the converter valve module according to claim 1, characterized in that, The voltage detection module generates two feedback signals based on the voltage at the module terminal. One feedback signal is directly output through the first optical transmitter port as the first feedback signal. The other feedback signal is first transmitted to the logic module. When the logic module receives the feedback signal from the voltage detection module, it immediately outputs a delayed feedback signal as the second feedback signal through the second optical transmitter port after detecting the rising edge of the signal from the timing module.

5. The method for detecting the return signal of the converter valve module according to claim 4, characterized in that, By having different high-potential plates in the valve assembly of the same converter valve all receive the same trigger signal from the valve control device, and using this signal as the trigger signal to start the delay output timing, different high-potential plates in the valve assembly of the same converter valve can perform corresponding delay outputs.

6. A return signal detection system for a converter valve module, comprising a main return signal detection branch, wherein the main return signal detection branch includes a main return signal detection board, and the receiving channel of the main return signal detection board is used to receive the first optical emission port of each high-potential board in the valve assembly corresponding to the same converter valve, so as to receive the first return signal output from the first optical emission port of the corresponding high-potential board; characterized in that, It also includes an auxiliary return signal detection branch, which comprises an auxiliary return signal detection board and an optical splitter. The input port of the optical splitter is connected to the second optical emission port of each high-potential board in the valve assembly of the same converter valve to receive the second return signal output from the second optical emission port of the corresponding high-potential board. One output port of the optical splitter is connected to a receiving channel of the auxiliary return signal detection board to transmit the second return signal emitted by each high-potential board in the valve assembly of the same converter valve to the auxiliary return signal detection board. The first and second return signals are generated by the voltage detection module based on the module terminal voltage. It also includes a valve control device, which is used to determine that the high-potential board is faulty when at least one of the first and second return signals of the same high-potential board is abnormal.

7. The feedback signal detection system for the converter valve module according to claim 6, characterized in that, In the valve assembly of the same converter valve, the second optical emission port of different high potential plates outputs a second feedback signal with different phases.

8. The feedback signal detection system for the converter valve module according to claim 7, characterized in that, By delaying the signal generated by the module terminal voltage according to the different high-potential plates in the valve assembly of the same converter valve, a second feedback signal with different phases is obtained.

9. The feedback signal detection system for the converter valve module according to claim 6, characterized in that, The voltage detection module generates two feedback signals based on the voltage at the module terminal. One feedback signal is directly output through the first optical transmitter port as the first feedback signal. The other feedback signal is first transmitted to the logic module. When the logic module receives the feedback signal from the voltage detection module, it immediately outputs a delayed feedback signal as the second feedback signal through the second optical transmitter port after detecting the rising edge of the signal from the timing module.

10. The feedback signal detection system for the converter valve module according to claim 9, characterized in that, The valve control device is also used to simultaneously trigger different high-potential plates in the valve assembly of the same converter valve to generate a first feedback signal, and simultaneously trigger the delayed output of the second feedback signal to start timing, so as to realize that different high-potential plates in the valve assembly of the same converter valve perform corresponding delayed outputs.

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