CN-115542082-B - Commutation failure detection method, commutation failure detection device, commutation failure detection apparatus, commutation failure detection storage medium, and commutation failure detection program product

CN115542082BCN 115542082 BCN115542082 BCN 115542082BCN-115542082-B

Abstract

The present application relates to a commutation failure detection method, apparatus, device, storage medium, and program product. The method comprises the steps of firstly determining a target phase in a non-commutation state from each phase of a Y bridge of a converter, then detecting whether the Y bridge meets a first commutation success condition, determining a first commutation valve group with a commutation failure from the commutation valves contained in each phase of the Y bridge except the target phase if the first commutation success condition is not met, detecting whether a D bridge of the converter meets a second commutation success condition if the first commutation success condition is met, and finally determining a second commutation valve group with the commutation failure from the commutation valves contained in the D bridge if the D bridge does not meet the second commutation success condition. By adopting the method, the commutation valve with commutation failure can be accurately positioned, and the commutation failure detection is more accurate.

Inventors

DAI SHULONG
LI LIN
HOU YUNCHUAN
LIU BAISHUANG
TENG ZHAOLIN
ZHOU YASHU
XU XUEHAI
XIN LIANG

Assignees

中国南方电网有限责任公司超高压输电公司曲靖局

Dates

Publication Date: 20260505
Application Date: 20220929

Claims (9)

1. A commutation failure detection method, the method comprising: determining a target phase in a non-commutation state from each phase of a Y-bridge of the converter; Detecting whether the Y bridge meets a first commutation success condition; if the first commutation success condition is not met, determining a first commutation valve group with failed commutation from the commutation valves included in all phases except the target phase of the Y bridge; If the first commutation success condition is met, detecting whether a D bridge of the current converter meets a second commutation success condition, and determining a second converter valve group with failed commutation from converter valves contained in the D bridge under the condition that the second commutation success condition is not met; The determining a target phase in a non-commutation state from each phase of a Y-bridge of the converter comprises: Acquiring each phase of current of the Y bridge; determining a phase which is positive in current in each phase and meets a first current judgment condition as the target phase; The detecting whether the Y bridge meets a first commutation success condition comprises: if the difference value between the target phase current and the line current in the Y bridge is smaller than a preset value, and the change rate of one phase current of the other two phase currents is positive and the change rate of the other phase current is negative, determining that the Y bridge meets the first phase change success condition; the first converter valve group for determining the failure of the commutation from the converter valves included in each phase of the Y bridge except the target phase comprises: Determining that the converter valves on the lower bridge arms of the two phases except the target phase in the Y bridge are the first converter valve group with failed converter; the detecting whether the D-bridge of the converter meets a second commutation success condition includes: if the difference value between the target phase current and the line current in the D bridge is smaller than the preset value, and the change rate of one phase current of the other two phases of current is positive and the change rate of the other phase current is negative, determining that the D bridge meets the second commutation success condition; The second converter valve group for determining the commutation failure from the converter valves included in the D-bridge comprises: And determining that the converter valves on the lower bridge arms of the two phases except the target phase in the D bridge are the second converter valve group with failed converter.
2. A method according to claim 1, wherein said determining a target phase in a non-commutation state from the phases of the Y-bridge of the converter comprises: Acquiring each phase of current of the Y bridge; determining a phase which is negative in phase current and meets a first current judgment condition as the target phase; The detecting whether the Y bridge meets a first commutation success condition comprises: if the sum of the target phase current and the line current in the Y bridge is smaller than a preset value, and the change rate of one phase current of the other two phases of current is positive and the change rate of the other phase current is negative, determining that the Y bridge meets the first phase change success condition; the first converter valve group for determining the failure of the commutation from the converter valves included in each phase of the Y bridge except the target phase comprises: determining that the converter valves on the upper bridge arms of the two phases except the target phase in the Y bridge are the first converter valve group with failed converter; the detecting whether the D-bridge of the converter meets a second commutation success condition includes: If the sum of the target phase current and the line current in the D bridge is smaller than the preset value, and the change rate of one phase current of the other two phases of current is positive and the change rate of the other phase current is negative, determining that the D bridge meets the second commutation success condition; The second converter valve group for determining the commutation failure from the converter valves included in the D-bridge comprises: And determining that the converter valves on the upper bridge arms of the two phases except the target phase in the D bridge are the second converter valve group with failed converter.
3. The method according to claim 1, wherein the method further comprises: Acquiring a phase change angle; And determining the delay time before detecting whether the Y bridge meets the first commutation success condition or not and determining the delay time before detecting whether the D bridge of the converter meets the second commutation success condition or not according to the commutation angle.
4. A method according to claim 3, wherein said obtaining a phase change angle comprises: Acquiring line current, a closing angle, a phase line voltage and a phase-changing reactance of a valve side of a converter transformer connected with the converter; and calculating a commutation angle according to the line current, the off angle, the commutation line voltage and the commutation reactance.
5. The method according to claim 1 or 2, wherein the first current determination condition is that a difference between one of the phase currents and the line current is smaller than a preset value, a sum of one of the other two phase currents and the line current is smaller than the preset value, and the other phase current is smaller than the preset value.
6. A commutation failure detection apparatus, the apparatus comprising: A first determining module for determining a target phase in a non-commutation state from each phase of the Y-bridge of the converter; The detection module is used for detecting whether the Y bridge meets a first commutation success condition or not; The second determining module is used for determining a first converter valve group with failed commutation from converter valves included in each phase of the Y bridge except the target phase if the first commutation success condition is not met; The third determining module is used for detecting whether the D bridge of the converter meets a second commutation success condition if the first commutation success condition is met, and determining a second converter valve group with failed commutation from converter valves contained in the D bridge under the condition that the second commutation success condition is not met; The first determining module is specifically configured to obtain each phase current of the Y bridge, determine a phase that is positive in current in each phase current and satisfies a first current judgment condition as the target phase; The detection module is specifically configured to determine that the Y bridge satisfies the first commutation success condition if a difference between a target phase current and a line current in the Y bridge is smaller than a preset value, and a change rate of one phase current of the other two phase currents is positive and a change rate of the other phase current is negative; The second determining module is specifically configured to determine that a converter valve on a lower bridge arm of two phases except the target phase in the Y bridge is the first converter valve group with failed converter; The third determining module is specifically configured to determine that the D-bridge satisfies the second commutation success condition if a difference between a target phase current and the line current in the D-bridge is smaller than the preset value, and a change rate of one phase current of another two-phase current is positive and a change rate of another phase current is negative, and determine that a commutation valve on a lower bridge arm of two phases of the D-bridge except for the target phase is the second commutation valve group with a commutation failure.
7. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any one of claims 1 to 5 when the computer program is executed.
8. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 5.
9. A computer program product comprising a computer program, characterized in that the computer program, when being executed by a processor, implements the steps of the method according to any one of claims 1 to 5.

Description

Commutation failure detection method, commutation failure detection device, commutation failure detection apparatus, commutation failure detection storage medium, and commutation failure detection program product Technical Field The present application relates to the field of power system fault diagnosis technologies, and in particular, to a commutation failure detection method, apparatus, device, storage medium, and program product. Background Because conventional direct current transmission has the advantages of long transmission distance, large transmission capacity, no problem of stable power angle and the like, a large number of transmission projects adopting conventional direct current transmission technology are built successively in recent years in China, but because an inverter station of conventional direct current transmission is easy to cause commutation failure due to factors such as an alternating current system fault and the like, when the direct current transmission system is in commutation failure, how to detect a commutation valve which is in commutation failure in the shortest time and timely take effective measures is important to improve the stability of the direct current system. However, current commutation failure detection methods are not accurate enough. Disclosure of Invention In view of the foregoing, it is desirable to provide a commutation failure detection method, apparatus, device, storage medium, and program product that are capable of detecting an accurate commutation failure. In a first aspect, the present application provides a commutation failure detection method. The method comprises the following steps: the method comprises the steps of determining a target phase in a non-commutation state from each phase of a Y bridge of a converter, detecting whether the Y bridge meets a first commutation success condition, determining a first commutation valve group with failed commutation from the commutation valves contained in each phase of the Y bridge except for the target phase if the first commutation success condition is not met, detecting whether a D bridge of the converter meets a second commutation success condition if the first commutation success condition is met, and determining a second commutation valve group with failed commutation from the commutation valves contained in the D bridge if the second commutation success condition is not met. In one embodiment, determining a target phase in a non-commutation state from each phase of a Y-bridge of the converter includes obtaining each phase current of the Y-bridge, and determining a phase that is positive in each phase current and meets a first current determination condition as the target phase. In one embodiment, detecting whether the Y-bridge satisfies the first commutation success condition includes determining that the Y-bridge satisfies the first commutation success condition if a difference between a target phase current and a line current in the Y-bridge is less than a preset value, and if one phase current change rate of the two phase currents is positive and the other phase current change rate is negative. In one embodiment, determining the first converter valve bank with failed commutation from the converter valves included in each phase of the Y-bridge except the target phase comprises determining the converter valves on the lower bridge arms of the two phases of the Y-bridge except the target phase as the first converter valve bank with failed commutation. In one embodiment, detecting whether the D-bridge of the converter meets the second commutation success condition includes determining that the D-bridge meets the second commutation success condition if a difference between a target phase current and a line current in the D-bridge is smaller than a preset value, and if one phase current change rate of the two phase currents is positive and the other phase current change rate is negative. In one embodiment, determining the second converter valve bank with failed commutation from the converter valves included in the D-bridge includes determining the converter valves on the lower bridge legs of the two phases of the D-bridge except for the target phase as the second converter valve bank with failed commutation. In one embodiment, determining a target phase in a non-commutation state from each phase of a Y-bridge of the converter includes obtaining each phase current of the Y-bridge, and determining a phase of each phase current that is negative and satisfies a first current determination condition as the target phase. In one embodiment, detecting whether the Y-bridge satisfies the first commutation success condition includes determining that the Y-bridge satisfies the first commutation success condition if the sum of the target phase current and the line current in the Y-bridge is less than a preset value, and if one of the two phase currents has a positive current change rate and the other phase current cha