This paper proposes a novel directional pilot protection method based on the transient energy for bipolar HVDC line.Supposing the positive direction of current is from DC bus to the DC line,in the case of an internal ...This paper proposes a novel directional pilot protection method based on the transient energy for bipolar HVDC line.Supposing the positive direction of current is from DC bus to the DC line,in the case of an internal line fault,the transient energies detected on both sides of the line are all negative within a short time,which denotes the positive direction fault;while for an external fault,the transient energy on one end is positive,which means a negative direction fault,but the transient energy on the opposite end is negative,which indicates that the fault direction is positive.According to these characteristics,an integration criterion identifying fault direction is constructed.In addition,through setting a fixed energy threshold,the faulted line and lightning disturbance can also be discriminated.Simulation results from UHVDC transmission system show the validity of the proposed protection method.展开更多
The multi-terminal VSC-HVDC grid is believed to be widely applied in the future power system. The dc line protection is the key technique for operation security and power supply reliability of the dc grid. In this pap...The multi-terminal VSC-HVDC grid is believed to be widely applied in the future power system. The dc line protection is the key technique for operation security and power supply reliability of the dc grid. In this paper, the single-ended protections, namely, the traveling-wave based protection and transient-variable based protection, as well as the pilot protections, mainly including the directional pilot protection and current differential protection, are discussed in detail. With the analyzed protections, the effective main and back-up protection strategy can be configured for the dc line in multi-terminal VSC-HVDC grid.展开更多
基金National Natural Science Foundation of China(51677109)National Key Research and Development Program of China(2016YFB0906003).
文摘This paper proposes a novel directional pilot protection method based on the transient energy for bipolar HVDC line.Supposing the positive direction of current is from DC bus to the DC line,in the case of an internal line fault,the transient energies detected on both sides of the line are all negative within a short time,which denotes the positive direction fault;while for an external fault,the transient energy on one end is positive,which means a negative direction fault,but the transient energy on the opposite end is negative,which indicates that the fault direction is positive.According to these characteristics,an integration criterion identifying fault direction is constructed.In addition,through setting a fixed energy threshold,the faulted line and lightning disturbance can also be discriminated.Simulation results from UHVDC transmission system show the validity of the proposed protection method.
基金supported by the National Natural Science Foundation of China(No.U1866205).
文摘The multi-terminal VSC-HVDC grid is believed to be widely applied in the future power system. The dc line protection is the key technique for operation security and power supply reliability of the dc grid. In this paper, the single-ended protections, namely, the traveling-wave based protection and transient-variable based protection, as well as the pilot protections, mainly including the directional pilot protection and current differential protection, are discussed in detail. With the analyzed protections, the effective main and back-up protection strategy can be configured for the dc line in multi-terminal VSC-HVDC grid.
