A novel whole-line quick-action protection principle for HVDC transmission lines using one-end voltage

摘要

A novel rapid protection principle for HVDC transmission lines only using voltage signal from one-end is proposed in this paper in order to solve the problems of traditional protection principle using one-end data of HVDC, such as poor reliability and insufficient sensitivity. By analyzing the transmission characteristic of the electric network, which is made of reactor and DC-filter of HVDC transmission systems, it is clear that when internal and external fault occurs, the measured voltage is obviously different for some special frequency-band signals. For the difference, internal and external fault can be distinguished. Compared with the traditional protection methods, the protection principle is simple and has absolute selective and a general setting principle, the sample frequency is lower, and it is easy to be implemented. It can substitute the traveling-wave-based method for primary protection with more practicability in project. Simulation results show that the proposed protection principle can identify the fault occurring in the DC line or beyond the DC line and it can identify the fault pole. Moreover, it can operate rapidly, reliably, with high sensitivity and selectivity, under different fault conditions.