微机保护装置的抗浪涌骚扰研究

Research on Surge Immunity for Numerical Protection Devices

分析了变电站受到雷击冲击导致其高压母线发生单相接地故障时产生浪涌骚扰的机理以及浪涌骚扰的特性,并定量分析了共模、差模信号的强度、频谱。针对微机保护装置端口定义的特点,提出了抗浪涌骚扰的对策,并结合实例分析了浪涌骚扰对微机保护安全稳定运行的影响及解决方案。分析结果表明,微机保护装置电源端口、通信端口抗浪涌骚扰的能力较差,在产品设计、生产、运行等环节应针对该特点给出较好的解决方案。

The mechanism of occurring surge disturbance due to the single-phase earth fault of high voltage bus caused by lightning stroke on substation and the feature of surge disturbance is analyzed, the intensities of common mode signal and difference mode signal as well as the frequency spectrum of surge disturbance are quantitatively researched. The surge immunity tests for numerical protection devices are presented. According to the definitions and features of ports in numerical protection devices, the countermeasures against surge disturbance are proposed, the influence of surge disturbance on secure and stable operation of numerical protection devices and corresponding solutions are researched by case study. Analysis results show that both power ports and communication ports of numerical protection devices are easily affected by surge disturbance, thus a better solution should be applied in the links of design, production and operation of numerical protection devices.