500 kV GIS电压互感器选型分析

Selection analysis of 500 kV GIS voltage transformer

摘要

分析500 kV GIS电磁式电压互感器铁磁谐振产生的机理，谐振发生所需的条件，谐振类型的判定方法和主要应对措施。根据传统500 kV GIS电磁式电压互感器的励磁特性和清原抽水蓄能电站500 kV GIS低磁密电压互感器的励磁特性，以及电站试验、调试、检修等各种工况下电压互感器及其连接短母线、高压电缆、架空线路的回路特性，计算典型工况下独立系统的等效容抗和电磁式电压互感器的励磁电抗。根据PETERSON曲线分析了传统互感器产生谐振的可能性并定量计算分析出了铁磁谐振的类型。在合同执行阶段会同设备制造商对低磁密电压互感器进行研究，计算结果表明，低磁密电压互感器抗饱和能力突出，在可以预计的所有运行工况下，均不会发生铁磁谐振。

Abstract

This article analyzes the mechanism of ferromagnetic resonance in 500 kV GIS electromagnetic voltage transformers, the conditions required for resonance to occur, the determination method of resonance type, and the main countermeasures. Based on the excitation characteristics of traditional 500 kV GIS electromagnetic voltage transformers and the excitation characteristics of 500 kV GIS low magnetic density voltage transformers at Qingyuan Pumped Storage Power Station, as well as the circuit characteristics of voltage transformers and their connecting short busbars, high-voltage cables, and overhead lines under various operating conditions such as power station testing, commissioning, and maintenance, the equivalent capacitive reactance of independent systems and the excitation reactance of electromagnetic voltage transformers under typical operating conditions were calculated. Based on the PETERSON curve, the possibility of resonance generated by traditional transformers was analyzed, and the types of ferromagnetic resonance were quantitatively calculated and analyzed. During the contract execution phase, a study was conducted with the equipment manufacturer on the low magnetic density voltage transformer. The calculation result showed that the low magnetic density voltage transformer has outstanding anti saturation ability and will not experience ferromagnetic resonance under all predictable operating conditions.

关键词

直接接地系统 / 电压互感器 / 铁磁谐振 / 低磁密 / 运行方式

Key words

directly grounded system / voltage transformer / ferromagnetic resonance / low magnetic density / operation mode

Author summay

王建明(1978—), 男, 正高级工程师, 硕士, 主要从事电气一次设计。E-mail: [e-mail]