基于串联电容器冷工作状态试验的检测与探讨

Detection Based on Series Capacitor Cold Duty Test

目前用于串联补偿设备的电容器在运行过程中故障率较高,现有对串联电容器常规试验的标准中只采用直流电压做耐压试验,而没有符合实际工况的交流耐压试验。笔者根据IEC关于串联电容器的标准中冷工作状态试验这一型式试验,与实际工况相结合,对以工频为基础的串联电容器过负荷常规试验进行改进。首先通过MATLAB仿真软件确定试验回路的可行方案。随后建立了符合IEC冷工况波形参数的试验平台,并对实际试品进行试验与结果分析,发现了试品电容量随试验次数无规律小幅变化的现象。最后,根据试验分析结果,提出了将IEC型式试验改进为串联电容器耐受过负荷能力常规试验的若干建议。

In the existing standard, DC voltage is only employed for routine voltage-withstand tests of series capacitor. However, AC voltage-withstand test conforms to the actual working conditions. In this study, according to the cold duty test in the IEC type test standard for series capacitors, actual working conditions were considered to modify the routine overload test of series capacitors at power frequency. Firstly, the software MATLAB was adopted to design a feasible scheme of the test circuit. Subsequently, a test platform in accordance with the waveform parameters of IEC cold duty test was established, and tests on real samples were conducted, and the results showed that the capacitance varies with the number of test irregularly. Finally, some suggestions were offered about substituting the routine series capacitor short-circuit overload capability test for the IEC type test.