基于振动信号的高压断路器合闸特性参数在线检测方法研究

Study on on-line detection of high voltage circuit breaker closing characteristic parameters based on vibration signal

机械特性参数是评价断路器动作性能的有效依据,传统测试方法不能在线测试,且传感器安装复杂。提出了一种利用振动信号提取断路器合闸过程中运动时间参数的方法。首先根据断路器弹簧操作机构的工作原理,分析了断路器在合闸运动过程中各个部件之间的冲击引发的对应的振动;然后对采集到的存在噪声的干扰振动信号采用变分模态分解对其进行分解,选择与原始信号波形变化相一致的分量进行重构;最后采用基于短时能熵比的双门限法实现了振动信号时域内关键时刻点的时间参数的检测,完成了断路器合闸过程中时间参数的提取。通过振动信号的理论提取的时间参数和传统的动触头行程曲线提取的时间参数进行对比分析,验证了所提方法的正确性。

The mechanical characteristic parameter can be used to evaluate circuit breaker performance. However, traditional methods can't be used for online test, and the installation of sensor is also complicated. To solve this problem, a new method for timing parameters extraction of the vibration signal of a circuit breaker in the closing process is proposed. Firstly, based on the principle of spring operating mechanism, the corresponding vibration caused by components impact in the closing process is analyzed. Then, in order to eliminate the noise in the vibration signal, the variation mode decomposition is adopted to decompose the vibration signal, and the signal is reconstructed by selecting the components whose waveform change is consistent with the original signal. Finally, the double threshold method based on the short-time energy entropy ratio is used to detect the timing parameters of the critical moment in the time domain of the vibration signal, completing the extraction of timing parameters in the circuit breaker closing process. Through the comparison of the timing parameters extracted from the theoretical vibration signal and the experimental travel curve, the correctness of the proposed method is verified. This study provides a new method for on-line detection of high voltage circuit breaker characteristic parameters.