预制舱式变电站负荷支路漏电监测方法设计

Design of Leakage Monitoring Methodfor Load Branch Circuits of Prefabricated Cabin Substations

为了确保预制舱式变电站运行的安全性与平稳性,需要监测负荷支路的漏电情况。为此,设计一种针对预制舱式变电站的负荷支路漏电监测方法。首先,对预制舱式变电站负荷支路的漏电等效电路进行分析,并以此为依据开展预制舱式变电站负荷支路漏电暂态电流信号分析,从而选出可完成判断的电流信号。然后,设计电流信号采集方案,引入经验模态分解方法消除电流信号中存在的噪声,以提高电流信号的质量。最后,根据采集的电流信号,建立四种不同电流信号负荷支路漏电判据,以实现预制舱式变电站负荷支路漏电监测。试验结果表明,该方法的信号去噪效果较好,可将信噪比数值提高到85 dB左右,对支路漏电情况的监测精度较高。该方法可有效提升变电站负荷支路漏电监测效率。

To ensure the safety and smoothness of the operation of prefabricated cabin substations, it is necessary to monitor the leakage of load branch circuits.To this end, a leakage monitoring method is designed for load branch circuits of prefabricated cabin substations.Firstly, the leakage equivalent circuit of load branch circuit of prefabricated cabin substation is analyzed, based on which the transient current signal analysis of leakage of load branch circuit of prefabricated cabin substation is carried out, and the current signal that can complete the judgment is selected.Then, the current signal acquisition scheme is designed, the empirical modal decomposition method is introduced to eliminate the noise in the current signal and improve the quality of the current signal.Finally, according to the collected current signal, four different current signal load branch circuits leakage criterions are established to realize the prefabricated cabin substation load branch circuits leakage monitoring.The experimental results show that the signal denoising effect of the method is better, which can improve the signal-to-noise ratio value to about 85 dB , and the monitoring accuracy of the branch circuit leakage situation is higher. The method can effectively enhance the efficiency of substation load branch circuits leakage monitoring.