互相关技术在钳口法接地电阻检测中的应用  

Application of Mutual Correlation Analysis in Clamped Grounding Resistance Testing

作　　者：余为清[1] 

机构地区：[1]华东交通大学载运工具与装备省部共建教育部重点实验室,江西南昌330013

出　　处：《华东交通大学学报》2013年第3期96-100,共5页Journal of East China Jiaotong University

摘　　要：论述了钳口法接地电阻检测的工作原理。通过对信号互相关的分析,重点对带有噪声的微弱感应电流信号的提取方法进行了分析。给出了以AD630锁相器为核心的信号处理模块,利用DDFS芯片ML2035信号作为参考信号,实现了对接地回路感生电流信号的锁相放大,通过实验标定的方式,确定出接地电阻计算的系数,该方法能够有效地抑制噪声,提高接地电阻的测量精度,简化了信号提取电路,同时由于输出信号为直流,降低了信号采样的难度。This paper discusses the clamped grounding resistance testing principle based on the signal correlation analysis,focusing on how to extract the weak induced current signal with noise. With reference to the ML2035 signals,the signal processing module with the AD630 lock-in amplifier as the core is established, which realizes lock-in amplification of the ground loop induced current signal,reduces the noise effectively and determines the grounding resistance calculation coefficient by experiments. The results show the circuit structure is simplified and the signal can be got easily since the output signal is DC.

关 键 词：接地电阻 互相关 锁相放大 AD630 

分 类 号：TM934.15[电气工程—电力电子与电力传动]