On-line monitoring technology for MOA on HV transmission line

Metal oxide arresters (MOAs) are widely used on HV transmission lines for over-voltage protection. However, it is still difficult to carry out its on-line monitoring, because of some bottlenecks such as the installation of sensor, signal transmission and on-site power supply, et al. This paper first discusses the improved acquisition sensor for getting leakage current value and recording the number of arrester discharge operations. It is convenient for microprocessors obtaining data from the acquisition sensor. Then the paper presents the on-line monitoring system. It contains an advanced RISC machine (ARM) processor responsible for acquisition and algorithm of harmonic analysis. The high performance processor finishes complex calculation on field in order to reduce large amounts of data transmission. The general packet radio service (GPRS) communication technology is applied so that remote signal transmission is accomplished by wireless network. Solar energy battery is employed to obtain continuous power. This apparatus has low power consumption and high performance. It provides a good platform for deeply research on monitoring and diagnosing of MOA.