Implementation of On-line Monitoring System for Zinc Oxide Arresters in Substations

• Main Authors: Chun-Hao Lin, 林俊豪
• Other Authors: Cheng-Chien Kuo
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/dfrky3

碩士 === 國立臺灣科技大學 === 電機工程系 === 105 === The study develops a low-cost On-line monitoring system for Zinc-Oxide arresters in order to monitor its present condition. When the arrester ages, the user can know the condition of the arrester and effectively avoid damaging surrounding electrical equipment. The most important is that it improves the safety and stability of the power supply and, at the same time, reduces the cost of the equipment and possibly make the device available locally. The system integrates and analyzes the total leakage current, resistive leakage current, difference of phases. Collecting local researches and foreign researches, including different methods of monitoring arresters, finds out suitable indicators to estimate the present condition of the Zinc-Oxide arrester. The system architecture is divided into three parts: Front-end Measurement Unit, Diagnostic Analysis Unit, and Remote Monitoring Unit. The Front-end Measurement Unit is mainly composed of a Cortex-M3 embedded system, which uses a high-precision current sensor to measure the leakage current of the arrester in order to evaluate the current of the arrester. In addition, an electric field sensor is used to measure the phase voltage of the arrester. The Front-end Measurement Unit transforms the current and voltage to digital data and sent to the Diagnostic Analysis Unit through the network. The Diagnosis Analysis Unit is mainly composed of the Raspberry Pi 2 microcomputer. The graphic user interface in the monitor can provided users a way to operate the device which can analyze condition of the arrester. Then, the Diagnosis Analysis Unit sends the data to the Remote Monitoring Unit through the network. The Remote Monitoring Unit is composed of industrial computers to monitor the real-time situation of multiple arresters through the network in order to systematically manage and increase the possibility of applying the system on substation. The tests prove that the system can effectively show results of ageing of arresters by comparing the system with commercially available arrester detection software.