关键词: 可编程逻辑控制器; 自动重合闸; 可靠性; PLC; 应用
Abstract
According to statistics, permanent fault in the system generally less than 10 per cent and the rest were due to failures caused by lightning over-voltage insulator surface flashover, when the winds of short-term touch lines, tree branches fell from the upper wire transient fault. When the system failure, immediate action to protect the power lines or equipment, in a very short time, the point of failure will automatically extinguish the arc, is insulated to resume. At this point automatically reclosing device moves automatically close the circuit breaker and restore normal operation system.
Aiming at the unreliable factors that the traditional electromagnetic ARD device has more actiongrades and adhering of contact, using PLC to realize the auto-reclosure andmaking the design for hardware and soft-ware, the used components is fewer, accident chance ismuch lower. The method overcomes the defects of the traditional electromagnetic ARD control method. So control flexibility is strong and the reliability of power-supply of control system is high. The artica Analyses the defects in traditional relay automatic reclosing, proposes application of PLC in the design automatic relcosing and draws a ladder chart.
Key words: pragramable log ic con troller ( PLC) ; auto-reclosure; reliab ility; application
