The research and development of completely-isolated and plug-in breaker of the overhead line

Nowadays, the isolating rate of the overhead lines at 10 kV level is already popular to a certain extent, however there still remain bare in some critical parts of the critical devices. As a result, they bring about frequent short-circuit fault. Directed by the Lean Production concept, and through the collection and analysis of the sample data of faults and failures that have happened these years, we´ve found out that most faults, especially those that caused large scale black out, are line-cable faults, which happen at joint part between overhead line and cable. Based on that fact, a new type of circuit breaker should be developed to improve the isolating rate of lines and to shorten the time of fault classification and fault current interruption. The two functions seem beyond the range of existing device. Finally, we´ve developed a new type of breaker with completely-isolated shell and in the plugged mode. During the course, the operating unit is simplified to meet the demand so that it will not take too much effort to jump the cable. The enclosed equipment is largely improved in the breaker´s efficiency while the completely-isolated shell remarkably lowers the risk of getting hit by an electric shock. Meanwhile, our equipment can quickly transfer the power load, and gives the advantage to extend the large-scale maintenance without outage time, thus improving the reliability of the power system. In a word, the advent of completely-isolated overhead line breaker in the plugged mode can not only enhance the securities of the device in operation and the operator by increasing the isolating rate of overhead line system, but also speed up the fault classification and fault current interruption.