We have had serious problems due to the over current flowing in 3 phase electrical power systems. In order to solve these problems, various kinds of circuit breakers have been developed. But those circuit breakers have such faults as relatively slow s...
We have had serious problems due to the over current flowing in 3 phase electrical power systems. In order to solve these problems, various kinds of circuit breakers have been developed. But those circuit breakers have such faults as relatively slow switching operation and low sensitivity to the variation of load current. Moreover, they have very complicated circuit, and cost very much.
The circuit developed in this paper has a high reliability, a very short switching time and a high sensitivity as a result of the adoptation of electric-potentio method to detect over current. It is also very simple, so the expense of it is very cheap.