Research on Position Detection Method of Intelligent Contactor Based on Closed-Loop Motion Process

The arc and collision of contactor during the breaking and closing of AC contactor are the main factors of influencing its electric life, the closed-loop servo control is the effective way to achieve its closing with low speed and non-bounce and opening with fast breaking and non-arc by changing the excitation current to make it running according the planned speed, so real-timely and accurately detecting its speed is the key factor to realize its closed-loop control. Aiming at the problem of now available speed detection device with low measurement accuracy,small range and complex structure so that it can′t get a well application for contactor, in this paper presenting a new method of speed detection and a device, Analyzing the key factors which affecting the accuracy of speed is the magnetic flux. Calculating the influencing of magnetic pressure and flux leakage to flux calculation with two methods of magnetic circuit modeling and finite element calculation, the magnetic induction density keeping constant can greatly improve the accuracy of detection through the linear gap compensation. Simulation and experimental results show that the method has advantages of high precision and fast response, and can well meet the speed detection for AC contactor.