Resarch On The Intelligent Control Technology Of AC Contactor Electromagnetic System

The traditional AC contactor has some defect,such as noise impact, low life expectancy, loss of serious shortcomings and so on, it has been unable to meet the current requirements of social development and energy, and they can not be used in high-voltage environment, so improving the performance of AC contactor is imminent. When using AC power to magnetize the coil,the contacts of contactor might be bounce when the current become zero.When the conducts pulls in, the flux of the electromagnetic, the speed of contacts, coil voltage and current and other parameters are quite different. And the action have large dispersion, difficult to control. The electromagnetic agency material wear and tear, divided magnetic is easy to break; therefore, the intelligent control tend to run with DC operation.In this paper, the process of closing and opening AC-contactor solenoid system were intelligent improvemented,which takes CJ20-10A as study and takes dsPIC30 as control core. It can start the process to achieve a closed loop coil current chopper control, change the real-time duty cycle signal and the current size, so it can make contact with the moving core with good suction reaction force, and can achieve real-time, fast process control. The breakthrough of maintained low pressure in the closed after stabilization, which reduces power consumption. Contactor breaking process has taken negative control, which can effectively improve the breaking speed. This paper describes the current limit on/off switch control and the TVS opening control, and by PROTEUS software for electromagnetic control module pull breaking process simulation, which verified the feasibility of digital intelligent control. Finally, taking CJ20-10A AC contactor as the control subjects were related experiments.In addition to the innovation transformation of the AC contactor closing and opening stages,the system is also adding reliable and practical intelligent protection and acquisition functions, including AC contactor overvoltage, undervoltage, overload, leakage protection and other functions, thus ensuring in the process of opening and closing operation, AC contactor works stability.