Research On Electromagnetic Design Simulation And Experiment Of High Power DC Contactor

The rapid development of new energy vehicles has put forward more requirements for direct current(DC)contactor.Currently,since new energy vehicles require endurance mileage and reliability,the DC contactor is moving toward high voltage and current.Therefore,the research of high power DC contactor has theoretical and practical significance for improving the reliability and safety of new energy vehicles.The dissertation analyzes and calculates the contact displacement and the over-travel based on 600A/750V DC contactor,the spring anti-force and electromagnetic force are determined,and the structure size and coil parameters of the contactor model are calculated.The static and dynamic characteristics of the simulation model are analyzed by the finite element method.The influence of the spring coefficient,the size of the coil and the height of the structure on the dynamic characteristics of the contactor are analyzed and compared to obtain the optimal combination of contactor with the orthogonal test method.A universal and reliable control system is designed to reduce the energy consumption.Based on the framework of the control system,the central process unit module,the power module,the sampling module and the low voltage protection module are designed and analyzed by using the modular design concept.The software includes the main program and the sub-program which consists of data processing,current protection and liquid crystal display.Finally,a prototype of DC contactor and the hardware circuit are manufactured,the experiment platform is built,and the software system is tested.The performance parameters of the DC contactor,such as the making time and the peak current,are measured and compared with the simulation results.The experimental results verify the reasonability of the structural design and the feasibility of energy saving control.