| Electric power steering(EPS) is a newly-developed power steering system in the recent years. EPS uses motor as power source and microprocessor as control unit; it can adopt different intelligent control and achieve the best steering result. EPS can meet all demands of steering performances and has overwhelming advantages on operation, safety and environmental protection comparing with traditional hydraulic power steering system. This dissertation does some embedded investigation focused on the high performance EPS system which is based on brushless motor.This paper includes research of EPS control principle, detailed analyses of implementation methods and theory of EPS control strategy, and finally realize the steering function by using the mothod of motor armature current. This paper also includes research of core control skills of BLDC in EPS, deep discussions of connections of phase current and generatrix current, made a low-cost, high precision brushless DC motor phase current testing programme, combined with engineering practice and given the phase current and generatrix current sampling methods; Discussed the principle of BLDC damping control, and gives practical application; On a new PWM control strategy to reduce the power consumption of the system, improve the reliability of the system.Based on the theory, the EPS designed in this paper takes XC2365 of infineon company as its core control technology and adopts TLE7183 to build drive circuit. The software had developed a strongly-structured program for EPS which can achieve precise control of torque under different situations. System architecture and the design of hardware and software are presented in detail in the text,and the hardware structure and program block are given.At the last of this paper, tests had been done based on this and the result showed that: the BLDC of EPS designed in this paper have good performance. It had laid a soild foundation for further research...
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