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The battery needs charging and discharging repeatedly in producing, so as to be activated. Most traditional charging-discharging device of storage battery using thyristors has many disadvantages. Such as low power factor and high harmonics. A novel battery charging and discharging device base on PWM is researched and developed, which can operate with unit power factor and low harmonics, and feed the discharged energy back to the utility AC line.The main circuit of this paper is three-phase voltage source PWM rectifiers, which is a strong coupling, time-varying nonlinear system, control is more complicated. This paper focuses on the engineering design and implementation. It takes various elements such as feasibility, reliability, cost and production engineering into the comprehensive consideration, including the research of control methods, the implementation of space vector, the design of hardware and software, and the development of prototype.This paper introduces the basal of three-phase voltage source PWM rectifiers. Firstly, the typical topologies and principal of PWM rectifier is analyzed in this paper. The mathematical models of three-phase voltage source PWM rectifier in ABC three-phase stationary and dq two-phase synchronous rotating coordinate system are established. PI and feedforward decoupling two loop control method is presented completely based on dq mathematical model. The external loop is to control the charging-discharging current or to control the charging voltage. The inner loop tails the current index of the external loop to realize unity power factor and sinusoidal current control. Meanwhile, combined with the theory of AC motor vector control, this paper gives the voltage space vector control of three-phase voltage source PWM rectifier and analyzes its realization method in details.Base basal of three-phase voltage source PWM rectifiers, the hardware design, including the design of main circuit, the sampling circuit, the controlled circuit, the driving circuit and the protection circuit. The hardware design is grounded on production. It is very important to reduce the cost of production, and to take convenient production into consideration, while sticking to feasibility, reliability. Software design base on main control chip TMS320F28035, including structure of program, control algorithm, realization of program. The program has many advantages of simple code, precise calculation and swift response. By building Matlab simulation model, the feasibility of control method is verified by simulation results. The prototype of three-phase voltage PWM rectifier is constructed and debugged, experimental results verify the validity and superiority of its control method and engineering design.
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