A Controller Based on Electric-Charger Balance Theory for Front-End Converters

摘要

Aiming at the problem that between the second harmonic current i_(2nd) and dynamic response characteristic of the middle bus voltage u_b of the two stage inverter, the charge balancing controller integrated with the traditional double-loop controller is proposed. The traditional controller operates as load stable to suppress the secondary harmonic current i_(2nd), but the load switched by the new controller. Based on the traditional double-loop controller, the design of the voltage-loop controller that meeting requirements of i_(2nd) is expounded, containing the influence of cross frequency ω_c on △u_b and the final dynamic response time t_s of u_b. The working principle of the electric-charge-balancing controller and some other key design issue are described. A prototype of 450 W is built to verify the correctness of the theoretical analysis and the feasibility of the new converter.