Abstract: In order to improve the cross regulation of dual-output DC-DC forward converter,and enhance the output voltage accuracy and dynamic performance of the power supply in the application environment that the output loads will change,a main and auxiliary synchronous control strategy is proposed.Calculate out the two output powers and make a comparison between them,and then on the basis of rules set in advance to determine which the main circuit is,and also the other is the auxiliary circuit corresponding.The main circuit adopts closed-loop PID control,and auxiliary circuit uses the improved hysteresis current control strategy,both of them adjust the duty cycle of the switch tube simultaneously.Make a simulation on the work process of the forward converter adopting the proposed strategy in MATLAB/Simulink and complete the hardware circuit,the simulation and experimental results show that both the main and auxiliary circuits have high output voltage precision when one load changes.It improves the cross regulation problem,and also verifies the design is feasible.

Key words: Dual-output, Forward converter, Main and auxiliary synchronous, Cross regulation