Abstract：A novel dynamic-reference-current (DRC) control strategy is proposed to improve the conversion efficiency and transient response of buck converter operating in pesudo continuous conduction mode (PCCM). Herein, the dynamic reference current for inductor freewheeling is obtained by the weighted average of the load current and the sensed inductor current. Compared with the conventional constant-reference-current controlled PCCM buck converter, DRC controlled PCCM buck converter improves the conversion efficiency and output voltage ripple under light load by load current feedback, and also improves the transient response by introducing the inductor current and load current. Theoretical analysis is verified by simulation and experimental results.
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2017, Vol. 32 
