Dual PWM Control for High Step-Up DC-DC Converters

A dual PWM control scheme is presented to design the high step-up DC-DC converter. Both high frequency and low-frequency PWM waveform generators are utilized to synthesize the required dual PWM control. This resulting PWM waveform will lead to various switching cycles. Five operation modes will be defined accordingly. The basic operational principle of the proposed converter and the corresponding small-signal switched model are studied in details. The high step-up conversion ratio can be achieved as the duty cycle of the high-frequency PWM is exactly equal to that of the low-frequency PWM through exploring the voltsec balance condition. Simulation studies and hardware prototype implementations are conducted to validate the proposed design with satisfactory performance.