宽范围双输出Buck-Boost变换器设计与分析OA

To solve the problem of a small output voltage range in single-inductor dual-output Buck-Boost converters,a quadratic unit structure is introduced in this paper,which is the voltage gain by Di/(1-Di)times and significantly expand the voltage range.According to the working state of the power supply inductor,the power supply modes of the converter can be divided into four types,i.e.,complete inductor supply mode,incomplete inductor supply mode,dual-branch supply mode and single-branch supply mode.The voltage gain,ripple voltage and critical inductance values between each mode of the four power supply modes are calculated.The converter has four output states,i.e.,Boost,Buck,Boost-Buck and constant-voltage,and the duty cycle conditions in each output state are derived.Finally,experiments were conducted in four power supply modes and four output states of the converter,proving that the theoretical analysis is correct and the performance of the converter is reliable.