【摘要】 Buck型变流器的功率级小信号传递函数会随输入电压变化而变化,对于宽输入电压范围的应用,会出现稳定性和动态不能兼顾的问题。详细分析了Buck型变流器小信号特性,总结了通常的设计方法,并且提出了采用输入电压作为补偿量去影响PWM锯齿波斜率的方案,从而抵消功率级中输入电压的影响。给出了一次侧控制和二次侧控制时具体的输入电压补偿电路。采用补偿电路的Buck型变流器在不同输入电压下环路增益的博德图一致性非常好,变换器能够取得较好的稳定性和动态。该方案解决了宽输入电压范围Buck型变流器的小信号设计问题,使得Buck型变流器更加适合于系统集成。更多还原

【Abstract】 Buck type converters are widely used,however the power stage transfer function will be changed with the change of input voltage.The stability and dynamic performance are hardly designed to a perfect result simultaneously in wide input voltage range applications.Small signal characteristic of Buck converter is analyzed in detailed,and design considerations are introduced.Input voltage is applied as a compensation signal to change the slope of the sawtooth wave and the effect of input voltage in the power stage is eliminated.The concrete compensation circuits are presented for primary side control application and secondary side control application.The Buck type converter with compensation circuit owns the accordant bode plots of the loop gain and performs the good stability and dynamic under wide range input voltages.This method solves the small signal design issue for Buck type converters under wide range input voltages,and makes Buck type converter more suitable for system integration applications.更多还原