基于多频脉冲序列控制Buck变换器的研究

摘要

For the large output voltage ripple and narrow output power range caused by the characteristics of bi-frequency modulation technique,a novel voltage mode multi-frequency control technology is discussed. Multi-frequency control realized the output voltage regulation of switching converter with four preset control pulses. Multi-frequency control Buck converter operating in continuous conduction mode(CCM)and discontinuous conduction mode(DCM)is studied,and the key point in this paper is the characteristics of multi-frequency control for Buck converter which is operated in DCM. Finally,the control pulse combination of the Buck converter operating in a steady-state is also analysed,and the ex⁃perimental prototype is built to verify the correctness of the theoretical analysis.%针对开关变换器双频率控制技术存在的输出电压纹波大、输出功率范围窄等缺点，研究电压型多频率脉冲序列控制方法，该方法通过4组预设控制脉冲，实现开关变换器输出电压的调节。对多脉冲序列控制Buck变换器在电感电流连续导电模式CCM（Continuous Conduction Mode）和电感电流断续导电模式DCM（Discontinuous Conduction Mode）下的工作特性进行分析，重点研究了在DCM模式下Buck变换器多频率控制。最后，分析了DCM Buck变换器工作在稳态时脉冲序列的组合方式，并通过实验验证了理论分析的正确性。