双频Buck变换器参数对系统性能的影响

The Relationship Between Parameter with Performance of Buck Converter with Double Frequency

双频Buck变换器中有两组不同开关频率的功率器件,其中一组工作在高频,用于提高动态响应速度和稳态精度;另一组工作在低频,对高频Buck单元中的电流分流,承担输出功率的任务,同时可以降低损耗。双频Buck变换器可以在提高系统性能的同时提高系统效率,适合于大功率场合的应用,其高低频率及参数对系统性能有重要影响。本文对双频Buck变换器中的高低频率、电路参数对系统性能的影响进行了理论分析,确定了参数设计原则。结果表明,双频Buck变换器的稳态和动态性能与单个高频Buck变换器相同。大量的仿真结果和实验证明了理论分析的正确性。

The buck converter with double frequency is composed of two Buck cells cascaded. One Buck cell works in high frequency to enhance the system performance, and the other one works in low frequency to process the output power. The current flowing in the high frequency cell is diverted by the low frequency one. So the high frequency converter can work in higher frequency to improve the steady and dynamic response with high ediciency, which is suitable for high power applications. The high and low frequency, and the circuit paramter has dominated effects in system performace. The effect of different frequency and the circuit parameter to the system performance is proposed in this, paper. The circuit parameter design criteria is given. The detailed simulation results and experimental results verified the correctness of the theoriatical anlysis.