基于非整周期模式串联谐振变换器控制技术

Control Technology of Series Resonant Converter with Non-periodic Integral Cycle Mode

针对整周期脉冲密度控制串联谐振变换器输出功率效率低、负载输出电流纹波和偏置电流大的问题,详细分析了基于负载电流控制串联谐振变换器的动态模型及内部运行特点,给出了基于非整周期模式控制下负载电流和电压的状态表达式,提出了基于负载电流的非整周期控制串联谐振变换器的方法。通过比较输出负载电压值和输出负载电流与指令电流运算后的误差,控制谐振变换器分别运行在输出功率状态、自由谐振状态和再生状态3种模式。仿真和实验结果表明了该方法的可行性和有效性。

To overcome the disadvantages of integral cycle mode-controlled pulse density modulation series resonant converter, which are lower output power efficiency, bigger output current tipple and offset current, a series resonant converter with non-periodic integral cycle mode is proposed. The internal operational characteristics and dynamic modeling are investigated in detail and the state expressions of non-periodic integral cycle mode-controlled load cur- rent and voltage are given. A series resonant converter based on load current controlled by non-periodic integral cycle mode is presented. The output voltage and load current error are compared to drive the resonant power stage working in three basic operational modes, that is, powering, free resonance and regenerating. The usefulness of the proposed current control technique is verified through the computer simulations and the experiment results.