移相全桥零电压开关pwm设计实现设计说明

移相全桥零电压开关 PWM 设计实现摘 要移相全桥电路具有结构简单、易于恒频控制和高频化,通过变压器的漏感和功率开关器件的寄生电容构成谐振电路,使开关器件的应力减小、开关损耗减小等优点,被广泛应用于功率场合。近年来随着微处理器技术的进展，各种微控制器和数字信号处理器性能价格比的不断提高，采纳数字控制已经成为大中功率开关电源的进展趋势。相对于用实现的模拟控制，数字控制有许多的优点。本文的设计采纳 TI 公司的高速数字信号处理器TMS320F28027 系列的 DSP 作为控制器。该模块通过采样移相全桥零电压 DC-DC 变换器的输出电压、输入电压与输出电流，通过实时计算得出移相 PWM 信号，然后经过驱动电路驱动移相全桥零电压 DC-DC 变换器的四个开关管来达到控制目的。实验表明这种控制策略是可行的，且控制模块可以很好的实现提出的控制策略。关键词：移相全桥；零电压；DSPPhase-shifted Full-bridgeZero-voltage SwitchingPWMDesign and ImplementationABSTRACTPhase-shifted full-bridge circuithastheadvantagesofsimple structure,easy toconstant frequencycontroland high-frequencyresonant circuitconstitutedbytheleakage inductanceofthetransformerandthe parasitic capacitanceofthepower switching devices, toreducethestressoftheswitching devices, switchingloss is reduced,which widely used in high-poweroccasion. In recent years, with thedevelopment of microprocessor technology, a variety of microcontrollers and digitalsignalprocessorcost performancecontinues to improve, the use of digital controlhas becomethe development trendofthelargeandmedium-sized powerswitching power supply. Relative toachieveanalogcontrol, digitalcontrolhas many advantages.The design usesDSP ,the TI company TMS320F28027 series of high-speed digital signal processor, as the controller. The module through the samplingphase-shiftedfull-bridgezero-voltageDC-DC converteroutput voltage, inputvoltage and outputcurrent, obtainedthrough real-timecalculation ofphase-shiftedPWM signalphase-shiftedfull-bridgezero-voltageDC-DCconversion, and then afterthedrive circuitth...