一种新型双频控制大功率逆变器的仿真研究

Simulative Research on a Novel High Power Inverter Based on Dual Frequency Control Technology

该文介绍了一种新型双频控制高压大功率逆变器,其拓扑由一个可以采用GTO等低频开关器件的大功率逆变器单元(主逆变器)和一个可以采用IGBT等高频开关器件的小功率逆变器单元(辅逆变器)级联组合而成。主逆变器单元采用定脉宽控制方式,主要用于输出功率以提高整个逆变器的功率等级;而辅逆变器单元采用多电平PWM控制技术,主要用于提高波形质量和改善系统动态响应性能。为避免主逆变器和辅逆变器之间由于输出极性相反时出现电流倒灌现象,该文提出了一种新的控制策略并进行了仿真验证。文中以五电平二极管箝位式逆变器作为逆变器单元进行了详细分析,仿真结果表明,这种双频控制逆变器具有输出电压等级高、输出电压谐波含量小、开关损耗低、控制简单等优点。

A new kind of high voltage and power inverter based on dual frequency control technology is introduced in this paper. With the cscade topology , which consists of higher voltage unit （ master inverter ） with slower switching devices such as GTO and lower voltage inverter unit /slave inverter） with faster switching devices like IGBT, this type of convener can he used for medium-high voltage application. The master inverter is mainly used for incresing power output with setting pulse width control technique, while the slave one is mainly used for improving dynamic response and the output waveform with multilevel PWM method. A novel control strategy is presented to prevent reverse current between master inverter and slave inverter when the output voltage of the inverter unit is the opposite polarity. Simulation validation is carried out. A diode-clamp five-level converter using as the inverter unit is discussed in detail. From the simulation results, the novel converter has many advantages, such as high level output voltage, low output distortion, low switching loss and simple control.