内馈斩波串级调速系统中斩波器主电路的分析和仿真

Analysis and Simulation of Chopper in Internal Feedback Cascade Control System

传统的串级调速系统功率因数比较差的一个重要原因就是通过采用改变逆变器的移相控制角来对电机进行调速,控制角越大,则逆变器从电网吸收的无功功率越多。如果用斩波器来控制直流电压的大小,而将逆变器的控制角设定为允许的最小值不变,则可降低无功功率,提高系统的功率因数。对内馈斩波串级调速系统中斩波器的作用和斩波器主电路的参数选择作了详细介绍,并用MATLAB仿真软件对斩波器主电路进行了仿真。

One of the most important reason of the conventional cascade adjustable speed system in poor power factor is that it control the motor speed by using phase-controlled inverter, the control angle β is bigger, the inverter absorb more reactive power from the grid. If the DC voltage is controlled by the chopper, and the inverter control angle is set to the minimum value, it can reduce the reactive power consumption and improve the system power factor. The effect of internal feedback cascade control system was introduced, the selection of main circuit parameter of the chopper was introduced in detailed, and simulation of the chopper by matlab simulation software.