一种针对中压三电平IGCT输出滤波器拓扑的死区补偿方法

A Dead-time Compensation Method for Medium Voltage Three-level IGCT Output Filtering Topology

提出一种针对中压三电平集成门极换向晶体管(IGCT)输出滤波拓扑下的精细化死区补偿方法,实现逆变器输出死区效应的实时计算和补偿。由输出滤波器拓扑建立传递函数,进而得到器件侧输出电流随输出电压和负载电流变化的时域解析式。将滤波器阻抗参数代入时域解析式,依据开关变化时刻的器件侧电流初值进行分段处理,计算补偿时间。该方法定量分析了含输出dv/dt滤波器拓扑应用中不同初值电流对滤波器后端电压非线性变化的影响规律,可以更加精细地补偿电流过零点处的死区效应。

A fine dead-time compensation method based on the medium voltage three-level IGCT output filtering topology was proposed to realize the real-time calculation and compensation of the dead-time effect of the inverter output.Based on the topology of the output filter,the transfer function was established,and the timedomain expression of the variation of the device side output current with the output voltage and load current was obtained.The filter impedance parameters were substituted into the time-domain analytical formula,and the compensation time was calculated by piecewise processing according to the initial value of the device side current at the time of switch change.The method take into account the influence of different initial current on the nonlinear variation of the output-end voltage of the filter in the topological application with dv/dt filter,it can compensate the dead-time effect at the zero point of the current more precisely.