PWM控制器中阻容耦合导致的非线性分析

Analysis of the Nonlinearity Caused by Resistive and Capacitive Coupling in PWM Controllers

为研究受阻容耦合影响后PWM控制器传输特性的非线性,通过定量的理论分析,得到三角波信号激励下阻容耦合的时域响应,并由具体数据仿真实验得出耦合参数对PWM控制器传输特性的影响。通过仿真和实验发现,时间常数偏小时,响应存在超前、衰减和斜率变化3个特征。其中衰减特征影响PWM控制器传输特性的灵敏度和控制范围,即输出幅度衰减,PWM控制器的灵敏度上升、控制范围变窄;斜率变化特征导致PWM控制器传输特性的非线性,即波形的上升段斜率会由大变小、下降段斜率绝对值由大变小。

To study the nonlinearity of the transmission characteristics of the PWM controller effectted by the capacitance coupling,the time domain response of the PC coupling under the triangular wave signal driving was obtained by quantitative theoretical analysis.Besides,the influence of coupling parameters on the transmission characteristics of the PWM controller was obtained from the simulation of the specific data.The simulation and experiment show that the time constant is small,and there exist three different responses.The attenuation characteristics affect the sensitivity and control range of the transmission characteristics of the PWM controller,whereas the slope change characteristics lead to the nonlinear trasmission characteristic of the PWM controller.