功率型半实物仿真系统中高频脉波电压的实时采样

Abstract

半实物仿真系统中通常需要对高频PWM脉波电压进行离散采样以实时数字仿真，瞬时采样不再适用，而低通滤波采样会带来采样延时，影响动态响应速度，甚至引起系统不稳定性。本文研究了基于时域均值采样系统的积分复位采样法，分析了采样电压波形及谐波分量，确定了采样频率的优化选择原则。理论分析和仿真结果表明：该采样方法可以实现PWM脉波电压采样，能实时准确的提取其等效分量，通过优选采样频率能抑制采样电压波形畸变、减小谐波，实现无延时采样，验证了该采样方法的有效性和可行性。 In the PHIL system, real-time sampling for PWM wave voltage is the base of real-time digital simulation. Instantaneous sampling was no longer applicable, while low-pass filter sampling would bring sampling delay and caused system instability. A mean time-domain sampling system was presented, and its sampled voltage waveform was analized to optimize selectting the sampling frequency. The theoretical analysis and simulation results showed that: The sampling method could accurately extract the equivalent component of the PWM voltage, and the sampled voltage waveform distortion could be inhibitted by optimizing the sampling frequency. The simulation results verified the effec- tiveness and feasibility of the sampling method.