Accuracy analysis of the zero-order hold model for digital pulsewidth modulation

This paper examines the accuracy of the zero-order hold (ZOH) model of the digital pulsewidth modulator (DPWM). The influence of the computational delay on the precision of this equivalent DPWM model is discussed in detail. A compensation method is proposed to compensate the deviation of this DPWM model for accurately calculating the stability region with different computational delay and duty-cycle update modes. Simulation and experimental tests are executed to verify the correctness of theoretical analysis.