A Method of Synchronizing with DUT to Improve the Stability and Accuracy of Power Hardware-In-the-Loop Simulator

The power hardware-in-the-loop (PHIL) simulator can test the performance and stability of the developed system by simulating an environment very similar to the actual plant. To obtain accurate test results, the harmonic current input to the PHIL simulator must be removed. Conventional PHIL simulators reduce the effects of harmonic current by using digital filters that are easy to change frequency. However, in this method, when harmonic current is input to the PHIL simulator as a distorted signal due to the aliasing phenomenon during current sampling, current pulsation occurs and affects the accuracy of the simulation results. Therefore, this paper proposed a synchronization algorithm to remove the current pulsation by analyzing current characteristics by aliasing. The proposed synchronization algorithm can synchronize the PWM phase between two time-varying systems using current pulsation in the PHIL simulator. As a result, it is possible to accurately test the device under test by reducing the current pulsation.