PWM Schemes with Two Switching Frequencies to Reduce THD

The integration of renewable energy resources presents a significant set of technical and infrastructure challenges to power grid operation and control. Besides, it has been proven that it is less harmful to the environment. Power electronics technology has the capability to mitigate the effects of the issues imposed on the power system by the rapid expansion of renewable energy development and increased penetration level at the utility scale. Although power electronics technology is considered a promising potential solution, power conversion efficiency in the rectifiers and inverters must be improved to optimize system performance. A novel pulse width modulation technique is presented to improve the conversion efficiency. This method has two major concepts. First, widening the on-state of the converter's operation will increase the output fundamental component. Inverse sinusoidal pulse width modulation is one of the methods that can achieve this concept. Second, the rate of change in the information at the peak of the sinusoidal reference is relatively small. The modulation of this period has less significance in comparison to the rest of the reference cycle.