Power Quality Improvement in Smart Grids Using a Five-Level Mmc and Ddsrf

Abstract

This paper introduces a novel method for fixing smart grid power quality problems by employing a Modular Multilevel Converter (MMC) with five stages. The reference currents in the proposed converter are generated from the AC source using the Decoupled Double Synchronous Reference Frame (DDSRF) theory, resulting in sinusoidal harmonics that are antiphase to the load current. To extract or inject reactive power at the Point of Common Coupling (PCC), a Unified Power Flow Controller (UPFC) is used. Utilizing the DDSRF theory, a hysteresis controller is implemented to produce Pulse Width Modulation (PWM) pulses for the shunt and series compensators. To further ensure stability and control, the DC Link voltage across capacitors is managed using the Proportional-Integral-Derivative (PID) method. The proposed method is realized in MATLAB through the use of a PID controller and simulated under different loading conditions. The purpose of this paper is to look into the effects of harmonics, in particular, on power quality when the MMC is connected to the load. Insights into the proposed solution efficacy in reducing power quality issues and increasing grid stability in smart grid environments are provided by the simulation results. The research highlights the importance of using real-world parameters, with a focus on the rated parameters rather than the default values. The analysis is simple and straightforward because it does not use optimization techniques to enhance smart grid power quality.