Enhancement of power quality using UPQC integrated with renewable energy sources through an improved sparrow search-based PID controller

Conventional energy sources such as thermal power plants provide a significant amount of energy to the power system. However, these sources produce pollutants that contribute to environmental pollution. This problem can be mitigated by integrating renewable energy sources (RES) such as solar and wind power plants into the existing electrical infrastructure, helping to develop a pollution-free grid. However, integrating RES into the power grid causes various power quality (PQ) issues such as voltage sag, voltage swell, harmonics, and unbalanced voltages. Several methods have been examined in the literature to address PQ issues in power systems, including RES. The major issue is the PQ problems in grid-connected RES. The proposed study investigates the PQ issues arising from the source side of grid-connected RES. The sparrow search algorithm (SSA) optimization is used in the proportional-integral (PI) controller to efficiently control the switching pulses of the dynamic voltage restorer (DVR), thereby addressing PQ issues in an integrated solar-wind energy power grid. The integration of a DVR, connected in series with the unified power quality conditioner (UPQC), efficiently addresses PQ challenges such as voltage sag, swell, harmonics, and unbalanced voltages from the generator side of the power grid and its integration with solar and wind energy sources. This approach shows improved results compared to previous research and other optimization techniques. The performance of the proposed system has been investigated using the SimPower Systems toolbox of MATLAB Simulink version 2023b on an Intel i7 core processor, and the results demonstrate that the proposed technique efficiently resolves PQ issues in an integrated power grid system.