Power quality optimization framework for three phase microgrids with grid tied solar PV and battery storage under...

Area of Science:

• Electrical Engineering
• Power Systems
• Renewable Energy Integration

Background:

• Non-linear loads and converter-dominated systems degrade power quality in renewable-integrated microgrids.
• Existing solutions often lack dynamic adaptation to varying load and source conditions.
• Maintaining Total Harmonic Distortion (THD) below IEEE 519-2014 standards is critical for grid stability.

Purpose of the Study:

• To develop and evaluate a coordinated source-filter control framework for microgrids.
• To optimize power quality by selecting the best source-filter combination hourly.
• To ensure THD compliance with minimal active filtering intervention.

Main Methods:

• Modeling of a 100 kW grid-tied solar PV array, 60 kWh Battery Energy Storage System (BESS), and utility grid.
• Implementation of Shunt Active Power Filter (SAPF) and hybrid (SAPF + passive LC) filters.
• Hourly optimization using a Genetic Algorithm to select the lowest THD source and apply filtering only when necessary.

Main Results:

• The BESS + SAPF configuration maintained sub-5% THD under heavy non-linear loads.
• Solar PV systems required SAPF with load-current referencing for moderate distortion levels.
• The utility grid needed hybrid filtering to reduce THD from over 24% to below 3% under significant non-linear loading (≥50%).

Conclusions:

• The proposed optimization framework successfully ensures hourly THD compliance in microgrids.
• The approach enhances microgrid power quality and supports reliable renewable energy integration.
• This work contributes to achieving UN Sustainable Development Goal 7 (Affordable and Clean Energy).