Design and implementation of optimized virtual oscillatory controllers for grid-forming inverters

Area of Science:

• Electrical Engineering
• Power Systems
• Control Theory

Background:

• Renewable energy integration into power grids is increasing, driven by advancements in power electronic converters (PECs).
• PECs are crucial for connecting renewable energy sources (RESs) to the main grid.
• Virtual oscillator control (VOC) is a time-domain method for regulating grid-forming inverters, modeling deadzone oscillators for stable AC microgrids.

Purpose of the Study:

• To address the challenge of selecting control parameters in deadzone VOC.
• To evaluate the performance of VOC optimized with various algorithms against traditional controllers.
• To demonstrate the superiority of a novel VOC optimization approach for enhanced microgrid stability and synchronization.

Main Methods:

• Implemented Virtual Oscillator Control (VOC) for grid-forming inverters.
• Optimized VOC parameters using Particle Swarm Optimization (PSO), Sine Cosine Algorithm (SCA), modified SCA (mSCA), African Vulture Optimization Algorithm (AVOA), and Artificial Jellyfish Search Optimization (AJSO).
• Validated system performance using MATLAB simulations and real-time digital simulation (Opal RT-OP5142), comparing VOC-AJSO with droop, VSM, and conventional VOC.

Main Results:

• The proposed VOC-AJSO demonstrated significantly faster synchronization compared to droop, VSM, conventional VOC, and other optimized VOC methods.
• Optimization techniques like PSO, SCA, mSCA, andAVOA were compared, with VOC-AJSO showing superior performance.
• Hardware results confirmed the effectiveness and faster synchronization capabilities of the VOC-AJSO control strategy.

Conclusions:

• The Artificial Jellyfish Search Optimization (AJSO) effectively optimizes Virtual Oscillator Control (VOC) parameters for grid-forming inverters.
• VOC-AJSO offers a superior solution for achieving rapid synchronization in AC microgrids compared to existing methods.
• The study validates the practical applicability and enhanced performance of the proposed VOC-AJSO control approach through hardware implementation.