Improved Hopf Oscillator-Based VOC Method for Fast Synchronization of Parallel Inverters in Standalone Microgrid

Abstract

In this work, a set of weakly coupled Deadzone oscillators (DZO), Van der Pol oscillators (VdPO), and Hopf oscillators (HO) are presented to derive the control methods for parallel voltage source inverters (VSIs). Its dynamic equations determine the inverter frequency and amplitude. The process of selecting parameters for HO is difficult because the parameter’s feedback current gain ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> ) and damping coefficient (μ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> ) have a larger range of values. To address these restrictions, the authors presented a prairie dog optimization algorithm (PDOA) as a means of selecting the HO parameters. The goal is to decrease the settling period of the VSI output voltage during starting, while the constraint is peak overshoot. Finally, the suggested optimized HO approach surpasses existing control approaches in terms of initial response time. The simulation and hardware results of the suggested improved HO (IHO) based VOC method are verified and compared with those of the other control methods to see how well the suggested control method works.