AC Microgrid Control Using PV and Battery in Typhoon HIL

This research investigates the control of AC microgrid using PV and Battery. The different levels of control in microgrid hierarchy level, such as primary and secondary control have been analyzed and implemented in Real-Time Simulation Software “Typhoon HIL”. The primary control is the fastest and requires no communication network. It works in V-f control mode during islanded mode or VQ/PQ control mode under Grid-connected mode. Based on the load requirement and grid availability, a communication-based Power Management System (PMS) algorithm has been proposed under secondary level of control strategy. The proposed PMS code has been implemented in python, inside the HIL SCADA environment, with the help of a macro widget within the typhoon HIL control center. The PMS aims to utilize microgrid sources and prioritize solar and battery by maintaining stable voltage, frequency, and power under a grid-connected and islanded mode of operation. The Proposed PMS also aims to charge and discharge the battery whenever a surplus amount of energy is present during islanded mode through PV within maximum and minimum state of charge (SOC) limits defined with variable $\mathbf{SOC}_{\mathbf{max}}$ and $\mathbf{SOC}_{\mathbf{min}}$, respectively, on a schematic editor. It can set and control supervisory from SCADA Panel within the typhoon HIL control center. A set of power electronics converters and inverters has been used to integrate PV and battery storage into the AC microgrid system. The model consists of PV, battery storage, PV and battery inverter, contactors, and interruptible constant impedance loads. The different modes of microgrid operation by PMS have been simulated using virtual HIL devices under grid-connected and islanded operation modes.