Dynamic Modeling and Control of a Synchronous Generator in an AC Microgrid Environment

Abstract

A microgrid system model is created to assess transient and steady-state stability during periods of separation from the grid. A secondary control is constructed to dispatch energy sources according to user selected setpoints and participation factors. Two sources—an energy storage device and a synchronous generator—are controlled to share active and reactive load burdens. A system load models the difference between solar and wind-powered generation and load. First-order differential equations are written to describe the system, and implemented in Simulink. The model components carry a high level of detail to capture all relevant modes. Systems include an eight-state salient pole synchronous machine, an AC8B regulator, a prime mover, an equivalent $\pi$ cable, an RL microgrid load, an ideal battery, a simple inverter model, and a detailed LCL filter at the inverter output. A detailed model of the inverter primary control is included, and a secondary level control, which distributes the power error according to user defined participation factors, is proposed.