Voltage controller with energy management unit for microgrid with hybrid sources

Abstract

An unprecedented year has past with Covid-19 lockdown. It has underscored the importance of reliable and uninterrupted power supply. Microgrid ensures reliability and continuity of power supply in a local region with its own local generation and load despatch system, thereby reducing or eliminating the need of a central generator. A microgrid is capable of autonomous operation or it can be connected to a central ac grid that it separates from during disturbances. In this paper results of a microgrid simulation model is presented. Here microgrid system uses two renewable sources namely, solar PV and wind generator along with a battery feeding an inverter supplying load. The system is modeled and implemented using Matlab/simulink environment. The simulation model consists of mono-crystalline solar PV panel of 2.5 kW and a wind turbine emulator having PMDC as wind generator of 1 kW rating as micro sources. For stabilisation of the system a battery bank of 48 V, 100 Ah is also provided. The system is designed to supply a maximum load of 2.5 kW. The system autonomy is approximately two hours for rated load of 2.5 kW. Stability of the system was tested during load variations. The voltage and frequency were found to be stable during load variations. The performance of the inverter to provide constant output voltage of 400 V is good and the output frequency of the inverter is also maintained at 50 Hz. The output voltage conforms to IEC 60038 Standards. An energy management scheme is also developed and simulation results show effectiveness of the scheme.