Analysis and Evaluation of Hybrid Cooperative Frequency Control for Micro Grids in Islanding Mode in Case of Solar Panel Outage and Load Variation

This paper proposes frequency control of micro grids in islanding mode with expected scenarios. Micro grids are able to operate in islanding mode. One of the most important difficulties for micro grid in islanding mode is frequency instability or frequency fluctuation.

For rapid Frequency Control, power balance between generation and consumption should be provided momentary which can be achieved with ESS like batteries. Battery station with power electronics devices interface (BESS) due to having very fast dynamic response well designed can lead to improve frequency stability via absorption or injection of active power. Normally to achieve maximum usage of battery capacity considering available charge, choosing efficient control method is so crucial. Two different scenarios are considered to prove of efficiency of proposes cooperative control method using MATLAB/SIMULINK software. In the first scenario on islanding mode micro grid is studied in case of load variation but in another scenario both solar panel outage and load variation solar occurrence are simulated.

In both scenarios, the proposed control method is simulated by changing the load and solar cell outflow. It was observed that the frequency oscillations were attenuated by a few tens of seconds and at the same time the battery returned to its minimum value after power was applied. It also keeps the voltage deviations within its normal range. By adjusting the control coefficients, this damping process for frequency fluctuations can be improved.

A new cooperative frequency control method is introduced by combination of frequency control strategy and battery energy storage system via diesel generator attendance, the suggested method presents an efficient method during islanding mode operation of micro grid for frequency fluctuation considering minimum requested power of BESS, provide setting of control coefficients causes improvement of damping rate as well.