Contents I. Introduction
In recent days the growth of industries and modernization of domestic life creates more electric power demand. To balance the power demand the countries are moving to new generation units that are the penetration of renewable energy sources or increase the capacity of the existing plants. While increasing the plant complexity, maintaining the power quality is too difficult, during the sudden loading condition. In order to handle this situation, selecting of best controller and interconnection of power plants with renewable energy sources are necessary to improve the quality of power system operation and control. The term power quality includes voltage, current, and frequency deviations in the power grid. During the abnormal condition, these parameters have deviated from the nominal limit; this is a not good one for the electrical equipment at the consumer end. In this research work, the deviation in the frequency is taken as the problem and finds the proper solution to maintain the frequency at standard at all loading conditions. To control and maintain the frequency deviation, each power plant has a primary controller. Those controllers are not enough to properly function the system effectively.
