Secondary frequency regulation of multi-area interconnected hybrid power system with electric vehicle

Abstract

In modern power system, plugged in electric vehicle plays a very vital role in regulation of system frequency as it is a form of battery energy storage system. This paper presents an aggregate model consisting of a three area system embedded with electric vehicle (EV) in all the three control areas along with Dish-Stirling solar thermal system (DSTS) in only Area-1. The thermal systems are provided with single reheat turbine, governor dead band and generation rate constraint of 3% per minute to give a more realistic view to the designed system. Two degree of freedom Proportional-Integral-Derivative (2DOF-PID) controller with filter is applied as secondary controller in all the three control areas. Maiden application of a new nature inspired optimization technique called Wind Driven Optimization technique in load frequency control is made in this paper. A comparison is done between 2DOF-PID and Proportional-Integral-Derivative (PID) controller to verify the effectiveness of the former. Analysis reveals the advantage of including DSTS in the aggregate model which proves the role of renewable energy sources in overcoming the fluctuations in frequency and tie-line power in a power system under both nominal 1% step load perturbation and random load perturbation. An attempt has also been made to show the impact of incorporating EVs under nominal system condition into the system, and it has been observed that the number and magnitude of oscillations are decreased to great extent with its incorporation.