Cascaded PD-PI controller for active power frequency control of two-area multi-units power system

In interconnected multi-area power system; the real power generation within each area has to be managed through active power frequency control considering scheduled power exchange. In this work, two different controllers, namely cascaded PD-PI and conventional PID controller are considered for analyzing the dynamic response of the two area interconnected power system. Area-I consists of two reheat type thermal generating power plant units and area-2 comprises of two non-reheat type thermal power plant units. The controller gains of PD-PI and PID controllers are efficiently tuned by 'Teaching Learning based Optimization Technique'. In area-I, 1% step load disturbance is applied for analyzing the dynamic performance of the proposed controllers. It is being observed that the cascaded PD-PI controller performs better than the other one in many aspects.