Fig. 9From: A new two-degree of freedom combined PID controller for automatic generation control of a wind integrated interconnected power systemImprovement in responses with the combined controller during simultaneous changes of load (as shown in Fig. 10), wind disturbances. (+ 3% at 20 s and − 6% at 40 s). a Area I frequency change; b area II frequency change; c tie line power changeBack to article page