Combined Frequency and Voltage Control of a Deregulated Hydro-Thermal Power System employing FA based Industrial Controller

This technical write-up emphasizes on combined regulation of frequency - voltage in a restructured renewable energy integrated power system under PoolCo and bilateral transactions. A two area coordinated modeling of area load frequency control (ALFC) and automatic voltage regulator (AVR) is carried out in presence of thermal, hydro, systems. Non linearities are incorporated to get a realistic insight with scheduled delay, rate constraint, and dead band. A powerful algorithm namely Firefly Algorithm based Industrial controllers serve the purpose of classical controller as Secondary control in the considered two area power system. Selection of best secondary controller among integral (I), proportional-integral (PI) and proportional-integral - derivative (PID) controller is carried out based on a fair comparison under Pool Co Transaction Scenario. PID controller serves better. Further investigations are carried out with excitation in AVR loop along with step load perturbation at ALFC in both control areas. PID outperforms I and PI in stabilizing the system responses such as frequency deviation, tie-power deviation and voltage deviations.