A novel classical controller for automatic generation control in thermal and hydrothermal systems

This paper presents automatic generation control (AGC) of interconnected two equal area thermal system, two equal area hydrothermal System and five unequal area thermal system. Thermal plants have single reheat turbines with generation rate constraints of 3% per minute. The hydro plant in hydrothermal system has electric governor and has generation rate constraints of 270% per minute for raising generation and 360% per minute for lowering generation. A novel classical controller based on Integral and Double Derivative control is used in AGC and its performance is compared to several other classical controllers such as Integral (I), Proportional-Integral (PI), Integral-Derivative (ID) and Proportional-Integral-Derivative (PID) controllers. Integral squared error (I.S.E) and Bacteria Foraging (BF) techniques are used for optimization. Investigations reveal on comparison that Integral (I), Proportional-Integral (PI), Integral-Derivative (ID) or Proportional-Integral-Derivative (PID) controllers all provide more or less same response where as Integral - Double Derivative (IDD) controller provides much better response. Further, the controller action can be optimally delayed to provide the best dynamic response.