Load frequency control of a nonlinear two-area power system

In an interconnected power system, all the generators must run at an appropriate capacity to meet the demand in power. Loss of synchronism between the generators and/or too much frequency fluctuations may cause protective equipment to trip. Load frequency control (LFC) is necessary to balance the power generation and the load, by monitoring frequency and power changes between interconnected power systems in tie-lines. In this paper, power systems from previous research works are analysed for stability, and different types of controllers are designed and validated through simulation and compared with a Proportional-Integral-Derivative (PID) - controlled power system. Three types of controllers are considered, namely Fuzzy, Fuzzy-PID and Adaptive Neuro-Fuzzy controllers. The first power system considered is a linear identical non-reheat two-area system. However, a linear system does not model an actual power system completely because of neglected nonlinearities. Hence, two main sources of nonlinearity (generation rate constraint (GRC) and governor dead band (GDB)), which arise due to practical constraints are considered and included in the model of the system.