Modified genetic algorithm approach to design of an optimal PID controller for AC-DC transmission systems

Abstract HVDC transmission systems can overcome some limitations inherent with AC transmission systems such as transmission over long distances and transmission via cables. One aspect of importance is the improvement in stability achieved with AC–DC transmission systems. In this paper, a methodology for the optimal Proportional Integral Derivative (PID) controller design using the Modified Genetic Algorithm (MGA) is proposed to improve the transient stability of AC–DC transmission systems after faults. This study consists of the formulation of the load flow calculation, basic controls on HVDC transmission systems, a mathematical model selection for stability analysis and a supplementary signal control by an optimal PID controller using the MGA. The proposed method is verified using computer simulation. The results show that the application of MGA-PID controller in AC–DC transmission systems will improve the transient stability. The PID controller design using the MGA method is shown to be advantageous when applied for the AC–DC transmission systems.