A comparative study between PI,PD,PID and lead-lag controllers for power system stabilizer

Stability of power system is an important factor in electric system operation. In this paper, power system stabilizer(PSS) based on four controllers were implemented on a single machine infinite bus system for attaining stability. Four controllers used were PI,PD,PID and lead-lag. Then a comparison study was done with the above controllers. These results were simulated in MATLAB. Each controller has its own advantages and disadvantages. The comparative study was done for speed deviations, load angle deviations and terminal voltage deviations. Then the lead-lag controller was tuned using Particle Swarm Optimization method and was optimized.

I. Introduction

Electricity which is an increasing demand leads to the persistent demand to operation of the power system. So power system stability and the quality power to the consumers have equal importance that as the electric power demands. The size and structural components of electric power system vary even though they have some basic characteristics. For the generation of electricity synchronous machines are used. Prime movers convert the primary source of energy to mechanical energy which in turn converts to electrical energy by synchronous generators. Electric power generated at generating stations, through a complex network of individual components are transmitted to consumers. The individual components includes transmission lines, transformers and switching devices. With a high degree of efficiency and reliability form of electrical energy can be transported and controlled. A wide variety of disturbances occurs frequently and electric system must withstand and remain intact for these disturbances.