GENERATING UNIT MODELING AND CONTROL OF AN ISOLATED DIESEL

Abstract

Both simulation and experimental approaches for modeling a diesel­ generating unit connected to an isolated load are developed. The overall system is represented by a nonlinear mathematical model, which has one delayed input.

This delayed system is transferred into an exact and uniqu alternative system without delayed neither in the state nor in the input .The nonlinear model has a set of seven nonlinear differential equations. These equations are represented by an analog computer for experimental studies.

The performance of the open loop system is studied when subjected to various disturbances caused by load switching. These studies show large deviations in load voltage and frequency, which are not accepted by the consumers.

A 3'd reduced order linear model is derived form the nonlinear model. A comparison between the nonlinear full order model and reduced model results is developed which refelects the accuracy of the linearization and reduction processes.

The reduced order is used in the design process of an optimal controller to regulate the generator output. The performance of the closed loop system is studied when subjected to the same disturbances in the open loop system. These study refelects the accuracy of the optimal controller .The comparison between the optimal controller and the conventional AVR control is developed.