Research On Stability Control Of Diesel Generator Sets On Parallel Operation

The ship is tend to be large scale,all kinds of load power of the ship are also increasing,the original single capacity has been unable to meet the needs of the development of modern ship,at the same time intelligent ship has become an inevitable trend of the ship,so the control of the ship power system puts forward higher requirements.Now parallel diesel generators operation mode is widely used in ship power station,the problem of power allocation between parallel units is an important part of the stable operation of the ship power station.When the generator set in parallel,always occur power oscillation phenomena,cause great hidden trouble to the safe operation of power system,even to paralyze the power system.The traditional control method of parallel unit usually adopts PID control,due to the ship power system controlled object mathematical model of diesel generating set has not decided,then introduce the intelligent control method with adaptive ability.This thesis adopts the single neuron PID control method,research of ship power system stability.Firstly,this thesis introduce the traditional PID control method,describes its working principle,followed by single neuron control theory which is expounded in detail,considering the merits and demerits of the two control methods,designed the single neuron PID controller.Single neuron PID control parameters can be adjusted in real time,have the self learning,the adaptive ability,at the same time have the simple structure and easy calculation characteristics of PID control,this method combines the advantages of both,with high precision,strong adaptability,good robustness properties.Based on the analysis of the diesel engine speed regulation system and generator excitation system,derivate the respective mathematical model,and the controller was designed using the single neuron PID control method.Under the environment of MATLAB simulation,the simulation experiments are made on suddenly increasing and suddenly decreasing 100% load.Compared traditional PID control with single neuron PID control on the effect of the two methods on the system response.The experimental results show that the single neuron PID control in the aspect of improving system dynamic accuracy is superior to traditional PID control.In this thesis,on the basis of the existing model,firstly make comprehensive control of voltage and current of diesel generator set,suddenly increase and suddenly decrease 100% load,analyze diesel engine speed and voltage of the generator dynamic characteristic curve.After introducing parallel coupling relationship between voltage and current unit,to establish the mathematical model of parallel unit,the two sets parallel system are simulated.The simulation results show that using single neuron PID control method to design controller,through effective control of diesel generator speed and the stability of the synchronous generator voltage,to ensure the load power evenly distributed between the two sets.The simulation results show that,using single neuron PID control can have better deal with the stability of the nonlinear and time-varying system providing fundamental basis for multimachine parallel system.