Research On PI Parameter Self-tuning And Fuzzy PI Controller Of DC-DC Converter

In recent years,DC-DC converter has extensively application in power electronics and power transmission,communications and other fields.In addition,PID parameter tuning and the theory of controller have a more thorough development.Here a series of simulation has been studied based on the existing theoretical basis,combining with the professional research of the DC-DC converter.This article uses Matlab 2012 a as simulation software,with the feature of the DC-DC converter and treating the theoretical research of the PID parameter tuning and the Fuzzy Control as basis.Simulation experiments of different chopping circuits are carried out.Then conclusions are drawn below:Firstly,the PID parameters of DC-DC converters are self-tuned based on relay feedback control.The Buck-Boost circuit is mainly studied in this paper,and the output voltage of the circuit is served as a feedback.In the Simulink of Matlab,parameters self-tuning is simulated.The relay feedback method is more convenient to calculate the PID parameters(mainly PI parameters)and for a certain point of self-tuning.The simulation results show that auto-tuning based on relay feedback is more convenient,and the effect is better.Secondly,since the object transfer function obtained by the relay feedback method is related to the operating point,it is tested near the operating point.Then improve the circuit design and get a more ideal waveform.Thirdly,the fuzzy adaptive control is introduced to the controller based on the static operating point auto-tuning.When the working parameters of the chopper circuit(such as input and output voltage and component parameters)change,the PID controller parameters can be corrected in real time.The simulation results show that the effect of superimposed adaptive control is better than that of fixed parameter PID control.