Research On Parameters Tuning Of PID Controller And Its Application On Inverter Control

Since the PID controller came now, the development of control theory experiencedclassical control theory、modern control theory and intelligent control theory. PIDcontroller is used widely in industrial process control for its simple structure、reliablework、good robustness、easy to implement and be effective in engineering.First this paper describes the commonly used parameters tuning methods of PIDcontroller. Usually normalizing method and trial and error method were used for tuningPI controller parameters, which is difficult to obtain the optimal tuning parameters, thispaper presents a fast and effective PI controller parameters tuning method based onfour-dimensional date visualization algorithm. Bode plot graphics cluster is reflected inthe four-dimensional visualization of the amplitude-frequency characteristic diagramand phase-frequency characteristic diagram by use of visualization method, it candirectly observe the relationship between kp, kiand the amplitude-frequencycharacteristic and phase-frequency characteristic. This method may be indirectlyamplitude margin and phase margin performance in the frequency domaincharacteristics, by observing the changes in frequency domain characteristics to achievethe purpose of tuning. Simulation examples show that the method is suitable forlow-level or high-level accused of objects to get satisfactory results, the step response toverify the correctness of the method.Further the works of the single-phase SPWM inverter were analyzed, and themathematic model of it has been built, based on it, the state equation and the transferfunction were deduced out. Draw the system of configuration diagram, and simulate themodel structure of the system. Simulation results show that the waveform distortion islarger and THD value is higher. So the voltage and current feedback were injected, thevisualization algorithm is applied to the design of the single-phase inverter, the PIcontrol strategy was used to carry out to control the output voltage. Simulation resultsshow that the output voltage and current waveform of single-phase SPWM inverter isbetter and more stable whose static and dynamic performances are finer, and THD valueis lower based on the PI and Double-loop control.Then analysis both steady and transient state of single-phase diode bridgerectifier, and deduce mathematical model based on the results. The summary and perspective of the paper are given in the end.