Application of DVR Fuzzy PID Control Based on Three-Phase Grid-Connected Photovoltaic System
The photovoltaic (PV) power generation system,vulnerable to the external influence,would generate the voltage fluctuation and harmonic and can not be controlled only by the conventional PID and the fuzzy controller due to its time-varying,nonlinear,multivariable characteristics,resulting in the contradiction problems between the tracking and disturbance rejection requirement,steady and dynamic performance,and the control performance and the robustness.In this paper,the dynamic voltage restorer (DVR) is used to eliminate the problem of the voltage sag,fluctuation,flicker,and the three-phase unbalance voltage of the PV array.Based on conventional PID control,the error and variation rate between the instruction value of the controlled object and the actual value are employed as input.Fuzzy reasoning is used for PID's three parameters Kp,Ki,Kd online self-tuning,in order to meet the requirements for the controller varying with the error and variation rate between the instruction value and feedback value.Finally,the simulation proves the system ideal control effects:faster dynamic response,smaller steady-state error,and better dynamic and static performance of the controlled object.
grid-connected photovoltaic systemvoltage sagdynamic voltage restorer (DVR)fuzzy PID
NETL
NSTL
万方数据
维普
