基于自整定Fuzzy-PI控制的电流跟踪型光伏并网逆变器

CURRENT TRACKING PV INVERTER BASED ON SELF-TUNING FUZZY-PI CONTROL

介绍了一种单极性并网逆变器,相对于双极性并网逆变器具有损耗低、谐波小、电磁干扰小的优势,更适用于并网逆变控制。首先对DC/DC变换器进行建模,随后提出一种将模糊自整定控制理论融合PID控制规律之中的自整定Fuzzy-PI控制策略,将太阳电池板产生的直流电逆变为220V/50Hz的正弦交流电提供给电网,最后建立了基于Fuzzy自整定PI控制的电流跟踪型光伏并网逆变器完整的Matlab仿真模型。仿真结果表明,基于该方法生成的PWM控制信号较之传统PID控制等可有效减小跟踪误差,并迅速跟踪目标并网电流波形,从而提高系统的动态响应性能。

An unipolar grid-connected inverter was presented, which possesses the advantage such as low loss, small harmonics, small electromagnetic interference etc. comparing with bipolar inverter, more suitable for on-grid inverter control. Firstly, the DC/DC converter was modeled, then self-tuning Fuzzy-PI control strategy was put forward, which integrating fuzzy self-tuning control theory with PID control law , the direct current produced by solar panels was inverted into the sinusoidal AC 220V/50Hz to provide to the grid. Finally, Matlab simulation model for current tracking PV inverter was completed based on the Fuzzy self-tuning PI control. The results show that the generated PWM control signal based on the method can effectively reduce the tracking error of traditional PID control and quickly track the target and net current waveform to improve the system＇ s dynamic response.