基于改进MPPT算法的微电网电能质量改善作用研究

Research on Improvement of Micro-grid Power Quality Base on the Advanced MPPT Algorithm

基于最大功率跟踪(MPPT)技术的光伏发电系统,其控制器输出功率参考值由MPPT算法实时计算得到。M PPT算法的快速性、准确性和稳定性可直接影响光伏发电系统的输出功率特性及发电质量。为此,结合单级式光伏并网发电系统的控制原理,分析了MPPT算法对光伏发电系统的控制作用;并针对一种常用变步长扰动算法存在的问题,结合光伏电池的数学模型,提出了一种改进的变步长扰动算法。该算法可有效提高跟踪速度和精度,降低功率波动,提高发电质量。最后,仿真分析了改进前后含光伏发电系统的微电网的电能质量,验证了改进MPPT算法对微电网电能质量的改善作用。

The power quality of PV generation is greatly affected by the maximum power point tracking （MPPT） algorithm. Researc- hing an improvement measure of MPPT algorithm, is an effective way to reduce the power quality problems caused by the PV genera- tion system and improve the micro grid power quality. The drawbacks of a commonly used variable step perturbation algorithm and its effects on the power quality of micro-grid are analyzed. According with the drawbacks, an improved variable step perturbation algo- rithm is proposed combining with the mathematical model of PV cells. And the simulation analysis show that through improving the MPPT algorithm can effectively improve the power quality of micro-grid which contains PV generation system.