Unified MPPT Control Strategy for Z-Source Inverter Based Photovoltaic Power Conversion Systems

作者：Thangaprakash Sengodan^*

来源：Journal of Power Electronics, 2012, 12(1): 172-180.

DOI：10.6113/JPE.2012.12.1.172

• Capacitor voltage control
• Maximum power point tracking
• Photovoltaic array
• Pulse width modulation
• Z-source inverter

Z-source inverters (ZSI) are used to realize both DC voltage boost and DC-AC inversion in single stage with a reduced number of power switching devices. A traditional MPPT control algorithm provides a shoot-through interval which should be inserted in the switching waveforms of the inverter to output the maximum power to the Z-network. At this instant, the voltage across the Z-source capacitor is equal to the output voltage of a PV array at the maximum power point (MPP). The control of the Z-source capacitor voltage beyond the MPP voltage of a PV array is not facilitated in traditional MPPT algorithms. This paper presents a unified MPPT control algorithm to simultaneously achieve MPPT as well as Z-source capacitor voltage control. Development and implementation of the proposed algorithm and a comparison with traditional results are discussed. The effectiveness of the proposed unified MPPT control strategy is implemented in Matlab/Simulink software and verified by experimental results.

• 出版日期2012-1