Photovoltaic maximum power point tracking without current sensor for module integrated converter

Abstract

In this paper, a simple maximum power point tracking (MPPT) method for series-connected DC-DC converter module of photovoltaic power conditioning systems (PCS) is proposed. This approach enables maximum power point (MPP) tracking control with the converter's output voltage information instead of calculating solar array power, which significantly simplifies the sensor network by removing current sensor. Furthermore, there is no multiplication process in the P&O algorithm to track the maximum power point because the power calculation is replaced by output voltage sensing. This simple MPPT control strategy can reduce the cost and size, and can be utilized with a low performance / low cost controller. For verification of the proposed control strategy, Zigbee (Xbee-pro) wireless communications and DSP's Series Communications Interface are utilized. Also series-connected hardware prototype with multiple photovoltaic modules was built and tested.