Maximum power point tracking without current sensor for photovoltaic module integrated converter using Zigbee wireless network

• Output voltage of photovoltaic converter in output-series has monotonic relationship with power.
• MPPT control without current sensor is done using the output voltage information instead of power.
• Proposed method is successfully verified through theoretical analysis and hardware experiment.

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