Modeling of Photovoltaic Charging System for the Battery Powered Wireless Sensor Networks

Wireless Sensor Networks (WSN) requires energy harvesters to reduce the frequent replacement of the motes on field. This paper presents the modeling and design of a Solar Photovoltaic Charging (SPC) system with Incremental Conductance algorithm and Boost converter. Modeling of the chosen PV module (950 mW) is done and the characteristics are analyzed. The working of the Maximum Power Point Tracker (MPPT) is checked under arbitrarily varying irradiance and temperature conditions. The generated energy is stored in the 4.8 V, 150 mA NiMH battery. In this paper, mathematical modeling of WSN mote as a resistor based on the energy consumption of the mote in the active and sleep state is proposed. Series Charge regulation is used to improve the battery lifetime. The entire SPC system is developed using MATLAB/SIMULINK.