An implementation of a smart maximum power point tracking controller to harvest renewable energy of wireless sensor nodes

In wireless sensor network (WSN) application one of the main requirement is the self-powered of the nodes. This is why it is increasing the use of renewable source (i.e. photovoltaic (PV)) for supplying power to WSN node. A Maximum Power Point Tracker (MPPT) controller circuit is required to be implemented in order to guarantee the maximum power efficiency of the system. Therefore, in the scenario of renewable energy harvesting, the consumption as well as the tracking performance of the MPPT controller represents a crucial point. The paper proposes a low power implementation of MPPT controller for WSN application. The proposed implementation scheme guarantees the maximum power point tracking performance requiring just 330 μW of power consumption. An ultracapacitor as storage device has been used. The proposed scheme has been implemented and tested for a wireless pressure sensor node under typical both solar irradiance conditions.