Active energy management for harvesting enabled wireless sensor networks

In this work, we propose a novel control based scheme for energy management in wireless sensor networks with energy harvesting capability. The problem is viewed as a queue control problem where the objective is to maintain a reference energy level of the energy storage device. A validated nonlinear queueing model is considered and a robust nonlinear controller is considered whose convergence properties are established analytically. The proposed control algorithm incorporates predictions of the energy to be harvested which are generated using the recently proposed Accurate Solar Irradiance Prediction Model (ASIM). The combined control and prediction scheme is evaluated using analysis and simulations. Preliminary simulation results conducted on the NS-3 simulator demonstrate the ability of the scheme to achieve its design objective as the energy level oscillates about values close to the desired level.

I. Introduction

Wireless Sensor Networks (WSNs) constitute a well established paradigm of wireless on demand systems, serving a number of applications such as patient monitoring, weather forecasting, surveillance, military, wild life monitoring and agriculture [1]. The fixed battery design approach, adopted at their early stages of development, poses significant size and lifetime challenges. Recent developments in energy harvesting technologies and their integration in WSNs, can significantly contribute in alleviating these challenges leading to more effective designs [2].