期刊名称：International Journal of Distributed Sensor Networks
印刷版ISSN：1550-1329
电子版ISSN：1550-1477
出版年度：2013
卷号：2013
DOI：10.1155/2013/627963
出版社：Hindawi Publishing Corporation
摘要：Recently, photovoltaic-supercapacitor-based energy
systems have become more and more popular in the design
of energy harvesting wireless sensor networks (EH-WSNs) as
an alternative to battery power. Existing research on this area
mainly focuses on hardware design and the improvement of the
charging efficiency. However, energy is wasted not only by the inefficient charging process, but also the inefficient discharging process and energy leakage. Therefore, to maximize node lifetime and
energy utilization, all the previous energy loss should be considered.
In this paper, we develop realistic hardware models of
the complete photovoltaic-supercapacitor energy systems and
propose the efficiency-aware, a systematic duty cycling framework
to maximize energy utilization. We formalize the maximization
problem as a nonlinear optimization problem and develop two
efficient algorithms for its optimal solutions. The performance of
our approaches is evaluated via extensive numeric simulations,
and the results show that our efficiency-aware framework can,
respectively, achieve 60% and 56% more active time (i.e. energy
utilization) than the fixed duty cycle scheme and leakage-aware,
a state-of-the-art scheme for photovoltaic-supercapacitor energy
systems.
