Development and design of a power supply system for intelligent monitoring equipment in smart grids
Keywords:
Smart grids, Electromagnetic induction, Tapoff power, Intelligent monitoring equipment.Abstract
In recent years, a variety of distributed intelligent moni
toring equipment has been installed in smart grids, and this
equipment often requires low-power DC supply. This paper
examines a power supply system which is used by distributed
intelligent monitoring equipment in smart grids. The power
supply system taps-off low-power from the transmission line
or bus bar through the Faraday electromagnetic induction
principle. First, the induction coil through which the transmis
sion line or bus bar pass obtains low AC power, then AC volt
age is rectified and filtered to a DC voltage which is converted
into 5V by a DC/DC converter. A lithium battery (LB) was
used as a standby power module to solve the dead zone of the
induction coil. Finally, a power management module based on
the STC15F2K60S single chip was able to switch between the
energy of the induction coil and standby module by monitor
ing battery voltage and output voltage, so that output voltage
and current can supply the intelligent monitoring equipment.
Experiments indicated that this power supply system could
stably supply 5W power in 5V when the current of the trans
mission line or the bus bar is in the range of 0~1000A.