CURRENT
SENSORS
28
P
By Jeffrey Jenkins
IN EVS
A CLOSER
LOOK AT
retty much every electronic circuit that
handles significant power utilizes some
means of measuring current, whether to
simply protect against overload or because
it is a basic functional requirement. In this article we’ll
cover some of the more common devices and circuit
techniques for measuring current in the major subsys-
tems of an EV, including when to choose one over the
others.
Current can be sensed or measured in one of two
ways, really: via the voltage drop across a resistor of
some sort, otherwise known as a shunt, or via the
intensity of the magnetic field which radiates from any
current-carrying conductor. In the former case, the
shunt can be an actual resistor made expressly for the
THE TECH