JUL/AUG 2019 35
ow would you like it if your EV could go ten
percent farther with the same size battery?
You’d love it, of course, and so would every
EV manufacturer out there. Range is one of
the most important parameters in the EV industry, as
many potential EV drivers are apprehensive about lower
range ratings.
Manufacturers can always add more battery capacity
to increase range, but that adds weight and, more im-
portantly, increases cost. A better solution would involve
fixing inefficiencies in the EV powertrain, which would
result in more bang for your battery buck.
Bruce Renouard, CEO of power electronics start-up
Pre-Switch, can attest to that. His company has devel-
oped a method to dramatically improve the efficiency
of power converters, a crucial element in the EV pow-
ertrain. Power converters usually lose a lot of energy as
heat - Pre-Switch cites an estimate that 20 percent of
the planet’s electrical power is wasted in power convert-
ers. Though power converters are used in all sorts of
electronics and electrical equipment, EVs are positioned
to be one of the biggest beneficiaries of Pre-Switch’s
technology.
H
“The EV guys, they’ve got a big problem,” said Ren-
ouard. “They’ve got this big, heavy battery they’ve got to
carry around. Anything that makes that system more
efficient is paramount to them.”The switching problem
Power converters take in one form of electricity and
convert it from AC to DC or vice versa, change the volt-
age or frequency, or some combination of these. When
the change is from DC to AC, as is needed between an
EV’s battery and its motor, the converter is called an
inverter.Soft-switching uses an
auxiliary circuit to control
the timing of the switches
in such a way as to
eliminate power losses.