Automotive Engineering - April 2021 - 32

Pumping
EV heat

ELECTRIFICATION FEATURE

Van Batenburg explains electrifiedvehicle technology to an ACDC
class in Europe.

If there was ever a poor choice of descriptors, calling something that
gets hot a " chiller " would be it (8). This component cools the PE (7;
power electronics) but its purpose in the HVAC system is to warm the
refrigerant on its way back to the compressor. That makes it easier
for the compressor to do its job. Less effort equals less energy from
the high-voltage battery and more range. A lot more range? No, but
every little bit helps. The PE coolant had not been used on the Nissan
Leaf before, so now we are recycling energy (a Kia idea) we otherwise would lose as waste heat. Clever, those engineers, applying
Reduce, Reuse and Recycle to transportation.

Condenser icing
When the heat pump is on and the climate outside the vehicle is wet
and above freezing (33-deg. F to 45-deg. F; 1-deg. C to 7-deg. C), the
exterior of the condenser (5) may freeze as the air moving through it
lowers the air pressure and the temperature drops. If the condenser
has iced up, the heat-pump system stops working. What now? The
HVAC computer will turn the A/C back on; this will now melt the ice
as the condenser gets hot. Air flaps in the evaporator will move the
cold air from the A/C outside as the high-voltage air grid heater (12)
is turned on to heat the cabin.
At this point the main battery pack (13) will be asked to provide
more energy than when the heat pump was the sole provider of cabin heat. As the outside (ambient) temperature drops below freezing
and/or the air dries out, the front condenser will stop icing up. This is
all done without the driver knowing what is going on.
To stay warm is a human desire. In the beginning of the modern
electric-vehicle age, many early EV adopters had to resort to their
32 April 2021

ACDC's industry training
After 35 years as an automotive
service technician (25 years
owning his own repair shop),
Craig Van Batenburg bought a
Honda Insight in 1999. That same
year he founded ACDC in
Worcester, Massachusetts, as a
vehicle-emissions training comCraig Van Batenburg
pany. In 2004, he closed both
businesses and transformed
them into HEV training, adding EVs when they arrived.
In the early years, ACDC customers were mainly independent repair-shop owners and technicians. That audience now
includes factory techs and engineers from vehicle OEMs and
suppliers, including Honda R&D, Honda Manufacturing of
America, John Deere R&D, Midtronics, Delphi, Autoliv and
others. Van Batenburg describes his training style as " downto-earth, knowledgeable and dynamic. "
During the 2020 COVID lockdown, he and the ACDC staff
compiled a college-level book on electrified-vehicle technology, including fuel cell vehicles, that was recently published.
Van Batenburg is most proud of being a dad and helping
foster kids. To contact ACDC, email: Craig@fixhybrid.com.
Web site: www.FIXEV.com.

cars' heated seats and heated steering wheel - while
wearing a jacket, hat, gloves and heavy socks - to stay
warm while optimizing vehicle range. Opting for cabin
heat or reaching your destination is not a choice that
EV drivers should have to make.
AUTOMOTIVE ENGINEERING

BOTH IMAGES: ACDC

Chiller

http://www.FIXEV.com

Automotive Engineering - April 2021

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