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Department of Electrical Engineering
and Electrophysics
The Department of Electrical Engineer-
ing and Electrophysics of the Institute of
Thermomechanics AS CR, v. v. i. is en-
gaged in the analysis and modeling of
electric drives and rotating machines
along with the experimental verification
of the achieved results. The most impor-
tant methods for the conversion of me-
chanical energy into electrical energy and
vice versa are analyzed. Research is also
focused on current problems connected
with the circuit structures of power elec-
tronic converters and algorithms of the
digital control and diagnostics of these
converters. The mutual effects of power
electronic converters with both the ma-
chines that are supplied from them and
the supply networks to which they are
connected are analyzed.
Considerable attention has been paid to
systems with multi-phase machines in re-
cent years. The use of such machines can
lead to improving the energy efficiency
and the reliability of electric drives. The
goal of increasing the reliability of varia-
ble-speed drives is to propose measures
for keeping the drive in operation even
if some of its components fail. A related
area of research is the compensation of
unbalanced three-phase power supplies
of semiconductor converters that can, in
practice, result in the significant deterio-
ration of the operating characteristics of
electric drives.
Advanced control algorithms of AC drives
are developed and tested experimental-
ly with prospective utilization in industry
and traction. A power supply from mul-
tilevel frequency converters is developed
for these drives. Studies focus on the un-
favorable high-frequency phenomena
(EMI) due to operation of the converters.
Models of the individual components of
the drives, also valid for high frequencies,
are proposed and experimentally verified.
As far as the electromagnetic compatibil-
ity (EMC) in electric power engineering
and the quality of electrical energy are
concerned, algorithms are developed to
control the active power filters with the
goal being to compensate for higher har-
monics, unbalanced loads, power factor
and flicker, and to control energy flows in
transmission, distribution, and industrial
networks.
The Department has at its disposal sever-
al laboratories for measurement on elec-
tric machines and drives up to the output
of 160 kW. The laboratories are equipped
with several dynamometers, a number
of high-quality measuring devices and
modular control systems as well as with
equipment for EMC measurements.
Institute of Thermomechanics AS CR, v.v.i.
Dynamometer with rated power of 160 kW in Laboratory of Power Electronics
Modeling of magnetic field distribution in electric
machine
