Medium Voltage Power Electronics Converters and Methods:
Increased efficiency and reliability with reduced footprint
Overview
Lead Inventor
Hamid A. Toliyat, PhD
Electrical & Computer
Engineering
Research Interests
 Power converters for
electric machines
including multilevels
 Fault tolerant control &
detection
 Magnetic gears &
machines
 Fractional Slot
Concentrated Winding
(FSCW)
Conversion of one form of electric power to
another is frequently required in various
applications. This conversion often requires
an approach with multiple stages, large
electrolytic capacitors, and bulky isolation
transformers. Multiple power electronic
converter topologies (ac-ac, ac-dc, dc-ac, and
dc-dc) were developed with a single-stage
power conversion system to offer galvanic
isolation and soft switching in order to
provide greater efficiency and reliability in a
much smaller than conventional form-factor.
Technology
These soft-switching topologies exploit the concept of stacking switch modules so that
the converter terminals can accept a high or medium voltage level. The power converters
incorporate a high frequency transformer to provide galvanic isolation, the incorporation
of a high frequency transformer v. a low frequency transformer reducing space and
weight, thereby enabling the converter to be smaller.
Benefits




Reduced voltage stress  Use of faster switching devices
High frequency transformer  smaller, lighter converters
No electrolytic capacitor  higher reliability and longevity and smaller size
Zero-voltage switching (ZVS)  lower dv/dt and EMI, higher efficiency, simpler
cooling measures
 Current shaping at input and output terminals  Lower distortions and THD
Applications
 Photovoltaic grid-connected/stand-alone converters, battery chargers, LED lighting
systems, light-to-light systems, switch-mode power supplies and UPS, motor and
generator drives, interface between ac systems with equal or unequal voltage ratings,
HVDC
Stage of Development
Contact
Xiaomin Yang, PhD, MBA
Senior Licensing Manager
Texas A&M University
Technology Commercialization
(979)-845-0907
XiaominYang@tamu.edu
Docket: 4320
 Theoretical concept and simulations testing
 Design and test of various disclosed topologies
Patent Status
Patent Pending
Publications
H. Toliyat, et al, “Ultra-sparse AC-link converters.” IEEE Transactions on Industry Application, 51.1,
2015.
H. Toliyat, et al, “Sparse AC-link buck-booster inverter.” IEEE Transactions on Power Electronics,
29.8, 2014.
H. Toliyat, M. Amirabadi, “Sparse parallel partial resonant AC-link converter.” IEEE Applied Power
Electronics Conference & Exposition (APEC), 17-21/03/2013.