IEEE Electrification Magazine - March 2016 - 44

Table 1.
The results of the ISG system architecture trade study.
HV
Power

LV
Power

(kW)

Dual windings, start with LV winding, threshold power

Dual windings, start with LV winding, objective power

Normalized

Total

Size

Weight

Efficiency

Score

1.00

0.84

1.00

0.95

0.96

0.72

0.99

0.89

Dual windings, conventional starter, threshold power

0.93

0.85

1.00

0.93

Single HV winding + dc-dc and conventional starter

0.80

0.73

0.97

0.77

Single LV winding + dc-dc

0.83

0.34

0.95

0.37

Single HV winding + dual alternators and conventional starter

0.71

1.00

0.90

0.33

board, provided some amount of heat-sinking capability. An extension of this work has also been done, reducing the size of the converter significantly with the use
of a higher frequency of 27.12 MHz. Currently, the prototype converter with air-core inductors works well when
the hottest point reaches about 250 °C. In the future,
with the use of SiC devices, the ambient operating temperature is expected to be 300 °C.

Heat Sink

LMR

LF
CMR

LS
CS
CP

MOSFET

Autotransformer

(a)
Drain Voltage

500

Measured

400

Simulated

Voltage (V)

300
200
100
0

-100

100
150
Time (ns)

200

250

200

250

Anode Voltage

100

Measured

50
Voltage (V)

Simulated

0
-50

-100
-150
-200
-250

100
150
Time (ns)
(b)

Figure 13. The prototype dc-dc converter with all printed circuit board magnetic components: (a) the converter and (b) the drain and anode voltages.

I E E E E l e c t r i f i cati o n M agaz ine / March 2016

Summary and conclusions
This article outlined the various activities undertaken
within the U.S. Army RDECOM-TARDEC GVPM on the
technical areas related to power electronics and electric drives. The intent was to provide an overall idea of
the activities and also some details on specifications
and requirements relevant to military applications. In
the military, there are various applications that call for
much higher power than is necessary in regular commercial vehicles, and the environment of the application can be very harsh in terms of temperature and
vibration. Some of the important differences between
military and regular commercial applications were
noted. To meet the army's needs, both robust and highefficiency devices are important. Since the military is
seriously considering the electrification of many types
of equipment and vehicles, this article described a few
areas, which, hopefully, the reader will find beneficial.
There are additional activities pertaining to power
electronics and electric drives that have started recently or have not yet been completed, and those are not
included here. This article is intended to provide a general overview of the important technologies that are
highly relevant for power and mobility related to military applications, and it underlines the importance of
power electronics and electric drives in terms of the
modernization of existing systems.

acknowledgments
The support received from the U.S. Army RDECOM-TARDEC and GVPM upper-level leadership is very much

Table of Contents for the Digital Edition of IEEE Electrification Magazine - March 2016