IEEE Electrification Magazine - December 2017 - 23

the control laws for operation over the
entire performance range. This range
spans low-speed, high-torque operation as well as high-speed, high-power
operation, including phase advance
and transient operation.
The motor was also tested at the
wheel actuator level, as well as on
the aircraft. Figure 16 shows the TM
integrated on the landing gear.

PAS Demonstration

During the show,
the airplane
demonstrated the
capability of making
turns, reversing
motion, and cruising
at 10 kn.

Honeywell and Safran conducted the
first public demonstration of the
eTaxi technology during the 50th International PAS held at
Le Bourget Airport, Paris, France, 17-23 June 2013. Later,
more airplane, systems, and components development
testing was performed.
For the PAS, the prototype of the EDS was installed on
the eTaxi A320 demo airplane. There were two EDSs on
the aircraft: one on each main landing gear assembly. During the show, the airplane demonstrated the capability of
making turns, reversing motion, and cruising at 10 kn. The
airplane performed one or two runs (of 5-7-min durations)
every day, including during several rainy days. On one of
the days, the demonstration took place during a very
severe rainstorm without any deficiencies. The eTaxi is
capable of driving the aircraft at maximum takeoff weight
at speeds up to 20 kn. The highest speed for the PAS was
limited to 10 kn due to the PAS's safety regulations. Further development testing took place at the Toulouse Airport, with speeds up to 20 kn.
The eTaxi can bring immediate benefits for a pilot
operating in congested airports. The pilot who drove the
eTaxi in the show commented, "The system is very
smooth and easy to operate, enabling the plane to accelerate without any delay and move at a steady rate. This
is especially valuable in busy airports where planes
are often queuing up for an extended period of time
before takeoff."
Figures 17 and 18 show the TM assembly on the landing
gear and the demonstration airplane, respectively.

Figure 16. The TM integrated on the wheel actuator and the landing gear.

Conclusions

This article summarizes the extensive
analytical work, design, fabrication, and
testing of an EDS used in the eTaxi
demonstrated during the 2013 PAS. The
predicted performance via various
tools has been verified by extensive
testing on both the system and the
component levels. Also, the very successful demonstration verifies that the
adopted architectural approach and the
requirements of all of the components
are properly defined. More specific conclusions are as follows:
xx
Two identical EDS channels have been used, one for
each of the landing gears. Each channel contains its
own ATRU, WACU, and TM. For a future performance
improvement, both the ATRUs can be replaced by one
with a two-times greater power rating. An optimization routine on an EDS level needs to be performed to
obtain a proper allocation of various components to
satisfy power quality and EMI requirements. An optimization routine also needs to be performed for the
overall optimized systems efficiency, as well as for a
powerful provision is the flux weakening. All system
optimizations should be performed in light of a typical operating envelope.
xx
The ac-to-dc converter needs to have voltage boosting
capability to reduce the currents in the WACU, the TM,
and the interface cables, which will lead to substantial
weight savings. Also, an easier cable installation
between the aircraft fuselage and the TM mounted on
the landing gear is needed. In a future implementation, the ATRU can be replaced with an active bidirectional converter for feeding the regenerated power
from the dynamic braking back to the bus. This will
further reduce the brake wear and improve the overall
energy use.
xx
The WACU architecture uses a three-phase active
bridge arranged as a two-level inverter. The control
algorithms are field-oriented and vector-control
based for an optimized performance of the TM. The

Figure 17. The TM assembly integrated on the landing gear.

IEEE Elec trific ation Magazine / D EC EM BE R 2 0 1 7

Table of Contents for the Digital Edition of IEEE Electrification Magazine - December 2017