PhD Thesis - Cranfield University

Chapter 1
more than a century since its introduction, and decades since it was forced into near
oblivion, EVs have regained a strong global presence [3, 4]. Industry efforts, coupled with
paradigm shifts in transportation perspectives provide substantial grounds for continuing
EV research contributions. The viability of a purely electric vehicle as a future transportation
solution is perhaps arguable. The single limitation of current EVs compared to an ICE-
Hybrid EV is still the travel range. As a near future target, EVs will find definite niche
applications where short commuting distances or predefined routes dictate the vehicles’
range requirement [5].
Perhaps the EV or even the hybrid electric vehicle (HEV) is not the ultimate answer, it is
surely not the optimum solution but rather an interim one. However, the very effort to
diversify from the well-matured ICE based vehicles is a step forward towards sustainable
development. Optimistically, several new ideas will spring from the collective efforts of
many small but progressive research contributions.
1.2 The emerging area of Vehicle Power and Energy Management
As the future of electric and hybrid electric vehicles is evidently becoming promising [6, 7],
significant research efforts worldwide have been directed towards improving propulsion
systems and energy storage units [8]. In the course of vehicles becoming “More Electric” [9],
with increasing number of onboard electrically powered subsystems for both commercial
and military applications, the need to manage the vehicular power system is imperative.
Electrical loads for both traction and ancillary loads are expected to increase as the
automotive power system architecture shifts towards a more silicon rich environment [10].
The complex demand profiles anticipated by these dynamic loads require accurate and
optimised control of power flow and energy storage subsystems within the vehicle, thus
presents a technical challenge and opportunity for vehicular power and energy management
research.
In a broad sense, the term ‘Electric Vehicle’ can be identified with any vehicle with an
electrical propulsion system. This should encompass land, sea and air vehicles but in fact it
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