This thesis describes research and development. work carried out
by the author into the control of traction and braking systems
on rail vehicles.
After a review of recent developments, the problem of. driving a
train under minimum-energy control subject·to timetable and
operational constraints is discussed. This is partitioned into
two sections. Firstly, target time and velocities for key pOints
on the journey are computed; these are communicated to or stored
on the train, together with route and vehicle data. Secondly,
an on-board digital system drives the train to each target
according to control algorithms which incorporate a predictorcorrector
module, whose function is to determine which of two
criteria of performance is to be used (minimum-energy when running
early or on-time, minimum-time when running late).
Most of the thesis is devoted to the analysis and design of the
train-borne control system. The general form of the optimal
control (of tractive or braking effort) is determined by the application
of Pontryagin's Maximum Principle over each section of the
journey. However, the moments of transition between the various
modes of control are calculated by a method which involves a lookahead
model in the predictor module, rather than by iterative
solution of the state and co-state equations .
An important aspect of the design is the dynamic response of the
braking SUb-system, which may include a substantial pneumatic
transport lag within the control loop. S-plane and z-plane design
procedures for the required discrete control algorithms to.achieve
a specified transient response are derived.
The thesis concludes with a chapter on the instrumentation required
for the train-borne control system.
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.