The HPD (Hybrid Performance Development) is a petrol/electric powered MG TF featuring a combined output of 200PS deployed through its four road wheels. MIRA engineers worked with MG Rover Group to produce the ‘200 HPD’ specification, derived from the popular MG TF sports car, producing both functional and environmental benefits.
The 200 HPD was designed as an enhanced performance car that anticipated environmental requirements, while expanding the sports car driving experience. The car achieves this with ‘responsible performance’ where the innovative hybrid solution sharpens acceleration, at no expense in tailpipe emissions, yet also offers customer benefits like all-wheel-drive traction and the low-speed clutchless operation of ‘City mode’.
Powertrain
Whilst a CVT was very useful for the prototype, it was to be eliminated by specifying more appropriate electric motors for the production solution.
Aerodynamics and thermal management
MIRA was able to improve the vehicle's cooling performance and package a smaller radiator.
Similarly our aerodynamicists were able to introduce stylish aerodynamic devices delivering zero lift, whilst trimming 10% of the drag.
Suspension
The improved performance required up-rated suspension.
MIRA used CAE to maximum advantage; applying one package for all component and packaging design and FE analysis.
We used a rapid prototype route to achieve; CAD Model to cast parts in 1 week!
All-Wheel Drive
A parallel hybrid drive train,was selected i.e. the internal combustion engine drives one set of wheels, and the electric motor the other. This provides optional low speed four-wheel drive or, at the other extreme of the envelope, enables us to tune handling characteristics at high speed. However primarily it was used to enhance the burst acceleration performance of the MG TF.
MG TF 200 HPD - Technical Specification:
K Series 160Ps, 1.8-litre VVC petrol engine driving rear wheels
40Ps high-output electric motor driving front wheels, through CVT drive train
Engine driven generator
Hawker SBS8 battery pack delivers 72v at 400 amps
BRUSA BRMD 506 motor controller
Mathworks XPC vehicle management
Performance Summary:
Sprint power increased from 160 to 200Ps
0-60mph time improved from 6.9 to sub 6.0 seconds
Aerodynamic Cd 0.32, zero front & rear lift
50 / 50 weight distribution
Additional Customer Delight Features:
All wheel drive traction, maximum tractive effort and ‘low mu’ handling
‘Hotshift’ delivers continuous power through front wheels during gear changes
‘City mode’ feature enables relaxed urban motoring using electric front drivetrain
Further details on MIRA's thinking behind the MG-TF HPD can be found in this article:
