Marburg, 18th March 2009 - MIRA recently completed the development of a retro-fit hybrid conversion which slashes fuel costs & lowers tailpipe emissions whilst retaining performance. The technology demonstrator was built around a popular b-segment car to show the potential of the technology. As a “plug-in hybrid” the vehicle can charge its batteries by running its engine or by plugging into the mains. The project, codenamed H4V (Hybrid 4wd Vehicle), was jointly funded by MIRA and the Energy Saving Trust in the UK and reached the following ambitious targets:
e40% reduction in CO2 during EC drive cycle giving 104gCO2/km
Fuel economy ≥ 64mpg (baseline 42.2mpg)
In charge depleting mode, 67gCO2/km and 99 mpg
EU4 compliant with EU5 capability
-8% Drag Coefficient due to lower rolling resistance
10% Engine efficiency improvement
Comparable performance to base vehicle
As extension of this project, MIRA decided to use VI-CarRealTime from VI-grade in order to have a fast and reliable vehicle model to connect with the control systems developed in the MATLAB/Simulink environment, and demonstrate novel vehicle dynamics features by using the rear mounted electric motors for All-Wheel-Drive (eAWD) and torque vectoring (eTV).
During the development of the control strategy for the MIRA H4V hybrid, a vehicle model in VI-CarRealTime has been used as plant model. Once the Software-in-the-Loop environment has been built in terms of vehicle plant model, eMotor plant model and eMotor controller, MIRA technical staff started running simulations in order to test dynamics behaviour under different working conditions (dry road and wet road) and to verify the ability of the hybrid system to provide traction control, under- & over-steer compensation, as well as stability control.
“We are pleased with the responses we get from the VI-CarRealTime model. The H4V project is very important to us at MIRA, since hybrid vehicles represent an important area of technology for the future. All automotive OEMs are investing heavily in this technology and the number of hybrid vehicles in the market is increasing every day. Having the possibility to use a reliable and fast vehicle model, from VI-CarRealTime, that is able to work together with the MATLAB/Simulink model of the electric motors, is vital for the success of the project. The fact that VI-CarRealTime can also work on hardware-in-the-loop systems is also important for future developments of the project.” says Simon Aldworth, Senior Engineer, MIRA Vehicle Dynamics.