A microprocessor control system system for a hybrid electric vehicle

There is a serious effort going on in this country and around the world to find an alternative to conventional vehicles. The most reasonable alternative is an Electric Vehicle (EV). However, there are many problems with implementing a pure EV commercially, including range, power, recharge time, and others. Because of these problems, Hybrid Electric Vehicles (HEV)s are gaining consideration. Since HEVs are a combination of current vehicles and EVs, they have the best features of each.

A microprocessor-based control system was developed to control an HEV developed at the University of Tennessee. The microprocessor used is a Motorola 68HC11. Programming of the microprocessor was accomplished in Motorola assembly language. The program monitors inputs from both the driver and the system and then controls a gasoline engine and generator pair in the vehicle and displays information to the driver. Interface circuits were developed to communicate between the microprocessor and the subsystems of the vehicle. Several different tests were run on the vehicle, including acceleration, constant speed, and braking tests. In all of the tests, the system responded properly and consistently.