Hybrid-Electric Vehicle Controller Development - Levels of Simulation and Verification

Rose-Hulman Institute of Technology is designing a power-split hybrid-electric vehicle that uses three power sources: a 70 kW Diesel engine that uses B-20 Diesel fuel and two 60 kW induction electric machines. All three power sources are connected through a planetary gear set (PGS). The electric machines move the vehicle in forward or reverse, act as motors or generators, and one of the motors is required to control the speed of the engine. When the three power sources are combined with a battery that must be maintained within specific operating limits, the system becomes a challenging control problem. This paper discusses the simulation methods used to design and verify the operation of the supervisory controller that controls all aspects of vehicle operation.

Four levels of simulation are discussed. (1) The development of a detailed vehicle plant model and hybrid vehicle supervisory controller (HVSC) for simulation. (2) Development of a model where the plant and HVSC run on a single real-time target to verify HVSC operation and observe the vehicle's performance in real-time. (3) Development of a model where the HVSC and plant run on separate real-time targets to evaluate the performance of the HVSC target for use in the vehicle. (4) Development of a model that includes communication and analog and digital I/O to verify communication protocols, simulate network latency, and simulate conversion delays.