Reduced order propulsion models for vehicle control and energy management

Engine output torque models have been applied to engine control, energy management and NVH development. Engine torque profile in a cycle is fixed after intake valves closing, so that a mean value engine model is suitable for those purposes considering accuracy and convenience. One of factors to affect model complexity is required cutoff frequency. Relationship between the frequency and engine cycle frequency is to be explained. An engine torque modeling methodology is to be proposed including a modeling approach applicable to a turbocharged engine in which a positive feedback loop exists in air intake process.