Simulink Control Design™ - MathWorks

AirCharge  =  p 1 ×EngineSpeed + p 2 ×ManifoldPressure + p 3 ×(M

+ p 4 ×ManifoldPressure×EngineSpeed + p 5

If measured data for internal signals is not available, use simulation data from the

original model to compute the unknown parameters p 1 , p 2 , p 3 , p 4 , and p 5 using a least

squares fitting technique.

When you have measured data for internal signals, you can use the Simulink Design

Optimization™ software to compute the unknown parameters. See “Engine Speed Model

Parameter Estimation” (Simulink Design Optimization) to learn more about computing

model parameters, linearizing this approximated model, and designing a feedback

controlled for the linear model.

The next figure compares the simulations of the original event-based model and the

approximated model. Each of the pulses corresponds to a step change in the engine

speed. The size of the step change is between 1500 and 5500. Thus, you can use the

approximated model to accurately simulate and linearize the engine between 1500 RPM

and 5500 RPM.

2 Linearization