Simulink Control Design™ - MathWorks

Rate Conversion Method When to Use

Upsampling when possible,

Zero-Order Hold otherwise

Upsampling when possible,

Tustin otherwise

Upsampling when possible,

Tustin with Prewarping

otherwise

Upsample discrete states when

possible to ensure gain and phase

matching of upsampled dynamics. You

can only upsample when the new

sample time is an integer multiple of

the sample time of the original system.

Otherwise, the software uses the

alternate rate conversion method.

(^3) If you select either of the following rate conversion methods:

• Tustin with Prewarping


• Upsampling when possible, Tustin with Prewarping otherwise

then, in the Enter prewarp frequency field, specify the prewarp frequency.

To specify the rate conversion method at the command line, create a linearizeOptions

option set, and set the RateConversionMethod and PreWarpFreq options. For

example:

opt = linearizeOptions;

opt.RateConversionMethod = 'prewarp';

opt.PreWarpFreq = 100;

You can then use this option set with linearize or slLinearizer.

NoteIf you use a rate conversion method other than zero-order hold, the converted

states no longer have the same physical meaning as the original states. As a result, the

state names in the resulting LTI system are '?'.

See Also

Apps

Linear Analysis Tool

Functions

linearize | linearizeOptions

2 Linearization