文档介绍：Chapter 8
Parameter Identification By Impulse and Pulse Response
Li Shaoyuan
E-mail: ******@sjtu.
IMPULSE RESPONSE
Basic Principles
The main strategy of impulse-response identification is to obtain process transfer function models directly from experimental impulse-response data.
There is a direct relationship between a system’s transfer function and the moments of its theoretical impulse response.
One major disadvantage: the impulse function is difficult to implement in practice.
General Theory
By definition of the Laplace transform of a function, therefore:
Now, the power series expansion for e-st:
it es:
Identification of Simple Model Forms
The procedure, using the impulse-response approach, is now summarized.
1. Experimentally obtain the system’s impulse response.
2. From the impulse-response data, calculate the normalized moments
3. Postulate an approximate transfer function model.
4. Estimate the unknown parameters in the postulated, transfer function model by relating the transfer function to the moments.
First-Order Model
Second-Order Model
Second-Order-Plus-Single-Zero Model
First -Order-Plus-Time-Delay Model
For each observed experimental data point we may now write, using this expression:
which may be written together as:
Frequency Identification From Pulse Response