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  4. Approximation of fractional order differential-integral controllers by integer order transfer functions

Approximation of fractional order differential-integral controllers by integer order transfer functions

JCPEE.
2014;
Volume 4, Number 1
: pp. 29-32
Authors:
  1. Yaroslav Marushchak
  2. Bohdan Kopchak
1
Rzeszow Univesity of Technology
2
Lviv Polytechnic National University

The article is devoted to the approximation of fractional order differential-integral controllers by integer order transfer functions using the Oustaloup transformation. The dependence of the accuracy of practical approximation of fractional differential and integral units by the ratio of integer order polynomials on the Oustaloup transformation order has been examined. A modification of the Oustaloup method in which the order of the numerator polynomial is decremented by one has been proposed, and the recommendations for practical implementation of analog fractional order PI controllers have been made.

Oustaloup transformation
approximation
transfer function
fractional order.
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