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Discrete state space modeling and control of nonlinear unknown systems.
1Department of Electrical and Electronics Engineering, Ege University, 35100 Bornova, Izmir, Turkey.
ISA Transactions
|August 28, 2013
Summary
A new discrete state-space neural network (DSSNN) models nonlinear systems. This approach integrates neural networks with conventional control, enabling linear model derivation for industrial applications.
Area of Science:
- Control Systems Engineering
- Artificial Intelligence
- Nonlinear System Modeling
Background:
- Industrial modeling and control of nonlinear systems present significant challenges.
- Conventional techniques often struggle with unknown nonlinear dynamics.
- Accurate system modeling is crucial for effective control design.
Purpose of the Study:
- To propose a novel procedure for designing industrial modeling and control systems for nonlinear unknown systems.
- To develop a new recurrent neural network architecture for discrete-time state-space representation.
- To integrate neural network-based models with conventional control design techniques.
Main Methods:
- A discrete state-space neural network (DSSNN) was constructed to represent nonlinear dynamical systems.
- Training was performed using the back-propagation through time (BPTT) algorithm and Levenberg-Marquardt (LM) optimization.
- A linearization procedure derived linear state-space models from the DSSNN for analysis and controller design.
Main Results:
- The DSSNN successfully obtained discrete-time state-space representations of nonlinear systems.
- Linear state-space models were derived, allowing examination of controllability, observability, and stability.
- State feedback controllers (LQR, pole placement) and observers were designed and validated for SISO and MIMO systems.
Conclusions:
- The proposed DSSNN procedure effectively models and facilitates control design for nonlinear unknown systems.
- Integration of neural networks with conventional methods offers a powerful approach for industrial control.
- The method demonstrated robust performance in both single- and multiple-input, multiple-output nonlinear control problems.
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