Neural network-based robust actuator fault diagnosis for a non-linear multi-tank system
Marcin Mrugalski1, Marcel Luzar1, Marcin Pazera1
1Institute of Control and Computation Engineering, University of Zielona Góra, ul. Podgórna 50, 65-246 Zielona Góra, Poland.
ISA Transactions
|February 4, 2016
Summary
This study introduces a robust method for diagnosing actuator faults in non-linear systems using recurrent neural networks and H∞ observers. The approach ensures accurate fault estimation for fault-tolerant control applications.
Area of Science:
- Control Systems Engineering
- Non-linear Dynamics
- Fault Diagnosis
Background:
- Dynamic non-linear systems are susceptible to actuator faults, impacting operational reliability.
- Existing fault diagnosis methods often struggle with robustness and handling complex non-linear dynamics.
Purpose of the Study:
- To develop a robust actuator fault diagnosis method for dynamic non-linear systems.
- To design an unknown input observer capable of estimating actuator faults under uncertainty.
Main Methods:
- Modeling the non-linear system using recurrent neural networks (RNNs).
- Transforming the RNN model into a linear parameter varying (LPV) form.
- Designing a robust unknown input observer within the H∞ framework.
Main Results:
- The proposed observer achieves a prescribed disturbance attenuation level for actuator fault estimation error.
- Guaranteed convergence of the observer dynamics is demonstrated.
- The method enables accurate actuator fault estimation.
Conclusions:
- The developed robust unknown input observer effectively diagnoses actuator faults in non-linear systems.
- The approach provides a foundation for implementing fault-tolerant control strategies.
- The RNN-to-LPV transformation facilitates robust observer design for complex systems.
Related Concept Videos
Multimachine Stability
621
Multimachine stability analysis is crucial for understanding the dynamics and stability of power systems with multiple synchronous machines. The objective is to solve the swing equations for a network of M machines connected to an N-bus power system.
In analyzing the system, the nodal equations represent the relationship between bus voltages, machine voltages, and machine currents. The nodal equation is given by:
In analyzing the system, the nodal equations represent the relationship between bus voltages, machine voltages, and machine currents. The nodal equation is given by:
621
Multi-input and Multi-variable systems
461
Cruise control systems in cars are designed as multi-input systems to maintain a driver's desired speed while compensating for external disturbances such as changes in terrain. The block diagram for a cruise control system typically includes two main inputs: the desired speed set by the driver and any external disturbances, such as the incline of the road. By adjusting the engine throttle, the system maintains the vehicle's speed as close to the desired value as possible.
In the absence of...
In the absence of...
461
Linear Approximation in Frequency Domain
424
Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
424
Feedback control systems
790
Feedback control systems are categorized in various ways based on their design, analysis, and signal types.
Linear feedback systems are theoretical models that simplify analysis and design. These systems operate under the principle that their output is directly proportional to their input within certain ranges. For instance, an amplifier in a control system behaves linearly as long as the input signal remains within a specific range. However, most physical systems exhibit inherent nonlinearity...
Linear feedback systems are theoretical models that simplify analysis and design. These systems operate under the principle that their output is directly proportional to their input within certain ranges. For instance, an amplifier in a control system behaves linearly as long as the input signal remains within a specific range. However, most physical systems exhibit inherent nonlinearity...
790
Control System Problem
485
In an open-loop system, such as a basic thermostat, the poles of the transfer function influence the system's response but do not determine its stability. However, when feedback is introduced to form a closed-loop system, such as an advanced thermostat that adjusts heating based on room temperature, stability is governed by the new poles of the closed-loop transfer function.
When forming a closed-loop system, issues can arise if the poles cross into the unstable region, leading to potential...
When forming a closed-loop system, issues can arise if the poles cross into the unstable region, leading to potential...
485
Linear Approximation in Time Domain
397
Nonlinear systems often require sophisticated approaches for accurate modeling and analysis, with state-space representation being particularly effective. This method is especially useful for systems where variables and parameters vary with time or operating conditions, such as in a simple pendulum or a translational mechanical system with nonlinear springs.
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
397

