Michał Bartyś

Development and Application of Methods for Actuator Diagnosis in Industrial Control Systems (DAMADICS): A Benchmark Study

Abstract This paper provides the description and presentation of a new actuator benchmark for fault diagnosis studies developed in the framework of the EC-funded Research Training Network DAMADICS. The paper also introduces 3 special sessions of papers providing an evaluation of methods and results focussed on the benchmark problem. The benchmark is FDI method independent and based on an in-depth study of the phenomena that can lead to likely faults in valve actuator systems. The study uses a detailed consideration of the physics and electro-mechanical properties of the valve together with typical engineering requirements of a valve operating under challenging industrial conditions. The benchmark study is available on the internet at http://diag.mchtr.pw.edu.pl/damadics/ and provides a set of performance indices for evaluating the results.

Actuator Simulation of the DAMADICS Benchmark Actuator System

Abstract In the paper the simulation model of actuator consisting of spring-diaphragm pneumatic servomotor, intelligent positioner and control valve is presented. The model is particularly suited to compare and contrast a wide range of fault detection and isolation methods within a strongly oriented focus on application to industrial actuator examples. Using the model it is possible to simulate up to 19 incipient or abrupt faults of the actuator. The model is based on physical description and partly on engineering expertise. The parameters of the model were determined experimentally. Model was validated by application of real process data.

APPLICATION OF FUZZY LOGIC FAULT ISOLATION METHODS FOR ACTUATOR DIAGNOSIS

Abstract Four fuzzy logic fault isolation methods suitable for implementation in smart final control elements are proposed. The methods are suited for real time diagnostics applications considering computing power limitations typical for applications in intrinsically safe zones. The comparison of isolability features of presented algorithms is given in examples.

Smart Positioner with Fuzzy Based Fault Diagnosis

Abstract The decentralisation of the diagnostic tasks could be achieved when the automatic and technological equipment devices will be provided with class of smart autonomous diagnostic units. In this case the functions of the central diagnostic system may be simplified. This class may be represented by smart positioner with actuator fault diagnosis. In the paper an idea of smart positioner with actuator fuzzy based fault diagnosis is presented. The scheme of the residuum vector generation based on the fuzzy models is given, as well as with the scheme of diagnostics decision making procedure for the positioner.

Multiple Fault Isolation Algorithm Based on Binary Diagnostic Matrix

The problem of the isolation of the multiple faults based on binary diagnostic matrix (BDM) is addressed in this paper. A novel multiple fault isolation approach (MFI) based on binary diagnostic matrix is presented and discussed here. MFI algorithm was optimized in respect to its effectiveness. The theoretical background of MFI was presented. A multiple fault generator based on a matrix of paths was introduced and discussed. The computational complexity of the algorithm was estimated and contrasted with the known MUFIA algorithm. An example of MFI application for on-line diagnostics of a steam-water line of the power boiler was presented.

Fuzzy Logic Application for Diagnostic Reasoning

Abstract In the paper three different methods of diagnostic reasoning with application of fuzzy sets theory were briefly presented and discussed. Fuzzy logic application gives the opportunity of introducing diagnostic signal certainty degrees what is particularly important when taking into account industrial applications. The considerations were done under assumption of single faults. Fault symptom dynamic is not directly considered here. Time-to-diagnose and applicability aspects were chosen as a key factors for the comparison of the presented reasoning approaches. The advantages of serial-parallel diagnostic reasoning over either parallel or serial reasoning were underlined. Comparative examples of serial, parallel and serial-parallel reasoning were presented.

Application of Perceptron Neural Networks for Fault Detection

Abstract In the paper the investigation of chosen fault detection method based on neural network models for industrial applications is presented. The investigation was done based on the real data acquired from first stage of evaporation station of sugar factory. The non-linear perceptron MA-type models and perceptron ARMA-type models were examined. The only three-layer perceptron networks were investigated. It was shown that MA models have better fault detection performance compared to ARMA models.

Diagnostics of Industrial Processes in Decentralised Structures with Application of Fuzzy Logic

Abstract In the paper the problem of decomposition of the diagnostic system has been described. Principles of diagnostics in the decentralised hierarchic structure with the application of fuzzy logic have been given. The features and advantages of diagnostics of industrial processes in decentralised structures have been discussed. An industrial example of diagnostic reasoning in the decomposed structure has been presented.

Application of Information System Theory for Actuators Diagnosis

Abstract For actuator assembly consisting of: control valve, pneumatic linear servomotor and positioner the set of possible faults was defined. Fault related algorithms are given. For description of the faults-symptoms relations the information system theory was applied. The fault identification algorithms basing on the information system rules are given.

Unusual Application of the X3STEP Controller

The paper tackles a specific problem of the control engineering practice. The essence of the problem is the unusual application of the 3P class X3STEP controller for driving the continuous input final control elements. In this context, the paper is addressed particularly to practitioners and designers of control systems. The cost-effective and feasible solution of this problem was outlined in this paper. It is based on the introduction of a low cost hardware interface together with the software driver intended for the positioner of the final control element. The chosen results of performed simulations as well as announcement about pilot implementation in the secondary air control damper loop in the steam boiler of a power condense turbine finalize the paper.