Tomas Skulavik

The Defuzzification Methods Influence on Fuzzy Control of Nuclear Reactor

This paper deals with the influence of the defuzzification methods on the quality of fuzzy control. There exist many defuzzification methods in theory. Each of them has its own benefits and application areas. The scope of this paper is focused only to the defuzzification methods available in Matlab Simulink environment. These are compared and evaluated using the integral quality criteria. The fuzzy PI controller was designed with normalized universes to simplify the tuning of controller parameters. The nuclear reactor model has been used as a reference system during experiments. The nuclear reactor model has been constructed using the Point kinetics model and the Thermal model. Step response characteristics of the closed loop control system were evaluated using integral criteria to compare available defuzzification methods. Finally the achieved results were briefly summarized.

Proposal of a Fuzzy Control System for Heat Transfer Using PLC

The article presents a fuzzy controller design for using PLC as a control system. The subject of controlling is a mathematical model of a heat exchanger modeled in Simulink. The control algorithm was developed and configurated in the FuzzyControl++ configuration tools for the automation of technical processes. The goal of the paper is to explore the possibilities to implement and realize the potential of fuzzy control in areas belonging to the domain of classical regulation. Model of the closed loop control system in virtual environment is used to perform multiple simulations to detect the system behavior under various conditions. It is concluded that the applied control strategies can offer same properties in progress of regulation and offer better approach to intuitive knowledge base design and configuration parameters of controller.

Fuzzy control of indirect heat exchanger implemented in Simulink

The article deals with designing a fuzzy controller for indirect heat exchanger in virtual environment. The fuzzy logic is used for controlling input flow of liquid with constant temperature to achieve the desired output temperature of the liquid. The goal of the paper is to explore the possibilities to implement and realize the potential of fuzzy control in areas belonging to the domain of classical regulation. The controlled system as well as the fuzzy controller was modeled in Matlab Simulink and multiple simulations were performed to detect the system behavior under various conditions. The recorded and analyzed simulation results will be used for implementation of the industrial controller utilising fuzzy logic.

The Study Into Potential Enhacement Of Metalworking Fluids Biodegradability By The Application Of O3/UV

Abstract The increase in mineralization and biodegradability of MWFs by ozone/ultraviolet in comparison with ozone were investigated. Studied were two similar synthetic fluids pre-treated by the combination of the O3/UV advanced oxidative method. Expectations that the pre-treatment could enhance biodegradability of the metalworking fluid were not confirmed. The combined oxidation process at the defined conditions resulted in 1-35 % decrease of the achieved primary degradation level. Samples were prepared from real concentrates and diluted to approximately 350 mg/L of TOC.

Systematic Approach to Factory Acceptance Test Planning

Abstract This paper deals with proposal of the basic frame of systematic approach to factory acceptance tests (FAT). The motivation of the presented research is briefly and concisely introduced in connection with relevant standards. Presented systematic approach to FAT is exhaustively explained using a case study example. The main results could be summarized as follows. In the first place is the analysis of approaches in the relevant research area, which is the life cycle of control systems on process level. Next is the proposal of the basic frame of systematic approach to planning, execution, evaluation and documenting of FAT and finally the detailed FAT plan specification. It is obvious that the presented proposal provide engineers with effective uniform methodics to deal with FAT, which could consequently lead to shortening the implementation phase of project life cycle.

Virtual model of an electro-hydraulic system

This paper deals with the design of model of electro-hydraulic system with failure simulation feature. The fundamental causes and effects of failures of electro-hydraulic system are summarized. Virtual Simulink model of electro-hydraulic system has been developed and implemented in compliance with performed FMEA (Failure Mode and Effects Analysis). Subsequent experimental part focuses to the simulation of selected failures on electro-hydraulic system model. The results of simulation of failures are shown in time response characteristics of monitored variables.

Steady State Response Simulation of a 2-D Micromirror in Simulink

Micromirrors fabricated by MEMS technology may be important sensing components in optical tracking systems used in many industrial applications. This paper deals with the analytical model of a 2-D gimbal mounted micromirror and with the simulation of a steady state response of the micromirror in Simulink. The model of a 2-D micromirror should be further used in a simulation of its dynamical behavior.