R. Rinkevičienė

Model of a Sensorless Induction Drive

The paper deals with modeling, simulation and analysis of speed observer for induction drive. Mathematical model of observer is presented and its computer model is elaborated. Speed measurement results are compared with those obtained during simulations with induction motor model. Development and implementation of speed observer requires measurement of motor current and supply voltage. Simulated values of current and voltage are used in the proposed observer model instead of the real ones. Model of induction motor is developed on the basis of motor equations in stationary reference frame. Model of observer relies on nonlinear differential equations, describing performance of induction motor, additionally making use of the space-vector theory. The speed observer developed by means of direct synthesis from state equations is robust with respect to parameter and load variations.

Mechatronic Systems with Linear Induction Motors of Dampers

The purpose of the paper is, from the view of system engineering, to investigate mechatronic systems with uncontrolled or pulse controlled dampers that are equipped with a linear induction motor (LIM), the secondary element of which appears as a moving element of a damper. The main technological parameters determining the requirements for linear induction drives applied in the automatic protection and technological process control systems were investigated. Methods to investigate electromagnetic, electromechanical and thermal dynamic processes at pulse control of large cross-area dampers were proposed, and application of results of the investigation was considered.

Modeling of a Mechatronic System with the AC Induction Motor Supplied by the Frequency Converter

A model of the AC induction motor, which allows us to analyze all operation modes of motor supplied by the frequency converter, has been developed. A simulation of the inverter of the frequency converter and the AC induction motor interaction on the basis of the developed motor model, using software MATLAB, was performed and a motor regenerative braking mode was investigated. The results of investigation are used for the development of fault protection of the inverter.