A. V. Kostylev

Optimization of starting process of the frequency controlled induction motor

The article deals with optimal control problem of induction motor during starting process. The method of genetic algorithm is offered as method for solution of the problem. Application of this method in order to form starting process of the induction squirrel-cage motor is examined.

Toward the evaluation of the influence of temperature fluctuations on the durability of the stator winding insulation of asynchronous motors in random mode loading

The influence of the stator winding temperature oscillation on the insulation-aging rate of the asynchronous motors stator winding in random mode loading is discussed. It is shown that under certain parameters of the random mode insulation durability can significantly decrease, wherein the widely used average loss method gives the evaluation of the motor thermal state with a substantial error.

Some aspects of the reliability increasing of the transport electric drives

The problem of the increasing reliability of the electric drives of transport vehicles which are characterized by random load duties is discussed. It is noted that in such modes of operation the temperature oscillations substantially influence on the insulation aging rate of the motor winding. It is shown that under certain parameters of the random load the insulation durability can significantly decrease, and the well known average loss method gives the evaluation of the motor thermal state with a substantial error. It is offered the method of motor selection and verifying on the stage of the electric drive design which allows to take into account influence of the temperature oscillations on the durability of the motor winding insulation. The necessity the evaluation of the average insulation aging rate and of residual thermal resource with the aim of the reliability increasing and longevity of the motor is substantiated.

Energy consumption optimization during starting of thyristor voltage converter-induction motor system

The paper deals with optimization of energy consumption during start in soft-start systems based on thyristor voltage converter and induction motor (TVC-IM). It is shown that the definition of optimum voltage ramp provides the 10-15% reducing of losses in compare with direct start. The method of voltage ramp optimization based on genetic algorithm is proposed

Some peculiarities of the simulation of electric drives with random mode loading

The paper considers some features reflected by simulation of electric drives operated in the random load modes. It is shown that the distribution laws for losses and the torque are essentially different. I.e., when modeling random modes of electric drive it is impossible to transfer the distribution law of the motor load, which is characterized by the motor torque, to the motor loss distribution. It is also shown that the value of the standard process deviation can significantly differ from the standard deviation of the amplitudes of this process; the difference can be either downwards or upwards depending on the cyclic duration factor and mathematical expectation of the amplitude. The influence of the torque limitation on probability density functions of load and losses was considered. The distribution law in the absence of the torque limitation and with regard to the impact of these limitations can result in different values of mathematical expectations and variances.

Evaluation of dynamic properties of the TEFC induction motors thermal models

Paper is devoted to research the dynamics of thermodynamic models for Totally Enclosed Fan-Cooled (TEFC) induction motors on the basis of the thermal lumped circuits. Clusterization a series of TEFC motors motors for general industrial application was performed. It allowed to group motors into clusters with consimilar parameter vectors of 5-node thermodynamic model. With using a method of genetic algorithms was carried out determination of the parameters of generalized 5-node thermal models corresponding to different clusters. An approach is proposed which allowing carry out a general analysis of the dynamic properties TEFC motors. With the use of frequency response for thermal models was revealed the actual area for gain values over a channel from the motor torque to the stator winding temperature for typical TEFC motors with mesh windings. The possibility of using the obtained thermal models to evaluate the influence of temperature fluctuations on the insulation resource expenditure acceleration was shown.

The use of cluster analysis for the synthesis of optimal frequency control law for induction drive

The problem of the starting process optimization of frequency controlled induction motor is discussed. The using of the specially synthesized frequency u/f control law is proposed. The concept of synthesis of the control law on the criterion of minimum motor heating is described. The simplified synthesis of the control law based on neural clustering for motors with similar parameters is considered. Simulated and experimental results are given.

The application of cluster analysis for the synthesis of optimal frequency control law for induction drive

The problem of the starting process optimization of frequency controlled induction motor is discussed. The using of the specially synthesized frequency u/f control law is proposed. The article describes the concept of synthesis of the control law on the criterion of minimum motor heating. The simplified synthesis of the control law based on neural clustering for motors with similar parameters is considered. Simulated and experimental results are given.

Influence of heating and voltage drop restrictions on starting process of thyristor voltage converter - Induction motor system

The paper deals with some aspects of soft starter application. Influence of heating and voltage drop restrictions on starting process are discussed. It is shown that there is an area of the correct application of soft starter.

Digital prediction control of electrical drive using neural network

The design method of predictive control systems which can be applied to control stator currents of induction motor is described. The results of application of artificial neural network predictor are presented. Simulation results are given.