Sensorless control of DC drive using artificial neural network

DOI nefunkčníThe paper deals with the application of an artificial neural network in the speed control of the DC drive without a speed sensor. The sensorless control structure of the DC drive contains the feedforward artificial neural network for speed estimation. The sensorless DC drive was simulated in program Matlab with Simulink toolbox. The main goal was to find the simplest artificial neural network structure with minimum number of neurons, but simultaneously good control characteristics are required. Despite the used neural network, which is very simple, it was achieved satisfactory results. The simulation results were confirmed by measurement of important quantities on a laboratory stand with the DC drive.Web of Science111020

Speed estimation of induction motor using model reference adaptive system with Kalman filter

The paper deals with a speed estimation of the induction motor using observer with Model Reference Adaptive System and Kalman Filter. For simulation, Hardware in Loop Simulation method is used. The first part of the paper includes the mathematical description of the observer for the speed estimation of the induction motor. The second part describes Kalman filter. The third part describes Hardware in Loop Simulation method and its realization using multifunction card MF 624. In the last section of the paper, simulation results are shown for different changes of the induction motor speed which confirm high dynamic properties of the induction motor drive with sensorless control

Analysis of steady-state error in torque current component control of PMSM drive

The paper presents dynamic properties of a vector controlled permanent magnet synchronous motor drive supplied by a voltage source inverter. The paper deals with a control loop for the torque producing stator current. There is shown fundamental mathematical description for the vector control structure of the permanent magnet synchronous motor drive with respect to the current control for d-axis and q-axis of the rotor rotating coordinate system. The derivations of steadystate deviation for schemes with and without decoupling circuits are described for q-axis. The properties of both schemes are verified by MATLAB-SIMULINK program considering a lower and a higher value of inertia and by experimental measurements in our laboratory. The simulation and experimental results are presented and discussed at the end of the paper.Web of Science172463

An implementation of rotor speed observer for sensorless induction motor drive in case of machine parameter uncertainty

The paper describes observers using model reference adaptive system for sensorless induction motor drive with the pulse width modulator and the direct torque control under the circumstances of incorrect information of induction motor parameters. An approximation based on the definition of the Laplace transformation is used to obtain initial values of the parameters. These values are utilized to simulate sensorless control structures of the induction motor drive in Matlab-Simulink environment. Performance comparison of two typical observers is carried out at different speed areas and in presence of parameter uncertainty. A laboratory stand with the induction motor drive and load unit is set up to verify the properties of observers. Experimental results confirm the expected dynamic properties of selected observer

Speed estimators using stator resistance adaptation for sensorless induction motor drive

The paper describes speed estimators for a speed sensorless induction motor drive with the direct torque and flux control. However, the accuracy of the direct torque control depends on the correct information of the stator resistance, because its value varies with working conditions of the induction motor. Hence, a stator resistance adaptation is necessary. Two techniques were developed for solving this problem: model reference adaptive system based scheme and artificial neural network based scheme. At first, the sensorless control structures of the induction motor drive were implemented in Matlab-Simulink environment. Then, a comparison is done by evaluating the rotor speed difference. The simulation results confirm that speed estimators and adaptation techniques are simple to simulate and experiment. By comparison of both speed estimators and both adaptation techniques, the current based model reference adaptive system estimator with the artificial neural network based adaptation technique gives higher accuracy of the speed estimation

Third order low-pass filter using synthetic immittance elements with current conveyors

The paper deals with a theoretical proposal of the resulting circuit of the frequency filter using synthetic immittance elements of higher order with current conveyors. The text pays particular attention to design process of synthetic immittance elements, explains the principle of increasing of order, which is then reflected to the frequency filter order. The text then deals less with the theory of current conveyors, which has already been discussed, in detail, in previous papers. Universal current conveyor (UCC) is discussed more. This active element is used for the theoretical implementation of the synthetic element solution used in the frequency filter. The theoretical knowledge is then demonstrated in the design of 3rd order low-pass frequency filter. The final functionality of the proposed frequency filter circuit solution is validated by PSpice simulation

Novel Wien bridge oscillator design using functional block structure with current conveyors

The purpose of this paper is to generally present possibilities of the current conveyor use in the well-known active electronic circuits. Current conveyors are able to substitute all known active elements. This claim is supported by the fact, that four basic functional block structures can be realized by use of current conveyors - voltage-controlled voltage source, voltagecontrolled current source, current-controlled current source and current-controlled voltage source. The paper presents particular example of use of functional block structure with current conveyors in Wien bridge oscillator, where it successfully substitutes operational amplifier on the place of active element. Both theoretical formulae and design description are given. Finally, OrCAD PSpice simulation results are presented

Application of fuzzy logic in control of switched reluctance motor

The flux linkage of switched reluctance motor (SRM) depends on the stator current and position between the rotor and stator poles. The fact determines that during control of SRM current with the help of classical PI controllers in a wide regulation range unsatisfied results occur. The main reasons of the mentioned situation are big changes of the stator inductance depending on the stator current and rotor position. In a switched reluctance motor the stator phase inductance is a non-linear function of the stator phase current and rotor position. Fuzzy controller and fuzzy logic are generally non-linear systems; hence they can provide better performance in this case. Fuzzy controller is mostly presented as a direct fuzzy controller or as a system, which realizes continued changing parameters of other controller, so-called fuzzy supervisor. Referring to the usage of fuzzy logic as a supervisor of conventional PI controller in control of SRM possible improvement occurs

Second order low-pass and high-pass filter designs using method of synthetic immitance elements

The paper briefly describes the basics of frequency filter design method using synthetic immittance elements with current conveyors. An introduction of the paper explains the advantages and also disadvantages of using this method. Other chapters briefly introduce a design process of simple second order low-pass and high-pass filter. A theory of current conveyors is discussed too, because they are the basic building blocs of proposed synthetic element and also active frequency filters. Finally, the particular solutions of low-pass and high-pass filters are given and verified by OrCAD PSpice simulations