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Open-Phase Fault Detection Method for Sensorless Five-Phase Induction Motor Drives with an Inverter Output Filter

Abstract

The paper presents the sensorless five-phase induction motor drive implementation with an inverter output filter with third harmonic injection. For the sensorless operation, the required observers are presented for the first and third harmonics with consideration of the inverter output filter. Moreover, the interaction of the observers and the control system is capable to handle a deactivation of one or two phases, which improves the reliability of the complete drive system. A new idea of online openphase fault detection is presented based on the frequency analysis of the estimated observer variables. The test setup, fault operation capabilities and an experimental verification of the proposed fault detection method are presented in the paper.

Open access
Application of Neural Networks and Axial Flux for the Detection of Stator and Rotor Faults of an Induction Motor

Abstract

The paper presents the possibility of using neural networks in the detection of stator and rotor electrical faults of induction motors. Fault detection and identification are based on the analysis of symptoms obtained from the fast Fourier transform of the voltage induced by an axial flux in a measurement coil. Neural network teaching and testing were performed in a MATLAB-Simulink environment. The effectiveness of various neural network structures to detect damage, its type (rotor or stator damage) and damage levels (number of rotor bars cracked or stator winding shorted circuits) is presented.

Open access
Acoustic Sensor for Detecting Intruders in Wild Environments

Abstract

The aim of this work is to develop a device capable to record multiple audio signals (in our case 4 audio signals from 4 microphones of the area) and transmit the information through a network for acoustic source localization. We briefly discuss the first two versions, then the HRTF (Head Related Transfer Function) version of the acoustic sensors is detailed. Experimental results for identifying sound sources are also presented.

Open access
Adaptive Nonlinear Control of A Synchronous Generator

Abstract

In this work, an adaptive nonlinear control method, was applied to a synchronous generator and we give some initial results on the adaptive control of nonlinear systems which are exactly input-output linearizable by state feedback. Parameters adaptation is used as a technique to robustify the exact cancelation of nonlinear terms, which is called for the linearization technique. The performance of the proposed adaptive nonlinear control scheme is demonstrated by simulation results. These results show that the proposed method achieves the same high dynamic performance as vector control.

Open access
Application of Super-Twisting Sliding Mode Controllers in Direct Field-Oriented Control System of Six-Phase Induction Motor: Experimental Studies

Abstract

This paper presents the direct field-oriented control (DFOC) method of six-phase induction motor with the application of super-twisting sliding mode algorithm. The mathematical model of the six-phase induction motor has been described. The descriptions of the space vector modulation (SVM) method and the super-twisting algorithm have been presented. The DFOC method with super-twisting sliding mode controllers has been described. The experimental studies of the DFOC method with super-twisting controllers have been performed, and the results of these studies are presented and discussed.

Open access
Comparative Stability Analysis of Stator Current Error-based Estimators of Induction Motor Speed

Abstract

This paper deals with the stability problem of three stator current error-based estimators of induction motor speed, especially in the regenerating operation mode. The stability of the adaptive full-order observer (AFO) and two model reference adaptive systems (MRASs) based on a stator current error (MRASCCand MRASCV) is briefly analysed, and the stability borders are determined and compared. It is shown that MRASCVspeed estimator is stable in the whole operation range including the regenerating mode without any modifications. The stability enhancement method for AFO and MRASCCestimators is described, and the solution for their stability improvement is proposed. Torque-speed characteristics of the analysed MRAStype estimators in a wide range of drive speed and load torque changes are given, as well as the behaviour of estimators during transients is compared. The theoretical analysis and simulation test results are validated by experimental tests.

Open access
A comparative study between four-level NSVM and three-level NSVM technique for a DFIG-based WECSs controlled by indirect vector control

Abstract

In this work, we present a comparative study between four-level neural space vector modulation (4L-NSVM) and three-level neural space vector modulation (3L-NSVM) technique in indirect vector control (IVC) of reactive and active power control of a doubly fed induction generator (DFIG) for wind energy conversion systems (WECSs). Two controls techniques using IVC-4L-NSVM and IVC-3L-NSVM are proposed and compared. The validity of the proposed control schemes is verified by simulation tests of a DFIG-based wind turbine system (WTSs). The stator active power, stator reactive power and rotor current is determined and compared in the above strategies. The obtained results showed that the proposed IVC with 4L-NSVM technique have reactive and stator active power with low powers ripples and low rotor current harmonic distortion than 3L-NSVM technique.

Open access
A Cost-Effective Resonant Switched-Capacitor DC-DC Boost Converter – Experimental Results and Feasibility Model

Abstract

This paper presents the results of experimental research of a resonant switched capacitor voltage multiplier in a cost-effective topology (CESCVM) with a limited number of active switches. In the charging mode of the switched capacitors, the converter utilizes only one active switch and a required number of diodes. Therefore, the cost of the converter is decreased as compared with that of a classical SCVM converter, owing to a lower number of switches and gate driver circuits, as well as a smaller PCB area. Moreover, the CESCVM has simpler control circuits and higher reliability. This paper presents the original experimental results of the operation of the CESCVM converter. A concept of the bootstrap supply of gate drivers of the flying switches is also examined.

Open access
Design of Helix Antenna for 9.2GHz in FEKO for FSO/RF Hybrid System Focused on Height of Helix

Abstract

Nowadays we are living in the ages of expansion of communication. The young generation depends on the online communications with other. Each of the devices is purposed to communication. Cloud data storage systems are available only with stable connection. Requirements are growing up to date. The answer on these requirements: the high speed of transmission, high level of security and wide bandwidth are optical communication systems. This system offers comparable features as optical system with physical optical fibers. But it has one big drawback. It is sensitivity to weather changes. We have to make backup link for case of outages. One part of design FSO/RF system in our case contains selection of appropriate type of RF antenna. We are looking for appropriate candidate. This paper is focused on analysis of helix antenna operating in non-licensed frequency range on 9.2GHz. The point of this paper is the examination of the impact of the height of helix designed antenna.

Open access
Dynamic Performance of Estimator-based Speed Sensorless Control of Induction Machines Using Extended and Unscented Kalman Filters

Abstract

This paper presents an estimator-based speed sensorless field-oriented control (FOC) method for induction machines, where the state estimator is based on a self-contained, non-linear model. This model characterises both the electrical and the mechanical behaviours of the machine and describes them with seven state variables. The state variables are estimated from the measured stator currents and from the known stator voltages by using an estimator algorithm. An important aspect is that one of the state variables is the load torque and, hence, it is also estimated by the estimator. Using this feature, the applied estimator-based speed sensorless control algorithm may be operated adequately besides varying load torque. In this work, two different variants of the control algorithm are developed based on the extended and the unscented Kalman filters (EKF, UKF) as state estimators. The dynamic performance of these variants is tested and compared using experiments and simulations. Results show that the variants have comparable performance in general, but the UKF-based control provides better performance if a stochastically varying load disturbance is present.

Open access