Performance Of Induction Machine Research Articles

Natural Fault-Tolerant VV-DTC for Healthy and Postfault Operation of an Asymmetrical Six-Phase Induction Machine Drive System With Single Neutral

Natural Fault-Tolerant VV-DTC for Healthy and Postfault Operation of an Asymmetrical Six-Phase Induction Machine Drive System With Single Neutral

Bearing fault diagnosis of induction machines using VMD-DWT and composite multiscale weighted permutation entropy

PurposeBearings play a critical role in the reliable operation of induction machines, and their failure can lead to significant operational challenges and downtime. Detecting and diagnosing these defects is imperative to ensure the longevity of induction machines and preventing costly downtime. The purpose of this paper is to develop a novel approach for diagnosis of bearing faults in induction machine.Design/methodology/approachTo identify the different fault states of the bearing with accurately and efficiently in this paper, the original bearing vibration signal is first decomposed into several intrinsic mode functions (IMFs) using variational mode decomposition (VMD). The IMFs that contain more noise information are selected using the Pearson correlation coefficient. Subsequently, discrete wavelet transform (DWT) is used to filter the noisy IMFs. Second, the composite multiscale weighted permutation entropy (CMWPE) of each component is calculated to form the features vector. Finally, the features vector is reduced using the locality-sensitive discriminant analysis algorithm, to be fed into the support vector machine model for training and classification.FindingsThe obtained results showed the ability of the VMD_DWT algorithm to reduce the noise of raw vibration signals. It also demonstrated that the proposed method can effectively extract different fault features from vibration signals.Originality/valueThis study suggested a new VMD_DWT method to reduce the noise of the bearing vibration signal. The proposed approach for bearing fault diagnosis of induction machine based on VMD-DWT and CMWPE is highly effective. Its effectiveness has been verified using experimental data.

Analysis of pole pair number impact on single-sided linear induction machine performances

This paper presents a parametric study of linear induction motor for design purpose. The chosen mathematical model uses a 2D formulation with magnetic vector potential A. The implementation of the model is carried out with the finite element method on the free platform Gmsh-GetDP. Circuit model is coupled to FE model so that constant voltage supply mode can be considered. This work aims to highlight the effect of the pole pair number on the characteristics and the performances of the linear induction machine through two numerical models associated to an analytical one. Furthermore, the study shows the effect of the pole pair number on the phase imbalance and the spatial harmonic spectrum of the machine. Reducing this imbalance and higher order harmonics presence will increase machine performances.

Assessing the impact of magnetic circuit corrosion on the magnetic performance of induction machines

Assessing the impact of magnetic circuit corrosion on the magnetic performance of induction machines

Excitation Control of Brushless Induction Excited Synchronous Motor with Induction Machine Operating in Deep-Plugging Mode

Abstract The popularity of electrified transportation is rising at a sharp pace due to environmental concerns over internal combustion (IC) engines. Researchers are nowadays looking for a brushless and permanent magnet (PM)-less solution for electric vehicle (EV) motors. Wound-field synchronous motor (WFSM) is a potential solution for EVs and is being used in Renault Zoe EV and BMW iX3 e-Drive models. A Brushless Induction excited Synchronous Motor (BINSYM) is a WFSM where the exciter, an induction machine (IM), is embedded inside the synchronous machine (SM) frame. Two machines (SM and IM) are configured for different numbers of poles to achieve magnetic decoupling, which facilitates independent control of both machines. The purpose of IM is to maintain the excitation requirement of SM. The IM is controlled in deep-plugging mode at a constant slip frequency over the entire speed range to minimise its reactive power demand. The maximum torque per ampere (MTPA) and root mean square (rms) current minimisation algorithms are used to control the SM. Simulation of the BINSYM-based system under dynamic conditions (MTPA with varying field current and load transient) has been carried out in MATLAB/Simulink to validate the control strategies. Experimental findings from the laboratory prototype machine closely match the simulation results.

Synchronous Generator Feeding DC Grid Having Brushless Excitation System With Induction Machine Operating in Deep Plugging Mode

This paper proposes a novel excitation control for a recently proposed synchronous generator (SG) entitled Brushless Induction Excited Synchronous Generator (BINSYG) for wind energy applications. In BINSYG, one SG and another Induction machine (IM) are embedded in the same machine frame to make the overall system brushless. Here, IM acts as the excitation machine and regulates the dc excitation for SG by rectifying the rotor-induced currents through a rotating rectifier. SG feeds power to dc grid via a two-level six-switch Voltage Source Rectifier that is operated at unity power factor at the SG terminal. The excitation developed by IM is regulated using a new frequency modulation control strategy for a two-level Voltage Source Inverter connected to the stator of IM. The excitation machine helps operate SG at variable wind speeds with reduced flux distortions. The proposed system is speed/position sensorless and controlled without using any voltage or current sensors on the IM side. The system with its proposed control algorithm is modeled in MATLAB/Simulink and experimental verification for a small-scale laboratory prototype BINSYG feeding power to a 220 V dc grid are presented to validate the effectiveness of the controller.

A Two-Step Continuous-Control-Set MPC for Modular Multilevel Converters Operating With Variable Output Voltage and Frequency

This paper presents a new enhanced single-stage two-step Continuous Control Set Model Predictive Control (CCS-MPC) algorithm, for Modular Multilevel Converters (MMCs) operating with variable output frequency at the AC port. The proposed two-step CCS-MPC allows the implementation of feed-forward compensation of the one-step ahead perturbations at the AC side, using an algorithm based on the Moore-Penrose pseudoinverse matrix. Limitations of the current and voltages in the MMC clusters are implemented to avoid overmodulation and overcurrents, being the solution of the constrained CCS-MPC online solved using the active-set method. Without losing generality, the experimental validation of the single-stage CCS-MPC is performed using an 18-cell MMC prototype, driving a 7.5 kW cage induction machine operating in a wide speed range. A dSPACE MicroLabBox platform is used to control the MMC-based drive by implementing the CCS-MPC algorithm, the modulation stage and the active-set method. It is experimentally demonstrated that the compensation of the low-frequency perturbations allows a considerable reduction in the required circulating currents at the low-frequency operation of the drive. Reduction in the capacitor voltage ripple, improved efficiency, and a smaller Total Harmonic Distortion (THD) in the output currents are also achieved with the proposed single-stage two-step CCS-MPC.

A New Post-Fault Reconfiguration Strategy under Open-Phase Operation Conditions of Asymmetrical Double-Star Induction Machines

The fault tolerance proprieties of multiphase induction machines make them candidate technologies for future electrified transport systems. Indeed, the use of multiphase drives is primarily recommended for their redundancy, which allows them to handle increasing power demands as well as provide fault-tolerant operation. One of the most common failures in polyphase induction machines is open-phase fault (OPF). Under this degraded mode, machine performance deteriorates with increased torque ripples and copper losses. This work investigates the fault-tolerant operation of dual star induction machines (DSIM) with two connected neutral points in which a new post-fault operation technique is introduced to manage the OPFs. The machine was modeled on the natural reference frame, and no transformations were used. The phase opening is caused by inserting a high-value resistor in series with the faulty phase, which cancels the current flowing in the latter. A post-fault reconfiguration strategy that reorganizes the power converter in order to cancel torque ripples by exploiting the principle of multi-biphase modeling of the DSIM is proposed. The performance of the proposed reconfiguration strategy was verified through detailed simulation results.

3상 유도기의 전동 운전과 발전 운전 모드에서의 무효전력 특성 분석

Induction machines can be operated as motors or generators near synchronous speed and it must be continuously receive the reactive power which is required for magnetization from the power supply side to maintain the rotating magnetic field regardless of the operation modes. If an induction machine with the same output capacity is operated as a motor or generator, the magnitude of the active power in each operation mode is different each other because the input and output are opposite to each other. When the active power changes, the reactive power also fluctuates, but the reactive power is slightly higher when operated as generator than when operated as motor. This is the reason why the power factor is slightly lower when the induction machine is operated as a generator than when it is operated as a motor. In this study, the magnitude of reactive power were calculated at each operation modes and analyzed how the ratio of reactive power changes when operated as a motor and as a generator for each capacity of the induction machine. The results are expected to be used as design reference data for selecting the optimal capacity of capacitors to improve the power factor in motor and generator operation of induction machines in the future.

Operating of DSIM without Current and Speed Sensors Controlled by ADRC Control

This paper presents an operation of the double start induction machine (DSIM) without current and speed sensors controlled by active disturbance rejection control (ADRC). The operation of the machine, without current and speed sensors, is an economic and simple method. The main advantages of this method are the reconstruction of stator current phases and rotor speed using only one DC voltage. The method is very simple and effective. It is based on the information provided by a DC voltage and the switching states of the converters to reconstruct the stator voltages. After we use two voltages observers to estimate the current stator and the rotor speed. The performance and the effectiveness of this method are verified under different conditions of simulations in MATLAB/Simulink. The results of the simulation prove the ability of this method to produce the same performances of DSIM with the current and speed sensors.

Comparative Study of Permanent Magnet, Conventional, and Advanced Induction Machines for Traction Applications

This paper investigates and compares the torque-generating capabilities and electromagnetic performance of advanced non-overlapping winding induction machines (AIM), conventional induction machines (CIM), and interior-permanent magnet (IPM) machines for electric vehicle (EV) applications. All investigated machines are designed based on the specifications of the Toyota Prius 2010 IPM machine. The steady-state and flux-weakening performance characteristics are calculated by employing the 2D finite element method and MatLab, and the obtained results are quantitatively compared. Furthermore, the torque-generating capabilities of three machines are investigated for different electric loadings, and the machine having the highest torque-generating capability is determined as AIM. Moreover, the major parameters affecting the torque-generating capability, such as magnetic saturation and magnet demagnetization, are examined in depth.

Modeling and Diagnosis of Induction Machines Operating under Open-Phase Fault

Modeling and Diagnosis of Induction Machines Operating under Open-Phase Fault

Effects of high-order space harmonics on the operation of five-phase induction machines under unbalance

The paper addresses the effects of high-order space harmonics on the steady-state performance of five-phase induction machines operating under unbalance. We show that the airgap harmonic fields with orders higher than three, although usually disregarded, can produce a significant increase in the torque pulsation and in the Joule losses. We propose a model based on symmetric components which is used to demonstrate that the field produced by each rotor harmonic current is related to two stator sequence currents. Further, the proposed model allows determining additional losses and harmonic torques produced by airgap harmonic fields with orders higher than three, which up to now have not been addressed elsewhere. As a case study, we applied the model to two five-phase induction machines with different designs and assessed the influence of high space harmonics under operation at steady state with one open phase in the stator. The model has been validated by comparing analytical results with results obtained through finite element analysis. Finally, the model validation was also based on experimental results obtained from tests with two prototypes under many different conditions.

The Performance of Induction Machines

Induction machines are one of the most important technical applications for both the industrial world and private use [...]

Velocity Sensor Fault-Tolerant Controller for Induction Machine Using Intelligent Voting Algorithm

Nowadays, induction machines (IMs) are widely used in industrial and transportation applications (electric or hybrid ground vehicle or aerospace actuators) thanks to their significant advantages in comparison to other technologies. Indeed, there is a large demand for IMs because of their reliability, robustness, and cost-effectiveness. The objective of this paper is to improve the reliability and performance of the three-phase induction machine in case of mechanical sensor failure. Moreover, this paper will discuss the development and proposal of a fault-tolerant controller (FTC), based on the combination of a vector controller, two virtual sensors (an extended Kalman filter, or EKF, and a sliding mode observer, or SMO) and a neural voting algorithm. In this approach, the vector controller is based on a new structure of a back-stepping sliding mode controller, which incorporates a double integral sliding surface to improve the performance of the induction machine in faulty operation mode. More specifically, this controller improves the machine performance in terms of having a fast response, fewer steady-state errors, and a robust performance in the existence of uncertainty. In addition, two voting algorithms are suggested in this approach. The first is based on neural networks, which are insensitive to parameter variations and do not need to set a threshold. The second one is based on fuzzy logic. Finally, validation is carried out by simulations in healthy and faulty operation modes to prove the feasibility of the proposed FTC.

Fast and Accurate Traction Induction Machine Performance Calculation Method for Integrated Onboard Charging in Vehicle to Grid Application

Reusing traction electric machine windings in electric vehicles as an integrated filtering inductor is a promising solution to reduce the size of the vehicle to grid (V2G) charging/discharging system. Obviously, the integrated inductors need to meet the requirements of traction and charging/discharging, which brings challenge for the design of traction machines. As one of the most popular traction electric machine types, the high-speed induction machine usually has large electrical time constant and consequently unacceptably long transient time in the design stage when finite element analysis is adopted. In this article, a method is proposed to quickly and accurately calculate the steady state performance of the induction machine by time-stepping transient magnetic finite element analysis. First, the stator current magnitude is ramped up from zero to full magnitude gradually to control the DC component in rotor flux and torque. Second, a multistep equivalent resistance method is adopted to decrease rotor time constant and suppress slot-tooth harmonic transient response. The proposed method can predict the FEA computation load before running the calculation, and it does not rely on the machine parameter and feedback signal. Its performance is tested by an example induction machine. The result shows that the proposed method can reduce the finite element calculation time of a high-speed operating point by 99%.

Parameter Estimation and Online Adaptation of Rotor Time Constant for Induction Motor Drive

The performance of a sensor-based rotor flux-oriented vector control induction machine drive is highly influenced by the estimated value of the rotor time constant/rotor resistance which varies continuously with temperature when it is driven with the variable loads. Therefore, to achieve accurate torque control, online tunning of the rotor time constant is necessary. This article proposes a novel and simple adaption technique to estimate the rotor time constant. In this proposed method, the reference model of the rotor flux vector is derived using the voltage model of the induction machine, which is independent of the rotor time constant. The current controller uses the model of the rotor flux vector that is derived using the current model of the induction machine. This current model is dependent on the rotor time constant. The error between the rotor flux vectors derived using the current model and the voltage model is minimized using the least-squares method. In this process, the rotor time constant is always tuned to its actual value. The article also presents a simple approach to estimate the parameters of induction machine like the stator resistance, the net leakage inductance, and the initial value of the rotor time constant in an offline mode at a standstill condition. To validate the proposed algorithm, two experimental prototypes are developed for two different power ratings of 3.7 and 67 kW. Experimental results from these prototypes confirm the effectiveness, reliability, and stability of the proposed algorithm both in the motoring and regenerative modes of operation. This method of the adaptation of the rotor time constant is simple and, therefore, useful for practicing engineers.

A comparative study for stator winding inter-turn short-circuit fault detection based on harmonic analysis of induction machine signatures

This article deals with inter-turn short-circuit fault detection in stator windings of squirrel cage induction machines. The main aim is to perform harmonic analysis of different electrical signatures namely the stator phase current, external magnetic flux and electromagnetic torque at different levels of mechanical load in order to develop an efficient fault detection approach of this kind of defect in induction machines. The proposed approach is based on the analysis of saturation related harmonics at rank 3k1fs, where k1 is an odd number, and magnetomotive force (MMF)-related harmonics at rank (6k2±1)fs, with k2=1,2,… in stator phase current and stray flux and harmonics at rank 2k2fs in electromagnetic torque. The amplitudes of these last harmonics in healthy condition are compared with 3% power supply unbalance, 16.6% (40 turns) and 33% (80 turns) levels of inter-turn short-circuit fault in frequency range from 0 Hz to 2500 Hz under different levels of mechanical load. Besides, the stand-still test is also investigated in this work. Simulation study is carried out based on 2.2kW squirrel cage IM using finite element method (FEM). This method provides accurate and inexpensive tool for evaluating the performance of induction machine under healthy and faulty conditions. The obtained results demonstrate that the stray flux is the most sensitive signature to the stator winding inter-turn short-circuit fault, and it is robust against the power supply unbalance in comparison with both stator current and electromagnetic torque.

Model calibration strategy for energy-efficient operation of induction machines

This contribution describes a novel calibration procedure for nonlinear induction machine models. It is based on measurements of the electrical quantities and the rotational speed, and uses additional measurements of the torque. Since the method uses quasi steady-state measurements, the calculations required for the model calibration can be performed with low computational costs in the frequency domain. Compared to the scientific state of the art, higher harmonics are taken into account in addition to the fundamental wave. The main goal of the parametrized model is to accurately capture the behavior of the induction machine in the vicinity of maximum efficiency operating points. Thus, the calibration strategy is tailored to these important operating points and allows to obtain a very high accuracy with a rather simple model. The proposed calibration procedure is verified by measurements on a test bench. It is shown that a high model accuracy can be achieved with the calibrated model.

Loss Investigation for Multiphase Induction Machine under Open-Circuit Fault Using Field–Circuit Coupling Finite Element Method

This paper focuses on the loss estimation for the multiphase induction machine (IM) operating under fault-tolerant conditions through the field–circuit coupling finite element method (FEM). Both one-phase and two-phase open-circuit faults of a seven-phase IM are researched, and different spatial positions of the fault phases are taken into consideration. The magnitudes and phase angles of the residual phase’s current are deduced based on the principle of equal magnitude of the residual phase currents and unchanged fundamental magnetic motive force (MMF). The magnetic fields’ coupling between the fundamental and harmonic planes is analyzed. Then, the time-stepping electromagnetic fields calculation of the seven-phase IM are carried out under the commercial software Simplorer–Maxwell environment. The transient and steady performance for both the health and fault conditions are obtained based on the rotor field-oriented control (RFOC) strategy. The Joule loss and iron loss are calculated for the torque step and slope responses. The seven-phase motor driving platform is established to verify the numerical calculation results. The proposed method is effective for predicting the loss and designing a reasonable operating range for multiphase IM operating under fault-tolerant conditions considering the thermal balance.