Rotor Induction Motor Research Articles

The Industrial IoT Control Design of Three Phase Induction Motor using Conventional V/F Method

Nowadays, the Internet of Things (IoT) is inseparable from the industrial revolution 4.0 and society 5.0. IoT allows all aspects to be connected at the same time. In industrial processes, the IoT controls the actuator and monitors the behavior system. Industrial IoT (IIoT) connected the Human Machine Interface (HMI) Haiwell C7S with the actuator (Schneider Altivar 12) and the controller (OMRON CP1E-NA20DRA). The communication between the variable speed drive and Haiwell C7S using Modbus protocol is connected with RS485. Schneider Altivar 12 is a variable-speed drive that controls the Induction Motor (IM) rotor speed using the conventional V/F method. The scalar control of IM controls supply frequency and voltage simultaneously. The success parameter of the proposed systems is a rotor speed response and voltage in various supply frequencies. The results show that the 5 Hz supply frequency makes the absolute error of rotor speed response 11.43% for tachometer measurement, 0.67% from VSD data, and 12.67% for rotary encoder measurement. This absolute error will decrease significantly when the supply frequency exceeds 20 Hz, or the rotor speed response exceeds 1200 rpm. The changes in the supply frequency change the voltage's magnitude. The voltage will increase proportionally, along with the increase in supply frequency.

Development of a Novel High Strength Aluminum-Cerium Based Rotor Alloy for Electric Vehicle Induction Motor Applications

<div class="section abstract"><div class="htmlview paragraph">To increase vehicle range, light weighting of electric vehicles has been extensively researched and implemented by using aluminum intensive solutions. With regards to traction motors, aluminum alloys that have a desired combination of high electrical conductivity and strength are required for high power output and efficiency. In this research, a novel Al-Ce based alloy, with minor additions of Si and Mg for strengthening, was investigated in different heat treatment tempers to maximize mechanical properties while maintaining a high electrical conductivity. This new alloy system appears to have addressed the classic conundrum of the inverse relationship of mechanical performance verses electrical conductivity for traditional aluminum alloy systems. The results suggest that the Al-Ce-Si-Mg alloy had yield strength in excess of 120 MPa and electrical conductivity of at least 50 %IACS in the T5 and T6 conditions. Simulations of a squirrel cage induction machine show that this combination of properties resulted in similar motor performance to other rotor Al alloys. As a result, the Al-Ce-Si-Mg alloy is a promising alternative to the near pure Al or Cu-based alloys that are currently used in induction motor rotor castings.</div></div>

A study of the dependence of the 3-phase cage motor maximum torque on the centroid of the rotor bar section

The paper investigates the relative influence of the centroid of the three-phase squirrel cage induction motor rotor bar cross section, on the breakdown (maximum) torque of the machine. The influence of the angle of taper, the top width and the radial depth of the bar section, as established design variables, were also investigated so as to properly situate the degree of influence of the centroid, in comparison; as far as the maximum torque is concerned. The machines were investigated in their steady state operating mode using the equivalent circuit method. The machine learning capabilities of the Least Square Support Vector Machine (LSSVM) was deployed to extract by prediction, information about the likely dependencies between the randomized block of the geometric variables and the maximum torque, and the captured information was stored using the Root Mean Square Error (RMSE) of predictions. The validated results show that the rotor leakage reactance – a part determinant of the maximum torque; tends to show some significant sensitivity to a design change in the centroid of the transverse section of the rotor bar.

Influence of squirrel cage induction rotor geometry in battery C-rating

An external rotor induction motor (ERIM) is designed to propel an electric two-wheeler with improved torque to current ratio. The torque of the optimized ERIM is significantly based on the rotor cage. The rotor’s specific permeance varies by varying the bar’s shape, increasing the motor’s torque. Likewise, maintaining the flux density below the saturation state keeps the current low. This research work proposes and studies various rotor bar shapes to improve the torque to current ratio of the motor. The proposed bars are optimized with finite element analysis (for rotor bar shape selection) and a metaheuristic approach (for rotor cage sizing). Improvement of torque to current ratio reduces the discharge C-rating of the battery, being the source for the ERIM structure.

Introducing Improved Iterated Extended Kalman Filter (IIEKF) to Estimate the Rotor Rotational Speed, Rotor and Stator Resistances of Induction Motors

This paper introduces the Improved Iterated Extended Kalman Filter (IIEKF) for estimating the rotational speed, rotor resistance, and stator resistance of three-phase induction motors (IMs). Two state-space models for estimating the variables are presented. An optimal estimation of rotational speed is obtained by introducing a data fusion approach. The effectiveness of the IIEKF in comparison with the Extended Kalman Filter (EKF), using experimental data and in a wide range of operating conditions, is shown.

A novel adaptive variable speed control strategy for wound rotor induction motors

A novel adaptive variable speed control strategy for wound rotor induction motors

Increasing the Performance of High-Speed Solid Rotor Induction Motor by Plunge Type Electrical Discharge Machining

Increasing the Performance of High-Speed Solid Rotor Induction Motor by Plunge Type Electrical Discharge Machining

Controlling power of short circuited induction motor via modern sensors without speed change

Short-circuited rotor induction motors are the most common and largest power consumers in industry. Therefore, it is necessary to find ways to ensure optimal performance of this type of motors and reduce their energy consumption. By this work, we will have the opportunity to automatically control the power of motors used in processes that do not have a stable operating mode. To perform this experiment, we use modern sensors and make special changes to the stator coil. Through our work, we create a special induction motor that is efficient, energy-saving and has a long service life. However it should be kept in mind that our developed motor is distinguished by its slightly complicated construction.

A novel adaptive variable speed control strategy for wound rotor induction motors

A new approach is proposed for the design of an adaptive variable speed controller for an induction motor. This design approach is based on a new model for induction motors in the (α/β) reference frame. The model state variables are constant in steady state and therefore enable the application of adaptive backstepping control design techniques to find controller equations and adaptation laws that ensure that the rotor speed and flux track their reference values despite significant changes in machine resistances and inductances due to temperature and magnetic saturation. The proposed controller is tested in simulation. Results show robust steady state and transient performances.

Performance Improvement of Induction Motor Controlled by Thyristor Chopper on the Rotor Side

In this paper, the performance characteristics of a variable-speed drive system with a wound rotor induction motor incorporating a 3-phase diode bridge rectifier - thyristor chopper with a modified commutation circuit system on the rotor side were studied. A DC equivalent circuit was used in the analysis of the motor-rectifier-chopper system and suitable equations have been derived for the determination of the system performance. The analytical results obtained are compared with those obtained experimentally to ascertain the validity of the system in practical applications. The results obtained indicate that a true variable speed drive system based on a thyristor chopper-controlled induction motor is successfully implemented. It is shown that the thyristor chopper control using the Hitachi commutation circuit permits the realization of a slip-ring induction motor as a variable speed and improved power factor. Also, the torque level obtained by the chopper control was found to be three times that obtained from conventional rotor resistance control at the same conditions.

Analysis the Effect of Using Synchronous Motor as a Synchronous Condenser for Power Factor Improvement of 3-Phase Cage Rotor Induction Motor

Synchronous motors working at a capacitive power factor of 0.8 are obtained by providing a 0ver excitation, meaning operation at a capacitive power factor to improve the power factor of the system when connected to an inductive load, as is the case with an induction motor. A synchronous motor that is over-excitation will act like a capacitor and suck up the current that lead the voltage. A synchronous motor that works without a load that is given over excitation will function as a synchronous compensator whose capacitive value can be adjusted. The condition of this synchronous compensator is installed on a cage rotor induction motor as a power factor improvement. The results of this study showed that the power factor value of the induction motor before installing the synchronous compensator was cos φ = 0.88 and the reactive power was 132,84 VAR, after installing the synchronous compen sator, cos φ = 0.91 to 0.99 and the reactive power was 68 VAR to 28,2 VARs

Experimental Loss Segregation in a Solid Rotor Induction Motor

Solid rotor induction motors (SRIMs) are asynchronous motors suited for high speed applications. This work presents an experimental case study where standard loss segregation procedures for induction motors are performed with a two-phase smooth solid rotor induction motor in order to verify their applicability. Even though the machine is supposed to operate at high frequency, the tests are performed at reduced frequency and voltage in order to avoid the effects of time harmonics. An adjustment in the separation of losses is proposed to contemplate the effects of the high no-load slip, and the behavior of the stray losses under high per-unit slip is analyzed in a load test. The test results are finally extrapolated for the rated condition.

The Commercialization of Medium-Voltage Induction Motor Rotor Diagnostics Equipment: Helping Prevent In-Service Failures of Induction Motors and Processes

The R&D process for commercializing diagnostics equipment for detecting rotor faults in MV induction motors is described in this article. This was the result of a five-year collaborative effort among three independent parties: the equipment end user, equipment developer/supplier, and a university research group, where the tasks performed by each party are summarized in <xref ref-type="fig" rid="fig1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Figure 1</xref> . The steps taken for successful development are given, along with a performance summary of the end product for which the first units have been in field use since 2017.

Fault Detection in Induction Motor Using Time Domain and Spectral Imaging-Based Transfer Learning Approach on Vibration Data.

The induction motor plays a vital role in industrial drive systems due to its robustness and easy maintenance but at the same time, it suffers electrical faults, mainly rotor faults such as broken rotor bars. Early shortcoming identification is needed to lessen support expenses and hinder high costs by using failure detection frameworks that give features extraction and pattern grouping of the issue to distinguish the failure in an induction motor using classification models. In this paper, the open-source dataset of the rotor with the broken bars in a three-phase induction motor available on the IEEE data port is used for fault classification. The study aims at fault identification under various loading conditions on the rotor of an induction motor by performing time, frequency, and time-frequency domain feature extraction. The extracted features are provided to the models to classify between the healthy and faulty rotors. The extracted features from the time and frequency domain give an accuracy of up to 87.52% and 88.58%, respectively, using the Random-Forest (RF) model. Whereas, in time-frequency, the Short Time Fourier Transform (STFT) based spectrograms provide reasonably high accuracy, around 97.67%, using a Convolutional Neural Network (CNN) based fine-tuned transfer learning framework for diagnosing induction motor rotor bar severity under various loading conditions.

Online Identification Strategy of Secondary Time Constant and Magnetizing Inductance for Linear Induction Motors

In this article, an online dual-parameter identification strategy for linear induction motors (LIMs) is investigated. Considering the influence of unique end effects in LIMs and the critical impact on control system performance, the magnetizing inductance and secondary time constant are chosen as the targets of estimation. Compared with rotary induction motors, the influence factors in LIMs are much more complex, which can heavily affect the parameter value especially for the high-speed condition. As a result, the online identification is vital for high performance applications. Based on the model reference adaptive system with magnetizing current as state variable, this article starts from the adaptive law of secondary time constant derived by Popov's criterion for hyperstability. Then, the physical significance and stable range are analyzed in details, based on which a handy magnetizing inductance identification method is combined. To further ensure the precision of estimation, one simplification scheme is specially designed. Besides, to eliminate the pure integrator, the derivatives of magnetizing current are chosen as the state variables. Finally, the dual-parameter identification system that utilizes only one PI controller and has low coupling property is constructed. Comprehensive simulation and experiments have fully demonstrated the effectiveness and superiorities of the proposed method.

Online induction motor rotor time constant estimation using perturbation-based extremum seeking control

&lt;p class="Abstract"&gt;&lt;span lang="EN-US"&gt;A novel online induction motor (IM) rotor time constant estimator based on a perturbation-based extremum seeking control (ESC) and model reference adaptive system (MRAS) is proposed. Since implementations of fieldoriented control (FOC) requires accurate values of IM parameters, such as rotor time constant, so accurate and robust on-line estimations of such parameters are crucial for any modern industrial IM drives. The proposed MRAS estimator employs ESC method to estimate the IM rotor resistance in various operating conditions. Meanwhile, since extremum seeking control is a model-free scheme, so it is robust to other IM parameter variations. The feasibility and effectiveness of the IM rotor resistance estimation by utilizing ESC scheme has been verified by simulation and experimental results. A 2.2 kW experimental setup has been implemented. &lt;/span&gt;&lt;/p&gt;

A Study on the Dynamics of an AC Induction Motor Rotor Based on the Analysis of Free Response at Impulse Excitation

Abstract This paper focuses on a topic frequently involved in the dynamics of transient phenomena on rotary machines driven by an AC induction motor supplied by a three-phase four-wire electrical system: the free response of the dynamic system mirrored in the torsional vibrations of its rotor. This dynamic system is reducible at a single degree of freedom system, equivalent of a spring-mass-damper but as a torsional vibratory system composed of the motor rotor (having a moment of inertia) the rotating magnetic field (having a torsional stiffness) and a hypothetical damper (generating a viscous damping mainly due to the air friction). This free response is useful mostly to characterize the transmissibility related to the conversion of information from mechanical to electrical power through this dynamic system. A simple computer-assisted setup is used to describe indirectly and to analyze the free response (generated when the motor is switched-on or after star to delta commutation sequence), using the active electrical power absorbed by the motor.

Nonlinear Model Order Reduction of Induction Motors Using Parameterized Cauer Ladder Network Method

In this study, we established the nonlinear model order reduction (MOR) of induction motors by parameterizing a multi-port Cauer ladder network (CLN). Appropriate parameters were selected to incorporate nonlinear magnetic characteristics. The parameterized multi-port CLN was applied to the transient analysis of a rotating induction motor. The proposed method reproduced the finite-element analysis results with various driving frequencies and slips. The parameterized multi-port CLN can effectively reduce the computation time for analyses requiring a large number of time steps.

Tracking of High-Order Stray-Flux Harmonics Under Starting for the Detection of Winding Asymmetries in Wound-Rotor Induction Motors

Wound rotor induction motors (WRIM) are widely used in a vast number of high output power industrial applications due to their capability of reaching high start torques while maintaining low inrush currents. Nonetheless, these machines are very prone to require early maintenance, and the possibility of presenting rotor winding asymmetry failures is high due to their more complex rotor circuit. Although some recent works have proposed techniques that overcome the drawbacks of conventional methods, an additional research effort for the development of alternative approaches able to enhance their performance and reliability is desirable. In this work, a new method for the diagnosis of rotor asymmetries in WRIM is presented. The proposed methodology is based on a feed-forward neural network fed by suitable fault severity indicators, which rely on the maximum energy density of higher order harmonics (amplified by the failure) at strategic regions of the time-frequency maps obtained from stray flux signals under startup transient. Experimental results for three different levels of rotor asymmetries in a 11-KW WRIM prove the reliability of the enhanced proposed system in comparison to conventional approaches that only rely on the main sideband fault-harmonic amplitudes.

COMPARATIVE ANALYSIS OF ELECTRIC MACHINES CHARACTERISTICS WITH PERMANENT MAGNETS FOR ELECTRIC VEHICLES AND WIND TURBINES

The results of a numerical and experimental study of an electric machine with cylindrical permanent magnets are presented. It is shown that if a squirrel-cage rotor in a standard induction motor is replaced by a rotor with permanent magnets, then a significant increase in the specific power of the electric machine can be obtained. Numerical studies and analyses of the characteristics of an electric machine with tangentially magnetized neodymium and ferrite magnets in the motor mode have been carried out. It is shown that in order to ensure maximum specific characteristics for use in electric vehicles, it is necessary to take into account the driving cycle and carry out liquid cooling of the electric motor. Also, a comparison of the characteristics obtained during testing of an experimental sample in the generator mode and the characteristics obtained in the calculation models was made. It is shown that the discrepancy between the calculated and experimental dependences for several values of the rotor speed is no more than 4%. The characteristics of the electrical machines under study were calculated using the Simcenter MagNet and Simcenter MotorSolve software packages. References 7, figures 6, tables 2.