Performance Of Squirrel Cage Induction Motor Research Articles

Performance Analysis of Induction Motor using Ansys

Squirrel cage Induction motors are useful in constant speed and variable frequency drives applications because they are self starting and have high overload capacity. Though they are self starting, their design limits corresponding to torque should be large to meet the actual load conditions. To get optimum performance of motor, it needs unique design characteristics. Design of machines is a time consuming process. Proper methods are required for designing. ANSYS software is being used in recent times for designing electrical machines. In this paper, RMxprt tool box is used to design induction motor and its performance is analyzed using ANSYS Maxwell. In RMxprt, the induction motor's geometric model is designed and analyzed .In this model the machine rating is of 1100W with a rated speed of 1450 rpm and with rated voltage of 330V. With the help of this design, squirrel cage induction motor performance in terms of torque, power, efficiency, voltage and current can be analyzed for any rating.

Fractal dimension and fuzzy logic systems for broken rotor bar detection in induction motors at start-up and steady-state regimes

Squirrel-cage induction motors (SCIMs) are key machines in many industrial applications. In this regard, the monitoring of their operating condition aiming at avoiding damage and reducing economical losses has become a demanding task for industry. In the literature, several techniques and methodologies to detect faults that affect the integrity and performance of SCIMs have been proposed. However, they have only been focused on analyzing either the start-up transient or the steady-state operation regimes, two common operating scenarios in real practice. In this work, a novel methodology for broken rotor bar (BRB) detection in SCIMs during both start-up and steady-state operation regimes is proposed. It consists of two main steps. In the first one, the analysis of three-axis vibration signals using fractal dimension (FD) theory is carried out. Since different FD-based algorithms can give different results, three algorithms named Katz’ FD, Higuchi’s FD, and box dimension, are tested. In the second step, a fuzzy logic system for each regime is presented for automatic diagnosis. To validate the proposal, a motor with different damage levels has been tested: one with a partially BRB, a second with one fully BRB, and the third with two BRBs. The obtained results demonstrate the proposed effectiveness.

Effect of Power Deviations on Squirrel-Cage Induction Motors: Addressing the Impact of Voltage and Frequency Variations

This article discusses the effects of voltage and frequency variation on squirrel-cage induction motor performance. The major focus of the article is the impact of these elements on efficiency, thermal insulation life, starting characteristics, reliability, and cost penalties. Transient voltages are identified and harmonic distortion issues are also addressed; voltage/frequency issues associated with adjustable frequency drive applications, however, are beyond the scope of this article.

Diagnosis methods for stator winding faults in three-phase squirrel-cage induction motors

SUMMARY Induction motors condition monitoring is a very important process for immediate detection of the incipient faults. This prevents the spread of the faults up to risky degrees and avoids catastrophic stop of the motor and relevant production line. The stator winding fault is one of the most commonly occurring faults in alternating current machines. This paper is a comprehensive survey on the stator winding faults causes, diagnosis methods, indexes, and modeling and simulation methods. An efficient method is used to model and simulate the squirrel-cage induction motor performance under inter-turn fault. The results are used to obtain the performance of some common indexes of the fault and recognize the most proper index. Finally, some simulation results are compared with the corresponding experimental results and good agreements are achieved. Copyright © 2013 John Wiley & Sons, Ltd.

Analysis of Repairs on Three-Phase Squirrel-Cage Induction Motors Performance

This paper presents the results of research conducted to assess the effects of preventive maintenance and repairs on three-phase squirrel-cage induction motor performance regarding energy efficiency. The results brought interesting insights on how simple tasks can improve the energy efficiency, both in industry and in repair shop procedures.

Finite-Element Analysis of Field Distribution and Characteristic Performance of Squirrel-Cage Induction Motor With Broken Bars

This paper develops the foundations of a technique for diagnosis and characterization of effects of broken bars in squirrel-cage induction motors based on the time-stepping coupled finite-element approach. These studies are performed by using the model to compute healthy case, one-broken-bar fault, and two adjacent broken bars fault performance data, which contains stator starting current waveforms, the current density on the bars, the magnetic force distribution on the rotor bars, and the distribution of magnetic field. Meanwhile, the iron core loss distributions on the rotor tooth adjacent to broken bars are computed, and the harmonic component of air-gap flux density is analyzed. From this data, the faulty signatures are extracted. Theoretical approach together with experimental results derived from a two-pole 1.1 kW induction motor confirms the validity of the proposed method. Furthermore, this method, which could help to develop diagnostics of broken bars and performance evaluation of induction motors, has great potential in future applications

Lightly Ferromagnetic Rotor Bars for Three-Phase Squirrel-Cage Induction Machines

The concept of lightly ferromagnetic rotor bars to improve the starting performance of squirrel-cage induction motors is presented in this paper. Although the induction machines are popular for their ruggedness and simplicity, their starting torque is low and the starting current is 5-8 times higher than the rated current. A simple solution to this problem is the introduction of new rotor-bar material with lightly ferromagnetic properties, which in turn improves the starting power factor due to enhanced skin effect. Relevant electromagnetic theory supporting this is e presented in this paper. A computer simulation also produced expected results. A 1-hp induction machine has been tested to verify the proposed methodology.

Three-Phase Induction Generators: A Discussion on Performance

Three-phase Induction Generators (IGs) are increasingly being used as smallscale energy producing devices in nonconventional energy conversion systems. Both squirrel-cage and wound rotor types of induction motors used as generators are popular in this regard. The aim of this paper is to discuss critically the important contributions of researchers on the applications in both grid-connected and isolated modes of operations and critical evaluation of performance of these generators under different operating conditions. The major focus has been on the evaluation performance of squirrel-cage induction motor used as Self-Excited Induction Generator (SEIG), and both experimental and theoretical results are provided to represent the important characteristics of this generator. Finally, the future trend of research in this field has been pointed out.

Analysis of electromagnetic and thermal fields for induction motors during starting

In order to improve the starting performance of squirrel-cage induction motors, the so-called skin effect becomes very serious, which causes a highly uneven distribution of rotor-bar currents. The corresponding conduction losses of the upper and lower portions of rotor bars create high thermal stress, which may damage the rotor bars, particularly at the junction of rotor bars and end-rings. Hence, it is important to predict the starting and operating characteristics of induction motors more accurately for the purpose of ensuring the reliability of motor operation. This paper employs a visual-aided finite-element method to analyze the electromagnetic and thermal fields of induction motors during starting. By using visual and interactive pre- and post-processing techniques, the analysis can be applied to squirrel-cage induction motors with any physical dimensions, material properties, and system parameters. The starting performance, including the distributions of magnetic flux density, current density, loss density and temperature rise, are presented dynamically by computer animation, which are convenient and powerful for the evaluation and design optimization of induction motors. The theoretical predictions are verified by direct comparison with experimental results. >

Nonlinear complex finite-element analysis of squirrel cage induction motor performance

The application of complex analysis and the finite-element method for predicting the performance of a three-phase squirrel cage induction motor under a sinusoidal voltage-forced operation is described. The field region is discretised by triangular elements and the Galerkin approach is employed to solve a nonlinear complex Maxwell equation. Core saturation and the induced rotor bar currents are considered in the analysis. The induced back voltage and inner impedance in the equivalent circuit are obtained, based on the obtained field solution. The stator current is then iterately determined by using the fixed phase voltage and the external and inner impedances. The stator current, torque and power factor were obtained as functions of the line voltage and the slip. An experiment using a 1 hp squirrel-cage motor operating at several line voltages supplied by a 20 kVA balanced three-phase transformer was tested to verify the calculated results.