COMPARATIVE ANALYSIS OF SIX PHASE INDUCTION MOTOR

The conventional method of a single phase induction motor windings design usually constructed the main and auxiliary windings in both slot. So, there was a complicated winding design if that compare to the three-phase induction motor. Because of that, this study was aimed to design a new windings design of a single phase induction motor that construction like a three-phase induction motor. This study was focused to design a 24 slot capacitor-start capacitor-run induction motor. The windings in the motor are divided in 3 group like a three-phase induction motor. The two windings act as a main windings and the other winding act as auxiliary winding. The current rating of the winding of the proposed single-phase induction motor was 2.74A. The performances of the proposed method were compared with the performances of a three-phase induction motor that had the same current rating. The motor used as a comparator was a three-phase induction of 380/220V, 2.74/4.7A, Y/Δ, cage rotor, 4 poles, 1.5 HP, 1400 RPM, 50Hz. The result of this study showed that the proposed design of single phase induction motor could be operated with better performances than the three-phase comparator induction motor’s.

Induction motor is the most motor applicable in the world. especially three phase induction motor. Furthermore 95% of induction motor are used as propulsion in industry. However, maintenance costs are large enough more than 50% of operating costs of the industry or the factory. To reduce these costs is to detect early faults in induction motors. One way to detect initial faults is to measure and analyze the temperature of the induction motor. In this research, the authors design temperature monitoring of a three-phase induction motor using the internet of things to make it easier for users to monitor the temperature of an existing three-phase induction motor and to schedule maintenance if temperature reach the operating limit. The field system elements consist of SoC ESP32 to collect data from 2D temperature, to drive lead screw and to send data to cloud. The SoC ESP 32 is connected to the AMG8833 temperature sensor array which collect the frame of temperature of a three-phase induction motor in the form of an 8x8 array. In addition, the SoC ESP32 is also connected to the motor driver L293D to regulate the movement of geared DC motor. Geared DC motor is used to drive the lead screw which already has a mount for placing the AMG8833. From the test on 18.5 kW, 360V induction motor installed in chemical industry, it is obtained the sensor can measure temperature accurately and it travel smoothly above frame. In the storage using MongoDB database, the data transmission fulfilled the QoS requirement.
 

There are several types of motors to choose from when selecting motors for large HP (2000 HP - 10.000 HP) cement plant applications including; squirrel cage induction motors, wound rotor induction motors, PAM induction motors, synchronous motors, and DC motors, all of which have their own advantages and disadvantages. This paper will compare the operational characteristics of the induction, synchronous and DC motors to demonstrate how to apply the different speed-torque-current characteristics of each when driving typical cement plant loads. This paper will compare several different starting methods for AC motors such as across the line starting, autotransformer, solid state starting, and Adjustable Speed Drive (ASD) and discuss the limiting factors of each method such as starting current requirements and cage heating. A comparison of the operating characteristics of induction and synchronous motors will demonstrate how the power factor and efficiency advantage of synchronous motors can be applied to lower the energy cost of a cement plant. The variable speed operation of induction and synchronous motors operating on adjustable speed drives will be compared with the operational characteristics of DC motors which vary speed without the use of a drive.

This paper introduces multiphase induction motor drives system under sensorless conditions, which is simulated and analyzed by utilizing its multiple control freedoms in the mode of high frequency signal injection. In this method, because nine phase induction motor have four orthogonal d-q planes compared to traditional three phase induction motor, so high harmonic plane can be used for other applications, for example, extracting rotor position based on high frequency injection signal technique. In the multiphase induction motor, inductance value is smaller in the high harmonic plane contrast to fundamental plane, in other words, it can get larger current signal amplitude under the same voltage amplitude, reducing the difficulty of the position signal extraction. changing rotor slot numbers will affect the air-gap length distribution, and it can be concluded that there is a saliency in the d 7 -q 7 plane through modulation of rotor slots. The module is simulated in the environment of simulink and ansoft.

Multiphase machines are a promising alternative for high-reliability applications. In these applications, overmodulation (OVM) is important since it allows attaining higher modulation indices by injecting, besides zero-sequence voltage harmonics, current-producing ones. In general, the existing techniques are able to limit to some extent the current total harmonic distortion (THD). However, most do not ensure the minimum current THD, thereby not guaranteeing the minimum harmonic stator copper loss. Furthermore, most are intended just for particular phase numbers <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$n$</tex-math></inline-formula> , symmetrical/asymmetrical winding arrangements and neutral-point (NP) configurations. OVM with low THD remains unaddressed in most types of multiphase motors. This paper overcomes these limitations by proposing a generalized OVM strategy that attains the minimum current THD in induction motors with any <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$n$</tex-math></inline-formula> , winding arrangement and NP configurations. Two techniques are outlined. One of them injects only non-torque-related harmonics, while the other technique exploits torque-producing harmonics to further reduce the current THD and to attain modulation indices up to square waveform. The superiority of the proposal in terms of current THD is substantiated through studies for multiple kinds of multiphase machines. The experiments are performed by using two six-phase induction motors with symmetrical/asymmetrical windings when 1 and 2 NPs are set.

This study is concerned with the implementation and analysis of the modified six phase induction motor (MSP-IM) that drives a centrifugal pump system. The MSP-IM aims to enhance the torque pulsation and increase the motor reliability. Dynamic models of six-phase IM are derived. A trial and error based tuning of PID controllers is employed to sustain the motor speed at the predefined reference values. A six-phase low pass filter is designed to eliminate the undesirable harmonics contents. A scalar V/f closed-loop six-phase induction motor control is employed and its simulation results are discussed. Pulse width modulation (PWM) based simulation studies were developed for MSP-IM using Matlab/Simulink Software. The results show that the PWM inverter reduces the THD for current and voltage waveforms. The performance of the MSF-IM is enhanced compared with the equivalent three phase IM.

Multi-phase induction motors feature a high fault-tolerance capability that makes them suitable for safety critical applications. On the other hand, concentrated winding is more fault-tolerant than conventional distributed winding. Therefore, the general idea is to use concentrated winding on the six-phase induction motor to gain more fault-tolerance capacity. Using concentrated winding has several advantages over distributed one, but it has the disadvantage of higher distortion of air gap flux density, which affects the motor performance significantly. In this paper, some concentrated windings are studied analytically by using the winding function analysis, and the layout with better performance is chosen to be compared with the conventional 2-pole distributed winding. With reference to the lamination of a 90W symmetrical six-phase induction motor, both calculation and simulation results show that the performance of the selected concentrated winding is not comparable with the distributed winding. Performance measurements from pervious works, are used for evaluation.

Three-phase induction motors are favored by contemporary manufacturers due to their cost-effectiveness, durability, and operational simplicity. Numerous studies aimed at enhancing the performance of this motor are ongoing, with the improvement in performance being commensurate with the additional expenses paid. Consequently, further initiatives are required to enhance the performance of three-phase induction motors without incurring substantial additional expenses. This study aims to enhance the performance of three-phase induction motors cost-effectively through the development of the stator coil design. The stator winding was designed with a 2-layer coil configuration, with each layer constituting its pole, resembling a 20-degree asymmetric six-phase coil design. The study’s results indicated a performance enhancement in the newly designed 3-phase induction motor, with output power and load torque increasing by 16.47% each. Our revolutionary design has the potential to improve the performance of other 3-phase induction motors without incurring significant additional costs.

Preface. Chapter 1: INTRODUCTION. 1.1 A Brief History of Electric Power Systems. 1.2 The Structure of the Power System. 1.3 Outline of the Text. Chapter 2: BASICS OF ELECTRIC ENERGY SYSTEM THEORY. 2.1 Introduction. 2.2 Concepts of Power in Alternating Current Systems. 2.3 Three-Phase Systems. 2.4 The Per Unit System. 2.5 Electromagnetism and Electromechanical Energy Conversion. 2.6 Permeability and Magnetic Field Intensity. 2.7 Flux Linkages, Induced Voltages, Inductance, and Energy. 2.8 Hysteresis Loop. 2.9 Eddy Current and Core Losses. 2.10 Energy Flow Approach. 2.11 Multiply Excited Systems. 2.12 Doubly Excited Systems. 2.13 Salient-Pole Machines. 2.14 Round or Smooth Air-Gap Machines. 2.15 Machine-Type Classification. 2.16 P-Pole Machines. 2.17 Power System Representation. Problems. Chapter 3: POWER GENERATION AND THE SYNCHRONOUS MACHINE. 3.1 Introduction. 3.2 The Synchronous Machine: Preliminaries. 3.3 Synchronous Machine Fields. 3.4 A Simple Equivalent Circuit. 3.5 Principal Steady-State Characteristics. 3.6 Power-Angle Characteristics and the Infinite Bus Concept. 3.7 Accounting for Saliency. 3.8 Salient-Pole Machine Power Angle Characteristics. Problems. Chapter 4: THE TRANSFORMER. 4.1 Introduction. 4.2 General Theory of Transformer Operation. 4.3 Transformer Connections. Problems. Chapter 5: ELECTRIC POWER TRANSMISSION. 5.1 Introduction. 5.2 Electric Transmission Line Parameters. 5.3 Line Inductance. 5.4 Line Capacitance. 5.5 Two-Port Networks. 5.6 Transmission Line Models. Problems. Chapter 6: INDUCTION AND FRACTIONAL HORSEPOWER MOTORS. 6.1 Introduction. 6.2 Three-Phase Induction Motors. 6.3 Torque Relations. 6.4 Classification of Induction Motors. 6.5 Rotating Magnetic Fields in Single-Phase Induction Motors. 6.6 Equivalent Circuits for Single-Phase Induction Motors. 6.7 Power and Torque Relations. 6.8 Starting Single-Phase Induction Motors. 6.9 Single-Phase Induction Motor Types. Problems. Chapter 7: FAULTS AND PROTECTION OF ELECTRIC ENERGY SYSTEMS. 7.1 Introduction. 7.2 Transients during a Balanced Fault. 7.3 The Method of Symmetrical Components. 7.4 Sequence Networks. 7.5 Line-to-Ground Fault. 7.6 Double Line-to-Ground Fault. 7.7 Line-to-Line Fault. 7.8 The Balanced Three-Phase Fault. 7.9 System Protection, An Introduction. 7.10 Protective Relays. 7.11 Transformer Protection. 7.12 Transmission Line Protection. 7.13 Impedance-Based Protection Principles. 7.14 Computer Relaying. Problems. Chapter 8: THE ENERGY CONTROL CENTER. 8.1 Introduction 8.2 Overview of EMS Functions. 8.3 Power Flow Control 8.4 Power Flow 8.5 Stability Considerations 8.6 Power System State Estimation 8.7 Power System Security 8.8 Contingency Analysis 8.9 Optimal Preventive and Corrective Actions 8.10 Dynamic Security Analysis Chapter 9: THE PRESENT AND FUTURE OF ELECTRIC ENERGY SYSTEMS. 9.1 Introduction. 9.2 Challenges Facing the System. 9.3 Blackouts and their Impact. 9.4 Mitigating and Coping. REFERENCES. INDEX.

In order to avoid lower efficiency, poor power factor and lower torque density, the airgap length of a three-phase squirrel cage induction motor (SCIM)should not be designed very large. On other hand, the distortion of airgap flux density distribution can be minimized by enlarging the airgap length. This has informed machine designers to choose very carefully the airgap length while designing a three-phase SCIM. This paper deals with the influence that the airgap length has on the performance of a three-phase SCIM having a capacitive auxiliary three-phase stator winding. The three-phase auxiliary winding is only magnetically coupled to the stator main winding. A conventional 5.5 kW, 50-Hz, and 4-pole three-phase SCIM is modified to accommodate both main and auxiliary windings in the same stator slots, while maintaining the rated power to 5.5 kW. The results obtained from practical measurements evidenced that for a large airgap it is possible to obtain high efficiency and good power factor with the presence of a capacitive auxiliary stator winding. The high efficiency is mainly due the decrease in iron and stator copper losses. The iron losses decrease with increase in airgap length for the SCIM with or without a capacitive auxiliary winding, while the stator copper loss is obtained by reactively exciting the three-phase auxiliary stator winding.

A comparative analysis of torque profiles of an AWSP-IM under various phase loss conditions with respect to the healthy six-phase condition is presented.The captured plots are accompanied by a magnified (zoom) in order to obtain a better sense of the consequences on the torque-ripple content in the resulting timedomain torque profile.The phase loss scenarios analyzed in this paper are based on the simulated result of an AWSP-IM modeled using MATLAB/SIMULINK platform.The analysis of ripple contents in the torque profiles under various phase loss conditions reflects the deterioration of the torque-profile quality in each case.Further its comparison with result of three phase counterpart shows that AWSP-IM exhibits better performance than the Three Phase Induction Motor (TPIM) under the phase loss without any external control techniques.Moreover, some of the cases gave results, which were very close to the healthy operation of TPIM.

In this paper, the transient and steady-state performances of an isolated self-excited induction generator driven by a wind turbine and feeding power to a dynamic load such as a three-phase induction motor are analyzed. Mathematical modeling and simulation study of the whole system, including the wind turbine, induction generator, capacitor, pulse width modulated voltage source inverter, and dynamic load, are carried out with closed-loop voltage and frequency controller. The complete system is modeled in the stationary $d-q$ frame and validated by comparing simulation and experimental results at no-load. The same mathematical model is then used to study the transient performance of the self-excited induction generator supplying to a dynamic load. When the induction motor is connected to the induction generator without any voltage and frequency controller, it causes severe transients in electrical and mechanical variables of the generator. Due to the large starting-current requirement of the induction motor, there is a collapse of the terminal voltage of the generator. A bidirectional pulse width modulated source inverter with DC link battery is connected with the generator and operated in closed-loop control mode to maintain voltage and frequency and to operate the induction motor successfully with variable wind speed and mechanical load.

A wind turbine with variable-voltage, variable-frequency electrical output was used to power resistive loads and induction motors in an autonomous system. The AC system was selected because AC motors, in multiple kilowatt sizes, can be more practical than DC motors. A wind turbine which produces electricity has a lower overall efficiency than a system producing mechanical power but offers more flexibility in adapting to varying loads and in locating the wind turbine near the load. A permanent magnet alternator designed to operate with a rotor speed from 70 to 150 r/min was first operated in the laboratory. The frequency of the output varied from 30 to 65 Hz, while the voltage changed from 85 to 218 V, resulting in voltage to frequency ratios (V/f) from 2.6 to 3.3 with various loads. The alternator, with a maximum rated output of 9 kW, provided power to resistive load or induction motor loads. The tests revealed that standard three-phase, 240 V, 60 Hz, AC induction motors will operate with an input of 85 V and 30 Hz. A motor temperature rise of 40° C above ambient was not exceeded when power was supplied by the alternator to a 7.6 kW motor. System efficiencies were nearly equivalent to those obtained with utility power, even though the V/f was below that calculated from the motor’s nameplate. The wind energy conversion system (WECS) was then operated in wind-speeds of 3.5 m/s or greater. This WECS was capable of providing power to satisfactorily operate induction motors in an autonomous system.

In this paper, an approach for reducing the torque ripple in a two phase unsymmetrical induction motor is analyzed. A single phase induction motor is basically a two phase induction motor and generally, the windings on the stator are not identical. Hence, it is called unsymmetrical two phase induction motor. If an unsymmetrical motor is supplied by two phase balanced supply voltages then the ripples in the electromagnetic torque are unavoidable. However, if the supply voltages are made unbalance to counter the unbalance in the windings the torque ripple can be reduced. The mathematical model of the machine in stator attached reference frame is used to derive the torque expression in terms of stator currents. The torque expression consists of a constant term and a pulsating term. These terms used together unable finding the conditions on stator currents and hence stator voltages so that the ripples in the torque produced can be mitigated.

This paper presents a discrete time algorithm able to identify all electrical parameters of three phase induction motors. This technique can be also applied to identification of other machines such as permanent magnet synchronous motor (PMSM), single-phase induction motors (SPIM), and others systems, that will be described opportunely. The identification algorithm is based on robust model reference adaptive controller (RMRAC) applied to electric machine model. The identification uses only measurements of stator currents with standstill rotor. From the correct parameters it is possible to design high performance controllers and sensorless drives for the induction motor. Furthermore, the correct parameters of induction motor allow a better representation of dynamic simulation behavior of machine. Experimental results are presented to provide the effectiveness of the method.