Electrical Motors

The reliability and performance of a system with minimum life-cycle cost have become quite prominent in engineering systems. With increasing industrial applications, machines are operating in intricate conditions with higher uncertainty, causing greater vulnerability of system failure. This paper reports fault-related information of Brushless DC Motor (BLDC motor) in non-stationary operating conditions and presents several analyses to diagnose the faults. Fault diagnosis is the most crucial and important part of system prognostics which helps to increase the remaining useful life (RUL) and prevent catastrophic failures. Having both electrical and mechanical characteristics present in a BLDC motor, it shows several faults in different operating conditions. These faults cause a significant change in the vibration of the Motor. This paper deals with the anomaly detection of BLDC motor in non-stationary speed conditions using vibration signal analysis as well as extraction of several Condition Indicators (CI).

Currently, the feasibility to replace standard efficiency electric motors with higher efficiency ones is assessed with considerations differing from real operating conditions in the industry. This study compares the feasibility of replacing 26 standard efficiency motors (IE1) with high-efficiency efficiency ones (IE2 and IE3) in a sugar plant, based on three different energy scenarios and considering the incremental costs or depreciated costs of motors. Energy scenario 1 consider that motors operate for 6000 h/year at full load and nominal efficiency. While scenarios 2 and 3 consider the measured operating time and the load factor of motors. The results show that scenario 1 overestimates electricity consumption between 2 and 18 times, contrasted with a difference of 1e7% in scenarios 2 and 3, leading to saving potentials in scenario 1 between 1.2 and 33.4 times higher than for scenarios 2 and 3. Considering the incremental costs in scenario 1, it is feasibly to replace all the motor...

Starting from the first years of the proposed period right up to the 2000s, there were commercialization concerns of line start permanent magnet synchronous motors. This situation, which developed as a result of not developing methods to adequately explain the motor operating characteristics, and also because of the limitations associated with the non-high-performance manufacturing materials, took place widely until the 1970s. In subsequent years, the development of increasingly efficient materials, as well as the use of innovative methods, such as advanced magnetic circuit models and FEM analysis, which better reflect the performance of the motor, these motors became available for an increasing number of industries. In the past 10 years, research has paid off, and finally, line start permanent magnet synchronous motors have begun to be offered on the market as an alternative to AC induction motors. These motors, which are offered on the market with an IE4 efficiency class limits level that is currently tricky to achieve with traditional AC induction motors, are already included in the catalog of many major motor manufacturers.With this study, a detailed literature search was conducted and filtered on the development and improvement of line start permanent magnet synchronous motors. As a result of the study of numerous researches and more than 50 rotor topologies, design trends were identified that are important in the development of such motors. The development steps from the proposed years to the present have been discussed in terms of manufacturability, efficiency and performance.

This paper proposes a new design of a SPOKE type permanent magnet BLDC (Brush-Less Direct Current) motor by using pushing magnet. A numerical analysis is developed to calculate the maximum value of air-gap flux density. First, the analytical model of the SPOKE type motor was established, and Laplace equations of magnetic scalar potential and a series of boundary conditions were given. Then, the analytical expressions of magnet field strength and magnet flux density were obtained in the air gap produced by Ferrite permanent magnets. The developed analytical model was obtained by solving the magnetic scalar potential. Finally, the air-gap field distribution and BEMF (Back-Electro Motive Force) of spoke type machine was analyzed. The analysis works for internal rotor motor topologies, and either radial or parallel magnetized PMs (Permanent Magnets). This paper validates results of the analytical model by FEA (Finite-Element Analysis) as well as with the experimental analysis for SPOKE type BLDC motors.

— In the past year mini car has been increase in production, this type vehicle need low cost drive train and low maintenance. Motor Switched reluctance has many advantages this motor have lower manufacturing cost with low maintenance. In this paper Switched Reluctance Motor 6/4 is proposed based on sizing-motor procedure. Optimize process using design of experience (DoE) with manual iteration, the final motor design validate using using FEM method to calculate torque characteristic and thermal study. Simulation of switched reluctance motors using 2D finite element model, the result shows that the model established by the software Jmag using finite element method gives an overview characteristics of switched reluctance motors.

Most motors are designed to operate at a constant speed and provide a constant output; however, modern technology requires different speeds in many applications where electric motors are used. A variable speed drive (VSD) is a device that regulates the speed and rotational force, or output torque of mechanical equipment. Effects of applying VSDs are in both productivity improvements and energy savings in pumps, fans, compressors and other equipment. Variable speed drive technology and the importance of controlling the speed of existing motors have fascinated many attentions in the last years with the advent of new power devices and magnetic materials. This paper is a comprehensive review on applications of VSD in electrical motors energy savings. The aim is to identify energy saving opportunities and incorporated costs of applying variable speed drives to the existing applications of electrical motors. Subsequently, economic analysis, payback period and the effect of current and voltage harmonics generated by VSDs are presented. Authors are hopeful to provide useful information for future variable speed drive applications like fans, pumps, chillers, ventilators and heaters

http://www.sciencedirect.com/science/article/pii/S1364032111004308

Selection of electric motors and designing of efficient motor drives are important issues in the manufacturing of electric vehicle's traction system, especially with the highly competitive electric vehicles' market. Many electric motors can be used to drive electric vehicles, but the induction motor (IM) and the interior permanent magnet synchronous motor (IPMSM) are the dominant ones. This paper introduces a dynamic comparative analysis of the IM and the IPMSM in electric vehicles applications. To conduct this analysis, two identical IM and IPMSM have been selected and two motor drives have been built using field oriented control (FOC) techniques in Simulink software. The motors were used to drive identical vehicle body models with a fuzzy logic controller used to control the vehicle's speed. Both motors were compared mainly in terms of the speed and the torque responses with and without vehicle body load. The results showed a convergent performance between both systems; however, the IM-driven vehicle model has a little faster response compared to the IPMSM-driven one, whereas the latter has a higher torque ripple compared to the IM drive.

This thesis is concerned with the design and analysis of Switched Reluctance Motor (SRM) and its improved structure Double Stator Switched Reluctance Motor (DSSRM). Three configurations of SRM viz. Inner Stator, Outer stator and Double Stator are designed and simulated in ANSYS Maxwell Suite. Design parameters are chosen by aiming optimum performance of motor after literature review and analytical study of the motor. SRM is not a line start machine, so power converter circuit is required to excite the motor. Without proper switching of current, desired torque is not obtained in SRM. The converter circuit and switching unit is built in Maxwell Circuit Editor Tools. Both magnetostatics and transient analysis is performed to investigate motion torque, torque ripple, normal force and radial force. A good comprehensive comparison of three different types of SRMs based on their torque profile and force densities is presented. Simulation performed verified better performance of DSSRM.

This paper studies electromagnetic and parametric
design and performance analysis of an in-wheel out-runner
BLDC (Brushless Direct Current) electric motor designed
specifically for automotive applications. Typical design
techniques and simulation studies are applied to the BLDC
motor. Specifically, design specifications such as the number of
turns, winding area, and stator pole height composing the stator structure are obtained and the performance characteristics of the motor are investigated using the finite element method (FEM). Also, the outputs in terms of phase inductances, flux linkages of each stator winding and static torques for different rotor positions are calculated and evaluated. Finally, a dynamical performance analysis is performed using a physical electromechanical model the BLDC motor.

My Primary Posting for the field experience of the Nigerian Graduate Skills Development Programme (NGSDP) of the National Power Training Institute of Nigeria (NAPTIN) was at Egbin Power Plant Plc, located in Ijede, Ikorodu of Lagos State. On resumption of training in the plant on 18th December, 2013,  I was posted to the various departments in the plant including: Health Safety & Environment (HSE), Operations, Efficiency, Pump & Compressor, Turbine, Electrical 1 (PC&M), Electrical II and Instrumentation & Control Departments.  This Technical report gives an account of the major works I partook in during my stay in the plant focusing on my experience in three departments as well as the major jobs during the inter-sub-sectorial posting. Chapter one of the report gives an overview of Egbin power plant while chapter two, three and four dwells on the major works in Electrical 1, Electrical II and Instrumentation & Control Departments of Egbin Power respectively. Chapter five of the report covers my experience during the sub-sectorial posting with Lagos Transmission as well as Ikeja Distribution Company (IKEDC). Chapter six of the report gives a summary of my experience and the skills I have acquired over the period of the one year training.

In this paper the basic requirements and current developments of converter-fed drives for electric vehicles, particularly for electric cars, are reviewed and compared. The basic parts of the powertrain have been presented in the following sequence: electric traction motors, power electronic converters and traction control methods. Possible future developments of this components are discussed and summarized.

The losses in European Union distribution transformers are estimated at about 33 TW · h/year, whereas reactive power and harmonic losses add a further 5 TW · h/year. The reduction of distribution transformer no-load loss is particularly important as the ratio of no-load to load losses is nearly three. In this paper, the no load operation of wound-core transformers under sinusoidal and distorted supply-voltage conditions is investigated. For that purpose, a 2-D nonlinear transient finite-element analysis taking into account hysteresis has been developed. The hysteresis model is based on a modified Jiles–Atherton representation, and the proposed analysis is compared to experimental data.

In this paper the switching angles, from that the time required, to generate triggering pulses for IGBT switches of a single-phase Modified 11-Level Cascade H-Bridge Multilevel inverter is described by using Equal Phase (EP),Half Equal Phase (HEP), Half Height (HH) and Feed Forward (FF) methods. The proposed eleven level inverter is based on the H-bridge inverter. Instead of twenty IGBT switches as in conventional Cascade H-Bridge, this inverter requires only nine IGBT switches to obtain eleven level output. Because the numbers of switches are less, the cost and the complexity of the circuit is simple. The simulation results are presented using MATLAB/SIMULINK.

Brushless DC motor, also referred to as BLDC motor, has been a widely used electric machine due to its excellent performance over conventional DC motors. Due to complex operating conditions and overloading, several irregularities can take place in a motor. Stator related faults are among the most commonly occurring faults in BLDC motor. With an initial raise in local heating, a fault in the stator can largely reduce motor efficiency and account for the entire system breakdown. In this study, we present a deep learning-based approach to estimate the remaining useful life (RUL) of BLDC motor affected by different stator related faults. To analyze the motor health degradation, we have investigated two types of stator faults namely inter-turn fault (ITF) and winding short-circuit fault (WSC). A generator was coupled with the motor and using an average value rectifier (AVR), generator's output voltage was monitored for the entire lifecycle. A proven neural network for effective sequence modeling, recurrent neural network (RNN) is selected to train the voltage degradation data. For a better estimation of nonlinear trends, long-short term memory (LSTM) with attention mechanism is chosen to make predictions of the motor RUL for both types of faults. The main concern that encourages authors of this paper is the proposed method can be used for the real-time condition monitoring and health state estimation of BLDC motors. Also, the proposed AVR-LSTM method is not affected by environmental influences, making it suitable for diverse operating conditions. INDEX TERMS Attention mechanism, BLDC motor, remaining useful life, LSTM, stator fault.

Line start permanent magnet synchronous motors (LS-PMSM) are preferred more and more in industrial applications, because they can start on their own and because of their high efficiency. In this study, a new LS-PMSM rotor typology is suggested, which is modelled using surface mount permanent magnets, in which two different slot types have been used together. The rotor of an asynchronous motor on the industrial market in the IE2 efficiency segment has been remodeled in the study, resulting in an increase in motor efficiency from 85% to 91.8%. A finite elements software was used for determining motor design and performance, in addition to analytical methods.

A strategy for adaptive control and energetic optimization of aerobic fermentors was implemented, with both air flow and agitation speed as manipulated variables. This strategy is separable in its components: control, optimization, estimation. We optimized parameter’s estimation (from the usual KLa correlation) using sinusoidal excitation of air flow and agitation speed. We have implemented parameter’s estimation trough recursive least squares algorithm with forgetting factor. We carried separate essays on control, optimization and estimation algorithms. We carried our essays using an original computational simulation environment, with noise and delay generating facilities for data sampling and filtering.

Our results show the convergence and robustness of the estimation algorithm used, improved with use of both forgetting factor and KLa dead-band facilities. Control algorithm used in our work compares favorably with PID using the integrated area criteria for deviation between oxygen molarity and critical molarity (set point). Optimization algorithm clearly reduces energetic consumption, respecting critical molarity. Integration of control, optimization and adaptive algorithms was implemented, but future work is needed for stability. Methods were defined and implemented for stability improvement. We have implemented data acquisition and computer manipulation of air flow and agitation speed for actual fermentors.

The dynamic characteristics such as speed and torque as well as voltages and currents of PWM brushless DC motor inverter are analyzed with a MATLAB model. The contribution of external load torque and friction torque is monitored. The switching function technique is adopted for the current control of the embedded three-phase inverter that drives the brushless DC motor. In switching functions, power conversion circuits can be modeled according to their functions rather than circuit topologies. Therefore, it can simplify the overall power conversion functions. The trapezoidal type (back EMF) is used in the model as it has lower switching loss compared with sinusoidal type (back EMF). Results show reliable time analysis of speed, torque, phase and line voltages and currents. The effect of current commutation is clearly observed.

Three small unmanned aerial vehicles (UAVs) fly at Edwards Air Force Base, CA., Aug. 21, 2019. Most small UAVs are battery powered. To extend range and endurance, UAVs are now using hydrogen fuel cell technologies. (US Air Force photo, Staff Sgt. Rachel Simones) The modern weapons of war are thirsty for electrical power. Hybrid engines and all-electric motors promise to be the future of commercial and military systems, but due to cost of replacing entire fleets of vehicles, and the reliability of petrol and diesel engines, most military forces will be tied to internal combustion technology for many years. Small Unmanned Aerial Vehicles (UAVs), however, offer an exception. These weapons are playing an increasingly critical role in combat operations and are mostly powered by batteries. For these systems, staying in the air and operating for hours, rather than minutes, can be the difference between mission success or failure. Extending the flight time of small UAVs, therefore, is becoming a priority. There are two primary means of providing electrical power for small UAVs: batteries that store electrical energy or fuel cells that generate electrical power.

This work aimed to develop a parameterized, two-dimensional field model of a switched reluctance motor (SRM). The main task of the developed model was to calculate the value of the electromagnetic torque for various positions of the rotor. Based on these calculations, the characteristics of the electromagnetic torque were determined depending on the position of the rotor angle φ for the current function I (T = f (φ, I)). Using the model, it was possible to additionally observe the phenomena occurring in the motor winding, e.g., distributions, isolines of magnetic potential, induction, and to calculate the values of the temperature. The parameterized structural elements that made up the entire model can be freely changed and, thus, the results for various structures can be obtained. Thanks to this, it was possible to evaluate and compare motor of different designs. To validate the model, measurements were conducted on real-scale reluctance motors, and families of electromagnetic torq...

This paper presents a rapid sizing method for electrical machines estimating the length, rotor and stator diameter using only the maximum torque, the maximum speed, the maximum power and efficiency as input parameters. The method allows the calculation of separately excited synchronous (SSM), asynchronous (ASM) and permanent synchronous machines (PSM). To calculate the missing parameters needed for the estimation, a pre-compiled database of motors is considered. These parameters can be calculated using statistical interpolation methods. The proposed method combines these statistically calculated parameters with physical relations. Advantages of this method include the possibility to estimate the volume of the electrical motor as well as to use the interpolated data to scale the dimensions of the engine, which enables integrating the motor in a constrained space. To prove the validity of the method, different motors not present in the interpolated database are redesigned with the proposed method. This comparison shows that the model can display a divergence in a range of-6% to +10% in the estimation, which depends on the type of motor. This is small enough to be applied in the automatized design method of automotive transmission. The computational time of 1-2 s per motor design proves that the algorithm operates fast enough. 

Αντικείμενο της εργασίας είναι η παρουσίαση των δυνατοτήτων των σύγχρονων μη επανδρωμένων αεροσκαφών μάχης (ΜΕΑΜ), στο σύγχρονο πεδίο μάχης. Μετά από μία σύντομη ιστορική αναδρομή, γίνεται λεπτομερής ανάλυση για τα συστήματα προώθησης και τροφοδοσίας σε ηλεκτροκίνητο αεροσκάφος. Αμέσως μετά, δίνεται έμφαση στα μοντέλα προσβολής στόχου με μη κατευθυνόμενο βλήμα, που δύναται να φέρει ένα τέτοιο σύστημα. Με το πέρας της θεωρητικής προσέγγισης, ακολουθεί παραμετρική μελέτη για την ανάπτυξη ενός μοντέλου να εκπληρώσει αποστολές σε επίπεδο μονάδος και κάτω. Τέλος γίνεται σύγκριση με άλλα παρόμοια συστήματα, για την επιλογή του κατάλληλου, ανά περίπτωση.

This article introduces an on-line fault diagnosis (FD) system to detect and recognize open-phase faults in switched reluctance motors (SRMs). Both tasks, detection and recognition, are based on functions built with the same information but from different sources. Specifically, these functions are constructed from bus current measurement provided by a sensor and from the estimate of such a current provided by an extended Kalman filter (EKF) that performs the estimation from only rotor angular position measurements. In short, the FD system only requires two measurements for employment: bus current and angular position. In order to show its efficacy, results from numerical simulations (performed in a virtual test bench) are presented. Specifically, these simulations involve the dynamics of the SRM, including the magnetic phenomena caused by the analyzed faults. The motor dynamics were obtained with finite element simulations, which guarantee results close to the actual ones.

This paper concerns the thermal investigation of a surface-mounted permanent-magnet synchronous motor designed for high-temperature aerospace actuation applications. A finite-element package was developed, enabling accurate 3-D transient thermal analysis by considering complex and unsymmetrical actuator housing configurations. Its validity was verified by measurements carried out at different duty cycles and operating conditions.

This paper deals with the torque control of polyphase segment surface-mounted-permanent-magnet synchronous machines. First, we introduce a Lagrangian formulation for computing the optimal sinusoidal currents allowing to develop a given torque, both in normal operation mode and in fault operation mode (loss of one phase). Then, we present a torque control architecture allowing to switch from normal to fault operation mode with a minimum reconfiguration of the controller. All the theoretical results are validated by simulation and experiments on a test bench.

This article proposed a detection scheme for three-phase Line start
permanent magnet synchronous motor (LSPMSM) under different levels of static
eccentricity fault. Finite element method is used to simulate the healthy and faulty
LSPMSM with different percentages of static eccentricity. An accurate laboratory
test experiment is performed to evaluate the proposed index. Effects of loading
condition on LSPMSM are also investigated. The fault related signatures in the stator
current are identified and an effective index for LSPMSM is proposed. The simulation
and experimental results indicate that the low frequency components are an effective
index for detection of the static eccentricity in LSPMSM.

India produces around 24 million tons of corn every year. Product developed from corn needs to process it and peeling techniques used conventionally are not very efficient to avoid wastage of corn. The farmers are cultivating corn on small scale and it is difficult for them to peel it with advanced technology. With implementation of the technology in corn peeling we can reduce the wastage of corn which results in profit to the farmer. Authors have proposed the peeling machine of corn from point of view of small agriculture farms in India. The details of design calculation and CAD design of the machines is presented in this paper in detail. The design is validated and the results are found suitable to carry out the peeling of corn.

Topic: Superconductors and their real life applications as a theory of knowledge
Type: Essay
Subject: Physics
Academic Level: Undergraduate 1-2
Style: MLA
Language: English (U.S)
Number of Pages: 6 (double-spaced, Times New Roman, Font 12) Number of sources: 5
Made by https://writersperhour.com

Task Details:
1) Define superconductors;
2) Discuss their properties;
3) Describe how they can be utilized to solve various real life problems.

Hydrogen and oxygen generator is a clean energy equipment which produce H2 and O2 from water by electrolyzing water. Hydrogen is used as fuel and oxygen is used for combustion-supporting without additional gas cylinders. It can replace carbon-containing gases such as acetylene, natural gas and liquefied gas. It has the characteristics of safety, high efficiency, environmental protection and energy saving. AC 380V or 220V is rectified into direct current by high-efficiency IGBT inverter power supply, and applied to both ends of the electrolytic cell. The electrolyte (25% potassium hydroxide) in the electrolytic cell is subjected to direct current and electrochemical reaction occurs. The cathode produces hydrogen and the anode produces oxygen. The traditional welding ways include soldering,butt welding,oxyfuel gas welding. The investment cost of equipment is low,but there are some disadvantages of enameled copper wire soldering. Soft soldering Butt welding Oxyfuel gas welding with mechanical stripping, slow soldering speed, bad conductivity with mechanical stripping, be harmful to eye, poor welding connection flame diverge,which easy to burn other enameled wires. producing carbon monoxide when combustion. Oxyfuel gas is expensive,high welding cost. The oxyhydrogen torch produce high temperature, high energy and concentrated oxyhydrogen flame,which weld the joint of several enamel copper wires. The solder joints are strong and beautiful, no virtual soldering, no black smoke and exhaust gas.