Type Of Motor Research Articles

Combination of Implementation of Antiphase and Overcurrent Relays for Protection of 0.75 kW Three-Phase Induction Motor in Industry

Three-phase induction motors are the most widely used type of motor in industry. These motor operations are generally susceptible to unbalanced voltage disturbances. This interference is caused by the loss of one or two phases on the input side of the motor. This source voltage disturbance then causes an unbalanced current which flows to the coil, causing a phase shift, overheating the coil, and if left for a long time, it causes the motor to burn out. The research aims to design and implement a combination of antiphase relay (APR) and overcurrent relay (OCR) to prevent voltage drops due to failure of one or two phases and overcurrent to prevent overheating and fires in three-phase induction motor coils. Motor testing is carried out by adjusting the magnitude of the three-phase motor source voltage in three testing stages, i.e., tests A, B, and C, under no-fault conditions, 1-phase open and 2-phase open conditions respectively. The direct test results are then validated with ETAP simulations. In direct testing, A, B, and C can produce a current and relay working time of 6 A-31.04 s, 7.1 A-20.98 s, and 8.3 A-14.93, respectively. Meanwhile, testing using ETAP simulation can produce current and relay working times of 6A-31.366 s, 7A-20.599 s, and 8A-14.822 s respectively. The combination of an APR and an OCR can detect and interrupt voltage drops and overload currents in systems connected to 0.75 kW three-phase induction motors in the industry.

Impact of care coordination on service utilisation for children with medically complex cerebral palsy.

Complex care programmes for children with medically complex cerebral palsy (CP) exist; however, evidence for their impact is limited. This study (i) explored the impact of The Royal Children's Hospital Complex Care Hub (CCH) on hospital service utilisation rates over a 3-year period for children with medically complex CP compared with those eligible but received routine care, and (ii) compared health, disability and socio-demographic characteristics of children and their families in both groups. Electronic medical record data from 78 children (mean age 9.43 years, females n = 37) with medically complex CP who accessed CCH services, and 92 (mean age 10.86 years, females, n = 39) who received routine care were included. Multivariable regression was used to analyse service utilisation: number of emergency department (ED) presentations, length/number of inpatient and intensive care unit admissions and number/type of hospital appointments. Critical health-care needs, functioning/disability profile and child/family demographics for each group were compared. More children in the CCH group had a mixed motor type (73.1% vs. 15.2%), were classified within Gross Motor Function Classification System level V (76.9% vs. 34.8%), had respiratory, nutrition and social support needs and epilepsy. Children receiving CCH services had higher service utilisation rates; ED presentations (rate ratio (RR) = 1.81, 95% confidence interval (CI): 1.09-3.01), inpatient admissions (RR = 2.77, 95% CI: 2.01-3.83), outpatient encounters (RR = 1.69, 95% CI: 1.31-2.18) and telephone encounters (RR = 6.05, 95% CI: 4.56-8.02). Children with medically complex CP accessing a complex care service have higher service utilisation rates yet have more complex clinical presentations and higher support needs.

Research on Electromagnetic Performance and Rotor Eddy Current Loss Suppression of Ultra‐Low Temperature and High‐Speed Permanent Magnet Motor Materials for LNG Pumps

AbstractThere is no unified material selection principle for ultra‐low temperature and high‐speed permanent magnet motors used in liquefied natural gas (LNG) pumps, and high rotor eddy current losses can easily lead to vaporization of the transported LNG. This article first studies the electromagnetic performance of motor structural component materials at room temperature and ultra‐low temperature environments, and proposes the material selection principles for this type of motor. Based on the experimental measurement results of material electromagnetic performance, the loss characteristics of motors under ultra‐low temperature and room temperature environments were compared. Based on the mechanism of rotor eddy current loss and considering the influence of environmental temperature on the material properties of motors, three optimization methods for rotor eddy current loss are proposed. The impact of different suppression measures on rotor eddy current loss is revealed. The suppression of magnetic conduction harmonics can be achieved by opening stator auxiliary slots and optimizing their size and position. High conductivity metal shielding layers are used and their materials and sizes are optimized, And the use of magnetic slot wedges can simultaneously suppress three types of harmonics. Finally, the suppression principles of different optimization methods on rotor eddy current losses were analyzed, and the optimization effects and advantages and disadvantages of different methods were discussed, providing theoretical reference for the optimization design of high‐speed permanent magnet motors operating in ultra‐low temperature environments. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Comparison of Several Energy-Efficient Control Laws Using Energetic Macroscopic Representation for Electric Vehicles

Energy transition and decarbonization present significant challenges to transportation. Electric machines, such as motors and generators, are increasingly replacing internal combustion engines to reduce greenhouse gas emissions. This study focuses on enhancing the energy efficiency of electric machines used in vehicles, which are predominantly powered by batteries with limited energy capacity. By investigating various control strategies, the aim is to minimize energy losses and improve overall vehicle performance. This research examines two types of electric motors: Permanent Magnet Synchronous Motor (PMSM) and Induction Motor (IM). Real-time loss measurements were conducted during simulated driving cycles, including acceleration, constant speed, and braking phases, to mimic typical driving behavior. The simulation utilized characteristics from commercial vehicles, specifically the Renault Zoé and Bombardier eCommander, to assess the controls under different configurations. This study employed the Energetic Macroscopic Representation (EMR) formalism to standardize the analysis across different motors and controls. The results demonstrate significant loss reductions. The controls investigated in this study effectively reduce energy losses in electric motors, supporting their applicability in the automotive industry.

Effect of Voltage Supply Unbalance on Vibration of Three-Phase Induction Motor

Abstract The three-phase induction motor is the most popular electric motor used in industry. It has a simple and robust construction as well as a higher power density. It is a self-starting motor, therefore easier to start as compared to other types of electric motor. As the other benefit, a three-phase induction motor requires fewer maintenance measures. In order to maintain proper and continued operation, many parameters of a three-phase induction motor are constantly monitored. Among them is motor vibration. This is an important operation parameter frequently used to determine repair and maintenance needs to be taken on the motor. The vibration of a three-phase induction motor might be caused by mechanical as well as electrical problems. In this paper, the effect of magnitude unbalance of a three-phase voltage supply on the vibration of a three-phase induction motor is carefully investigated. To achieve this objective, two different laboratory experiments have been conducted. The first one is a three-phase induction motor supplied from a balance three-phase voltage supply. The second one is a three-phase induction motor supplied from an unbalance three-phase voltage supply. The unbalanced three-phase voltage supply condition is achieved by making the magnitude of one phase-voltage is 3%, 4%, and 5% lower than the magnitude of the other two phase-voltages. The vibration measurement is then taken in three different directions of the motor non-drive end (MNDE), i.e., horizontal (MNDEH), vertical (MNDEV), and axial (MNDEA). The experiment data show higher vibration in all directions, MNDEH, MNDEV, and MNDEA, as a load of the three-phase induction motor increases. Further, experiment data also show that higher vibration in all directions, MNDEH, MNDEV and MNDEA, is produced when unbalanced in magnitude voltage supply is higher

(Nd,Sm,La)-Fe-B-based hot-deformed magnets with excellent comprehensive properties for variable flux permanent magnet motors

An emerging motor type, the variable flux permanent magnet (VFPM) motor, has created a demand for permanent magnets with a new set of properties. These magnets must exhibit easily tunable magnetization, demanding for moderate coercivity values, low magnetizing fields, and first-order reversal curves (FORCs) with high flatness. In this work, we report that the doping of Sm and La in Nd-Fe-B-based hot-deformed magnet, followed by the Nd-Cu diffusion process, resulted in desirable magnetic properties, such as, a moderate coercivity (µ0Hc) of 0.55 T, a low magnetizing field (µ0Hmag) of 0.94 T and a high FORC flatness of 0.96, while maintaining a high remanence (µ0Mr) of 1.3 T. The FORC flatness achieved in this work is the highest and the comprehensive properties are superior to the previously reported Nd-Fe-B magnets for VFPM motors. Microscopic investigations revealed that the high flatness achieved in this hot-deformed magnet is attributed to the formation of Fe-lean thick intergranular phases realized by Nd-Cu grain boundary diffusion. The overall combination of the magnetic properties for the diffusion processed (Nd,Sm,La)-Fe-B magnet is excellent, in comparison with a commercially available Sm2Co17-type magnet, showing the promise of the former for use in VFPM motors.

A Grouping and Aggregation Modeling Method of Induction Motors for Transient Voltage Stability Analysis

Induction motors are the most common type of motor in power systems, constituting approximately 70–90% of the dynamic loads, making them significant contributors to system dynamics. In transient voltage stability analysis, dynamic equivalent models are commonly used to simplify the representation of a group of induction motors. This paper presents a method for the grouping and aggregation of induction motors at a common bus. Firstly, grouping rules are provided for clustering induction motors into several subgroups based on the mechanical principles of rotor force and motion, and aggregation rules are provided for aggregating a motor subgroup into a single-unit model based on the relationship between voltage drop and power transmission in distribution networks. Secondly, guided by the grouping rules, high-speed remaining electromagnetic torque and low-speed remaining electromagnetic torque are defined as new clustering indicators, and an adaptive K-means clustering method using silhouette coefficient verification is introduced to obtain the optimal motor subgroups. Thirdly, guided by the aggregation rules, a dynamic equivalent method is further introduced to obtain the equivalent single-unit model from a motor subgroup. Lastly, a transient voltage stability simulation in a typical distribution network is presented to illustrate that the proposed clustering and equivalent methods are more reasonable, accurate, and effective than traditional methods, as the obtained model has better dynamic characteristics and can more accurately reproduce the process of voltage collapse.

Solar photovoltaic fed synchronous reluctance motor with optimized rotor flux barriers: Design and performance optimization

This paper focuses on enhancing the design of a synchronous reluctance motor (SyRM) specifically tailored for solar photovoltaic (PV) water pumping applications. With growing adoption of green technologies and renewable energy sources, particularly solar power, there is a need to boost the motor's efficiency to meet the demands of such applications. Utilizing renewable energy for water pumping offers significant advantages in terms of sustainability, scalability, and environmentally friendly energy generation. Achieving optimal efficiency and reliability is paramount, as it reduces overall system cost and enhances reliability. SyRM design methodology in this study integrates both analytical and finite element (FE) procedures. Unlike other motor types, the rotor structure of the SyRM does not include any cages, magnets, or windings, resulting in a robust, reliable, and cost-effective manufacturing process. In SyRM, the rotor is constructed solely with barriers, which significantly impact torque shaping, torque ripple content, and power factor. This paper primarily examines the influence of various air-barrier shapes on different motor performance parameters, such as average torque, torque ripple, saturation, cross-section, and saliency ratio. The selected motor configuration for this investigation is a 4-pole, 100 Hz synchronous reluctance motor with 24 stator slots. The accuracy of the FE analysis findings is validated through a prototype of designed SyRM, followed by comprehensive performance evaluations conducted in a controlled laboratory environment. Additionally, this paper addresses an improved control strategy for a SyRM-based photovoltaic (PV) water pumping system. It eliminates the need for a speed controller in the position sensor-less field-oriented control (FOC) of SyRM. The solar water pump drive involves two stages of power conversion.

Morphological dictionary learning based sparse classification for small electric motor state recognition under unbalanced samples

Accurately recognizing sound states in the production line of small electric motors is of great importance for manufacturers to carry out quick repairs and ensure high quality deliveries. Since the number of normal samples is much larger than the number of abnormal samples in practice, resulting in unbalanced data, which poses huge challenges to traditional detection methods. To overcome these difficulties, this study presents a morphological dictionary learning-based sparse classification (MDL-SC) combined with audio data augmentation method for small electric motor state recognition under unbalanced samples. Firstly, audio data augmentation methods such as adding background noise, pitch shifting, time stretching and combined augmentation are investigated for augmenting the number and diversity of samples. Secondly, morphological dictionary learning is proposed for characterizing transient sounds of small electric motors and enhancing the discriminative feature learning capability of the dictionary. Finally, the minimum reconstruction error strategy is relied upon to establish automatic recognition of small electric motor states. Three small motor datasets with unbalanced ratios are established in the experiments to verify the effectiveness of the proposed MDL-SC, which has higher recognition accuracy under unbalanced conditions compared with traditional dictionary learning based sparse classification (DL-SC), k-nearest neighbors, support vector machines and convolutional neural networks. This study can provide some theoretical implications for the later development of online detection of small electric motors or other types of electric motors.

Noise-induced transport in a periodic square-well potential

We investigate a thermal ratchet based on a Brownian particle in a spatially periodic square-well potential driven by a time-dependent square-wave signal. In this model, we rock the Brownian particle between two square-well potentials tilted in opposite directions to induce a net current. Employing the Stratonovich formula and an independent approach using suitable boundary conditions and a normalization condition, we obtain an exact expression for the current in the adiabatic limit, and we observe that there are optimal values of various parameters at which the current can be maximized. In several parameter regimes, our simple non-linear model displays a behavior distinct from some other models of a rocked ratchet. For example, a reversal in the current direction is observed as the square-wave signal’s amplitude or the thermal bath’s temperature is varied. However, under similar conditions, no such current reversal was seen in the case of a periodically rocked Brownian motor in a sawtooth or a smooth potential. Furthermore, unlike the latter type of rocked Brownian motors, the square-well model yields zero current in the deterministic limit, as thermal energy is indispensable for the functioning of the motor.

Hip Displacement After Triradiate Closure in Ambulatory Cerebral Palsy: Who Needs Continued Surveillance?

Hip surveillance in cerebral palsy (CP) is an accepted practice with evidence-based guidelines implemented. For the skeletally immature with open triradiate cartilage (TRC), recommendations for radiographic surveillance stemmed from population-based studies. For nonambulatory CP, progression of hip displacement after skeletal maturity has been reported; less is known for ambulatory CP. We aimed to determine the prevalence and risk factors associated with progressive hip displacement after TRC closure, a proxy for skeletal maturity, for ambulatory CP. This is a retrospective cohort study of patients with ambulatory CP (Gross Motor Function Classification System I-III), with unilateral or bilateral involvement, hypertonic motor type, regular hip surveillance (≥3 radiographs after age 10 yr, 1 before TRC closure, ≥1 after age 16 yr), and 2-year follow-up post-TRC closure. The primary outcome was migration percentage (MP). Other variables included previous preventative/reconstructive surgery, topographic pattern, sex, scoliosis, epilepsy, and ventriculoperitoneal shunt. An "unsuccessful hip" was defined by MP ≥30%, MP progression ≥10%, and/or requiring reconstructive surgery after TRC closure. Statistical analyses included chi-square and multivariate Cox regression. Kaplan-Meier survivorship curves were also determined. Receiver operating characteristic analysis was used to determine the MP threshold for progression to an "unsuccessful hip" after TRC closure. Seventy-six patients (39.5% female) met the inclusion criteria, mean follow-up 4.7±2.1 years after TRC closure. Sixteen (21.1%) patients had an unsuccessful hip outcome. By chi-square analysis, diplegia (P=0.002) and epilepsy (P=0.04) were risk factors for an unsuccessful hip. By multivariate analysis, only first MP after TRC closure (P<0.001) was a significant risk factor for progression to an unsuccessful hip; MP ≥28% being the determined threshold (receiver operating characteristic curve analysis, area under curve: 0.845, P<0.02). The risk of MP progression after skeletal maturity is relatively high (21%), similar to nonambulatory CP. Annual hip surveillance radiographs after TRC closure should continue for Gross Motor Function Classification System I-III with an MP ≥28% after TRC closure, especially for bilateral CP and epilepsy. III.

Optogenetic control of kinesin-1, -2, -3 and dynein reveals their specific roles in vesicular transport

Each cargo in a cell employs a unique set of motor proteins for its transport. To dissect the roles of each type of motor, we developed optogenetic inhibitors of endogenous kinesin-1, -2, -3 and dynein motors and examined their effect on the transport of early endosomes, late endosomes, and lysosomes. While kinesin-1, -3, and dynein transport vesicles at all stages of endocytosis, kinesin-2 primarily drives late endosomes and lysosomes. Transient optogenetic inhibition of kinesin-1 or dynein causes both early and late endosomes to move more processively by relieving competition with opposing motors. Kinesin-2 and -3 support long-range transport, and optogenetic inhibition reduces the distances that their cargoes move. These results suggest that the directionality of transport is controlled through regulating kinesin-1 and dynein activity. On vesicles transported by several kinesin and dynein motors, modulating the activity of a single type of motor on the cargo is sufficient to direct motility.

Nutritional status of children with cerebral palsy in Ghana.

Limited knowledge on nutritional epidemiology in Ghanaian children with Cerebral Palsy (CP) necessitates a comprehensive investigation for an improved understanding of malnutrition in this population. We aimed to describe the epidemiology of malnutrition among children with CP in Ghana. The study used data collected as part of the Ghana CP Register (GCPR). The GCPR is an institution-based surveillance of children with CP aged < 18 years in Ghana. Between October 2018 and April 2020, N = 455 children with CP were registered. Data were collected on (i) weight, length or height, mid-upper-arm-circumference of children with CP; (ii) socio-demographic characteristics; (iii) motor type and topography, gross motor function classification system level (GMFCS); (iv) associated impairments; (v) educational and rehabilitation status for each child. Descriptive and bivariate analyses were performed. Mean and standard deviation age of the registered children at assessment was 5.9 ± 4.1 years, and 42.1% were female. Two-thirds of the children had ≥ one form of undernutrition (underweight or severely underweight: 38.9%, stunted or severely stunted: 51.2%, thin or severely thin: 23.8%). In the adjusted analysis, low maternal education, GMFCS-IV, speech impairment and epilepsy significantly increased the odds of undernutrition among participating children (aOR: 2.6 [95% CI:1.3-5.4]; 2.2 [95% CI:1.0-4.8]; 2.0 [95% CI:1.1-3.6]; 2.9 [95% CI:1.1-7.5] respectively). The high malnutrition rate indicates an urgent need for nutrition interventions and translational research to improve nutritional status and prevent adverse outcomes among children with CP in Ghana. Our study contributes important data and a framework to develop guidelines and evidence-based interventions for children with CP in Ghana.

Effects of air gap eccentricity on different rotor structures for PMSM in electric vehicles

In addition to research related to static eccentricity and dynamic eccentricity examining fault and diagnostic methods in various types of motors, there are also studies conducted for motors with non-uniform air gaps similar to the condition. In these studies, improvements and changes in motor performance for such types of motors can be observed. In this study, the effects of the rotor structures determined in the study and the air gap shape, which is effective by changing the eccentricity ratio, on the motor performance of the interior permanent magnet synchronous motor designed for electric vehicle applications are examined. Besides the elliptical rotor structure, which is widely researched in dynamic eccentricity studies, these eccentric motor structures also include novel rectangular and polygonal eccentric rotor structures. Motor models with non-uniform air gap structures are designed in two dimensions and subjected to simulation and analysis studies using the finite element method. At the end of the study, along with the parameters identified for motor performance, the harmonic components of the stator current, radial air gap flux density and the output torque obtained through Fast Fourier Transform analysis have been provided.

Overview of motors for heavy drones

The article is devoted to an overview of engines used in heavy drones. The main types of engines, their principles of operation, advantages and disadvantages are considered. The article examines a wide range of electric motors, such as brushless DC (collectorless) motors, which are the main components in modern quadcopters. Types of engines, their technical characteristics, as well as their use in specific models of quadcopters are also considered. This article will help you better understand the specifics of different types of motors and how they affect quadcopter functionality and performance.

Increasing efficiency of induction motor

In this work was analyzed induction motor, its advantages and disadvantages, and methods of modify it in way increasing its reliability and power coefficient. Power coefficient is the parameter which shows how much energy is used for yield and which just converting into heat. For analysis used calculation of induction motor which commonly used for developing serial asynchronous motor. Based on that calculation has modulated physical process which conducting in active parts of motor. For calculation of induction in armature and magnetic flux passes in it was used numerical mathematical model. This type of electric motors is common used so increase its efficiency and power characteristics is the one of way to reduce energy consuming. The developed way of modernization of induction motors, and analyzed reliability of it.

Numerical Simulation Method of Hydraulic Power Take-Off of Point-Absorbing Wave Energy Device Based on Simulink

Wave energy has a high energy density and strong predictability, presenting encouraging prospects for development. So far, there are dozens of different wave energy devices (WECs), but the mechanism that ultimately converts wave energy into electrical energy in these devices has always been the focus of research by scholars from various countries. The energy conversion mechanism in wave energy devices is called PTO (power take-off). According to different working principles, PTOs can be classified into the linear motor type, hydraulic type, and mechanical type. Hydraulic PTOs are characterized by their high efficiency, low cost, and simple installation. They are widely used in the energy conversion links of various wave energy devices. However, apart from experimental methods, there is currently almost no concise numerical method to predict and evaluate the power generation performance of hydraulic PTO. Therefore, based on the working principle of hydraulic PTO, this paper proposes a numerical method to simulate the performance of a hydraulic PTO using MATLAB(2018b) Simulink®. Using a point-absorption wave energy device as a carrier, a float hydraulic system power-generation numerical model is built. The method is validated by comparison with previous experimental results. The predicted power generation and conversion efficiency of the point-absorption wave energy device under different regular and irregular wave conditions are compared. Key factors affecting the power generation performance of the device were investigated, providing insight for the subsequent optimal design of the device, which is of great significance to the development and utilization of wave energy resources.

A Study on the Optimal Powder Metallurgy Process to Obtain Suitable Material Properties of Soft Magnetic Composite Materials for Electric Vehicles

This study systematically investigates the impact of the material properties of soft magnetic composites (SMCs) on the powder metallurgy forming process. It proposes a suitable material selection process for various motor types and shapes and determines the optimal forming conditions for each SMC material. This study employed the Taguchi design method to identify key control factors such as powder type, forming temperature, and forming speed, and analyzed their effects on relative density. Simulation results indicated that AncorLam HR exhibited superior properties compared with AncorLam and Fe-6.5wt.%Si. The optimal conditions determined through signal-to-noise ratio (SNR) calculations were AncorLam HR at 60 °C and five cycles per minute (CPMs). Validation through simulation and SEM analysis confirmed improved density uniformity and reduced defects in products formed under optimal conditions. Final prototype testing demonstrated that the selected conditions achieved the target density with minimal variance, enhancing the mechanical properties and performance of the motors. These results suggest that the appropriate application of SMC materials can significantly enhance motor efficiency and reliability.

Optimal Electric Motor Designs of Light Electric Vehicles: A Review

This paper summarizes the results of numerous studies aimed at improving the operating characteristics of electric motors used in light electric vehicles (LEVs). This review focuses on four types of electric motors that can be installed in the drive wheel rims of LEVs. Due to the availability of new magnetic materials and the use of advanced techniques for optimizing the design of electric motors, new motor topologies have emerged. The latest generation motors have been shown to be more efficient, have higher torque density, and generate less torque ripple. This paper indicates and discusses current trends in the topology of electric motors designed for LEV drives. In this context, the effectiveness of the proposed design modifications in terms of selected motor operational characteristics was assessed. The proposed new topologies were compared with commercial solutions, also in terms of the possibility of improving their operational parameters.

Maximum torque per ampere control of permanent magnet/reluctance hybrid rotor dual stator synchronous motor

AbstractCompared with a traditional low‐speed high‐torque permanent magnet synchronous motor (PMSM), a permanent magnet (PM)/reluctance hybrid rotor dual‐stator synchronous motor (PM/RHRDSSM) has the advantages of high torque density and high space utilization. This type of motor is composed of a "back‐to‐back" PM + reluctance hybrid rotor and an inner and outer double stator. The number of poles of the inner and outer unit motors is the same, and the inner and outer stator windings are connected in series, driven by a single inverter. Due to the special mechanical structure and electromagnetic relationship of PM/RHRDSSM, traditional PMSM and synchronous reluctance motor maximum torque per ampere (MTPA) control strategies are no longer applicable. In response to this issue, the authors establishe a PM/RHRDSSM mathematical model of stator winding series structure and propose a MTPA control strategy suitable for this new type of motor. This strategy is aimed at the special mathematical model of PM/RHRDSSM and derives the analytical expression of MTPA trajectory, which minimises the required stator current amplitude of PM/RHRDSSM at various load torques, thereby minimising the motor copper loss. Finally, the effectiveness and practicality of the proposed control strategy were verified through simulation and experiments.