Design of electrical machines

A proposed hybrid system based on diesel generator and solar photovoltaic (PV) as an effective option to power a small remote community have been presented in this work. Running diesel generator constantly due to epileptic electricity supply in a small remote community which is not connected to the grid system is very expensive and not eco-friendly. The main objective of this proposed system is optimal design of a solar PV powered supply system to produce green power and reduce or augment the use of continual diesel generator sets, resulting in reduced cost of operation and maintenance. Solar radiation data is firstly analyzed and proper sizing and specification of the PV system and battery bank was done. The cost, hourly solar radiation, temperature and other design considerations were used as input of the hybrid optimization model for electric renewable (HOMER) software to analyze the system. In addition, a comparative study was carried out considering two scenarios of the proposed model system. In the first scenario, the diesel generation, solar PV system was treated as autonomous (or standalone). In the second scenario, the proposed model system was connected to the grid system. It is found that electrifying the small remote community using the proposed hybrid system is very beneficial and competitive with other types of conventional sources due to the fact that it decreases both operating costs and pollutants emissions. Also, results from the HOMER software are realistic and give promising results for on-grid schemes.

The electric machines, both DC and AC, are inventions of the 19th century. Of course, as a consequence of new materials and technologies, they experienced many changes during the 20th century. It is remarkable that, even nowadays, in the beginning of the 21st century, most electric machines of medium and high power are based on the electromagnetic principle. This identity of functional principle allowed an identity (first of all, conceptual) regarding modeling of electric machinery. It is worth to mention the different approachements [1], [2], [3], [4] and different authors [6], [7], [8], [9] to mathematical models of electric machinery in dynamic running. The main feature of most mathematical models is the assumption that the ferromagnetic cores of the electric machines are linear/straight. In practice, this assumption although accepted for the macroscopic behavior of electric machines, often revealed that non-linearity of these cores has a relevant influence on what is going on in...

Shaded-pole induction motors are the most frequently used single-phase electric motors in low power applications. Their main advantages are reliability, robustness, low level of noise and vibration, relatively simple manufacturing technology and cost effectiveness. These motors are the driving units of choice in the applications where the variable speed and high starting torque are not of utmost importance, in spite of the fact that they are characterized by inferior efficiency, power factor and starting torque compared to their single-phase counterparts. They are equipped with auxiliary massive copper coils at the stator side, which makes them self-starting, and strongly influence the motor characteristics. This study deals with the numerical modeling and analysis of a shaded-pole induction motor with a C-shaped stator frame. The analysis was performed using 2D finite elementbased transient magnetic numerical modeling. The primary objective was to investigate the influence of the number and size of the auxiliary shaded coils on the output torque speed characteristic. We explored the possibility of reducing the amount of material used while preserving the crucial/nominal properties of the motor. Our results have important implications in manufacturing simplification, which may be important for the eco-design of small motors and actuators, including their recycling and/or reuse process.

This study was designed to proposed a multivariate model of monthly mean daily Photo synthetically active radiation (PAR) from the constant ratio of the global solar radiation for six selected tropical ecological zones between 4.40°N and 13.03°N of Nigeria (Port Harcourt, Enugu, Abeokuta, Ilorin, Bauchi and Sokoto). The measured global solar radiation data was obtained from the Archives of the Nigerian Meteorological Agency, Oshodi, Lagos, over a period of thirteen years (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2009)(2010)(2011)(2012). The estimation was based on a correlation between clearance index, PAR and extraterrestrial computed using generalized 45% and 40% of monthly mean daily data set of global solar radiation and extraterrestrial solar radiation respectively on horizontal surfaces. The performance of the models developed were tested for validation using mean bias error (MBE), root mean square error (RMSE), mean percentage error (MPE), Nash-Sutcliff equation (NSE), chi

Launch of electric vehicles have seen a substantial rise for the past few years in emerging economies like India. In countries like India, the growth and penetration of the electric vehicles in the Indian automotive industry specifically for the two-wheeler segments are driven by the demand surge where cost and motor metrics have a substantial deciding factor. e in-wheel hubmotor, which is the prime mover for the two wheelers, decides the comfort zone of the customer in various metrics such as efficiency, torque, speed range, charging, and hence the distance covered. is paper addresses the design formulation of achieving a high torque Permanent Magnet Synchronous Motor (PMSM) conventionally known as the hub-motor, explicitly for electric two-wheeler application. e hub-motor is aimed for the defined D and L (280 × 30 mm) of volumetric constraints to deliver the rated torque of 50 Nm at the spinning speed of 400 rpm. e hub-motor design is aimed for distance range of 108 km/charge, at the vehicle speed of 54 km/hr for the designed diametric and volumetric constraints. is will lead to a typical cost-effective e-vehicle system since the required distance range of 108 km is achievable at the defined rim size and geometry with an enhanced efficiency greater than 90%. e design is carried out by Finite Element Analysis (FEA) using the electromagnetic software MotorSolve. e results computed are analyzed and validated for the optimal loading conditions for the ambient temperature of 50 °C. e results confirm the effectiveness of the proposed design formulation and methodology for achieving the high power density hub-motors for satisfying the customer's comfort zone in establishing the performance metrics of the electromagnetic system.

In this paper, a rotating contactless power transfer system achieving 200W for space application is presented. Both transformer and electronics designs are presented. A proof-ofconcept prototype, making use of components with space grade equivalent has been build and tested.

1 Student, Dept. of Mechanical Engineering, KLSGIT College of Engineering, Belagavi, Karnataka, India 2Prof, Dept. of Mechanical Engineering, KLSGIT College of Engineering, Belagavi, Karnataka, India ---------------------------------------------------------------------***--------------------------------------------------------------------Abstract Rotors and bearings are widely used in all the different engineering fields. Rotor rotation mainly depends on the dynamic characteristics of the system. These dynamic characteristics are basically the force and stiffness. The stiffness considered is the torsional stiffness as the rotor is rotating. The results were obtained with the ansys. The model basically consists of a rotor on a shaft supported by bearing. The CAD model was designed on SOLID WOKS software.

In today's dynamic and distributed work environments, effective project management is critical for team productivity and collaboration. This study presents the design and implementation of a collaborative project management tool aimed at enhancing team efficiency, communication, and workflow coordination. The research explores existing project management solutions, identifies gaps, and proposes a system that integrates real-time collaboration, task tracking, resource management, and seamless communication features. Utilizing a user-centred design approach, the tool incorporates an intuitive interface, cloud-based accessibility, and automation to streamline project execution. The case study evaluation demonstrates that the proposed tool improves team engagement, reduces communication bottlenecks, and enhances overall project performance. Future recommendations include further AIdriven automation and advanced analytics for decision-making support in project management.

This study compares the accuracies of five predictive models for estimating solar radiation amongst other meteorological parameters in Southwest Nigeria. Twenty-one years of monthly averages of six measured meteorological parameters obtained from six stations in southwest Nigeria have been subjected to five mathematical models for prediction purposes. Solar radiation and sunshine hours have been modelled using the sum of two-Gaussians, the sum of two-Lorentzians, Fourier on four harmonics, sine wave and fourth-order polynomial functions. The fitting accuracies of these models were tested using performance indicators; mean bias error (MBE), root mean square error (RMSE), mean percentage error (MPE), standard error (SE) and the correlation coefficient (R). An evaluation of the models showed that the Gaussian and Lorentzian models are in good agreement with the observed data. However, the Fourier on the fourth harmonics model had the lowest MBE, RMSE and MPE, consequently highest correlation coefficient values, indicating high model accuracy. Thus, the Fourier model has the best correlation with the observed data and is recommended for estimating these variables in the selected locations.

This paper presents use of the simplified alternator for a load shedding test on a 2000 kVA, 600 V. A three-phase, four-wire alternator rated 2000 kVA, 1600 kW, 0.8 power factor, 600 V, 1800 rpm has been connected to a 1600 kW, 400 kvar inductive load. The stator neutral point is grounded. The internal impedance of the generator (Zg = 0.0036 + j*0.16 pu) represents the armature winding resistance Ra and direct axis transient reactance X'd. The total inertia constant of the generator and prime mover is H = 0.6 s, corresponding to J = 67.5 kg.m^2. Speed regulation is modeled with Simulink® blocks implementing a PI regulator. The machine is excited with a constant voltage. A three-phase breaker is used to switch out a 800 kW resistive load. The breaker is initially closed and it is opened at t = 0.2 s, resulting in a 50% load shedding. In this paper, the machine is initialized in order to start simulation in steady state and the machine dynamics with and without speed regulation ha...

36% of the electrical energy consumed in Turkey is used by asynchronous motors, which are widely used in the industry. When considering industrial electricity consumption, it is observed that the share of electric motors in consumption reaches around 70%. Considering the rapid depletion of fossil fuels, which have a significant share in the energy supply, and the environmental problems caused by these sources, the efficiency and savings potential of electric motors, which use energy so intensely, is important. In this study, according to the ISO 500 data of 2019, Kastamonu Particle Board Plant (Kastamonu Entegre Co), which ranks 46 th among the largest industrial establishments in Turkey, is used in Adana MDF Facility, B1 group 18.5 kW, B2 group 15 kW and F1 group the energy saving potentials provided by the 315 kW IE2 efficiency class motors in case they are upgraded to the IE3 class are calculated and payback periods are presented. According to this, the energy saving provided by the B1 group motor is 1923 kWh/Year (119 $/Year), and the payback period is 5,01 years. In the B2 group motor, the energy saving provided is 2340 kWh/Year (145 $/Year), and the payback period is 3,95 years. On the other hand, the energy savings achieved in the F1 group motor is 18815 kWh/Year (1167 $/Year), and the payback period is determined as 8,68 years.

In this work, meteoroloogical data for Awka (6.207° N, 7.068° E), Enugu (6.452° N, 7.510° E) and Owerri (5.485° N, 7.036° E) in south eastern Nigeria, for the period of 11 years (2000 – 2010) were used to derive Angstrom type regression equations used for estimation of global solar radiation incident on a horizontal surface in the cities studied. In other to evaluate the significance of the results, three statistical methods have been used for the purpose. The three error formulae are; Mean Bais Error (MBE), Mean Percentage Error (MPE) and Root Mean Square Error (RMSE). The results shows that sunshine based model can be used for estimating global solar radiation in south eastern Nigeria.

The paper discusses the distribution of the thermal field in the magnetic core of a mono-phase transformer aggregate including the main and the voltage-adding transformer. The main aim of the analysis is to locate the most overheating section of the magnetic system studied and to investigate this overheat in the different overloads. The experimental data are compared with the simulation ones and the resulting error is less than 5 %.

This paper presents a finite element (FE) analysis of combinations of electrical steels in the lamination core steps of a real 6.3 MVA single-phase distribution transformer. The magnetic core of this transformer has a cruciform cross-section with lamination core steps. Two electrical steels are combined in the lamination core steps of transformer: a convectional grain oriented electrical steel (M-5) and laser-scribed electrical steel (23ZDKH90). 3-D FE simulations are performed to calculate the core losses (no-load losses) without and with combinations of electrical steels. B-H curves and iron loss curves of electrical steels are taken into account in the numerical simulations. The core loss calculated in FE simulation without combination of steels is compared with the core loss measured in no-load laboratory tests. Results obtained in this paper show that the combination of electrical steels in the lamination core steps can reduce 5% the core losses in single-phase distribution tra...

In this study, the optimum design of a brushless DC (BLDC) motor which is used for in-wheel light electric vehicle (LEV) propulsion is presented. The optimization work is mainly based on different slot-pole numbers which give a substantial performance improvement for that certain application. An outer rotor, 2.5kW, 150V BLDC motor which is widely implemented in light electric vehicle traction is selected. Finite Element Analysis (FEA) of the target motor design is conducted for various slot-pole combinations. By using the captured design data, the optimized motor is manufactured and tested. The test and simulation results are compared with each other to investigate the optimization approach.

Problems of application of instantaneous power theory theses to the analysis of electromagnetic and energy processes in nonlinear ferromagnetic circuits at different degrees of its saturation have been considered. Results confirm the necessity to revise the conventional methods and approaches to analyze the nonlinear circuits in saturation conditions. Streszczenie. Rozważono problemy związane z teorią mocy chwilowej zastosowaną do analizy elektromagnetycznych i energetycznych procesów w nieliniowych obwodach ferromagnetycznych w różnym stopniu nasyconych. Wyniki analiz potwierdzają konieczność rewizji metod konwencjonalnych i podejść do analizy obwodów nieliniowych w stanie nasycenia. (Badania procesów energetycznych w obwodach zawierających żelazo w warunkach nasycenia)

A semi-analytical framework is presented for the analysis of Synchronous Reluctance Motors. The model is based on a recently refined definition of the Harmonic Modeling Technique for electromagnetic actuators in polar coordinates, and includes the magnetic field solution in the soft-magnetic motor parts. In order to implement the model, a polar representation of the motor geometry is required. Therefore, a method to define the polar geometry representation is proposed and applied to model a benchmark motor topology. The calculation results of the benchmark motor are then validated against FEA predictions acquired for the actual geometry of the motor. This comparison shows that a good agreement is obtained.

High Speed PM Motors are popularly used in Spacecraft flywheel application. So, this paper proposes two different designs: one for classical sizing and the other for genetic one at 50 kW output power with 250 m/s tip speed. These two design trials of High Speed Permanent Magnet Synchronous Motors (HSPMSMs) are simulated with MATLAB, and Genetic Algorithm Toolbox. Then, the two design examples comparisons are introduced in analytical forms with study of machines waveforms, Total Harmonic Distortion (THD) and rotor losses. Finally, the effect of poles number on some sizing parameters and motor characteristics are illustrated in the form of charts with the waveforms. This is done at constant number of slots and phases with number of poles are 4, 6, and 12 at 50 kW output power and tip speeds of 250, 200, 150, and 100m/s.

This paper presents electromagnetic analysis of two permanent magnet transverse flux outer rotor machines with and without magnetic shunts. The research started with designing and analysing a permanent magnet transverse flux machine with inner rotor, previously patented by J. Giearas in 2010. However, the results obtained from the prototype test differed significantly from the estimated results. Applying 3D Finite Element Method tool main problem of the machine was detected. The problem was in high flux leakage which weakened magnetic flux density in the stator poles. Such observation led to designing two machines with outer rotor; with and without magnetic shunts. The role of the magnetic shunts is to minimize flux leakage in the stator in order to improve the performance of the machine. Electromechanical parameters of both outer rotor machines, with and without magnetic shunts, are compared in the paper. 3D Finite Element Method results are supported by laboratory analysis of the machines' prototypes. Experimental measurements proved that the machine with magnetic shunts demonstrated better performance comparing to the machine without magnetic shunts. Presence of the magnetic shunts in the machine resulted in reducing of flux leakage and cogging torque.

One of the disadvantages of permanent magnet (PM) transverse flux machines is high magnetic flux leakage in the stator and rotor cores. To improve the magnetic circuit of this class of machines, a generator with double coil was designed and built to research the problem. The machine topology is different from the topologies previously introduced in the literature. The main difference was in the stator and rotor configurations. The stator of the generator is divided by two parts: 1) outer and 2) inner. Two coils were placed in the inner and outer stators. The rotor with PMs was placed between the two stators. To diminish magnetic flux leakage in the stator and to decrease machine's weight, magnetic poles were placed in aluminum housings. This resulted in high-density eddy currents induced in the housings, and a significant raise of the temperature. The housing of the machine was modified. The prototype test showed that the modified version of the stator contributed to a significant decrease in temperature. Electromechanical parameters and cogging torque of the proposed generator is also studied and presented in this paper.

This paper presents electromagnetic analysis of two permanent magnet transverse flux outer rotor machines with and without magnetic shunts. The research started with designing and analysing a permanent magnet transverse flux machine with inner rotor, previously patented by J. Giearas in 2010. However, the results obtained from the prototype test differed significantly from the estimated results. Applying 3D Finite Element Method tool main problem of the machine was detected. The problem was in high flux leakage which weakened magnetic flux density in the stator poles. Such observation led to designing two machines with outer rotor; with and without magnetic shunts. The role of the magnetic shunts is to minimize flux leakage in the stator in order to improve the performance of the machine. Electromechanical parameters of both outer rotor machines, with and without magnetic shunts, are compared in the paper. 3D Finite Element Method results are supported by laboratory analysis of the machines' prototypes. Experimental measurements proved that the machine with magnetic shunts demonstrated better performance comparing to the machine without magnetic shunts. Presence of the magnetic shunts in the machine resulted in reducing of flux leakage and cogging torque.

A maioria dos motores síncronos utiliza um de dois métodos de sincronização. No primeiro método, a frequência da corrente de campo induzida no enrolamento do rotor é medida e utilizada para determinar quando aplicar a excitação ao campo principal. O segundo método considera a velocidade do rotor próxima à síncrona, então é aplicada a excitação sem levar em consideração a frequência da corrente de campo induzida. No primeiro método, quando o motor está próximo da velocidade síncrona, os controles tentam aplicar excitação conforme os pólos norte do rotor se aproximam dos pólos sul do estator (e vice-versa). Esta condição é detectada através da voltagem gerada pela corrente de campo induzida, descarregada através do FDR (resistor de descarga do campo). No segundo método, o motor síncrono pode chegar à velocidade nominal e, em seguida, a excitação é aplicada em um ângulo aleatório em relação aos ângulos do rotor e do estator. Nesse material, será abordado o primeiro método de sincronismo, utilizando o Sync-Rite Plus. 2-Comissionamento da roda de diodos e circuito de sincronismo Sync-Rite Plus. 2.1-Checagem das ligações e componentes Inicialmente, devem ser checadas todas as conexões da roda de diodos e do circuito de sincronismo, de acordo com o esquema de ligações. Uma roda de diodos típica é composta pelos seguintes componentes:

A semi-analytical framework is presented for the analysis of Synchronous Reluctance Motors. The model is based on a recently refined definition of the Harmonic Modeling Technique for electromagnetic actuators in polar coordinates, and includes the magnetic field solution in the soft-magnetic motor parts. In order to implement the model, a polar representation of the motor geometry is required. Therefore, a method to define the polar geometry representation is proposed and applied to model a benchmark motor topology. The calculation results of the benchmark motor are then validated against FEA predictions acquired for the actual geometry of the motor. This comparison shows that a good agreement is obtained.

Due to the trade-off between rotor mechanical strength and magnetic leakage, the high-speed capability of interior permanent magnet machines (IPMSM) is severely limited. This paper proposes a novel rotor topology capable of delivering 5 kW at 100,000 rpm using commercialized electrical steel laminations. By implementing the mechanical analysis in an iterative evolution process, two promising new topologies were developed. The first topology uses smooth compound curves (CC) to minimize the stress concentration and will be referred to as CCtype; the second topology is developed based on the CC-type with the aim to strengthen the structure further using the concept of a double-tied arch bridge (DAB) and referred as the DAB-type henceforward. After comparing the designs obtained from a detailed multiphysics optimization process, the DAB-type design was found to outperform the CC-type in all aspects, especially the mechanical robustness. This design was selected for experimental verification and a prototype was constructed. The mechanical and electromagnetic performances of the design were fully verified experimentally. The DAB-type prototype has achieved 2.31×10 5 rpm√kW, which is 1.5 times higher than other laminated rotor high-speed IPMSM designs found in the literature.

The paper analyzes the influence of the slots shape pertaining to induction motor armatures on the temperature development within its structure. The analysis of the temperature distribution within the studied motor was made using the Motor-CAD programming environment. The stated aim of the study was to emphasize the importance of choosing the geometrical shape of the slots of a classic rotating electric machine, still in the design phase, in order to obtain the validation - by thermal calculation - at the end of the design, of the geometrical structure that offers the highest technical and economic performance.

In this article; The step-by-step design of a 3-phase salient synchronous generator and efficiency optimization with particle swarm optimization technique are investigated. Unlike other studies in the literature, a system has been studied to minimize mathematical equation errors by using specific loading parameters that simplify the design process. It has been tried to obtain a program structure that minimizes programming problems by minimizing the number of variables used in the design. With the optimization of the specific loading parameters, the effects on the machine volume, cost and efficiency were examined. As a result, it has been observed that the productivity value increased with particle swarm optimization. In addition, the decrease in machine volume provided an advantage in terms of cost.

There are various types of batteries available in market among them lithium ion battery is most widely used battery in electric vehicle. The basic problem associated with it is about its charging time and temperature. Normally, to charge 48 V, 39 AH lithium ion battery 6-8 hours are required by normal 230V supply. The drawback of conventional method is more time is required for charging, more power, heat & switching loss. The conventional circuit available for battery charging has more cost. Our aim is to reduce this charging time and improve the battery performance as well as its life. The control circuit used in our charging kit is capable to charge the battery in minimum time interval at the same time it will reduce the power loss and improve the life of battery. This charging kit uses the closed loop approach, so drawbacks available in conventional charging method are overcome. In this closed loop scheme, temperature is taken as a feedback signal and according to that charging is done, so it improves life of battery because temperature is most affecting parameter on battery life.

This paper presents the cost reduction design of a brushless DC motor (BLDCM) considering twelve step control. The twelve step control can improve the output of the motor using the conventional six step control. Weight reduction can be effectively achieved by reducing rotor, stator and magnet through optimization of BLDCM using a response surface method (RSM). The BLDCM volume was decreased by about 45%, while satisfying basic performance requirements and improving efficiency. Original and optimized motors were built and tested. Experimental results are compared in terms of output power and efficiency.

This paper presents the cost reduction design of a brushless DC motor (BLDCM) considering twelve step control. The twelve step control can improve the output of the motor using the conventional six step control. Weight reduction can be effectively achieved by reducing rotor, stator and magnet through optimization of BLDCM using a response surface method (RSM). The BLDCM volume was decreased by about 45%, while satisfying basic performance requirements and improving efficiency. Original and optimized motors were built and tested. Experimental results are compared in terms of output power and efficiency.

In the domain of machines' design, one of the most important issues to solve is related with the controller's design, mainly, guaranteeing that the machine will behave as expected. In order to achieve a dependable controller, some steps can be considered, such as the formalization of its specification-before being translated to the program that will be inserted in the controller device-and the respective analysis and verification. Nowadays, some formal analysis techniques, such as formal verification, are used to achieve this purpose. The dependability of a controller, however, is impacted by its execution context. This paper proposes an approach for the formal verification of the specification of mechatronic system's controllers, which considers, on the formal verification tasks, the behavior of the plant and the behavior of the Human Machine Interface of the Mechatronic system. Some conclusions are extrapolated for other systems of the same kind.

In the applications of solar energy, the solar radiation data and their components in a region must be known for the design of a system. In the locations where no solar radiation data is available, this parameter can be determined by performing a reasonable correlation. In the study, the models of global solar radiation on the horizontal surface in the literature are investigated, and new empirical models based on the sunshine hour data for Erzincan, Turkey are developed. In order to indicate the performance of the models, the statistical test methods of mean bias error (MBE), root mean square error (RMSE) and mean relative error (MRE) are used. The results obtained indicate that the correlations developed in the study predict the global solar radiation reasonably well for the future projections.

This paper is committed to show a well-ordered system used to design a permanent magnet synchronous generator (PMSG). The fundamental focus of this work is the generators which are in gearless configuration, and in the fragmentary or couple of kilowatts power range. A straight lumped-component based model is introduced, which is utilized for fundamental investigation and design. Later, a proposed comprehensive design strategy-stated with conditions, tables, design limits and practical recommendations-are presented in full details. Likewise, a flowchart is created to be later used as a Matlab M-File code for PMSG design. The outlined strategies are then authenticated through three case studies while being compared to the result from Finite Element Method (FEM) of Maxwell package. The three case studies are firstly, comparing the effectiveness of the procedures with a PMSG presented in literature. Secondly compared to a generator from the market. And finally using the procedure to implement a 1 kw prototype generator and validate the results with it. Such comparisons have validated the proposed procedures as a contributed step-by-step simple and reliable design tool for such cluster of PMSGs. Keywords Finite element methods • Design methodology • Wind energy • Permanent magnet generators List of Symbols H m , H s , H g Flux intensity in magnet, steel, airgap (At/m) L m , L s , L g Mean length of magnet, steel, airgap (m) B m , B s , B g B tooth , , B core Flux density of magnet, steel, airgap, tooth, core (T) core Flux in core (Weber) 0 , m , s Permeability of air, magnet, steel (H/m) A m , A s , A g Area of magnet, steel, airgap (m 2) R outer , R inner Outer radius, inner radius (m) P, S, Q Number of poles, slots, phases f rated , n rated ,T rated , P rated , m_rated Rated: frequency, speed, torque, output power, radial speed (Hz, rpm, Nm, Watt, rad/s) SR o , SR i , RR o , RR i Stator outer, inner radius, rotor outer, inner radius (m) L stk , lg , lm , d c Length of stack, airgap width, magnet thickness, stator and rotor back iron (m) Ds, t s , s , bs0, bs1, bs2 Slot depth, teeth width, slot pitch, slot opening, slot upper, lower width (m) γ Coil span (in slots) N c , N s , ncpp, N tc , N a Number of Coils, series coils, coils per phase, turns per coil, effective number of turns V ,rated

This paper presents an analytical multi-physic modeling tool for the design optimization of a new kind of naval propulsion system. This innovative technology consists in an electrical permanent magnet motor that is integrated into a duct and surrounds a propeller. Compared with more conventional systems such as pods, the electrical machine and the propeller have the same diameter. Thus, their geometries, in addition to speed and torque, are closely related and a multidisciplinary design approach is relevant. Two disciplines are considered in this analytical model: electromagnetism and hydrodynamics. An example of systematic design for a typical application (a rim-driven thruster for a patrol boat) is then presented for a set of different design objectives (efficiency, mass, etc). The effects of each model are commented.

In the realm of residential, commercial, and agricultural applications, conventional pumps have long relied on induction motors. Nevertheless, a notable shift in the sectors like pump systems and electric vehicles where brushless DC (BLDC) motors are increasingly favored over the induction motor. The Bureau of Indian Standards (BIS) standards primarily revolve around key parameters are discharge (Q), head (H), and power input (Pi), intricately linked to the motor operating speed. In the pursuit of improving overall performance, especially in terms of efficiency, the focus is on enhancing both motor and pump efficiencies. Single-phase induction motors encounter limitations in their efficiency and speed capabilities. In contrast, BLDC motors offer a more versatile and efficient solution, the ability to modulate speed and optimized efficiency make them a superior choice for water pumping in agriculture applications. A BLDC motor with a 1 hp rating, designed to function within a voltage range of 72V and rotate at a speed of 3000 revolutions per minute (rpm), has been proposed as an efficient and effective option for these specific pumping needs. The design and analysis of this BLDC motor are carried out using finite element analysis software MagNet. Through finite element analysis using MagNet software, optimized BLDC motor designs with varying magnet thickness are developed and evaluated, resulting in significant improvements in water discharge capacity, pump head, and overall efficiency when compared to single-phase induction motor-driven pumps. Specifically, there is a 15% increase in both water discharge capacity and pump head. Furthermore, the overall conversion efficiency experiences a significant enhancement, ranging from 7% within the nominal operating head range.

Aos meus queridos pais Edgar e Clelis, pelo apoio incondicional, amor, carinho, dedicação e respeito viii ix "El futuro tiene muchos nombres. Para los débiles es lo inalcanzable. Para los temerosos, lo desconocido. Para los valientes es la oportunidad" Victor Hugo x xi Resumo O conhecimento dos valores dos parâmetros do modelo matemático dinâmico de geradores síncronos é de fundamental importância para a análise e controle de sistemas de energia elétrica. Os parâmetros elétricos do modelo matemático dinâmico do gerador síncrono, objetos deste trabalho, são as reatâncias síncronas de eixo d e q, as reatâncias transitórias e subtransitórias de eixos d e q e as constantes de tempo transitórias e subtransitórias de circuito aberto e de curto circuito de eixos d e q. Neste trabalho, apresentam-se metodologias de estimação dos parâmetros do modelo dinâmico de um gerador síncrono, no domínio do tempo e da frequência, usando métodos de otimização como o método de Levy, Gauss-Newton, Levenberg-Marquardt e o método Híbrido. Discute-se, particularmente, a metodologia de estimação dos parâmetros elétricos de um gerador síncrono de polos salientes, através dos dados obtidos dos ensaios de resposta em frequência com rotor em repouso. Os resultados foram obtidos em laboratório, usando um gerador síncrono de 2 kVA, 230 V, 1800 rpm, 60 Hz. Compararam-se estes resultados com os valores dos parâmetros obtidos em ensaios de curto circuito trifásico brusco e de rejeição de carga. Palavras-chave: geradores síncronos, estimação de parâmetros, métodos de otimização, ensaio de resposta em frequência.

The paper describes analytical approach solving the problem of dynamic analysis of two-dimensional fields of vibrational displacements and rotations caused by forces acting on stator of AC machine. Final set of three differential equations converted into algebraic ones is given and it is confronted with numeri-cal solutions obtained by finite element method.

This paper presents a new axial flux surface mounted permanent magnet (PM) field controlled TORUS type (FCT) machine. Machine structure and principles are explored and the field weakening feature of the topology as well as the advantages of the machine are presented in the first part. The second section introduces the linear model and sizing analysis using generalized sizing equations. Optimization of the machine pole number and power density maximization for the optimum pole number is also achieved. In the third section, 3D Finite Element Analyses (FEA) of the topology are illustrated for different field currents in order to accomplish the machine design and to determine the sizing of the optimum field winding. Furthermore, torque analysis of the FCT machine using 3D finite element analysis is also carried out and illustrated in the paper.

The single-phase induction motors (SPIMs) are widely used in several household and industrial applications and thus millions of them are produced every year. Despite the fact that their output power is low, their efficiency enhancement could lead to significant energy savings. The SPIMs are included to the new industrial efficiency standards for commercial motors. Consequently, the minimum efficiency that the SPIMs have to present is that of IE3 (premium-efficiency). The already conducted research efforts have not provided a robust and acceptable-from economical and manufacturing point of view-design procedure toward their efficiency improvement. For this purpose, a novel design methodology is proposed here. It is proven that the required efficiency ratings are achievable with the increment of the motor's axial length, the proper design of the rotor bar slot and the careful selection of the auxiliary to main winding turns ratio along with the value of the used capacitor. Aiming to verify its effectiveness, the presented methodology has been applied to SPIMs with different output power ratings. Moreover, the derived results are compared to the corresponding ones obtained from other design strategies. The motor's nominal performance and its behavior during the start-up phase have been determined through finite element analysis.

Most of the electrical machines design studies found in literature lie on the concept that the design under investigation (and optimization) focuses mainly on the geometrical aspects of the machine and thus takes into account only a certain ferromagnetic material (i.e. iron) for its parts. These studies, give little or no information about the influence of material alternatives on the same (and optimized) design. From a manufacturers' point of view though, this information is crucial especially nowadays that there are a lot of commercially available materials in the market. In this context, this paper presents the results of a research project in the design stage of an energy efficient three phase squirrel cage induction motor (SCIM), by investigating the effects of several soft magnetic materials (adopted for its stator and/or its rotor parts) on multiple quantities of primary concern such as: efficiency, power factor, output torque, losses, weight and cost. After a brief proposed design procedure, a total of twenty-two different materials from recent manufacturers' data were examined. Also, the main electromagnetic analysis was performed through commercial analysis software. Simple ranking methods are also proposed here for different application areas and the results obtained are then thoroughly discussed and commented.

Common high-torque low-speed motor drive schemes combine an induction motor coupled to the load by a mechanical subsystem which consists of gears, belt/pulleys or camshafts. Consequently, these setups present an inherent drawback regarding to maintenance needs, high costs and overall system deficiency. Thus, the replacement of such a conventional drive with a properly designed low speed permanent magnet synchronous motor (PMSM) directly coupled to the load, provides an attractive alternative. In this context, the paper deals with the design evaluation of a 5kW/50rpm radial flux PMSM with surface-mounted permanent magnets and inner rotor topology. Since the main goal is the minimization of the machine's total losses and therefore the maximization of its efficiency, the design is conducted by solving an optimization problem. For this purpose, the application of a new meta-heuristic optimization method called "Grey Wolf Optimizer" is studied. The effectiveness of the method in finding appropriate PMSM designs is then evaluated. The obtained results of the applied method reveal satisfactorily enhanced design solutions and performance when compared with those of other optimization techniques.

This paper presents a simple, practical, and effective design, analysis, and selection approach of a capacitor-run single phase induction motor as a manufacturing aid tool at the early stage of the design. The standard industrial motor frame sizes as well as the current design trends of larger lengths and smaller diameters-which are not likely presented in literature-are taken into account. At first, to verify the proposed approach, a sample single phase induction motor design is obtained regarding certain requirements, based mainly on the classic output coefficient concept. Then, numerous simulations over a large number of candidate motor topologies are conducted. This series of investigations is performed initially with respect to (1) certain operational industrial criteria, (2) the number of stator and rotor slots, and (3) the rotor cage material. After the relevant results are presented and commented, a selection strategy of an appropriate design is also proposed. Also, the effect of the running capacitor value is examined. It is seen that the total design and selection procedure are verified very satisfactorily. Finally, useful conclusions from a manufacturer's point of view are also extracted, dealing with important operational characteristics of the motor, such as power factor, winding currents phase shift, total losses, starting/rated torque ratio, efficiency, and other.

In this paper, the value of monthly average global solar radiation for Yola area has been estimated using different empirical models. The values of monthly average global solar radiation were calculated using the regression constants in the models (both linear and quadratic). The predictive efficiency was validated and compared based on mean percentage error (MPE), mean biased error (MBE) and root mean square error (RMSE). On comparison it was observed that the quadratic model is overall more accurate for calculating the Global Solar Radiation for Yola region, because of the fine agreement found between the estimated and the measured values and may be used reasonably well for estimating the solar radiation at a given location and possibly in elsewhere with similar climatic conditions.

The unavailability of the solar radiation measurements for different locations around the world leads to develop various empirical models to estimate the global solar radiation. In this consider, this study aims to investigate the performance of different solar radiation models to predict the monthly average daily global solar radiation on a horizontal surface. To achieve this, the measured global solar radiation data for a case study location are used. The model predictions are compared with the measured data to introduce the most accurate model for estimating the global solar radiation. The performance of each model is evaluated based on the different statistical indicators. The results show that the Robaa model has the best performance among the other models. Consequently, it can be used for estimating global solar radiation on a horizontal surface in the location under consideration. The accurate estimations of the global solar radiation using this approach can be used in the de...