This paper aims to study the skewing of a servomotor for robot application. Skewing motor helps to reduce torque oscillations, noises, and harmonics of electromotive force. However, the average torque at a steady state is lower than without a skewing design. The finite element analyses are performed at peak torque operating points to compare both motor designs without and with the skewing rotor. A prototype of a servomotor with skewing rotor is produced and put through testing on a test bench. The suggested motor design is validated by experimental results.

Bài báo trình bày nghiên cứu, tính toán, thiết kế và tối ưu hóa hiệu suất động cơ servo ứng dụng trong băng chuyền. Trước tiên, từ yêu cầu di chuyển của băng chuyền, các yêu cầu đặc tính của động cơ nghiên cứu được xác định sau các bước tính toán chi tiết. Sau đó, nghiên cứu sử dụng các thuật toán tối ưu để tìm giá trị điện áp và hệ số trượt nhằm tối ưu hóa hiệu suất tại các điểm làm việc của động cơ. Bài báo đã xem xét và thiết kế ba động cơ với cấu hình và mật độ dòng điện khác nhau, qua đó có thể đánh giá, so sánh về khối lượng, hiệu suất và độ tăng nhiệt. Kết quả thiết kế tối ưu động cơ servo có ý nghĩa quan trọng trong việc lựa chọn động cơ phù hợp nhất về chi phí, hiệu suất và thời gian đáp ứng cho một ứng dụng yêu cầu cụ thể.

This paper proposes the prototype of e-tail and the energetic system model for all electric long-tail boat equipping with solar panels. It offers many advantages over a traditional internal combustion engine (ICE) propulsion system, thanks to the combination of the electric powertrain and the solar panel. Besides low noise and zero-emission, characteristics of electric engine allow regenerative braking and starting the propeller in the water. The prototype of e-tail is presented. The energetic system model is built to sizing optimally the battery capacity depending on the consumption of the e-tail boat driven by the e-engine. The simulations results are performed on a test-case of Phong Nha cave tourism boat. With 5 solar panels and 4 kWh of battery capacity, the boat can operate independently without external power source at least 1 round-trip 4 days in a week in winter and maximum 2 trips per day every day in summer.

In this paper, air-cooling models are investigated numerically on a new design of metal fin heat sinks based on the motor of the motorcycle using the Computational Fluid Dynamics (CFD) package ANSYS Fluent.The standard k -ε turbulence model was used in the numerical simulation.The domain was a rectangular geometry, and the metal fins created in the numerical model had three types: square pin, circle short pin, and circle long pin.These metal fin models were heated by a heat source at a power of 150-200 W based on the working range of the motorcycle's motor.Also, the air velocity for cooling was in the range of 40-60 km/h based on the motorcycle's speed.The temperature contours of the three models were used to compare the heat dissipation.The results showed that the thermal resistance did not change significantly when the heat source was changed.Notably, the circle long pin had the best effectiveness in dissipating heat compared to the others.The results from this research were important information that will help design and develop the heat sinks of the motor in the future.

A high-performance electric motorcycle (HPEM) integrated charger-inverter (ICI) with an induction motor (IM) is proposed in this article. Typical components are shared in drive and charge modes, resulting in savings of weight, volume, and cost. A two-stage ICI for AC induction motor powertrain with power factor correction (PFC) and battery charger functions is considered. Despite high voltage ripple on the DC link, a high bandwidth nonlinear controller can reject such a drawback and adequately provide a constant current or constant voltage charging process. The simulation results of 7 kW ICI are provided to validate the effectiveness and feasibility of the proposed system. Finite element analysis (FEA) determines the torque and losses of IM in charging mode.

An Electric propulsion (E-propulsion) system for ASEAN (Association of Southeast Asian Nations) long-tail boat is proposed in this article. It offers several advantages over a traditional internal combustion engine propulsion system. Besides low noise and zero-emission, characteristics of electric engine (E-engine) allow regenerative braking and starting the propeller in the water. A design of E-engine has been achieved through finite element analyses and lump-parameter thermal simulations. It shows better performances than Honda GX270 internal combustion engine in terms of volume, weight, torque, and power. A full scale prototype of E-engine was manufactured. Experiments have been conducted on an engine test bench. Torque, power, efficiency and temperatures were well aligned with the simulation results.

Switched reluctance motor (SRM) and induction motor (IM) technologies are studied based on specific ASEAN Bangkok and Hanoi driving cycles. Range simulations and thermal analyses have been performed on standard driving cycles: ECE15 and WMTC Part 1 as well as ASEAN cycles: Bangkok driving cycle and Hanoi motorcycle driving cycles. The e‐scooter ranges vary from 44 to 99 km depending on driving cycle, motor technology, and number of passengers. Finally, prototypes of both motors are manufactured and tested on a high‐speed test bench. Some experimental results are reported in this paper. As a conclusion, despite differences in terms of performances, cost, and range, both drive systems are, however, suitable for electric scooter application. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

This paper presents an efficient method of estimation of rotor cage temperature for induction machine design, applied for electric and hybrid vehicles. This factor influences the torque produced by the induction machine with a field-oriented control algorithm. Equipping sensors to measure the temperature of a rotation component is expensive and is not representative of mass production. The approach of estimation of rotor cage temperature is based on the good knowledge of motor parameters and the estimation of the flux of the machine. For an accuracy inductance taking account of the saturation, the no-load test can be performed. The machine flux will be estimated taking account of the voltage drop of the system on the test-bench. The rapid prototyping in a real-time motor control platform will be presented that integrates this estimator of rotor temperature. We finally show the experimental testing results compared to the measurement of the rotor cage on a prototype asynchronous low-cost motor designing for battery electric city cars.

This paper proposes an optimal design “modern” approach for servomotors. This approach consists of the optimization algorithms at the initial analytical calculations and the modelling of the virtual prototype in order to reduce the costly and time-consuming prototyping loops of the “conventional” design method. The optimal design of a servomotor for robot application is verified by using finite element analysis (FEA) in terms of torque at low to high speeds. The thermal simulations based on lumped-mass model have been conducted in order to determine the operating duration of maximum and continuous performances of this machine. A prototype of asynchronous servomotor is manufactured and tested in the test-bench. Experimental results of electromagnetic (torque) and thermal (rising temperatures of different positions in the motor) measurements of peak and continuous performances at different speeds will validate the virtual prototype as well as this design method.

This article presents the optimal design and experimental prototype testing of a low-cost motor applied for a city battery electric vehicle, zero emission A-segment. Respecting the car performance specifications, the aluminum cage rotor induction machine is designed to reduce motor cost using totally enclosed fan-cooled technology and a commercial speed encoder of internal combustion engine. An optimization approach and finite elements analysis validation are coupled with thermal calculations and used to size the thermo-electromagnetic parts of the machine. The prototype is manufactured with full instrumentation. During the experiments, an indirect flux-oriented control model is built based on simulations in MATLAB/Simulink environment. Using this real time control platform, the motor control is calibrated on the prototype in test-bench, to ensure the optimum energy consumption and the current and speed regulations in the entire large operating range. Finally, the experimental prototype testing results are shared to show the ideal design solution in term of peak performances, efficiency, thermal and noise, vibration, and harshness behaviors.

This paper presents a method to optimally design electrical machines. Unlike the traditional design method “tries-and-errors iterative process”, the optimal design approach consists of combining optimization algorithms and multi-physics models to reach the optimum design. A case study of designing a standard industrial motor of 6 HP with multi-objectives and constraints is chosen in order to test this optimization methodology. The Pareto solution results of two conflicting objectives between the efficiency and the active mass of this machine are reached to help designers and customers selecting the best compromised design of motor of 6 HP in terms of cost and consuming energy.

This paper presents the optimal design and experimental prototype testing of a low-cost motor applied for a city battery electric vehicle (BEV), zero emission A-segment. Respecting the car specification performances, the aluminum cage rotor induction machine (IM) is designed to reduce motor cost using totally enclosed fan-cooled (TEFC) technology and commercial speed encoders of internal combustion engine (ICE) car. Optimization approach and finite elements analysis (FEA) modeling validation, coupling with thermal calculations are used to size the thermo-electromagnetic parts. After selecting suppliers for motor components, prototypes are manufactured. For the experimentation, first, the indirected flux oriented flux control model is built based on simulation in Matlab/Simulink environment. Then the motor control calibration is tuned on the prototype in test-bench in order to ensure the optimum energy consumption, the current and speed regulations in the entire large operating area. We finally show the experimental prototype testing results to validate the obtained design solution in terms of peak performances, efficiency, thermal and NVH behaviors.

This paper presents the design and a small scaling prototype of a direct drive wind turbine generator. First, the potential of wind energy in Vietnam is discussed. The electromagnetic parts of permanent magnet synchronous generator are sized using the optimisation approach based on the analytical model, aiming to minimize the active masse, taking into account the technical and manufacturing constraints. Then, the modelling of this optimal solution using Finite Element Analysis (FEA) method is simulated in transient mode, in order to verify certain physical phenomena in the generator. Finally, a prototype is manufactured and experimental results are shown.

Purpose This paper aims to propose a multiobjective branch and bound (MOBB) algorithm with a new criteria for the branching and discarding of nodes based on Pareto dominance and contribution metric. Design/methodology/approach A multiobjective branch and bound (MOBB) method is presented and applied to the bi-objective combinatorial optimization of a safety transformer. A comparison with exhaustive enumeration and non-dominated sorting genetic algorithm (NSGA2) confirms the solutions. Findings It appears that MOBB and NSGA2 are both sensitive to their control parameters. The parameters for the MOBB algorithm are the number of starting points and the number of solutions on the relaxed Pareto front. The parameters of NSGA2 are the population size and the number of generations. Originality/value The comparison with exhaustive enumeration confirms that the proposed algorithm is able to find the complete set of non-dominated solutions in about 235 times fewer evaluations. As this last method is exact, its confidence level is higher.

This work investigates two different motor drive technologies, switched reluctance motor (SRM) and induction motor (IM). They are designed optimally to meet the desired performances for electric scooters. The comparison of both motors is described in terms of performances and material cost. With the similar constraint, induction motor performs slightly better than switched reluctance motor. But this must be traded-off with higher weight and cost. Both drive systems are, however, suitable for electric scooter application. Finally, the range simulations are conducted on a European urban driving cycle, ECE15 driving cycle and a more realistic cycle, Bangkok driving cycle. The e-scooter ranges are varied from 36 to 109 km depending on driving cycle, motor technology and number of passengers.

The behavior of brushless DC motor with its drive and converter is described and highlights the requirements for accurate simulation at full-load operation. Results obtained with two commercial software packages are presented. Tricks for models developed with both softwares are provided in order to obtain good results. The simulation results are compared with measurements at no-load and full-load operations made on a prototype.

This paper proposes one approach for the ecodesign of an auxiliary transformer for the railway traction based on optimization methods. This approach is well suited to electrical devices that are very energy consuming and/or have a long life. A multiobjective problem is expressed to find the trade-off between the conflicting goals of the designer. The first one is to minimize the mass of the transformer and its cost. The second goal is to reduce the emission of gazes that contribute to green house effect. The life cycle analysis is used to build a model of the contribution to the global warming from the raw material extraction to the end of life of the product. This model is used jointly with economic and electromagnetic models in a multiobjective optimization to find the trade-off between the designer's goals, helping him to take a decision.