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An analytical approach is preferred to carry out the harmonic modelling of power electronics converters because it is generally faster than time simulation chained with FFT. However, the difficulty of such an approach is to build the model and to manage the uncontrolled commutations that occur in the studied static converter, and also to deal with large equations. The purpose of this paper is to propose an aid in the frequency modelling of the drive elements, in the frequency domain, including all key parameters for sizing aim i.e. a way to optimize the EMC filter using different algorithms.

The paper aims to propose an aid to create such models, and to assure its good solving, i.e. that the correct operating mode is represented. So, the solving problem is formulated as an optimization problem under constraints, to solve this difficulty.

The difficulty is to be sure to deal with the good operating mode of the static converter when soft or uncontrolled commutations occur. So, the model is formulated as a constrained optimization problem. The paper proposes a symbolic approach, that allows to build automatically the frequency model. It is translated to be solved in Matlab.

The approach does not fit for static converters with a control implying numerous commutations per operating period. However, the approach deals with natural and soft commutations.

The modelling is based on the use of linear components and ideal switches.

The purpose of this paper is to study the high-frequency impacts of fast switching wide-bandgap transistors on electronic and motor designs. The high-frequency power converters, dedicated to driving high-speed motors, require specific models to design predictively electronic and motors.

From magnetic and electric models, the high-frequency parasitic elements for both electronics and motor are determined. Then, high-frequency circuit models accounting for of parasitic element extractions are built to study the wide bandgap transistors commutations and their impacts on motor windings.

The results of the models, for electronics and motors, are promising. The high-frequency commutation cell study is used to optimize the layouts and to improve the commutation behaviours and performances. The impact of the switching speed is highlighted on the winding voltage susceptibility. Then, the switching frequency and commutation rapidity can be both optimized to increase the performance of motor and electronics. The electronic model is validated by experimentations.

The method can be only applied to the existing motor and electronic designs. It is not taken into account in an automized global high-frequency optimizer.

Helped by magnetic and electric FEA calculations where the parasitic element extractions are performed. The switching frequency and commutation rapidity can be both optimized to increase the performance of motor and electronics.

This paper is devoted to the investigation of position estimation for a brushless DC machine using only their stator currents. The first application is for a hybrid electric vehicle, where the generator will be used as a motor to start the internal combustion engine (ICE).

This paper describes how to estimate the rotor position of a brushless DC (BLDC). Two different strategies, both based on stator currents, will be used: one for low speeds to start the ICE, and one for normal speeds for future applications in a pure electric vehicle (EV). The first one uses an estimation method based on core saturation and the second one is based on the determination of the current slopes on two of the three phases. The algorithms proposed neither needs to measure any machine parameters, nor the back emf. The methods use the information contained in the current magnitudes and slopes, and the machine mechanical speed. The system was implemented using a Digital Signal Processor (TMS320F241), which controls the phase currents and makes all the calculations required for position estimation. Additionally, the PWM signals are transmitted through a fiber optic link to minimize noise production and error on commutations.

The papers shows how an internal combustion engine can start using this approach in a brushless motor and keep it synchronized.

This work is being applied to a hybrid electric vehicle.

The paper proposes a new way to start the internal combustion engine for hybrid vehicle applications through the estimation of the magnet's position. It also shows a way to estimate the position at other speeds for battery charging of the vehicle.

This paper aims to study a multi-level reinjection current source converter (MLR-CSC) that adds attracting properties such as the self-commutation and pulse multiplication to the thyristor converter, which is of great significance for increasing the device capacity and reducing current harmonics on the grid side. Particularly, designing advantageous driving methods of the reinjection circuit is a critical issue that impacts the harmonic reduction and operation reliability of the MLR-CSC.

To deal with the mentioned issue, this paper takes the five-level reinjection current source converter (FLR-CSC), which is a type of the MLR-CSC, as the research object. Then, a method that can fully use combinations of five-level reinjection switching functions based on the concept of decomposition and recombination is proposed. It is worthy to mention that the proposed method can be easily extended to other multi-level reinjection circuits. Moreover, the working principle of the three-phase bridge circuit based on semi-controlled thyristors in the FLR-CSC that can achieve the four-quadrant power conversion is analyzed in detail.

Finally, the simulation and experimental results of FLR-CSC verify the effectiveness of the proposed reinjection circuit driving method and the operating principle of four-quadrant power conversion in this paper.

The outstanding features of the proposed driving method for FLR-CSC in this paper include combinations of reinjection switching functions that are fully exploited through three simple steps and can be conveniently extended to other multi-level reinjection circuits.

The principal intention behind the activity is to regulate the speed, current and commutation of the brushless DC (BLDC) motor. Thereby, the authors can control the torque.

In order to regulate the current and speed of the motor, the Multi-resolution PID (MRPID) controller is proposed. The altered Landsman converter is utilized in this proposed suppression circuit, and the obligation cycle is acclimated to acquire the ideal DC-bus voltage dependent on the speed of the BLDC motor. The adaptive neuro-fuzzy inference system-elephant herding optimization (ANFIS-EHO) calculation mirrors the conduct of the procreant framework in families.

Brushless DC motor's dynamic properties are created, noticed and examined by MATLAB/Simulink model. The performance will be compared with existing genetic algorithms.

The presented approach and performance will be compared with existing genetic algorithms and optimization of different structure of BLDC motor.

In United States v. United Shoe Machinery Corp., United Shoe Machinery (USM) was found guilty of illegal monopolization due to its leasing practices. Existing scholarship on this case largely focuses on the issue of leasing versus selling. In this article, we provide a more comprehensive analysis of this important decision. In addition, we examine USM’s antitrust experience before and after the famous 1953 case. We find that USM’s business practices were largely procompetitive and, therefore, did not warrant condemnation.

Measurement uncertainty calculation is an important and complicated problem in digitised components inspection. In such inspections, a coordinate measuring machine (CMM) and laser scanner are usually used to get the surface point clouds of the component in different postures. Then, the point clouds are registered to construct fully connected point clouds of the component’s surfaces. However, in most cases, the measurement uncertainty is difficult to estimate after the scanned point cloud has been registered. This paper aims to propose a simplified method for calculating the uncertainty of point cloud measurements based on spatial feature registration.

In the proposed method, algorithmic models are used to calculate the point cloud measurement uncertainty based on noncontact measurements of the planes, lines and points of the component and spatial feature registration.

The measurement uncertainty based on spatial feature registration is related to the mutual position of registration features and the number of sensor commutation in the scanning process, but not to the spatial distribution of the measured feature. The results of experiments conducted verify the efficacy of the proposed method.

The proposed method provides an efficient algorithm for calculating the measurement uncertainty of registration point clouds based on part features, and therefore has important theoretical and practical significance in digitised components inspection.

This study seeks to examine the analysis and control of a three‐switch three‐phase inverter (TSTPI)‐fed brushless DC motor (BDCM) as well as the comparison of its performance with those yielded by six‐switch three‐phase inverter (SSTPI)‐fed BDCM drives.

The analysis of the six operating sequences of the TSTPI‐fed BDCM drive followed by the implementation of a dedicated self‐control strategy in such a drive and the comparison of its performance with those given by an SSTPI‐fed BDCM drive.

The dedicated self‐control strategy required the integration of a torque loop in the implementation scheme in order to reduce torque ripple amplitude during sequence‐to‐sequence commutations. It has been shown that the TSTPI‐fed BDCM offers high performances which are almost the same as those of the SSTPI‐fed BDCM.

This work should be extended by building a test bench made up of a TSTPI‐fed BDCM and the comparison between simulation results and experimental ones.

A 50 per cent reduction in cost and compactness, and a 50 per cent increase in reliability make the TSTPI an interesting candidate especially in large‐scale production applications such as the automotive industries.

The paper proposes an approach to improve the cost‐effectiveness and the volume‐compactness of BDCM drives which represents a crucial challenge in electric and hybrid propulsion systems. It is the best solution compared with the conventional SSTPI and the four‐switch three‐phase inverter.

The purpose of this paper is to propose a new instantaneous torque control method for switched reluctance motor (SR motor) and presents experimental data in electric vehicle (EV) application.

The proposed control method uses two kind of techniques: a flux‐based commutation technique prevents the negative phase torque always. On the other hand, a direct phase‐torque distribution technique gives suitable each phase‐torque command under limited DC voltage. These techniques can track motor torque to the command. These control schemes are implemented on a small processor and a field programmable gate array.

The experimental results of the EV show small torque ripple at low speed on both acceleration and regenerative braking. Changing the parameter of the current stop angle can improve torque ripple at high speed. The proposed method can effectively control motor torque.

The proposed method can reduce torque ripple but the implementation is very simple. The proposed control method can be used for any applications. So, that contributes to expand the application of SR motors.

The proposed control scheme requires just static torque curve obtain by finite element analysis or simple experiments. Complex parameters, such as nonlinear inductance, current to torque profiles, and other heuristics parameters, are not necessary. The proposed control is simple but practical.

This case discusses the issue and challenges faced by MoveInSync during the COVID-19 pandemic lockdown and its Corporate Social Responsibility (CSR) initiative that contributed to the employees’ wellbeing. India was significantly hit by the pandemic and the impact has been severe. The corporate sector of India irrespective of the company size has worked for hand in hand with the government to contribute to handling the pandemic. One such company is MoveInSync which offers transport and security operations to enhance employee commute space. Despite the COVID-19 pandemic severely impacting their business operations, MoveInSync continued its CSR effort to help the needy and cared for its own employees.