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The electromechanical planetary transmission system has the advantages of high transmission power and fast running speed, which is one of the important development directions in the future. However, during the operation of the electromechanical planetary transmission system, friction and other factors will lead to an increase in gear temperature and thermal deformation, which will affect the transmission performance of the system, and it is of great significance to study the influence of the temperature effect on the nonlinear dynamics of the electromechanical planetary system.

The effects of temperature change, motor speed, time-varying meshing stiffness, meshing damping ratio and error amplitude on the nonlinear dynamic characteristics of electromechanical planetary systems are studied by using bifurcation diagrams, time-domain diagrams, phase diagrams, Poincaré cross-sectional diagrams, spectra, etc.

The results show that when the temperature rise is less than 70 °C, the system will exhibit chaotic motion. When the motor speed is greater than 900r/min, the system enters a chaotic state. The changes in time-varying meshing stiffness, meshing damping ratio, and error amplitude will also make the system exhibit abundant bifurcation characteristics.

Based on the principle of thermal deformation, taking into account the temperature effect and nonlinear parameters, including time-varying meshing stiffness and tooth side clearance as well as comprehensive errors, a dynamic model of the electromechanical planetary gear system was established.

Concept design practices in engineering are not common across industry or academia. There are a number of well-known tools and methods acknowledged as useful in facilitating concept designing, that is, to assist idea generation, aid evaluation and final selection of one winning concept from many. Combinations of these popular concept design tools and methods provide various systematic methodologies by which practitioners propose to conduct or teach concept designing. In this paper, effective practices and trends are observed through the application of a specific concept design methodology over a range of different projects in electromechanical systems design.

The concept design methodology utilised in this study has been developed through the adoption of various tools and methods shown to be beneficial to concept designing, supported by previous positive experiences and successful utilisation associated with electromechanical systems research projects in academia. Each stage of the methodology is discussed and six case studies are presented, which are used to explore effective practices for concept designing.

Analysis of the case study data reveals the most popular criteria for the selection of concepts in electromechanical systems design, the number of selection criteria and number of initial concepts ideally required to converge on a final winning concept more efficiently, that is without the need for a more detailed second stage of selection using performance metrics.

Rarely are detailed studies undertaken in concept design, first, to address the justification for the concept design methodology adopted and, second, to show how effective practices emerge through the analysis of non-subjective data over a number of concept design projects. Although the paper uses only six case studies in electromechanical systems design, it is hoped that the approach presented promotes the possible future development of a framework for verification of concept design methodologies across different products, sectors and user groups.

In the last few years, the understanding of environmental problems has grown. Car producers – original equipment manufacturers – are aiming to reduce fuel consumption and pollution. In order to fulfil these aims, new technologies have been launched. Many hydraulics systems have been removed and replaced with electric ones, e.g. power steering, water and oil pump, etc. In this paper, an electromechanical subsystem used in an automotive application is analyzed. The subsystem is composed of interior permanent synchronous magnet motor and electronic control unit. The range of mechanical output power for studied system is up to 1 kW. The aim of this paper is to compare electromechanical systems working with different on‐board voltage levels in order to find the optimum balance between motors' and electronics' efficiency. This will help to decrease the total system's weight, the consequence of which will decrease fuel consumption and reduce CO₂ emissions.

During the analysis, the reduced order modelling (ROM) techniques has been applied. First, with utilization of finite‐elemente‐methode the basic motor's parameter like: synchronous inductance and flux per pole as a function of the direct‐axis current and also the quadrature‐axis current are calculated. In the second step, these parameters are used in the system simulation. During this simulation, the maximum torque per ampere control strategy together with ROM techniques was used.

As a result, the performance of the system for different voltage levels has been obtained. Additionally, the important factors for an electromechanical system, such as maximum power density, sizing and cost of the total electromechanical system, have been compared.

The performed comparison shows that the cost optimized system should work with the higher voltage, where the electric motor size is reduced ca. 25 per cent. This result is also valid for different electromechanical systems in an automotive area, e.g. automated manual transmission, engine cooling and electric compressor.

It is the first paper, where electric power steering system design for different on‐board voltage levels has been systematically analyzed and compared. Results from this paper can be also applied to different electromechanical systems mounted in hybrid or electric cars.

An electrical revolution in the automotive sector was decided on at the end of 2008, when the European Parliament passed legislation of lower CO₂ emissions of new cars. This causes and forces the development of alternative concepts of propulsion systems and alternative fuels. These new trends of propulsion technologies such as hybrid and pure electric drive will have an impact on the entire design of cars. The purpose of this paper is to present an evolution of selected fractional horsepower electrical drives used in cars. Analysis of electromechanical components can be divided into two groups: the first one contains the currently used subsystems, e.g. electric power steering system, engine cooling systems, etc.; and the second one presents the development of new components, e.g. electric air‐conditioning compressor and other by‐wire technologies. Additionally, the development and trends of new materials and technologies used in electrical drives for the automotive industry are presented.

Performed analysis based on a review of the literature and the author's own research and experience in the area of electromechanical systems for automotive applications. During motor design, computer numerical simulation method, CAD and experiment were used. The development perspectives in the area of electromechanical systems in automotive area are presented. Additionally, the evolution of fractional horse power electric motors, with the influence of new developments in the area of electric vehicles, are analysed and presented.

The presented analysis shows that a change of technology from brush type motors into brushless is inevitable. Additionally, further miniaturization will be conducted using a higher energy permanent magnet. Furthermore, an increase of efficiency will be achieved by increasing the voltage level from 12 V to 48 V or even higher, e.g. 120 V.

This is the first paper, where, in a comprehensive way, developments of fractional horse power electromechanical systems for electric and hybrid vehicles are presented. The results of this paper can be utilized during the creation of the products' road‐maps in this area.

The purpose of this paper is to design an electromechanical actuator which can inherently tolerate a stuck or loose failure without any need for fault detection isolation and reconfiguration.

Generalized design methodology for a thrust vector control application is adopted to reduce the design iterations during the initial stages of the design. An optimum ball screw pitch is selected to minimize the motor sizing and maximize the load acceleration.

A high redundancy electromechanical actuator for thrust vector control has lower self-inertia and higher reliability than a direct drive simplex configuration. This configuration is a feasible solution for thrust vector control application because it offers a more acceptable and graceful degradation than a complete failure.

Future work will include testing on actual hardware to study the transient disturbances caused by a fault and their effect on launch vehicle dynamics.

High redundancy electromechanical actuator concept can be extended to similar applications such as solid motor nozzle in satellite launch vehicles and primary flight control system in aircraft.

High redundancy actuators can be useful in safety critical applications involving human beings. It can also reduce the machine downtime in industrial process automation.

The jam tolerant electromechanical actuator proposed for the launch vehicle application has a unique configuration which does not require a complex fault detection isolation and reconfiguration logic in the controller. This enhances the system reliability and allows a simplex controller having a lower cost.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

This paper presents a methodology based on Multiobjective Genetic Algorithms (MOGAs) for the design of electrical engineering systems. MOGAs allow one to optimize multiple heterogeneous criteria in complex systems, but also simplify couplings and sensitivity analysis by determining the evolution of design variables along the Pareto‐optimal front.

To illustrate the use of MOGAs in electrical engineering, the optimal design of an electromechanical system has been investigated. A rather simplified case study dealing with the optimal dimensioning of an inverter – permanent magnet motor – reducer – load association is carried out to demonstrate the interest of the approach. The purpose is to simultaneously minimize two objectives: the global losses and the mass of the system. The system model is described by analytical model and we use the MOGA called NSGA‐II.

From the extraction of Pareto‐optimal solutions, MOGAs facilitate the investigation of parametric sensitivity and the analysis of couplings in the system. Through a simple but typical academic problem dealing with the optimal dimensioning of a inverter – permanent magnet motor – reducer – load association, it has been shown that this multiobjective a posteriori approach could offer interesting outlooks in the global optimization and design of complex heterogeneous systems. The final choice between all Pareto‐optimal configurations can be a posteriori done in relation to other issues which have not been considered in the optimization process. In this paper, we illustrate this point by considering the cogging torque for the final decision.

We have proposed an original quantitative methodology based on correlation coefficients to characterize the system interactions.

To present theories for total cost of ownership (TCO) methodology in assembly system trade‐off analysis and to show benefits of the methodology as a decision support in system selection.

The developed TCO methodology is a combination of factory simulation, system performance and loss factor evaluation using overall equipment efficiency, system life cycle costing, and assembled unit cost analysis including cost of bad quality and rework.

The purchase price of equipment is just one cost element in the comparison. TCO shows how important it is to analyse all the cost, direct and indirect, incurred throughout the life cycle of an equipment, including acquisition and installation, operations and maintenance, and end‐of‐life management. TCO methodology pinpoints costs that could be easily underestimated, such as quality and rework as well as all the costs of running the system.

The methodology is partially based on semiconductor industry standards and other asset comparison methodology, which are now integrated and applied also for electromechanical final assembly. Development continues.

The methodology is useful in system integrator and end‐user collaboration, where both can use similar formulae in system evaluation and trade‐off analysis. Integration to component‐based simulation adds system visualisation and simulation analysis and combines system configuration with cost analysis into a tool for the sales engineer.

Integration of different analysis methods improves the quality of decisions. The TCO methodology is a systematic way to analyse system cost and performance issues. With proper use of the TCO methodology it is possible to justify investments to automation and modular re‐configurable hardware.

This paper aims to propose a methodology to develop an organizational memory to benefit from team knowledge and to make the design of electromechanical devices processes more efficient.

Different frameworks and methods were analyzed from literature, obtaining key ideas to be included in the methodology developed and considering other approaches to apply in team knowledge about design processes. The research was conducted as a case study in a Mexican small and medium-sized enterprises dedicated to the manufacturing and installation of electromechanical devices where the methodology was implemented.

A five-stage methodology was developed which consisted of preparation, identification, capture & storage, dissemination & application and finally the evaluation & feedback stage. An implementation of the described processes was carried out, which was materialized into a technological tool that represents the organizational memory where knowledge was captured, organized and disseminated.

This study offers guidelines that can be applied in other organizations where team knowledge on design processes have not been adequately used for company’s improvement. The application of this methodology could be a strategy that enabled team knowledge to store their experience. This knowledge could then be consulted and recovered by the workgroup in an effective manner to solve new problems.

A methodological proposal to develop an organizational memory about team knowledge was developed. To evaluate the impact of the methodology implementation, a variety of indicators were proposed, which were classified as economic, organizational and performance indicators.

The electromechanical brake system is leading the latest development trend in railway braking technology. The tolerance stack-up generated during the assembly and production process catalyzes the slight geometric dimensioning and tolerancing between the motor stator and rotor inside the electromechanical cylinder. The tolerance leads to imprecise brake control, so it is necessary to diagnose the fault of the motor in the fully assembled electromechanical brake system. This paper aims to present improved variational mode decomposition (VMD) algorithm, which endeavors to elucidate and push the boundaries of mechanical synchronicity problems within the realm of the electromechanical brake system.

The VMD algorithm plays a pivotal role in the preliminary phase, employing mode decomposition techniques to decompose the motor speed signals. Afterward, the error energy algorithm precision is utilized to extract abnormal features, leveraging the practical intrinsic mode functions, eliminating extraneous noise and enhancing the signal’s fidelity. This refined signal then becomes the basis for fault analysis. In the analytical step, the cepstrum is employed to calculate the formant and envelope of the reconstructed signal. By scrutinizing the formant and envelope, the fault point within the electromechanical brake system is precisely identified, contributing to a sophisticated and accurate fault diagnosis.

This paper innovatively uses the VMD algorithm for the modal decomposition of electromechanical brake (EMB) motor speed signals and combines it with the error energy algorithm to achieve abnormal feature extraction. The signal is reconstructed according to the effective intrinsic mode functions (IMFS) component of removing noise, and the formant and envelope are calculated by cepstrum to locate the fault point. Experiments show that the empirical mode decomposition (EMD) algorithm can effectively decompose the original speed signal. After feature extraction, signal enhancement and fault identification, the motor mechanical fault point can be accurately located. This fault diagnosis method is an effective fault diagnosis algorithm suitable for EMB systems.

By using this improved VMD algorithm, the electromechanical brake system can precisely identify the rotational anomaly of the motor. This method can offer an online diagnosis analysis function during operation and contribute to an automated factory inspection strategy while parts are assembled. Compared with the conventional motor diagnosis method, this improved VMD algorithm can eliminate the need for additional acceleration sensors and save hardware costs. Moreover, the accumulation of online detection functions helps improve the reliability of train electromechanical braking systems.