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To present results of research closely linked to real life applications and to resume the work of a period of a few years.

The combination of finite‐element method (FEM) and boundary‐element method is applied to simulate the electromagnetic, mechanical, and acoustic behaviour of an induction machine with squirrel‐cage rotor. The paper gives an overall view of the workflow and the implemented mathematics, starting off with the two‐dimensional, transient electromagnetic simulation and the succeeding three‐dimensional, static electromagnetic simulation. Theory and results of the mechanical and acoustic simulations are discussed.

A main result of the research work is that the simulation of the acoustic behaviour of an electrical machine is very time‐consuming. Furthermore, geometry adoption, especially of the mechanical model, is very sensible.

Using the FEM for simulation of structure dynamic problems is often limited to how the boundary layers are handled. In real life materials are not “connected” but glued or clamped. Therefore, the behaviour can only be adapted by manipulating the material parameters. There are other methods known for simulation, which could be applied. On the other hand, measurements could be used for iterative parameter adoption.

A significant result of the work is that the results obtained only allow for comparison. Exactness is more a question of modelling the real behaviour than matching the results to measurement in terms of values.

This paper gives an overview of how to simulate the complete chain from electromagnetics to acoustics of an electric machine.

This paper describes a thermal and electrical model, used at Robert Bosch GmbH for the design of an innovative motor for a water‐pump. In addition, it offers an example of a highly integrated mechatronic system. A bonded‐ferrite inner rotor has been developed with an integrated front centrifugal impeller which is driven by the magnetic interaction of a rotating field created by claw‐poles. The two phase unipolar coil arrangement is fed by an internal circuit using two MOSFETS controlled by the commutation signal from a bipolar Hall‐IC. This is the first mass‐production example of an electrical machine for an automotive application where the claw pole topology is used to realise the armature of the motor (i.e. the rotating field) and not the excitation field.

Disturbing vibrations and noise of electrical machines are gaining impact. The paper aims to focus on the necessity of estimating the electromagnetic, structure‐dynamical, and acoustic behaviour of the machine during designing and before proto‐typing.

An adequate tool is numerical simulation applying the finite‐element method (FEM) and the boundary‐element method (BEM) allowing for the structured analysis and evaluation of audible noise also caused by manufacturing tolerances.

The simulated results show good accordance to measurement results. The methods and simulation tools allow the analysis and evaluation of every type of energy converter with respect to its electromagnetic, structure‐dynamical and acoustic behaviour.

The methods developed and proved can be applied to any electromagnetic device in general.

The purpose of the paper is to evaluate theoretically and experimentally the static and dynamic characteristics of a single‐phase claw‐pole motor using soft magnetic composite (SMC) for the stator core.

On the basis of the static characteristics, which are measured and obtained from a series of 3D FE magnetostatic solutions, the dynamic characteristics are simulated according to a proposed control strategy. The same strategy is tested in dSpace control environment. Apart from the evaluation of the prototype SMC motor, some study has been made in order to improve the existing motor design.

The static characteristics of the single‐phase claw‐pole motor have been modelled in 3D FE magnetostatic solver, where the rotor position and stator current have been changed. The characteristics compare well with the measurements, while the discrepancy with the cogging torque waveform needs further analyses and experiments to explain the real magnetization pattern of the plastic bounded ferrite magnet‐ring and the influence of magnetic hysteresis. The 3D FE magnetostatic optimization routine shows the maximum quantities for magnetic coupling and static core loss. Furthermore it is used to obtain the improved pole distribution so that the resting position of the unexcited motor co‐aligns at the position of the maximum electromagnetical torque. This is achieved by changing the angular width of claw‐poles. The specific output of the maximum coupling torque from the single‐phase claw‐pole motor can be increased from the recent 0.1 to 0.6 Nm/kg at a temperature rise of 60°. The simulations of dynamical characteristics show a good correlation with the experiments where the same control system in Simulink is applied to the prototype via dSpace. It is practically easier to implement a simple control strategy for the direct current controlled voltage source inverter. A more advantageous control system needs to be applied for the sampled current controller.

The influence of the magnetization of a multi‐pole magnet ring is not considered while computing the static characteristics in 3D FE magnetostatic solver.

The evaluation of the realistic magnetization pattern in the magnet aggravates the proper theoretical evaluation of static characteristics.

The design of a small size powder core motor is faced with the complexity of evaluating properly the static characteristics, while the magnetization pattern is not exactly known. The broad search here is for an efficient tool to visualize the output of the 3D FE optimization for an improved design.

Nowadays, the determination of the acoustic radiation of electric machines is of particular interest, because legal regulations restrict the maximum audible noise radiated by technical devices such as electrical machinery. The purpose of this paper is to analyze the electromagnetic excited structure‐borne sound and air‐borne noise of an AC servo drive.

This paper presents the required steps for the multiphysics acoustic simulation of electrical machines to evaluate its noise behaviour. This numerical approach starts with the electromagnetic force‐wave simulation. The computation by a structure dynamic model determines the deformation of the mechanical structure due to the force‐waves. The final step of the simulation approach consists of the computation of the acoustic radiation.

For the electromagnetic simulation analytical and numerical methods are combined to gain some acceleration of the entire multiphysics simulation approach. This combination offers additionally a detailed understanding of the noise generation mechanism in electrical machines.

Particular attention is paid to the structural‐dynamic model. Modelling of microstructures, such as the laminated iron core or insulated coils, is memory and computational expensive. A systematic material homogenisation technique, based on experimental‐ and numerical modal analyses, yields a higher accuracy at lower computational costs when compared to standard numerical approaches. The presented multiphysics simulation is validated by measurements. The methods are presented by means of a case study.

This paper aims to propose a new topology of direct current (DC) machine using claw-pole stator to replace standard DC starter in micro-hybrid vehicles. The main interest of such a topology is the reduction of copper volume.

The design of the claw-pole machine is based on a multi-objective optimization of several topologies, based on a three-dimensional (3D) reluctance network modeling. The 3D finite element (FE) model is used to check the results of the optimization, and a prototype is manufactured and tested with satisfactory results.

The claw-pole topology with wave-shape windings allows to replace the current DC series classical starter because of to its copper volume saving.

This model is only limited to the optimization of the claw-pole stator for a fixed geometry of the rotor.

The research outcome shows that claw-pole machine can replace the series-excited DC machines of starters and at the same time achieve the same performance at reduced copper volume.

The paper deals with a new DC machine topology to reduce the copper volume through the suppression of the classical stator end-windings. The use of Claw-Pole inductors ensures this copper reduction.

This paper deals with 3D finite‐element calculation of eddy currents in the claws of a claw‐pole alternator taking the rotational geometry movement into account. Two transient edge‐based vector formulations are utilised. The reduction of the model to only one pole pitch in combination with a special boundary pairing in the air gap for the applied lock‐step method is presented. Calculations of varying material conductivity are performed with simplified end windings. The speed characteristics of the eddy currents with real conductivity and realistic end windings concludes the paper.

Finite‐element simulations of induction machines with squirrel‐cage rotor require transient solution algorithms. For this reason a transient 2D solver is utilized which takes rotational movement of the rotor into account. Its formulation and the time‐step algorithm are given. Two different kinds of eccentricity of the rotor and their combination are defined and studied. The three motor variants are computed and the torque, the net force, and the surface‐force density are compared in time and frequency domain.

Business model (BM) canvases have been used in educational institutions and business incubators for over a decade to assist students and start-up entrepreneurs in developing their business projects. Given the urgency of tackling sustainability challenges, several tools have emerged to stimulate sustainable business modeling (SBM). However, these tools are often too complex for nonexperts in business modeling or sustainability, and thus insufficiently user-friendly for educational contexts. This study aims to address this pedagogical gap by describing the design process of the responsible business model canvas (RBMC).

The authors relied on a design science research methodology involving the active participation of end users, entrepreneurship educators, business coaches and external partners. The authors proposed four criteria and ten subcriteria to analyze existing SBM canvases based on their user-friendliness and to design the initial prototype of the RBMC. The RBMC was subsequently tested in various settings, including classroom assignments and business incubation programs, with over 1,000 university students. The tool was refined and assessed throughout the development process, incorporating feedback from focus groups with start-up entrepreneurs.

Through the development process, the authors created a user-friendly tool to help novice student and start-up entrepreneurs integrate sustainability into their BMs: the RBMC. The canvas consists of 14 building blocks grouped into four areas: consistency (mission, vision, values), desirability (value propositions, customer segments, users and beneficiaries, customer relationships and channels), feasibility (key activities, key resources, key partners and stakeholders and governance) and viability (cost structure, revenues streams, negative impacts and positive impacts).

The research methods and user-friendliness criteria in this study can be applied in other contexts to design tools to support sustainable entrepreneurship education. While the RBMC is currently being used in several educational institutions throughout the world, its impacts in different pedagogical and cultural settings require further validation.

The RBMC is a user-friendly tool to introduce students and start-up entrepreneurs to SBM. It helps raise users’ awareness about sustainability concerns, challenging them to consider issues they might have otherwise overlooked. Some participants even shifted their outlook and were motivated to develop a long-term vision integrating compensatory, mitigative or corrective actions into their BMs.

The RBMC is the outcome of a balanced approach that combines both pragmatic (i.e. user-friendliness) and normative (i.e. sustainability) perspectives. It provides users with a systematic approach for integrating and applying sustainability issues in their business projects.

The purpose of this paper is to identify the role intermediaries can play in an small to medium‐sized enterprise's (SME's) pursuit for corporate sustainability with a focus on eco‐innovation. The research identifies drivers and barriers for eco‐innovation, and highlights effects induced through collaboration between SMEs and local authorities, on the one hand, and consultancies, on the other.

This paper is based on an exploratory qualitative interview study among German SMEs of the metal and mechanical engineering industry that have participated in “Ecoprofit”, an intermediary based program that aims at introducing organizations to the concept of sustainable development through implementation of eco‐innovations.

The key findings are that first, the proactive approach by a public intermediary (here local authority) is one essential push factor to trigger eco‐innovations in SMEs with low absorptive capacity. Second, it is found that SMEs may need facilitation for eco‐innovation from different types of intermediaries (public and private) with different levels of support, which can range from customized and individual to more loosely held support, such as networks.

This study discusses the challenges of corporate sustainability with a focus on eco‐innovations for SMEs and proposes a “complex intermediary” consisting of a local authority and consultancies as one means to engage SMEs in sustainability. Moreover, it focuses on SMEs in the B2B context, organizations that are often overlooked despite their vast impact. Furthermore, by using a single industry approach, in‐depth findings for the metal and mechanical engineering industry are presented.