JMAG is constantly being worked on to achieve highly accurate and high-speed simulation. JSOL would like to share our progress from the past year including parallel solvers to accelerate speed as well as GUI improvements aiming for increased productivity of analysis workflow. Analysis technologies we are currently focusing on and our plans for incorporation will also be covered in this presentation. Design exploration is an important topic this year. This presentation will discuss the present and future of JMAG.

Nowadays an impressive effort is done to significantly reduce the calculation time and improve the performance of electromagnetic calculation of rotating electrical machines. With increasing availability of high performance computing and the acute interest for detailed electromagnetic evaluation, the simple 2D based approaches may have come to their limits. A comprehensive understanding and modelling of electromagnetic mechanism is required to accurately evaluate the performance of an electrical machine. Therefore, in this paper the end-winding stray field is analyzed and the additional iron losses in the end region of the stator core are presented and assessed. For this purpose, enhanced 3D finite element models, including the complex end-winding geometry, are computed on a parallel distributed high performance computing system. To emphasize the benefit of this enhanced 3-D finite element modelling, two different study case examples are shown.

High efficiency of electrical motors used in industry as well as in electrical cars is getting increasingly important. New directives for industrial drives require novel motor designs with higher efficiency and new efficient motors for traction drives are developed to improve the range of electrical cars. The development time for new motors is a very important aspect for being competitive in today’s market. Therefore, the quality of FEM simulations, as well as prototyping, are very important to achieve the specifications accurately. However, FEM simulations use material properties measured under optimal conditions without any cutting effects. Furthermore, the production processes of prototypes differ from those of the series production. In order to investigate the differences, four motors with different fabrication methods were built and measured for comparison of the production influences in the final application. Additionally, FEM simulations of the motors with material data taken from laser cut and stamped samples were performed.

The following topic presents the influence of variation in various geometric parameters of claw-pole topology on the performance of machine used in automotive application. Due to three-dimensional flux distribution in the claw-pole topology, variation in geometric parameters of the claw-poles results into change in performance of the machine. Also because of the 3D claw-pole structure, the geometry modeling of the claw-pole machine is quite complex and requires lot of geometric operations during modeling it in a computer-aided-design software. Hence, the claw-pole machine is modeled directly in the JMAG geometry editor so as to utilize the same for finite element analysis. The geometric parameters which have been varied are claw core outer diameter, claw inside radius, claw side plate thickness and claw undercut angle, and the performance of the machine has been evaluated for the complete operational speed range from low speed of 600 rpm to high speed of 18,000 rpm. By carrying out the aforesaid variations, it has been observed that there is a significant change in torque during low speed operation.

The supremacy of radial flux motors is ubiquitous and there are several reasons for that. As most of motors are made from thin laminations, radial motors are the natural choice due to the simplicity and performance. A study has been performed with the help of JMAG and its 3D capabilities to evaluate an Axial Flux Motor (AFM) made of Soft Magnetic Composites (SMC). The motor consists of 12 slots, 14 poles with a rated output power of 6 kW. Husqvarna Construction division has a motor named Prime which is used in several products like Drill Machine, Power Cutter, Wall Saw among others. The efficiency, weight and reliability are crucial for these professional tools. Power dense motors are achieved by usage of external cooling fluid as water and internal cooling as oil for heat transfer/distribution. The analysis and results are fully automated by scripts in Microsoft Excel, SolidWorks and JMAG. The proposed AFM should provide the desired performance with a simple and intuitive assembly process. The mechanical design has been made in CATIA and prototypes are under evaluation.

As heavy rare earth elements occur less than one-tenth as often in ore deposits as light rare earth elements. Future usage needs to be reduced in light of the resource risks and costs. As such, a method was developed to recover reductions in coercive force and prevent demagnetization temperature from reducing without adding any heavy rare earth elements.

First, a heavy rare-earth-free magnet was developed by hot deformation, which limits growth of crystal grain size, and relationships were clarified between coercive force and optimal deforming temperatures, speed, and total rare earth amounts for heavy rare-earth-free magnets.
Second, it was made clear that the permeance coefficient can be increased by reshaping the flux barriers, and that the developed hot deformed magnet can be adopted.
In this study, a new motor was developed using heavy rare-earth-free hot deformed magnets with performance and marketability equal to or higher than those of traction motors equipped in one-motor sport hybrid systems.

The thesis investigates the replacement of an existing X-ray tube induction machine rotor with that of a synchronous reluctance machine. The feasibility of simple rotor replacement was investigated by finding synchronous reluctance machine rotor shapes capable of providing the same torque output as the original induction machine rotor in combination with the original stator. Using 2D-Finite Element Analysis software JMAG (JSOL Corporation), characterising parameters of three appropriate synchronous reluctance machine rotors were found and the rotor and stator losses of the synchronous reluctance machines are compared to the losses of the original induction machine. From the rotors studied in this thesis, the most promising is an axially-layered rotor which showed more than 50% reduction of total losses for the same torque output. Considerations for future work include ensuring compatibility with the X-ray tube vacuum environment.

After a short introduction in the basics of synchronous reluctance machine design, the implementation of a straightforward flux barrier design method in JMAG is explained step by step. The design method needs only a few variables, which are varied in a parameter study. Due to saturation effects, the inductances in d- and q-axis of the synchronous reluctance machine are not constant and the adjustment of an operating point needs some simulations to get the inductance map by the variation of the d- and q-currents. The combination of finite-element studies with the basic equations of synchronous reluctance machines leads to a more time-efficient method to find these operating points, which are used to compare different rotor designs. In addition to the electromagnetic design of the synchronous reluctance machine, the mechanical design is also focused, since mechanical ribs are needed to stabilize the rotor structure. At the end, an efficiency map is calculated in JMAG with the operating points of the IEC 60034-2-3 and compared with the measured efficiency map obtained by this method.