We will be reporting the development roadmap of JMAG and its latest features.
JMAG continually aims toward providing you the best simulation tool. This is by improving the usability of the user interface, the high-speed and highly accurate simulation engine, and the modeling technology to provide the ideal model in all stages of development. In addition, we have enhanced calculation processing to support large amounts of calculation to explore design space, and data management.
Stay tuned to the continuous evolution of JMAG.

In this presentation, we will discuss solution case studies using FEM, focusing on specific motor design issues taking into account motor needs such as performances and driving conditions.
Automotive motors are required to be high-powered, high-efficiency and high productivity. It was necessary to use high performance magnets in Toyota and we began to develop high performance motors using Nd-Fe-B magnets invented in the 1980s.
The first project was development of built-in motors with large torque for production equipments. We improved design method and production technology of motor using Nd-Fe-B magnets. Those motors were application-oriented motors in performance, shape and structure. During this time, FEM electromagnetic field analysis technology made large advances and contributed to meet the required torque characteristics of motors.
The second project was development of several application motors for automobiles. Their design issues were higher-performance in both torque and power, higher-efficiency, and extreme conditions in temperature and power source fluctuation. 3-D FEM and multiphysics analysis contributed to achieve the optimal design for required motors.

A campaign of dimensional measurement on a large number has brougt out some imperfections (as eccentricity, ovalization of stator or withdrawal of teeth) due to process.
We decided to carry out simulation with JMAG for each imperfections in order to understand their influence on the behaviour of claw Pole machines.

Substations located near residential districts in urban areas are required to use low-noise transformers. Noise generated by iron core vibration (excitation noise) has taken into consideration such factors as reduction of iron core magnetic flux density, improvement of material properties, iron core structure (joints/clamps) and residual strain by machining as part of the efforts to move forward with noise reduction. When excitation noise becomes quieter, noise accompanying load current (load current noise) sometimes becomes an issue after having been ignored while excitation noise was being dealt with.
Vibration of tanks that emit noise is considered that is transmitted through structural material or insulation oil to the tank. When the load current appears, the electromagnetic force occurs in the tank. As part of initiatives for predicting load current noise or noise reduction, we used JMAG for an analysis of electromagnetic force during current flow.
We will describe the examples of numerical analysis.

In recent years, our production technology field started incorporating a method using high-frequency heating methods. Although production efficiency has increased significantly, since it has different characteristics compared to conventional heating methods, it takes cost and time to extract conditions if only through actual machine verification.
Running the analysis evaluation in JMAG-Designer’s frequency response – thermal coupling analysis in parallel with actual machine verification will narrow down the combinations of actual machine evaluations and allows clear explanations of the confirmed phenomenon.
We will be presenting two case studies applied in production technology and possible future examples in the fields of production and design for application of the magnetic field – thermal coupling analysis.

Our primary focus is on products such as magnetos (generators), starter motors, ignition units, and ignition coils which are used in motorcycle and marine engines, mainly in the engine component field.
We also work on electric hybrid automobile PAS drive units.
Because motorcycle engines have an impact on the external appearance of vehicles, it is necessary to account for the appearance of engine components during development. We are always required to quickly pick out the optimum specification from multiple specification drafts in accordance with the vehicle concept every time new product or model is released; we have incorporated JMAG in order to increase accuracy when specifications are selected and to further increase the number of development models.
We will report on case examples of magnetos (generators) and starter motors using JMAG.

Recently, requirement of low noise transformer have been increased as load noise was standardized in IEC in 2001. The major cause of transformer noise is core vibration, which is mainly due to the magnetostriction and the electromagnetic forces of electrical steel. This presentation introduces the developing 3D electromagnetic analysis technology to estimate the core noise of large transformers. First, we indicate the validation of efficiency of magnetostriction analysis function in JMAG, and the comparison of measured and calculated results of the natural vibration modes of a three-phase model core. Next, we’re planning to explain a perspective to improve the accuracy of the vibration analysis model for transformer cores considering the magnetostriction force.

It is an important issue to life evaluation of heating coil in high frequency induction heating. One cause of heating coil failure is thermal effect from inside and outside when heating.
In this study, at the first step of life evaluation of heating coil using CAE, we report evaluation result of thermal stress distribution in induction heating with JMAG, FLUENT, and ANSYS.

In custom BLDC motor design some customers request or require “non-standard” feedback methods. In these cases it is required to determine an acceptable location for the position of the sensors, based on magnetic field distribution.
This is a simple case study look at determining an acceptable sensor location. In this case study the position of linear hall sensors will be considered. Acceptable positioning will be determined by acceptably high output from the linear hall cell and acceptably low harmonic distortion in the wave form.

Supporting structure of turbine generator stator coil end require enough mechanical strength for Lorentz force due to the short circuit current.
Because large-sized rotating machines production and testing prototype is not easy, the design of supporting structure needs the evaluation by the coupling analysis of the magnetic field analysis and the stress analysis.
In this paper, we will introduce an example of the automated coupled magnetic-field and stress analysis by JMAG on a turbine generator stator coil end.

We perform coupled magnetic field and thermal analyses for the manufacturing process of HFW steel pipes. (HFW:High Frequency Electric Resistance Welding) The HFW steel pipes are produced through the method to weld the steel sheet edges using the joule heat, after producing the eddy current within the pipes caused by the magnetic field occurring in the work coils.
JMAG-Designer is used to perform the electromagnetic and heat transfer analyses for the HFW steel pipes, and We established FEM calculation model.
HFW steel pipes are heated while moving at a constant speed, an analysis method that can deal with heat transfer is required.
Conventional JMAG-Designer only supported the heat transfer in the straight direction. At the same time, special attention and care were required on generating mesh, such as making it finer, considering the heat transfer due to v-shaped welding point of HFW steel pipes.
In this presentation, we would like to report the improved JMAG-Designer which now supports heat transfer in any direction leading to accurate analysis.

Overheating in E-motor results in detrimental effects such as degradation of the insulation materials, magnet demagnetization, decreased motor efficiency and lifetime. Hence, it is important to find ways of optimizing performance and reliability of E-motor through effective thermal simulation and consequently reduce operating and maintenance costs. Modern thermal simulation techniques can be classified into two general methods, thermal circuit and FEM method. But because the 3D FEM method can more accurately predict and identify the temperatures of the critical points of the motor, it is more effectively than the thermal circuit method to evaluate the E-motor temperature rise. This paper describes a 3D thermal methodology for a permanent magnet synchronous motor by coupling 2D electromagnetic losses analysis with 3D thermal simulation. The energy sources are obtained from electromagnetic losses simulation by using JMAG. Coupling the loss results, the 3D nonlinear thermal model provided the detailed temperature distribution and rising results in E-motor assembly. Finally, a bench test was done to evaluate the FEM result, 3D thermal simulation results show good agreement with experimental results.

Litz wire is made of several strands of enameled wires that are twisted together.
In order to suppress the deterioration of properties caused by the skin effect due to high frequency currents, twisted groupings of wires continue to be used in a wide variety of fields.
For characteristics evaluation of wire material twisting condition, however, the complex twisted wire configuration makes construction of a 3D analysis model difficult; because of the difficulty in predicting the mesh size and calculation time, this creates complexities in proceeding with a detailed evaluation using the finite analysis method.
In this presentation, we will discuss effects of the twisted state on the characteristics, as well as the current state of analysis environments through JMAG’s Litz wire analysis.

To evaluate response characteristics of a solenoid valve, handling of attraction that works on the plunger, that is handling of electromagnetic force is important.
Electromagnetic force is determined by the magnetic properties consisting of a solenoid valve, but an analysis accounting for the influence of eddy current and the residual magnetization is necessary depending on the material characteristics or environment.
In this presentation, we will introduce the effect of eddy current and residual magnetization on the response properties through some case studies. This presentation also introduces some cases that analyzed response properties of the entire system including solenoid valves.

Comparison two types of interior permanent magnet vernior synchronous motors with surface permanent magnet synchronous motor and interior permanent magnet synchronous motor, using JMAG Express.

The output current of an external rotor synchronous permanent magnet generator (PMG) which is widely used in motorbikes and outboard engine is affected by the temperature of its magnets and windings. In conventional method, we usually assume the temperatures would be the same as measured data of similar generators when we calculate the output of PMG. However, as the size of PMG becomes smaller and output power density higher, the increased losses in PMG causes enlarged estimation error in temperatures that result in deterioration in the calculation accuracy of output. In this presentation, we propose a method for estimating the temperature of a winding in PMG using JMAG-Designer and STAR-CCM+.

Studies have been carried out on an eddy-current-rail-brake for railway vehicles, which uses linear motor technology and is called “linear-rail-brake.” This brake is capable of generating braking forces without contact. In addition, this method decreases the rise in rail temperature which is a problem in conventional rail brakes, and no excitation power supply is required by using dynamic braking.
A prototype of the linear-rail-brake was designed and built. Its electromagnetic characteristic was examined on a test bench. This article reports on design considerations of the linear-rail-brake and test results of the prototype, including calculated performances by JMAG.

In the magnetic field analysis of Solenoid actuator by FEM, it is necessary to deform or regenerate mesh of air gap according to position of plunger because the air gap length changes as plunger moves. In general, accuracy decreases if analyzed with deformed mesh and transient analysis with regenerated mesh is impossible because it is difficult to link the mesh information between steps. JMAG-Designer provides two methods for these problems. One is Patch Mesh method. The mesh at air gap is generated automatically using the information of mesh of step before. The other is method using FEM and BEM. Magnetic field at air gap is calculated without mesh by BEM and magnetic field at other area by FEM. Therefore it is unnecessary to generate mesh of the air gap. In this presentation, I introduce the knowledge gained from magnetic field analysis of Solenoid actuator with these methods.

The drive circuit is required in acquiring various characteristics of motors when benchmarking brushless motors, but it is difficult to prepare for a short amount of time.
For this reason, we used to evaluate only items in which electricity is not supplied.
However, JMAG-Express allows you to evaluate various characteristics of motors simply by entering motor parameters defined in the template, and this solves the problem mentioned above.
Furthermore, analysis in JMAG-Designer has made it possible for us to perform the benchmarking of highly-accurate motors, and this presentation will be introducing these case studies.

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In development of speeding technology of electromagnetic field analysis, the analysis which modeled the three-dimensional shape in detail in recent years is becoming possible.
For this presentation, the influence that the three-dimensional shape of the rotor exerts on an analysis will be confirmed through comparison of 2D/3D analysis in an induction motor.
And the effect of the analysis time reduction and a possibility of the future’s analysis by the application to three-dimensional analysis of speeding technology using HPC will be discussed.

To evaluate whether JMAG-Designer can predict responsiveness (switch time of valve) which is an important characteristic of portable pressure valves (hereonafter referred to as solenoid valves), our main product.
Responsiveness of solenoid valves can be substituted with changes in current occurring in the coil. We calculate the changes in current by using JMAG-Designer, then compare the calculated value with the actual measurement.

JMAG is being used at DENSO for design of e-motors for hybrid and electric vehicle powertrain applications. The features in JMAG-RT have proven to be a valuable part of the development of e-motors as well as the corresponding inverter and control software.
The export functions of stationary and dynamic e-motor models in JMAG-RT allow design engineers to conduct system or vehicle level simulations with MATLAB/Simulink in order to optimize the e-motor design for a given application.
Simulations in MiL-, SiL- and HiL-environments are possible with different objectives for example examining the thermal behavior of the e-motor or how active short-circuit may affect the vehicle dynamics.
Depending on objectives, stationary open-loop simulations, dynamic closed loop simulation as well as real-time highly dynamic simulations with spatial harmonics model are used in the different steps of the development cycle from requirements to testing and design validation.
With these features, the calibration and design validation time is reduced and customer support is enhanced by examining the requirements and the application of the component.

In Motor Design Optimization out of combinations from a wide-range of parameters, the most critical problem is evasion of the error such as intersection of each model line entity, because of each parameter depended mutually.
It is known as Input Parameterfs Constraint Conditions Problem in actual Optimization.
This paper presents that it is enabled multi-objective optimization for IPM Motor from among a wide-range of design space and complicated combinations of shape design parameters with evading above problem.

Designers such as those of motors vary in levels of skill depending on their technical knowledge and experience, and are also limited in time when it comes to being involved with magnetic field analysis of design.
We will be introducing case studies as we have developed a magnetic field design support system that is meant to efficiently proceed with design work that uses magnetic field analysis.

The advantage of GPU is the high theoretical performance value in terms of power consumption. On the other hand, automobile companies see priority in the efficiency of the software used in actual automobile development. JAMA is running wide-range GPU benchmark tests that are difficult to run independently within their framework. I would like to introduce these efforts including benchmark test results of electromagnetic field analysis software, JMAG.

The performance of electric steels can change dramatically after punching. Electric motors manufactured with the punched electric steels may then suffer from performance degrade. This indicates that, to conform motor performance to the design specifications, either such defects should be considered in the design or the degraded steel magnetic properties should be restored (for example, through annealing).
In this research, the effects of annealing on the recovery of the punching damage are first investigated.
Experimental work is carried out using test samples to observe the punching impact on electromagnetic properties and SRM performance. Two SRMs are then designed using JMAG and fabricated. These two SRMs are identical except that electrical steel in one of the motors is annealed while the other is not. The SRMs are tested using the same electronic driver and testing system to measure the output torque. The output torque of annealed motor is found to be higher than that of non-annealed motor under the same rotating speed.
This punching effect is then considered in the simulation of SRMs using JMAG. The magnetic properties (previously measured) in the damaged zones are input to JMAG for simulation of SRMs. The simulation results are compared with the experiments discussed above and they agree well. Finally, a discussion over the design of SRMs considering the damage zone is provided as a conclusion.

Nowadays, FEM electromagnetic field analysis is widely used to design and develop the electric machine. Moreover, large scale 3D analysis is becoming relatively common with the improvement of computer performance and massively parallel processing algorithm.
In this presentation, I will introduce about our approach to large scale analysis, and its necessity in design and development.

Nd-Fe-B sintered magnets with Dy diffusion technology are well-known for the coercive force distribution within one magnet, as well as its higher performance. Therefore, to optimize the motor design with Dy-diffusion magnets, it should be considered during the demagnetization analysis.
Because of this situation, JMAG-Designer Ver 13.1 added the new function which answers to the above consideration. On the other hand, Hitachi Metals had already introduced our self-developed analysis program.
In this report, at first we offer a practical example by both programs which do the demagnetization analysis of IPM motor applying Dy-diffusion magnets.
Then we describe the results and make some proposal to JMAG team as next step.

In DENSO CORPORATION, we evaluate injector and motor performance using JMAG. According to complication of model (shape, material property) and increasing calculation steps by co-simulation with controller and circuit , it is becoming impossible to calculate in a realistic period.
So we attacked to develop HPC (High Performance Computing) method in the case of 3D-Motor model with JSOL Corporation. In the conventional JMAG, 8-core parallels computing was maximum. So we developed 128-core parallels computing using new JMAG version. As the result, the parallelization efficiency of 64-core parallels is the maximum in this model.

Brush motor magnetic circuit is constructed with three-dimensional. Due to time constraint, difficulty occurs to simulate all factors by three-dimensional model. Reduction of necessary simulation time depends on how to implement three-dimensional model simulation on two-dimensional. This presentation describes proper use of three and two dimensional simulation, and JMAG adapting method for brush motor magnetic simulation.

Reactor use is increasing with the popularization of the hybrid car and the power conditioner.
Recently with the increased use in the high-frequency region, loss reduction has been a theme of research.
However, factor analysis of loss with prototype measurement is not an easy task. As a result, high-precision loss estimates with CAE are becoming increasingly important.
To improve accuracy of reactor loss analysis, we will discuss the advantages of adopting the high-precision hysteresis loss analysis function of JMAG V13.

We established the measurement technique of magnetic flux density on permanent magnet surfaces when IPM motor operates using small and thin 2 type sensors.
This technique was applied to the HV motor for driving. The frequency component and generating area of the eddy current loss were clarified.

Recently, high power density and high efficiency of power converters are required. To reduce losses occurring in magnetic components, amorphous cut cores and nanocrystalline cut cores have been proposed.
For inductor applications, an air gap has to be inserted into the magnetic circuit to avoid saturation. However, when an air gap is inserted, fringing flux leaks out of the air gap. We use JMAG to clarify the behavior of the fringing flux.
In this report, we will introduce a modeling method of the cut core inductor and analysis result of the iron loss. The fringing flux induces in-plane eddy current and concentrates on the surface of the core. As a result, additional losses called gap loss occur. We introduce methods to reduce the gap loss.

We will introduce a drive motor for one-motor SPORT HYBRID system i-DCD, which is optimized for the compact car.
The i-DCD system is equipped in the new FIT3 model, which uses 7-speed DCT (Dual Clutch Transmission) with the built-in motor, and the engine can be disconnected and motor drive engaged in response to driving conditions. The i-DCD system improved fuel efficiency by 18% at the JC08 mode in comparison to the IMA (Integrated Motor Assist) system, which directly links the motor to the engine crank axis.
The motor equipped in the DCT has been reduced in size to fit into the transmission of a compact car. Also, to fulfill system requirements, highly-efficient, high-power motor have been developed using magnetic field analysis technology.
This time, we will go into the details of the applied technology put into motor development and the performance of the motor.

The demand to make power components in vehicles even smaller brings about key design challenges, such as iron loss reduction and heat dissipation improvements in order to address resulting heating issues.
Utilizing litz wires are effective way to reduce coil loss, but coils exceeding 100 wires are nearly impossible to model and analyze. Realistically, transformer study functions are utilized, which offer approximately the same results as stranded wires.
In this presentation, we will discuss evaluating coil resistance when design parameters such as gap length are assigned.

Many discussions took place at the Users Conference where users shared both compliments and constructive criticisms regarding JMAG. We would like to make full use of these suggestions in developing our next series of products. Thank you for your support.