CASE Studies |
- Basic characteristic analysis
- N-T characteristic analysis / T-I characteristic analysis
- Thrust force analysis
- Cogging analysis
- Braking torque analysis
- Pull-In/Pull-Out torques analysis
- Detent torque and stiffness torque analysis<
- Efficiency analysis
- Starting performance analysis
- Torque ripple analysis
- Attractive force analysis
- Inductance analysis
- Iron loss analysis /Loss analysis
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- Eddy current analysis
- Magnetization analysis
- Demagnetization analysis
- Eccentricity analysis
- Response characteristic analysis
- Positioning control analysis
- Operating time analysis
- Centrifugal force analysis
- Sound pressure analysis
- Thermal analysis
- Temperature distribution analysis
- Head field analysis
- Output power analysis
- Capacitance anlysis
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| Thrust Force Analysis of a Coreless Linear Motor
Coreless linear motors are used for linear motor stages and electronic packaging machines. Generally, the thrust force of a coreless linear motor is smaller than that of an iron core linear motor. Since a coreless linear motor has no cogging, its thrust force variation is much less than an iron core linear motor. This note presents the use of magnetic field analysis to obtain the thrust force of a coreless linear motor.
Module:TR |
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| Analysis of Static Thrust of a Voice Coil Motor
Coreless linear actuators are used for the head drive of electronic packaging machines and precision stages, both of which require high accuracy positioning. Static thrust has a great effect on accurate positioning, since it varies with the translation position of an actuator. Also, static thrust varies with the amount of current, so it is important to obtain the static thrust at each supply current from the analysis. This note presents the use of magnetic field analysis to obtain static thrust characteristics of a voice coil motor at different translation positions and different supply currents.
Module:TR |
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| Analysis of a Three Phase Induction Motor for the Speed-Torque Curve
In the induction motor, current is induced in the rotor cage by the rotating magnetic field of stator coils, causing the rotor to turn. Induction motors are widely used from industrial machines to home appliances since they are small, light, affordable, and maintenance-free. Analyzing the current induced in the rotor bars is important since the induced current essentially determines the performance of the induction motor. This note presents the use of magnetic field analysis to obtain the current density distribution and the speed-torque curve of a three-phase induction motor.
Module:DP |
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| Analysis of a Permanent Magnet Brush Motor
A brush motor rotates when the brushes and commutator alternate the direction of the current passing through the armature conductors.Torque is proportional to the product of the current and the torque constant. Therefore, to generate a larger torque with the same current, the torque constant needs to be increased.However, increasing the torque constant will reduce the rotation speed, so it is important to understand the torque characteristics of the motor.This note presents a case study of a 2-pole 3-slot small brush motor with regard to its Speed-Torque curve and Torque-Current curve.
Module:DP |
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| Analysis of a Three Phase Induction Motor
Induction motors are widely used in many industries. The performance of an induction motor is significantly affected by the current induced in the cages due to its rotation mechanisms. This case study shows the current distribution in the secondary conductor and the N-T (number of rotation versus torque) characteristic obtained using JMAG.
Module:DP
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| Analysis of a Hybrid Stepper Motor
A hybrid stepper motor has a cylindrical magnet, magnetized in the stack length direction that is sandwiched in the rotor with serrated salient poles. This case study shows the detent torque as a torque when the stator coil is unexcited, and stiffness torque as a static torque.
Module:TR
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| Magnetic Field Analysis of a Speed Sensor
Magnetic sensors have been used as automotive sensors.It is important that the accuracy, sensitivity and the responsiveness of the sensors must be ensured while the car is operating.The sensor performance improves if magnetic core is placed close to the wheel. However, it is also important to have adequate distance between them to avoid some dirt or foreign objects from being stuck.This note presents the use of magnetic field analysis to evaluate the voltage signal that varies with distance.
Module:TR |
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| Analysis of a Transformer
A transformer is an electrical device that converts the voltage level of alternating-current power using electromagnetic induction.
Although the secondary voltage is required to be constant regardless of the load, it varies with amount of the load and the power factor. To ensure the access to constant voltage, the size of the voltage variation is one of the important output characteristics of the transformer.
Maintaining the balanced state is also the critical issue, since the imbalanced voltage and current of each phase may cause the trouble to the device as well as the temperature rise.
This note presents the use of magnetic field analysis to evaluate the changes in the secondary voltage caused by the load variation of a low frequency transformer.
Module:FQ |
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| Analysis of a Spindle Motor
Spindle motors with permanent magnets can be small-sized and produce high torque. To improve the general performance of the spindle motor, the effects of the 3D geometry and magnetic saturation should be included in the analysis. This note shows the Speed-Torque curve and Torque-Current curve of a spindle motor obtained from an analysis.
Module:TR |
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| Analysis of Torque Characteristics of a Cage Induction Motor
Induction motors have been widely used in general industries since they have simple structure, and are affordable, robust and highly efficient. When an induction motor rotates at synchronous speed, no torque is produced. However, when it has a proper slip, the maximum torque can be obtained. In a cage induction motor, when current flows in the cage, the loss is caused. So, the duration of rotation needs to be controlled depending on the amount of heat generation. This note presents the use of magnetic field analysis to obtain the torque characteristics of a cage induction motor.
Module:FQ |
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| Analysis of a Three Phase Induction Motor for the Speed-Torque Curve
In the induction motor, current is induced in the rotor cage by the rotating magnetic field of stator coils, causing the rotor to turn. Induction motors are widely used from industrial machines to home appliances since they are small, light, affordable, and maintenance-free. Analyzing the current induced in the rotor bars is important since the induced current essentially determines the performance of the induction motor. This note presents the use of magnetic field analysis to obtain the current density distribution and the speed-torque curve of a three-phase induction motor.
Module:DP |
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| Analysis of a Permanent Magnet Brush Motor
A brush motor rotates when the brushes and commutator alternate the direction of the current passing through the armature conductors.Torque is proportional to the product of the current and the torque constant. Therefore, to generate a larger torque with the same current, the torque constant needs to be increased.However, increasing the torque constant will reduce the rotation speed, so it is important to understand the torque characteristics of the motor.This note presents a case study of a 2-pole 3-slot small brush motor with regard to its Speed-Torque curve and Torque-Current curve.
Module:DP |
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| Analysis of a Three Phase Induction Motor
Induction motors are widely used in many industries. The performance of an induction motor is significantly affected by the current induced in the cages due to its rotation mechanisms. This case study shows the current distribution in the secondary conductor and the N-T (number of rotation versus torque) characteristic obtained using JMAG.
Module:DP |
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| Analysis of a Spindle Motor
Spindle motors with permanent magnets can be small-sized and produce high torque. To improve the general performance of the spindle motor, the effects of the 3D geometry and magnetic saturation should be included in the analysis. This note shows the Speed-Torque curve and Torque-Current curve of a spindle motor obtained from an analysis.
Module:TR |
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| Thrust Force Analysis of a Coreless Linear Motor
Coreless linear motors are used for linear motor stages and electronic packaging machines. Generally, the thrust force of a coreless linear motor is smaller than that of an iron core linear motor. Since a coreless linear motor has no cogging, its thrust force variation is much less than an iron core linear motor. This note presents the use of magnetic field analysis to obtain the thrust force of a coreless linear motor.
Module:TR |
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| Analysis of Static Thrust of a Voice Coil Motor
Coreless linear actuators are used for the head drive of electronic packaging machines and precision stages, both of which require high accuracy positioning. Static thrust has a great effect on accurate positioning, since it varies with the translation position of an actuator. Also, static thrust varies with the amount of current, so it is important to obtain the static thrust at each supply current from the analysis. This note presents the use of magnetic field analysis to obtain static thrust characteristics of a voice coil motor at different translation positions and different supply currents.
Module:TR |
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| Cogging Analysis of a Moving Coil Linear Motor
Linear motors are used for machine tools, carrier devices and so forth, so it is very important for them to move smoothly and response quickly. To do so, cogging needs to be reduced, since cogging causes the variation in thrust force and speed. One method to reduce cogging is to skew the magnet. This note presents the use of magnetic field analysis to obtain the magnetic flux density distribution and cogging of a moving coil linear motor with a skewed magnet.
Module:TR |
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| Cogging Torque Analysis of an SPM Motor
Cogging torque is produced by the interaction between the permanent magnet and the stator core when the rotor rotates with no current flow.
The cogging torque prevents the smooth rotation of the rotor, which may lead to vibration and noise. So the evaluation of the accurate cogging torque can be an important issue.
The period of the cogging torque is determined by the number of poles and slots, so they are significant factors for evaluating cogging torque.
This note presents the use of magnetic field analysis for evaluating the cogging torque of an 8-pole, 9-slot SPM motor, which has relatively small period of the cogging torque.
Module:DP
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| Cogging Torque Analysis of an SPM Motor with a Skewed Stator
For motors, there is a need of reducing vibration and noise. Cogging torque is one cause of vibration and noise, so reducing cogging torque is an important issue. And one way of reducing the cogging torque is to skew either the rotor or the stator. This note presents the use of magnetic field analysis to evaluate the cogging torque of an SPM motor with the skewed stator.
Module:TR
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| Cogging Torque Analysis of an SPM Motor with a Step Skewed Magnet
For motors, reducing vibration and noise is a critical issue. Cogging torque is a major cause of vibration and noise. The cogging torque in an SPM motor is strongly affected by the magnet. One solution to reduce the cogging torque is to use a step-skewed magnet. This note presents the use of magnetic field analysis to evaluate the cogging torque of an SPM motor with a step-skewed magnet.
Module:TR |
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| Analysis of the Cogging of a Permanent Magnet Linear Motor
Linear motors have been used in carrying devices and tooling machines. While the key issue is to increase the thrust force, reducing variations in thrust force and magnetic attraction are also required. In this case study, the cogging which causes variations in thrust force is calculated, and then the thrust force is evaluated.
Module:TR
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| Braking Torque Analysis of an Electromagnetic Brake
An electromagnetic brake is a device used as an auxiliary brake for heavy vehicles such as trucks and buses, which decelerates a propeller shaft by directly applying the braking force. When the magnetic field generated by the stator coils interacts with the rotor, eddy currents flow in the rotor, producing a braking torque. This note presents the use of magnetic field analysis to evaluate the braking torque of the brake at different rotation speeds.
Module:TR
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| Analysis of PM Stepper Motor's Pull-In / Pull-Out Torques using Control Simulator and JMAG-RT System
Stepper motors are commonly used for positioning in printers or digital cameras.Pull-in and pull-out torques are important characteristics for evaluating a stepper motor, and hence, need to be investigated before designing the motor. In JMAG, it is possible to calculate these characteristics using 3D transient response analysis, however, it may take too much time.So, JMAG-RT system is used to create RT motor model, which is used as a reference for a circuit / control simulator to obtain pull-in and pull-out torques. This note presents how to obtain pull-in and pull-out torques at each pulse rate in the case of a stepper motor with bifilar winding / unipolar drive and in the case with monofilament winding / bipolar drive.
Module:TR,RT |
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| Analysis of a Hybrid Stepper Motor
A hybrid stepper motor has a cylindrical magnet, magnetized in the stack length direction that is sandwiched in the rotor with serrated salient poles. This case study shows the detent torque as a torque when the stator coil is unexcited, and stiffness torque as a static torque.
Module:TR |
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| Efficiency Analysis of an IPM Motor
IPM motors use not only magnetic torque produced by a permanent magnet and the rotating magnetic field but also reluctance torque produced by the inductance difference between the d-axis and the q-axis. So, they are highly efficient motor with high torque. The current phase angle ß, at which torque and efficiency are maximized, varies with rotation speed and torque. So, the current phase angle ß needs to be taken into account for designing high efficient motor. This note presents the use of magnetic field analysis to obtain the efficiency of an IPM motor at each current phase with the rotation speed of 1800 rpm and the current amplitude of 4.0 Ampere when the motor is driven by sinusoidal current.
Module:DP,LS |
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