Cut-planes
 | 152 - Electromagnetic Force Analysis of Short-circuited Power Transformer Windings
| Module:FQ | 2011-07-12 | Electromagnetic force is produced by the current on the windings of the transformer. The windings can be deformed or damaged by the powerful electromagnetic force produced when there is a short-circuit current flowing. Therefore, confirming where the various forces are acting on the windings using analyses is vital.
This note presents the use of a magnetic field analysis to obtain the Lorentz force density and electromagnetic force produced in the windings when short-circuited by changing the position of the windings to display the effects of the primary and secondary windings.
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  | 150 - Electrodynamic Repulsion Force Analysis of a Switching Gear
| Module:TR | 2011-02-28 | The large capacity switching gear indicated in the figure produces electrodynamic repulsion force by the current flowing in the contacts during excitation. Therefore, the contact stress needs to be larger than the electrodynamic repulsion force produced by the maximum excitation current.
This example presents the use of a magnetic field analysis to obtain the electrodynamic repulsion force of a switching gear from the Lorentz force when a short-circuit current of 100 kA is applied.
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 | 149 - Analysis of Magnetic Blowout Force Acting on the Arc of a Switching Gear
| Module:TR | 2011-02-28 | Metal vapor is produced from the contacts of a switching gear during cutoff and a plasma arc forms. The structure of the contact rings is innovated to produce a magnetic field that expands the arc and prevents vacuum deposition caused by the arc. The arc expands by the Lorentz force that is produced.
This example presents the use of a magnetic field analysis to obtain the current density and Lorentz force of the switching gear and the force expanding the arc.
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 | 102 - Magnetic Field Analysis of a Magnetic Sensor
| Module:ST | 2013-02-28 | With recent improvements in the functionality of electric devices and home appliances, magnetic sensors are being used more for contactless sensing of whether device doors, etc. are open or closed. An open/closed switch using a magnetic sensor switches between open and closed by sensing distance according to the size of the magnets' magnetic field. At the design stage, it is necessary to evaluate magnet type and position, sensor sensitivity, and other issues.
Magnetic field analysis simulation using the finite element (FEM) method is effective for accounting for differences in magnetic field strength due to three-dimensional positioning and interference from other magnetic parts.
This Application Note presents how to obtain the magnetic flux density distribution at points in the horizontal and vertical directions away from the magnet.
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 | 83 - Magnetic Shielding Analysis of an Induction Furnace
| Module:FQ | 2013-02-28 | An induction furnace is an apparatus that uses high-frequency induction heating to melt metal. Running current through the coil surrounding the crucible starts electromagnetic induction phenomena, which generate current in the metal in the crucible. This current produces joule losses in the metal, which are used to heat and melt it. Magnetic yokes are arranged around the coil. The yokes are used as strong components that prevent the Lorentz force generated by the coil from damaging and deforming it. The magnetic yokes also reduce the leakage flux that flows out of the appliance, preventing unintended heating in surrounding structures. Keeping the amount of material used in the magnetic yokes to a minimum makes it possible to reduce the cost of the apparatus.
To understand the magnetic flux that spreads from the induction furnace, it is necessary to use the eddy current distribution and magnetic flux flow in the metal in the crucible, as well as the concentrations in magnetic flux caused by the positions of the yokes.
This Application Note displays magnetic flux density distribution to evaluate the differences in magnetic flux with and without yokes.
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 | 53 - Magnetic Shielding Analysis of a Shield Room
| Module:FQ | 2013-01-28 | Shield rooms are meant to protect precision equipment from the influence of external magnetic fields, so they have to be an enclosed space that implements special processing in the walls that blocks magnetic flux. The effects of external magnetic fields inside the shield room depend on how they are generated, where the precision equipment is located, and the position of the shield room's opening and supply cable.
A magnetic field analysis using the finite element method is necessary to perform an evaluation that deals with three dimensional and temporal variations to figure out how magnetic flux enters the shield room when several external magnetic fields have been applied.
This Application Note explains how to handle the magnetic shielding phenomena used by the shield room when an external magnetic field is applied, and from there how to confirm the magnetic flux density distribution.
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 | 51 - High-Frequency Induction Heating Analysis of a Gear
| Module:FQ,HT | 2013-01-28 | Gears are created in such a way that the surfaces of their teeth are hard in order to resist the wear and tear that occurs when they come into contact with the teeth of other gears. However, this has to be accomplished while maintaining the gear's overall toughness. By using high-frequency induction heating, which is a type of surface hardening method, the teeth are heated rapidly on only their surface by a high frequency power source. This process also has many other benefits, such as providing a clean working environment because it uses electrical equipment, being very efficient, and providing uniform results for each product. This is why it is being aggressively implemented in the field. On the other hand, there are several factors that need to be studied in order to heat the gear's surface uniformly, such as how to adjust the heating coil's geometry, arrangement, current frequency and size.
The eddy currents generated by high-frequency varying magnetic fields are uneven in the tooth surface, so the material properties change a great deal as the temperature rises. In order to handle the detailed phenomena, it is necessary to calculate the heat generation amount in a numerical analysis based on the finite element method (FEM).
This Application Note shows how to create a numerical analysis model when obtaining the optimum coil geometry and current conditions (power supply frequency and current value), analyze the elevated temperature process, and evaluate whether or not the model fulfills the target temperature distribution.
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 | 50 - High-Frequency Induction Heating Analysis of a Steel Wire (Translational Induction Hardening)
| Module:FQ,HT | 2012-07-31 | Steel wires are made to be resistant to wear and tear. This is accomplished by giving them a certain degree of flexibility by maintaining their inner toughness while increasing the hardness of their surfaces. By using high-frequency induction heating, which is a type of surface hardening method, the steel wire is heated rapidly on only its surface by a high frequency power source. This process also has many other benefits, such as providing a clean working environment because it uses electrical equipment, being very efficient, and providing uniform results for each product. This is why it is being aggressively implemented in the field. On the other hand, when the heating target is a long steel wire, it is heated rapidly while passing through the heating coil. For this reason, there are several factors that need to be studied when assigning a heating amount to correspond to the speed at which the wire passes through the coil. Examples of these are: the arrangement of the heating coils so that it can fulfill the necessary heating amount, and how to adjust the current's frequency and size.
This Application Note presents a simulation of the heating conditions of a sufficiently long steel wire that passes through a heating coil. The eddy currents produced from the high frequency's varying magnetic fields are uneven on the steel wire's surface, so its material properties change due to increases in temperature. This is why it is necessary to approximate the amount of heat generated in a numerical analysis based on the finite element method (FEM) in order to handle the detailed phenomena.
This Application Note explains how to create a numerical analysis model when obtaining the optimum coil geometry, current conditions (power supply frequency, current value), and movement speed. It also shows how to evaluate whether the model fulfills the target heating speed by analyzing the elevated temperature process.
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 | 49 - High-Frequency Induction Heating Analysis of a Steel Sheet | Module:FQ,HT | 2012-08-31 | The rolling process of steel sheets changes the strength and properties of the product, so heat treatment is used. High frequency induction heating is a type of heat treatment that uses a high frequency power source to produce rapid heating, allowing the equipment on the production line to be smaller. It also has a multitude of benefits, such as being highly efficient and providing a clean working environment. When the object being heated is a long steel sheet, this process heats it quickly while sending it through a heating coil. For this reason, there are several factors that need to be studied when assigning a heating amount to correspond to the speed at which the sheet passes through the coil. Examples of these are: the arrangement of the heating coil so that it can fulfill the necessary heating amount, and how to adjust the current's frequency and size.
This Application Note presents a simulation of the heating conditions of a sufficiently long steel sheet that passes through a heating coil. The eddy currents produced from the high frequency's varying magnetic fields are uneven on the steel sheet's surface, so its material properties change due to increases in temperature. This is why it is necessary to approximate the amount of heat generated in a numerical analysis based on the finite element method (FEM) in order to handle the detailed phenomena.
This Application Note explains how to create a numerical analysis model when obtaining the optimum coil geometry, current conditions (power supply frequency, current value), and movement speed. It also shows how to evaluate whether the model fulfills the target heating speed by analyzing the elevated temperature process.
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 | 16 - Analysis of a Hybrid Stepper Motor
| Module:TR | 2013-01-28 | Hybrid stepper motors are used as actuators for equipment where position detection accuracy is required, such as the joints of robots or rotary tables for machine tools. The rotor has a construction that sandwiches a magnet that is magnetized in the axial direction between two rotor cores that have serrated teeth to create salient poles, and the tips of the stator core's teeth are shaped like gears as well. The rotation resolution is determined by the number of gears in the rotor and the number of phases in the drive coil, so the number of gears is set to rather large numbers like 50 and 100 to raise the angle resolution. The most important characteristics for a stepper motor are the controllability, the detent torque, which is a non-excitation holding torque, and the stiffness torque, which is an excitation holding torque, and not the motor's output.
The two-plated rotor core of a stepper motor has an N pole on one side and an S pole on the other, so a multipole magnet is achieved by deviating the saliency of the gear condition by 1/2 pitch. Consequently, the magnetic circuit is 3D. There are also times when the division pitch geometry of the teeth is complicated, so it is necessary to carry out a 3D electromagnetic field analysis using the finite element method (FEM) to proceed with an accurate preliminary study.
This Application Note describes how the detent torque and stiffness torque can be calculated for a hybrid stepper motor.
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