‑‑‑‑ White Paper
COSMOSEMS Analysis Types
C o n t e n t s Why Electrostatic Analysis?
1-3
Why Electric Conduction Analysis?
4-5
Why Magnetostatic Analysis?
6-8
Why AC Magnetic Analysis? Why Transient Magnetic Analysis?
8-10
11-12
COSMOS
®
SolidWorks Corporation
Motion simulation provides complete, quantitative information about the kinematics - including position, velocity, and acceleration, and the dynamics - including joint reactions, inertial forces, and power requirements, of all the components of a moving mechanism.
introduction
Electric discharge showing the lightning-like plasma filaments from a Tesla coil.
Why Electrostatis Analysis? •
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Avoid rapid reduction in the resistance of an electrical insulator that can lead to a spark jumping around or through the insulator or the so called dielectric breakdown. This phenomenon is common in high voltage applications. Avoid the ionization of a fluid surrounding a conductor, or the so called corona, in some applications such as power transmission equipments, transformers, capacitors, electric motors and generators. Produce corona in some other applications such as the manufacturing of ozone, scrubbing particles from air in air-conditioning systems, nitrogen laser, removing the unwanted electric charges from the surface of aircraft in flight, and electrostatic copying. Evaluate complex electrode structures. Evaluate the electric field strength. Avoid interference in electronic devices and systems. Reduce electrostatic discharge.
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Electric field, voltage, capacitance, dielectric breakdown, corona, electric force, charged particle trajectory, electrodes, printed circuit board, interference, spark plugs, MEMS.
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Examples
A lightning arrester, or lightning protector, is a metal strip or rod, usually of copper or similar conductive material, used as part of lightning safety to protect tall or isolated structures (such as the roof of a building or the mast of a vessel) from lightning damage. The Electrostatic module can be used to optimize the shape and material for such device.
Lighting arrester
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A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed aerosol gasoline by means of an electric spark. Spark plugs have an insulated center electrode which is connected by a heavily insulated wire to an ignition coil or magneto circuit on the outside, forming, with a grounded terminal on the base of the plug, a spark gap inside the cylinder. The Electrostatic module can be used to optimize the shape and size of the electrodes. It can also be used to choose an insulator that can withstand a voltage difference of up to 60000V.
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With the introduction of PDMWorks Enterprise software, SolidWorks Corporation has completely changed the PDM paradigm by creating a simple, efficient, affordable solution that meets the PDM needs of any mainstream product development organization.
A bushing is a component that insulates a high voltage conductor passing through a metal enclosure. Bushings appear on switchgear, transformers, circuit breakers and other high voltage equipment. Bushings sometimes fail due to partial discharge degradation or dielectric breakdown in the insulation due to high voltage stress. The Electrostatic module can be used to avoid such a breakdown. It can also be used to efficiently grade the voltage down from high power voltage conductors in transformers.
Bushing
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Typically used in microwave ovens, a magnetron is a tube that utilizes electrical and magnetic fields in order to create an intense heat output. A magnetron tube has a filament in the center which heats up when it is exposed to a slight amount of voltage or energy. The filament gives off electrons as it becomes hotter. These electrons move outward in search of positive anodes, or electrodes, but they come in contact with a negative
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Spark plugs
cosmosems analysis types
A magnetron
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Motion simulation conducts interference checks in real time, and provides the exact spatial and time positions of all mechanism components as well as the exact interfering volumes.
magnetic field along the way. The negative magnetic field within the magnetron repels the electrons. As a result, they become stuck in one area and begin rotating in circles. This creates more heat, as well as a supply of energy strong and hot enough to quickly cook an item. The Electrostatic module can be used to adjust the electric field in the cavity so that the electrons do not reach the anode and stay in a cyclic trajectory.
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An RF-MEMS switch is made up of a thin metal cantilever, air bridge, diaphragm, or some other structure electrically configured in series or parallel with an RF transmission line and designed to open the line or shunt it to ground upon actuation of the switch. Such switches have displayed excellent RF characteristics. However, their design is sophisticated due their very small size. The Electrostatic module would help determining the impact of device geometries on switch control voltage and contact force.
An RF-MEMS switch
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The Universal Serial Bus, or simply a USB, is a serial bus standard to interface devices, founded in 1996. It is currently widely used among PCs, Apple Macintosh and many other devices. It is a 4-pin connector, surrounded by a shield. Recently, he USB Implementers Forum, Inc. (USB-IF) announced the completion of the Micro-USB specification, a new connector technology that will replace many of the Mini-series plugs and receptacles currently used in portable products. This USB-IF connector specification was developed to support the growing miniaturization trend for portable devices, as well as the continued adoption of USB in mobile phones. The Electrostatic module can be used to compute the capacitance matrix of the four pins of the connector. Hence help in the miniaturization process.
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A USB connector
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Why Electric Conduction Analysis? •
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Protect electric and electronics equipment from over current by designing the appropriate fuse. Measure the current flowing though an electric circuit by designing the appropriate shunt. Protect electric and electronics equipment from over voltage condition by designing the appropriate crowbar circuit that uses both fuses and shunts. Compute the resistance of any arbitrary shaped resistor. Compute the electric current density in arbitrary shaped conductor. Evaluate the electric field strength and voltage distribution.
Keywords Electric field, voltage, resistance, fuse, crowbar, electric cable, electrodes, surge protector, shunt. With the introduction of PDMWorks Enterprise software, SolidWorks Corporation has completely changed the PDM paradigm by creating a simple, efficient, affordable solution that meets the PDM needs of any mainstream product development organization.
Examples
The main job of a fuse is to protect the electric and electronic circuits. Fuses should be sized and located to protect the wire they are connected to. If a device like your car radio suddenly draws enough current to blow the fuse, the radio is probably already toast. The fuse is there to protect the wire, which would be much easier to replace than the radio. Fuses come in hundreds of shapes and specifications but they are all based on the principle of melting at a high current level. The Electric Conduction module can help in determining the current distribution and the hot spots in a fuse.
Plug-in type fuses
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In electronics, a shunt is a device which allows electrical current to pass around another point in the circuit. For example, in miniature Christmas lights, which are wired in series. When the filament burns out in one of the incandescent light bulbs, the electrical resistance becomes very high. The much higher voltage that this creates (equal to the full line voltage rather than the normal voltage divider level) causes the shunt to short out
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Shunt Resistor of kWh Electricity Meter
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High voltage shunt capacitor
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Replicating portions of the PDMWorks Network Vault to different servers or providing secure web access to design data at the user level enables product development organizations to support collaboration anywhere in the world.
(becoming an anti fuse) and become part of the circuit, again allowing electricity to pass and the set to light. A shunt can also be used to measure current. In this case a resistor of accurately-known resistance, the shunt, is placed in series so that all the current to be measured will flow through it. Since the resistance is known, by measuring the voltage drop across it, one can calculate the current flowing. The Electric Conduction module can help in selecting the proper shunt material and voltage.
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Resistors are commonly used in electrical circuits. They play diverse roles. For instance, a resistor can be used to create a known voltage-to- current ratio in an electric circuit. If the current in a circuit is known, then a resistor can be used to create a known potential difference proportional to that current. Conversely, if the potential difference between two points in a circuit is known, a resistor can be used to create a known current proportional to that difference. It can also be used as a current-limiting device. By placing a resistor in series with another component, such as a light-emitting diode, the current through that component is reduced to a known safe value. Take another example: a series resistor can be used for speed regulation of DC motors, such as used on locomotives and train sets. A resistor can also be used in heating elements. Regardless of the role a resistor plays, knowing its resistance value is crucial. The Electric Conduction module can help in exactly doing that. That is, it computes the resistance for any arbitrary-shaped resistor.
Resistors
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Electrical cables are the building blocks of the electrical and electronic circuits. No matter what the application might be, knowing the current density distribution inside a cable is essential. The Electric Conduction module can help in exactly doing that.
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Electrical cables
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Why Magnetostatic Analysis? •
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To understand how motion simulation and FEA work together in mechanism simulation, it helps to understand the fundamental assumptions on which each tool is based.
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Avoid saturation in magnetic devices. Magnetic saturation is a limitation occurring in ferromagnetic cores. Initially, as current is increased the flux increases in proportion to it. At some point, however, further increases in current lead to progressively smaller increases in flux. Eventually, the core can make no further contribution to flux growth and any increase thereafter is limited to that provided by air - perhaps three orders of magnitude smaller. Minimize the cogging torque. The cogging torque of electrical motors is the torque due to the interaction between the permanent magnets and the stator slots of a Permanent Magnet (PM) machine. Also termed as detent or ‘no-current’ torque, it is an undesirable component for the operation of such a motor. It is especially prominent at lower speeds, with the symptom of jerkiness. Lower cost and weight of magnetic devices by trimming excess material from ferromagnetic cores. Optimize the torque in motors while maintaining the driving current to a minimum. Avoid sparking and thus minimize brush wear and electric noise in motors. Optimize the force for linear solenoids and the torque for rotary solenoids without overheating the winding. Evaluate complex coil structures. Evaluate a multitude of permanent magnet configurations.
Keywords Magnetic field, magnetic flux, flux density, inductance, coil, permanent magnets, ferromagnetic material, motor, solenoid, flux leakage, force, torque, saturation, magnetic circuit, flux linkage, B-H curve. Examples
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Most magnetic devices degrade significantly after saturation. Take an example of a magnetic shielding apparatus, (also known as magnetic shields, magnetic screens and EMI shielding), that prevents magnetic fields from reaching areas where they would cause magnetic interference. Magnetic shielding is used around either the source of interference, to prevent electromagnetic radiation from leaving a device; or more typically, around a sensitive device, to prevent the electromagnetic interference from disrupting normal operations. If the ferromagnetic material of the shield reaches saturation, it would act
Magnetic recording
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EMI shielding gasket
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Because the system is fully configurable, PDMWorks Enterprise provides the ability to automate an organization’s workflow and approval processes today and to adapt and keep pace as procedures evolve over time.
Rotary solenoids
like air and thus defeats the purpose of shielding. A recording head looses the stored information if the magnetic media reach saturation. Similarly, a plunger in a solenoid would longer pull its load if its ferromagnetic material reaches saturation. The Magnetostatic module can be instrumental in determining the saturation level in magnetic devices.
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Cogging torque is produced by the magnetic attraction between the rotor mounted permanent magnets and the stator. It is an undesired effect that contributes to the output ripple, vibration, and noise in the machine. Cogging torque minimization techniques have been extensively researched. These techniques include variations in the magnet remanence, magnet arc length, single and double pole pair offset, magnetization, eccentricity, stator slot opening, stator tooth shoulder width, yoke notch radii, skew, and overhang. The Magnetostatic module can be the ideal workbench for experimenting with different techniques.
Wind turbine generator where cogging torque could be significant
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In a solenoid design, a cylinder guides the plunger travel. If this cylinder is very short, there is little area for flux transfer and the force available is reduced. If the cylinder is too long, much of the flux will bypass the plunger. This reduces the force available, and adds to the inductance of the solenoid. To solve this problem, a parametric analysis can readily be performed to find the optimum length using the Magnetostatic module. Electromechanical devices such as solenoids, actuators, motors,
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Hyundai starter
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Linear solenoids
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and alternators are widely used in our daily life. Thus, there is a huge market for these devices. Never the less, such market is very competitive. In addition, there is a general trend towards miniaturization of many of the electromechanical devices. These two criteria have pushed designers and manufacturers to search for ways to cut cost and reduce weight while maintaining performance. The Magnetostatic module can be the ideal tool to achieve those goals.
Step motors
Brush motors
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Electric motors and generators consume over 60% of all electricity produced and on the average, are operating at less than optimum efficiency or performance. Considering these prodigious facts and today’s acute sensitivity to energy conservation, new electric motor technologies are emerging that advertise the ultimate in efficiency and performance. Fortunately, they are all based on the same motor physics; do not let some one tell you differently! COSMOSEMS is in the crux of motor physics.
DC Brushless motors
Why AC Magnetic Analysis? PDMWorks Enterprise facilitates design reuse by enabling manufacturers to classify, organize, and group design information for quick search and retrieval.
Minimize eddy current losses and preserve efficiency of many devices that use changing magnetic fields such as iron core transformers and alternating current motors. • Optimize the Non-Destructive Testing (NDT) and Non-Destructive Evaluation (NDE) equipment to better detect cracks and flaws in metallic parts. • Optimize the coils design of metal detector to better detect metallic objects such mines, weapons, treasures, etc. • Minimize the flux leakage and leakage inductance in transformers. • Minimize the skin effect in solid coils. • Optimize the force for linear solenoids and the torque for rotary solenoids without overheating the winding. Keywords •
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Eddy current, skin effect, NDT, NDE, magnetic field, magnetic flux, flux density, inductance, coil, , ferromagnetic material, motor, solenoid, flux leakage, force, torque, magnetic circuit, flux linkage, Eddy current losses, induction heating. Examples
Eddy currents cause energy to be lost. More accurately, eddy currents transform more useful forms of energy, such as kinetic energy, into heat, which is generally much less useful. In many applications the loss of useful energy is not particularly desirable, but there are some practical applications. One is in the brakes of some trains. During braking, the metal wheels are exposed to a magnetic field from a coil, generating eddy currents in the wheels. The magnetic interaction between the applied field and the eddy currents acts to slow the wheels down. The faster the wheels are spinning, the stronger the effect, meaning that as the train slows the braking force is reduced, producing a smooth stopping motion. The AC Magnetic module can readily be used to simulate eddy current breaking mechanism.
A heavy-duty vehicle Eddy current retarder
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Induction heating is the process of heating a metal object by electromagnetic induction, where eddy currents are generated within the metal and resistance leads to Joule heating of the metal. An induction heater, for any process, consists of a coil, through which an AC current is passed. Induction heating allows the precision heating of an applicable item, for applications from surface hardening to melting. Often, iron and its alloys respond best to induction heating, due to their ferromagnetic nature. The precision and the heating profile very much depend on the coil shape and position as well as the delivered power. The name of the game is to achieve a precise and thorough heating while minimizing the power used. The AC Magnetic module can be the ideal workbench to study various shapes and configurations.
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Analysts most often look for the highest reactions because the analysis under the maximum loads shows the maximum stresses experienced.
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Induction heating coils
Electromagnetic clutches and brakes
Induction heating machine
Michael Faraday built the first transformer in 1831. Ever since,
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Analysts most often look for the highest reactions because the analysis under the maximum loads shows the maximum stresses experienced.
people have been fascinated by this rather simple device. Many subjects have been thoroughly studied such as Eddy current losses, winding resistance, hysteresis losses, mechanical losses, stray losses, and cooling system. Never the less, people are still trying to perfect transformers. In recent years there have been growing concerns about exposure of people as well as electronic equipment to emission from high power transformers. This trend has resulted in an increasing demand on transformer shields that are light, electromagnetic emission proof, and at the same time cool. Meeting such concurrent criteria is by no means an easy task. The AC Magnetic module would definitely facilitate this endeavour.
A shielded transformer
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The three-phase induction AC motor is probably the most rugged of all electric motors due to their affordability, robustness, and high efficiency. To get a perspective on how important the three-phase motor is, all you need to know is that this motor is used in nine out of ten industrial applications. Recent designs of induction motors often include rotors with skewed slots and involute stator windings to minimize torque ripples. Thanks to the SolidWorks powerful geometrical capabilities, in COSMOSEMS modeling AC induction motors is easy and accurate.
A fan induction motor
Inside an induction motor
Why Transient Magnetic Analysis?
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Take into account both eddy current and saturation in devices that use time varying magnetic fields such as loudspeakers and induction machines. Optimize the Non-Destructive Testing (NDT) and Non-Destructive Evaluation (NDE) sensors to detect deep flaws and cracks. Study time varying devices such as magnetic heads, pulsed power transformers, and electromagnetic launchers. Study the response of pulsed power electronic equipment after a power failure or switch off.
Keywords Transient magnetic, saturation, B-H curve, Eddy current, skin effect, NDT, NDE, magnetic field, magnetic flux, flux density, inductance, coil, motor, solenoid, force, torque, magnetic circuit, flux linkage, Eddy current losses, loudspeaker, magnetic head, and pulsed equipment. Examples
Magnetoresistive random access memory (MRAM) is a new memory technology that makes use of the magnetic spin properties of electrons instead of their electrical charge. MRAM is considered by many magnetic memory experts to be an excellent candidate for a universal memory because it combines the speed of static random access memory (SRAM), the non-volatility of flash memory, as well as the good reliability characteristics. However, it can easily be disrupted by external magnetic fields generated by a nearby disk drive or power supply. Therefore, it is imperative to magnetically shield the die from such fields. The shield effectiveness depends on the magnetic permeability and geometry. In particular, the material should not reach saturation; otherwise it would act just like air. In addition, because of the limited space the shield must be as thin as possible. Meeting such stringent requirements is often challenging. Furthermore, the impinging fields are often times transient in nature. Therefore, the Transient Magnetic module is a valuable tool to a MRAM designer.
IBM MRAM Chips
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Eddy Current Testing (ECT) is a powerful NDT/NDE technique to detect defects, flaws, and discontinuities without impairing the
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Analysts most often look for the highest reactions because the analysis under the maximum loads shows the maximum stresses experienced.
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Analysts most often look for the highest reactions because the analysis under the maximum loads shows the maximum stresses experienced.
intended use of the material. However, it has several restrictions including the limit in depth to around 6 mm and the saturation of the ferromagnetic materials. Recently, a modified technique has been introduced called Pulsed Eddy Current (PEC) technique. Unlike ECT that uses single frequency time harmonic eddy current, PEC uses pulsed eddy current that has a broad band response with multiple frequencies. This difference actually allows the PEC to be used for multiple and deeper thicknesses as well as for ferromagnetic materials. The Transient Magnetic module is the perfect workbench for studying PEC systems.
A Pulsed Eddy Current system
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Magnetic actuators are widely used today in various systems such as antilock brakes, magnetic heads, and industrial automation. It is generally desired that such actuators respond quickly when turned- on. To simulate the process of turning on and off an actuator, the transient magnetic phenomenal must be studied. The Transient Magnetic module is the suitable tool to study such phenomenal and design fast turned-on actuators.
Actuators
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