As common as they are, electromagnetic devices are not as widely understood. An electromagnet uses an electrical current to generate a magnetic field. The strength of that field is directly proportional to the level of current supplied to the magnet, and the field’s polarity can be flipped by changing the direction of the electrical current. Electromagnets serve a variety of purposes in many day-to-day technologies, particularly in electromechanical and electronic devices.
We’ll cover some of the most common uses of electromagnets in the world today, both in consumer products and for industrial applications, making many modern technologies possible.
Real World Electromagnet Applications in Electronics
Most people don’t directly see electromagnets in their daily life, but they are no less often used. Electromagnets are found in countless consumer and commercial products, including:
- TVs
- Audio Equipment
- Computers
- Cars
- Elevators
- Copy Machines
- MRI/CT Scan Machines
Real World Electromagnet Applications in Power Generation
Generating power involves converting sources of primary energy into electric power. An electric generator stores mechanical energy in the form of electrical energy by using a wire coil in a magnetic field. This is done by rotating the coil, which induces a current, and industrial-scaled applications accomplish this with a large, rapidly spinning turbine to produce massive amounts of electrical current.
This electrical energy can be stored and converted back into mechanical energy for a variety of purposes – such as running a motor. To do so, an electromagnet is supplied with a reverse current, creating a magnetic field that causes the magnet’s coil to spin, along with anything connected to it.
Electromagnets make it possible to convert mechanical energy into electricity, and then back into mechanical energy. The electromagnetic device that converts these energies is called an actuator, which consists of a stationary and a moving component (such as a rotor), where the magnetic fields produce torque and force that can be harnessed. This same principle makes it possible to use an electromagnet’s induction coil to measure the magnetic field itself, making electromagnets capable of functioning as sensors.
To summarize, electromagnets are used in four different ways in the power generation process:
- Generators
- Motors
- Actuators
- Sensors
Real World Electromagnet Applications in Medicine
Medical devices such as Magnetic Resonance Imaging machines (MRIs), use magnets thousands of times more powerful than your average kitchen magnet to generate signals in the radio-frequency range, which the device then measures and translates into images. This results in highly detailed pictures of bones, organs, and various tissues.
Magnets are also applied in some cancer treatments, where a doctor injects magnetically sensitive fluid into the area around the tumor and uses a powerful magnet to generate heat in the body. The goal is to kill the cancer cells without harming the healthy tissues.
These are just two common medical uses of magnets – others include:
- Scanners
- X-ray equipment
- Dialysis machines
- Disinfectant dispensers
- Electromagnetic therapies
Real World Electromagnet Applications in Aerospace
Aerospace engineers have developed an almost entirely separate field of magnetics. Specialized uses involve sending finely controlled current and voltage to receiving systems to maintain altitude and other flight dynamics. In reverse, this also enables them to track the location and flight path of various aircraft and devices.
Much of aerospace engineering would not be possible without electromagnetic technology. Electromagnets power many standard and specialized aerospace devices, such as:
- Flight control covers for both commercial and combat aircraft
- Missile programs
- Aircraft loudspeakers
- Traveling-wave tube (TWT) radar
- Permanent Magnet (PM) generator rotor assemblies
- Fuel pumps
- Flow regulators
- Cryogenic magnets suited for space environments
- Magnetic holders for aircraft seats
- Position-calibration and speed sensors
- Air-compressor components
- Motorized generators
- Tachometer generators
Electromagnets from Custom Coils
Not many technologies are as ubiquitous to modern life while remaining largely hidden from direct experience as electromagnets. Just as electromagnetic devices have driven much of modern technology forward without being often credited as such, Custom Coils, Inc. has been quietly and dutifully driving the electromagnetic industry forward since 1978.
With a highly customer-centric business model, our expert engineers work closely with every client to design and manufacture precision-engineered electromagnets for a wide variety of end uses. For any questions or to let us know about your electromagnetic needs, don’t hesitate to request a quote or contact us.
Custom Coils Inc. designs and manufactures custom specialty coils for a variety of industries and applications. For even the most challenging projects, our experts can deliver high-quality design conceptualization, prototype development, testing, and production. This page will explain how electromagnetic coils work, their different types and applications, and important design considerations when creating custom solutions.
What are Electromagnetic Coils?
An electromagnetic coil, also known as an electric coil or inductor, is an electrical conductor containing a set of conductive wires wrapped around a specified shape and size. This can be a self-supporting (air core) design or include a specified core (ie. iron, ferrite) . Electrical coils are simple electronic components that provide inductance in an electromagnetic circuit.
There are many coil types to meet the needs of various equipment. Electromagnetic coils can vary by wire gauge, length, coil diameter, core material, and other factors. Since electromagnetic coils are powered by electricity, they can be turned on and off easily. Their magnetic strength can be altered by increasing or decreasing the electricity that flows around their core.
How Do Electromagnetic Coils Work?
Electromagnetic coils consist of conductive wire wrapped in a specific size and shape, producing a magnetic field. The magnetic field grows stronger when there are more turns of wire on the coil. Electromagnetic field strength is determined by the number of amp turns, the material selection of the core, and the strength of current. Removing electrical input disables the magnet.
When added to a wire coil, certain core materials can increase the strength of the magnetic field. Ferromagnetic materials—cobalt, nickel, iron, and steel—can amplify a denser magnetic field for the coil.
Types of Electromagnetic Coils
Since electromagnetic coils are critical components used in many industrial applications, the coils must meet the varied demands of each one. The following are some of the most common types of electromagnetic coils and how they’re used.
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- Automotive electric coils: Ignition coils in automobiles typically consist of two sets of copper wires wrapped around an iron core. The primary winding is a heavy wire, while the secondary wire is smaller and lighter.
- Energy electric coils: These coils must be engineered to withstand harsh environmental conditions in remote locations.
- Electronic electric coils: Made from finely wound wire, coils for electronic devices are in high demand. Circuit board coils go into laminated transformers.
- Electric guitar electric coils: The single coil design is the most popular form of electric guitar coil, but another form is the double coil, which helps cancel out interference.
- Medical electric coils: Coils in medical equipment, such as Radiation Therapy Systems, must be reliable. These typically high power applications require very precise process and testing procedures.
- Military electric coils: Like medical coils, military coils must be accurate and reliable. They must also be able to perform in harsh conditions. These coils are commonly used in guidance systems, sensors, and navigation systems.
- Transportation electric coils: Railroad tracks, armatures, and signaling devices all use these coils, which can withstand the constant vibrations that occur in these environments.
- Wind-powered generator electric coils: These coils must withstand temperatures up to 200 °C. They are made from lightweight materials and insulated for added protection.
- Flowmeter electric coils: Used to measure the volume of liquid or gas going through a pipe, flowmeter coils must match the radius of the pipe.
- Traffic light sensor electric coils: Inductance meters attach to these coils and change when a car enters its field, alerting the traffic light of the car’s presence.
- Transformer electric coils: Transformers utilize multiple coils to conduct electricity, with primary windings on one side and secondary windings on the opposing side.
- Linear Accelerators coils: Electromagnets (Dipole magnets) are used extensively for beam guiding and bending to move charged particles where they need to go.
Electromagnetic Coil Applications
Electromagnetic coils vary in size, shape, and material depending on their application. While there are many industries that use electromagnetic coils, three industries in particular rely on coils for critical applications.
Medical
Electromagnetic components are vital to many types of medical equipment, including heart rate monitors, Radiation therapy systems, MRI systems and more. Diagnostic equipment—such as electrocardiogram (EKG) and electroencephalogram (ECG) machines—also require electromagnetic coils.
Military
The military depends on electromagnetic coils for missile defense, protecting allied signals, and jamming enemy signals. Electromagnetic coils also apply to high-velocity electromagnetic rail guns.
Aerospace
Aerospace applications for transformers, inductors, and other electromagnetic parts must be highly precise and adhere to stringent guidelines. Electromagnetic aircraft launch systems, for example, must successfully launch aircraft from carriers.