The role of magnets in wireless power transfer (WPT)

Published: 2023-04-22 10:53:35 • Daniel Gårdefelt

Wireless power transfer is a new type of technology that makes it possible to send electricity without having to connect it physically. Magnets are very important to the development of these systems because they make it possible to send power over long distances safely and efficiently.

Coupling of magnetic resonance
Most WPT systems are based on magnetic resonance coupling, which uses magnetic fields to send energy from one coil to another or between two or more coils. This process can be broken down into these steps:

Energy is created by passing an alternating current (AC) through a primary coil, which creates a magnetic field around the coil that changes over time.

Energy is transferred when the magnetic field of the primary coil interacts with a secondary coil at some distance, causing the secondary coil to produce an alternating voltage.

Energy is received when the voltage induced in the secondary coil is converted to direct current (DC) by a rectifier. This provides power to the device receiving energy.

Magnets in WPT systems: Advantages
Putting magnets in WPT systems has a number of advantages, such as:

Efficiency: Magnetic fields can move energy over long distances with little loss, so WPT systems are very efficient compared to other ways of moving energy wirelessly.

Safety: Because magnetic fields can pass through most things that are not magnetic, they do not harm people or electronics. This means that WPT systems can be used in a variety of locations.

Flexibility: WPT systems can be made to operate at a wide range of frequencies, power levels and distances, so they can be used in many different ways.

How WPT system is used
Magnets have made it easier to make WPT systems for many different uses, such as:

Consumer electronics: Wireless power transfer (WPT) systems are used to charge smartphones, tablets and other devices without charging cables. This makes the charging process easier.

Electric Vehicles (EV): Wireless charging stations can be placed in parking lots so that electric cars can be charged without having to be physically connected. This makes charging easier and reduces the need for charging infrastructure.

Medical Implants: Without the need for cords or batteries, WPT systems can be used to power medical implants such as pacemakers and cochlear implants. This reduces the risk of infection.

We can hereby state that magnets have been a very important part in the development of advanced technology such as wireless energy transmission because they make it possible to send energy over long distances in a safe and efficient way. As the need for wireless power solutions grows, magnets will continue to be an important part of how WPT systems will work in the future. WPT systems can be used in things like consumer electronics, electric cars and medical implants. This shows how this technology can change many aspects of our daily life.