Description
Quasi-static finite difference time domain (QS-FDTD) method is a modified version of the FDTD method for low-frequency problems.
Investigations about electromagnetic induction systems, magnetic sensors, metal detectors, magnetic resonance imaging, induction heating, induction motors, Eddy current nondestructive test systems, electromagnetic launchers (coil gun type), wireless power transfer, RFID applications, and controlled source electromagnetic system and so on, address increased number of low-frequency electromagnetic problems. Generally, a magneto-quasi-static (MQS) approximation is applied for the solutions of low-frequency problems in electromagnetics. This approximation leads to a diffusion process with neglecting displacement currents. However, keeping the displacement currents, Maxwell’s equations are valid at low frequencies. In this manner, the finite difference time domain (FDTD) method must be modified at low-frequency regime. In this modified version of the FDTD method, QS-FDTD, keeping the displacement currents, the propagation velocity is slowed down by a material scaling technique for dielectric permittivity. Therefore, the QS-FDTD method presents very accurate full wave solutions for low-frequency electromagnetic induction problems.
The following problems are examples of low-frequency electromagnetic problems, in which electromagnetic propagation problems can be solved exactly by QS-FDTD.
- Research based on electromagnetic induction systems,
- Magnetic sensors,
- Metal detectors,
- Magnetic resonance imaging,
- Induction heating,
- Induction motors,
- Eddy current non-destructive testing systems,
- Electromagnetic launchers,
- Wireless power transfer,
- RFID applications,
- Controlled welding electromagnetic systems
