AC/DC Module

Electrical engineering is one of the technological cornerstones of modern society. Electricity is used to distribute power and information with a minimum of losses and delay. Imagine what life would be without it. This minicourse contains four examples that illustrate the modeling of electromagnetic devices in the AC/DC Module for COMSOL Multiphysics.

• The first model deals with induced currents in conducting materials near an AC conductor. A metallic plate is placed near a 50-Hz AC conductor. We investigate how the resulting eddy-current distribution and dissipated power in the plate depend on the plate’s conductivity and permeability.
• The second example models a parallel-plate capacitor used in MEMS applications. It demonstrates how to perform an electrostatic analysis and how to extract the lumped capacitance of a device.
• The third model shows how the circular motion of a rotor with permanent magnets generates an induced EMF in a stator winding. The generated voltage is calculated as a function of time during the rotation. The model also shows the influence on the voltage from material parameters, rotation velocity, and number of turns in the winding.
• The final example models a submarine’s magnetic signature, that is, the local disturbance in the earth's magnetic field that the sub causes. An important step in the design of naval ships is to minimize their magnetic signature in order to avoid detection by the enemy. This model demonstrates a powerful technique that circumvents the difficulties associated with volumetric meshing of thin sheets, and it allows for accurate computations of the magnetic signatures of ships, cars, and other vehicles.