New and fast procedures for calculating the mutual inductance of coaxial circular coils (disk coil-circular coil)

Summary form only given. This paper deals with two new efficient approaches for determining the mutual inductance between disk coils and circular coils. Circular coils are widely used in various electromagnetic applications such as coil guns and tubular linear motors. The mutual inductance as a fundamental electrical engineering parameter for a coil can be computed by applying the Biot-Savart law directly or using other alternate methods. In the first approach using the Biot-Savart law we obtain the mutual inductance of presented coils, in the form of complete elliptical integrals of the first kind and Hamain's Lambda function. We also propose another approach - the filament method for thin coils that uses Maxwell's coils which replace the thin disk. This method is very simple for practical applications. However, it takes more computational time if more accurate results are needed.