Abstract: A permanent magnet excited electric machine includes a stator and a moving part movable relative to the stator. One of the stator and moving part has an electric winding system in the form of a single or multiple 3-phase system. The other one of the stator and moving part has permanent magnets. The winding system, in the form of a delta connection, has an inductance such that the related total reactance xB during rated operation according to xB=?B·LY·PB/(Z3P·Ui,B2) is at least 0.8, wherein ?B is the electric angular frequency of the winding system during rated operation, LY is the phase inductance of the winding system in star connection, PB is the power of the machine during rated operation, Z3P is the number of 3-phase systems of the machine, and Ui,B is the amount of the induced conductor voltage during rated operation.

Abstract: An interface circuit, which uses electromagnetic induction to perform a signal transmission, comprises a transmission coil and a transmission circuit that provides a signal to the transmission coil, thereby causing the transmission coil to output a triangular or roughly triangular magnetic field signal.