Contactless Inductive Power Supply

Inductive Power Supply is a new technology which is advantageous in comparison to current-rails, cables and battery supply systems. The advantages of this new developed technology are based on maintenance-free operation, no sparkling effects due to contact problems, complete isolation of primary and secondary conductors and ruggedness against dust and environmental conditions. The basis for this new developed technology is the use of a secondary coil, located on the moving transportation system inductively coupled to a primary winding which is located and fixed along the track of the transportation system. There are a number of technical problems to be solved to make this contactless inductive power supply working with high efficiency and to become an economically power supply system. The use of high frequency leads to acceptable dimensions of the active secondary coil. The distributed winding on the primary leads to a large impedance and therefore corresponding apparent power is required. The effect of specific compensating technologies is that only real power has to be supplied by the high frequency power supply on the primary. In addition special attention has to be given to the design of the secondary coil arrangement to provide the magnetization of the air gap between primary winding and secondary coil. The different design aspects of contactless inductive power supply will be presented.