Abstract: A method for controlling stray electromagnetic fields for a vehicle with an inductive charging system and a method for providing feedback to a vehicle operator for an inductive charging system is characterized by the addition of alignment coils to a vehicle mounted secondary coil. The methods provide sensors to detect the relative positions of the primary coil and secondary coil by determining voltages induced in the alignment coils by a magnetic field generated by the primary coil. The methods include providing feedback to the vehicle operator to guide the alignment of the secondary coil relative to the primary coil and directing the vehicle operator to position the secondary coil within an alignment zone so as to control stray electromagnetic fields.

Abstract: A method and apparatus for aligning a vehicle with an inductive charging system is characterized by the addition of alignment coils to a secondary coil on the vehicle. For efficient inductive charging, it is necessary that the vehicle mounted secondary coil be aligned with a stationary primary coil of a transformer of the inductive charging system. When the primary coil is energized, it produces a magnetic field which induces a voltage in the alignment coils as a function of the proximity of the alignment coils to the central axis of the primary coil. The voltage differential between opposed pairs of alignment coils is determined by a comparator which then generates a directional signal which can be used by the operator of the vehicle to position the vehicle for closer alignment of the vehicle secondary coil with the primary coil and more efficient charging.

Abstract: A method for aligning a vehicle with an inductive charging system is characterized by the addition of alignment coils to a secondary coil on the vehicle. For efficient inductive charging, it is necessary that the vehicle mounted secondary coil be aligned with a stationary primary coil of a transformer of the inductive charging system. When the primary coil is energized, it produces a magnetic field which induces a voltage in the alignment coils as a function of the proximity of the alignment coils to the central axis of the primary coil. The voltage differential between opposed pairs of alignment coils is determined by a comparator which then generates a directional signal which can be used by the operator of the vehicle to position the vehicle for closer alignment of the vehicle secondary coil with the primary coil and more efficient charging.

Abstract: A method and apparatus for hands free inductive charging of batteries for an electric vehicle is characterized by the use of a transformer having a primary coil connected with a charging station and a secondary coil connected with a vehicle. More particularly, the when the vehicle is parked adjacent to the charging station, the primary coil is displaced via a self alignment mechanism to position the primary coil adjacent to the secondary coil to maximize the inductive transfer of charging current to the secondary coil. The self alignment mechanism preferably utilizes feedback signals from the secondary coil to automatically displace the primary coil in three directions to position the primary coil for maximum efficiency of the transformer.

Abstract: A method and apparatus for hands free inductive charging of batteries for an electric vehicle is characterized by the use of a transformer having a primary coil connected with a charging station and a secondary coil connected with a vehicle. More particularly, the when the vehicle is parked adjacent to the charging station, the primary coil is displaced via a self alignment mechanism to position the primary coil adjacent to the secondary coil to maximize the inductive transfer of charging current to the secondary coil. The self alignment mechanism preferably utilizes feedback signals from the secondary coil to automatically displace the primary coil in three directions to position the primary coil for maximum efficiency of the transformer.