Automotive PM Surface Alternator, Analyse with Experiments

The electrical energy in a car, when the combustion engine is running, is made, for the most period of time (peak loads can, also, be taken by the battery), by the claw-poles alternator. The article presents an alternator with permanent magnet surfaces in the rotor, the stator being identical, from a constructive point of view, with the stators from the classic alternators (Lundell). The permanent magnets are rectangular in shape and replace the claw-type poles from the the classic alternators with the coiled rotor. To obtain a variable speed, the alternator with permanent magnets is driven by a belt through a three-phase induction motor powered by a variable frequency driver. Experiments were performed with this alternator at variable speed, without and with buck converter (two types) for voltage stabilization, without and with power resistors (of different values) and with lead-acid battery. The use of alternators with permanent magnets in vehicles is another solution for producing electricity and can be a more reliable solution than the classic one.