Brushless dynamo for motor vehicle - has combined excitation field produced by excitation winding and permanent magnet

摘要

The brushless dynamo has its magnetic excitation circuit in combination with the corresponding excitation winding provided with a permanent magnet in order to produce a hybrid excitation system. The magnetic flux generated by the excitation winding (20) cooperates with the magnetic flux (F3) from the permanent magnet forming part of a ring of magnetic material so that the permanent magnet is connected to the magnetic circuit of the rotor. The excitation winding is held by a hollow drum (28) open at one end and partly enclosing the rotor so that an air gap is formed between the two. The advantage lies in the constant magnetic properties of the excitation circuit and little maintenance.