Abstract
Energy saving control is desirable for magnetically levitated (MAGLEV) vehicles. Hybrid magnets controlled with zero power control system was able to reduce the exciting power. But such a conventional system needed to feed bipolar current and then the excitation system was complicated. To achieve a simple excitation system, a hybrid magnet with permanent magnets and divided cores was made. The magnet was a salient-pole type magnet and the poles were placed in two rows. Each pole of the iron cores was equipped with a coil to control both levitation force and lateral damping force. The coils of one side of the divided core were excited with a direct current driver so as to produce the same polarity as the permanent magnet and the others were excited the opposite polarity. The two sets of the coils were excited with direct current drivers each of which had one IGBT. The system needed only two IGBTs per magnet while the conventional zero power systems needed four IGBTs per magnet. According to our test results, the energy consumption was very small and the levitation part was able to start levitating from both upper and lower touch-down positions. In this paper, the characteristics of the proposed excitation system are shown.
