PURPOSE: To make it unnecessary to realize synchronization of a switch element gate signal in a magnetic bearing drive circuit and improve reliability by reducing the number of elements.
CONSTITUTION: An electric magnet at a bearing part is wound by the first electro-magnetic coil 11 and the second electro-magnetic coil 12. One end of the electro-magnetic coil 11 is connected to the negative DC power supply while the other end is connected to the positive DC power supply through a switch element 1. One end of the electro-magnetic coil 12 is connected to the negative DC power supply while the other end is connected to the positive DC power supply through a diode 3. The electro-magnetic coils 11, 12 are wound so that the direction of the magnetic flux which is generated when the current passes from the switch element 1 to the negative DC power supply through the electro- magnetic coil 11 may be same as the direction of the magnetic flux when the current passes from the negative DC power supply to the positive DC power source through the electro-magnetic coil 12 and the diode 3.
KUME TSUNEO
SONODA SUMITOSHI
TAJIMA EIJIROU
