EXCITATION CIRCUIT OF MAGNETIC BEARING AND TURBO- MOLECULAR PUMP UNIT

摘要

PROBLEM TO BE SOLVED: To provide an excitation circuit of a magnetic bearing and a turbo- molecular pump unit capable of miniaturizing in an entire apparatus and performing cost reduction and improving reliability by simplifying a circuit formation. SOLUTION: The excitation circuit of the magnetic bearing is to prepare trans-combination with electromagnet windings 1a and 1b and to connect a transistor 131 and gate driving circuit 131a to an power supply 133 in series at one side of the electromagnet windings and to connect a diode 135 regenerating electric power at other side of the electromagnet windings. A current detecting circuit is arranged in the electromagnet winding 1a. Further, the turbo-molecular pump unit is composed of a controlling unit having the excitation circuit of the magnetic bearing, and a turbo-molecular pump having the magnetic bearing.