The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 08, 2004
Filed:
Sep. 25, 2002
Japan Servo Co., Ltd., Tokyo, JP;
Abstract
The controller comprises current sensors for detecting motor currents, an inverter containing a current control means for feeding currents to motor windings, a coordinate transformer that transforms the motor currents in a fixed coordinates system into currents in a first rotational coordinates system, and an angle calculator that transforms a command pulse into a command angle. A second rotational coordinates system composed of a dp axis and a qp axis perpendicular to the dp axis is determined from the command angle. A command current on the dp axis is set to be a value corresponding to a motor current amplitude and another command current on the qp axis is set to be zero. The motor current is projected on the dp and qp axes and controlled so as to make the components on the dp and qp axes coincide with the respective command currents on the dp and qp axes.