| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve such a problem that the acceleration of a rotor causes an increase in magnitude of a back electromotive force and it gradually becomes difficult to supply driving current (i.e., power) into the electric machine. <P>SOLUTION: A method of controlling an electric machine includes a step of sequentially exciting and freewheeling a winding of the electric machine, the winding being excited in advance of zero-crossing of a back electromotive force in the winding by an advance angle and being freewheeled over a freewheel angle; and a step of varying the advance angle and the freewheel angle in response to changes in the speed of the electric machine. Additionally, a control system for an electric machine, and a product incorporating the control system and electric machine are provided. <P>COPYRIGHT: (C)2011,JPO&INPIT |
