Patent ID: 6522093
Filing Date: 2003-02-18
Classification: H02P

Abstract:
A method for driving a brushless DC motor, in said method, an induced magnetic field of windings current on a stator exerts a force tangent to a rotor on a plurality of magnetic arcs of said rotor to drive said rotor to rotate in a predetermined direction, wherein said induced magnetic field of said windings current on said stator will exert a reverse force on said plurality of magnetic arcs of said rotor tangent to said rotor on said plurality of magnetic arcs of said rotor, then a direction of said induced magnetic field of said windings current on said stator interchanges, and then drive said rotor to keep in rotating in said predetermined direction when said rotor reaches a critical angular position, said method comprises the steps of:sensing a magnetic field of said rotor; generating a driving control signal, wherein said windings current is inactive by said driving control signal when said rotor rotates to be within a specific angular distance from said critical angular position; controlling said induced magnetic field of said windings current on said stator to be generated and commuted based on said driving control signal wherein said induced magnetic field of said windings current on said stator is controlled to be zero when said windings current is inactive by said driving control signal; and driving said rotor to rotate according to said force tangent to said rotor exerted by said induced magnetic field of said windings current on said stator.