4 results about "Counter-electromotive force" patented technology

The invention discloses an automobile electronic oil pump driving system and relates to the field of automobile driving. The automobile electronic oil pump driving system comprises an oil pump, a brushless motor, a controller and a controller upper cover, the brushless motor comprises a motor core, a motor shell and a motor rear end cover, and the oil pump is installed at the output end of the brushless motor. The controller comprises a power supply, a power supply control module, an MCU module, a communication module, a pre-driving and driving module, an angle position sensor and a motor driving chip with a position estimation function; the controller switches an inductive mode in real time in a low-temperature cold start environment to acquire angle position data through the angle position sensor, and controls the rotating speed of the motor by adopting an inductive sine wave algorithm; a non-inductive mode is switched in real time in a position sensor failure environment, counter electromotive force of the brushless motor is collected through a motor driving chip with a position estimation function, and through cooperation with a position estimation algorithm of control software, the angle position of the motor is estimated, and control over the rotating speed of the motor is achieved.

A double high axial motor capable of effectively reducing back electromotive force torque pulsation comprises a sectional armature (1), a rotor disc (2), a bearing pressure plate (3), an iron core (4) and a stator bar (5), and is characterized in that the iron core (4) of the sectional armature (1) adopts an axial motor separation design, a bearing is fixed on a stator by the bearing pressure plate (3), the iron core (4) is fixed by the sectional armature (1) through the stator bar (5), and an external motor case is connected; the iron core (4) is made of a soft magnetic composite material, arc-shaped surfaces are designed in sequence according to different pole numbers, the part close to a wire inlet end is small in radian or is not arranged, and the part far away from the wire inlet end is appropriate in radian, so that the salient pole rate is improved, the influence of inter-pole resistance on counter electromotive force is reduced, and the permanent magnets can be effectively utilized; materials are saved, and power and torque are improved.

The embodiment of the invention discloses an electric vehicle control method and an electric vehicle controller. The method comprises the steps of 1, when a starting signal of a user is received, outputting a first starting driving signal comprising a forward driving signal and a reverse driving signal according to the starting signal, wherein the duty ratio of the first starting driving signal isthe same as that of the starting signal, and the direction of current applied to the motor by the reverse driving signal is opposite to that of current applied to the motor by the forward driving signal; sampling a first counter electromotive force of a motor suspension phase when the forward driving signal is applied to the motor, and sampling a second counter electromotive force of the motor suspension phase when the reverse driving signal is applied; and outputting a second starting driving signal according to the difference between the first counter electromotive force and the second counter electromotive force. The accurate commutation time is obtained according to the variation trend of the difference between the two counter electromotive forces, and a starting signal is applied tostably start the motor. The problem that the motor control is out of step when a driving signal is generated by using a zero-crossing detection method in the prior art is solved.