Identifying a position of a brushless dc motor
AssigneeMarvell World Trade Ltd.
InventorsYichao WANG, Foo Leng LEONG
Life of this patent
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Abstract
A method for identifying a position of a multi-phase brushless motor includes applying a plurality of detection voltage pulses to the motor, each detection voltage pulse corresponding to a respective driving phase of the motor, measuring a time period associated with a current reaching a predetermined current limit for each applied detection voltage pulse, and identifying a driving phase associated with a shortest time period for the current to reach the predetermined current limit.
Claims20
A method for identifying a position of a multi-phase brushless motor, the method comprising:
- applying a plurality of detection voltage pulses to the motor, each detection voltage pulse corresponding to a respective driving phase of the motor;
- measuring a time period associated with a current reaching a predetermined current limit for each applied detection voltage pulse;
- and
- identifying a driving phase associated with a shortest time period for the current to reach the predetermined current limit.
An apparatus, comprising:
- a voltage pulse circuit configured to generate a plurality of detection voltage pulses;
- and
- a position identification circuit configured to determine a single detection voltage pulse of the plurality detection voltage pulses according to a plurality of currents associated with respective detection voltage pulses of the plurality of detection voltage pulses.
A method for identifying a position of a three-phase brushless DC motor, the method comprising:
- raising a voltage level of a first detection voltage pulse to be applied to the three-phase brushless DC motor for each phase of the three-phase DC brushless motor;
- applying the first detection voltage pulse to the three-phase brushless DC motor having the raised voltage level;
- applying detection voltage pulses to the three-phase brushless DC motor having voltage levels similar to the voltage level of the first detection voltage pulse;
- measuring a time period associated with a phase current reaching a predetermined current limit for each applied detection voltage pulse;
- and
- identifying a phase associated with a shortest time period for the phase current to reach the predetermined current limit.
Dependencies are inferred from the claim text.