# US 10,873,280 B2 · Methods and apparatus for motor startup with sinusoidal phase current > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,873,280 B2 - Document ID: US10873280B2 - Status: Granted - Kind: B2 - Application number: 15/374,154 - Filed: 2016-12-09 - Published: 2018-06-14 - Granted: 2020-12-22 - Earliest claimed: 2016-12-09 - Assignees: Allegro MicroSystems, LLC - Applicants: Allegro MicroSystems, LLC - Inventors: Yisong Lu; Lyndon Ambruson - Web page: https://patentgrep.com/patent/US10873280B2 ## CPC - H02P 6/16: Circuit arrangements for detecting position - H02P 6/22: in a selected direction of rotation - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract Methods and apparatus for controlling a three-phase motor and providing sinusoidal phase currents during startup. In embodiments, differential outputs from a magnetic field sensing element are used to generate a polarity signal used to provide a motor direction drive signal. An amplitude signal derived from the magnetic field sensing element and a measured motor current are used to generate a current amplitude signal. A PWM module generates signals for driving the motor with sinusoidal phase currents from the current amplitude signal and the motor direction drive signal. ## Claims ### Claim 1 A method for three-phase motor startup, comprising: receiving differential outputs from a magnetic field sensing element; generating a polarity signal from the differential outputs; receiving the differential outputs and generating an amplitude signal; generating a motor direction drive signal from the polarity signal; and generating sinusoidal motor drive signals during the motor startup from a measured motor current signal and the amplitude signal, wherein the motor drive signals drive the motor in a direction corresponding to the motor direction drive signal. ### Claim 2 (depends on 1) The method according to claim 1, wherein the magnetic field sensing element comprises a Hall element. ### Claim 3 (depends on 1) The method according to claim 1, wherein the sinusoidal motor drive signals during motor startup are generated from a single Hall element, which comprises the magnetic field sensing element. ### Claim 4 (depends on 3) The method according to claim 3, wherein the motor direction drive signal corresponds to a position of the signal Hall element in relation to phases of the motor. ### Claim 5 (depends on 1) The method according to claim 1, wherein the magnetic field sensing element comprises an anisotropic magnetoresistance (AMR) element. ### Claim 6 (depends on 1) The method according to claim 1, wherein the magnetic field sensing element comprises a giant magnetoresistance (GMR) element. ### Claim 7 (depends on 1) The method according to claim 1, wherein the magnetic field sensing element comprises a tunneling magnetoresistance (TMR) element. ### Claim 8 (depends on 1) The method according to claim 1, further including using a comparator to generate the polarity signal. ### Claim 9 (depends on 1) The method according to claim 1, further including rectifying the differential outputs to generating the amplitude signal. ### Claim 10 (depends on 1) The method according to claim 1, further including using a proportional-integral (PI) controller to generate a control vector amplitude signal for a PWM signal generator from the amplitude signal and the measured motor current. ### Claim 11 (depends on 1) The method according to claim 1, wherein the motor comprises a brushless DC motor. ### Claim 12 A motor controller system comprising: a control module configured to receive polarity information generated from differential outputs that are output by a magnetic field sensing element positioned in relation to phases of a three-phase motor and amplitude information generated from the differential outputs that are output by the magnetic field sensing element, the control module configured to generate a motor driving direction signal corresponding to the received polarity information and to generate an amplitude control signal from the amplitude information and a measured motor current information; and a pulse width modulation (PWM) module configured to receive the amplitude control signal and the motor driving direction signal and generate control signals for switching elements driving the motor that provide sinusoidal phase currents to the motor during startup, wherein the motor drive signals drive the motor in a direction corresponding to the motor direction drive signal. ### Claim 13 (depends on 12) The system according to claim 12, wherein the magnetic field sensing element comprises a Hall element. ### Claim 14 (depends on 12) The system according to claim 12, wherein the sinusoidal motor drive signals during motor startup are generated from a single Hall element, which comprises the magnetic field sensing element. ### Claim 15 (depends on 14) The system according to claim 14, wherein the motor direction drive signal corresponds to a position of the signal Hall element in relation to phases of the motor. ### Claim 16 (depends on 12) The system according to claim 12, further including a comparator to generate the polarity signal. ### Claim 17 (depends on 12) The system according to claim 12, further including rectifying the differential outputs to generating the amplitude signal. ### Claim 18 (depends on 12) The system according to claim 12, further including a proportional-integral (PI) controller to generate a control vector amplitude signal for a PWM signal generator from the amplitude signal and the measured motor current. ### Claim 19 (depends on 12) The system according to claim 12, wherein the motor comprises a brushless DC motor. ### Claim 20 (depends on 12) The system according to claim 12, wherein the magnetic field sensing element comprises an anisotropic magnetoresistance (AMR) element. ### Claim 21 (depends on 12) The system according to claim 12, wherein the magnetic field sensing element comprises a giant magnetoresistance (GMR) element. ### Claim 22 (depends on 12) The system according to claim 12, wherein the magnetic field sensing element comprises a tunneling magnetoresistance (TMR) element. ### Claim 23 A motor controller system comprising: a control means for receiving polarity information generated from differential outputs that are output by a magnetic field sensing element positioned in relation to phases of a three-phase motor and amplitude information generated from the differential outputs that are output by the magnetic field sensing element, and to generate a motor driving direction signal corresponding to the received polarity information and to generate an amplitude control signal from the amplitude information and the motor current information; and a pulse width modulation (PWM) means for receiving the amplitude control signal and the motor driving direction signal and generate control signals for switching elements driving the motor that provide sinusoidal phase currents to the motor during startup, wherein the motor drive signals drive the motor in a direction corresponding to the motor direction drive signal. ### Claim 24 (depends on 23) The system according to claim 23, wherein the magnetic field sensing element comprises a Hall element. ### Claim 25 (depends on 23) The system according to claim 23, wherein the sinusoidal motor drive signals during motor startup are generated from a single Hall element, which comprises the magnetic field sensing element. ### Claim 26 (depends on 25) The system according to claim 25, wherein the motor direction drive signal corresponds to a position of the signal Hall element in relation to phases of the motor. ### Claim 27 (depends on 23) The system according to claim 23, further including a rectifier coupled to the differential outputs to generate the amplitude signal. ### Claim 28 (depends on 23) The system according to claim 23, further including a proportional-integral (PI) controller means for generating a control vector amplitude signal for a PWM signal generator from the amplitude signal and the measured motor current. ### Claim 29 (depends on 23) The system according to claim 23, wherein the motor comprises a brushless DC motor. ### Claim 30 (depends on 23) The system according to claim 23, wherein the magnetic field sensing element comprises an anisotropic magnetoresistance (AMR) element. ### Claim 31 (depends on 23) The system according to claim 23, wherein the magnetic field sensing element comprises a giant magnetoresistance (GMR) element. ### Claim 32 (depends on 23) The system according to claim 23, wherein the magnetic field sensing element comprises a tunneling magnetoresistance (TMR) element.