# US 10,312,847 B2 · Motor control using phase current and phase voltage > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,847 B2 - Document ID: US10312847B2 - Status: Granted - Kind: B2 - Application number: 15/149,448 - Filed: 2016-05-09 - Published: 2017-11-09 - Granted: 2019-06-04 - Earliest claimed: 2016-05-09 - Assignees: Allegro MicroSystems, LLC - Applicants: Allegro Microsystems, LLC - Inventors: Yisong Lu - Web page: https://patentgrep.com/patent/US10312847B2 ## CPC - H02P 27/08: with pulse width modulation - H02P 6/18: without separate position detecting elements - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract Methods and apparatus to control a three-phase BLDC motor using phase current and phase voltage at zero current detection and a driving current derived from a bus current, for example. The driving current can be combined with a difference angle with an output provided to a controller to control a speed of the motor. ## Claims ### Claim 1 A method of controlling a three-phase BLDC motor, comprising: receiving phase current signals for the BLDC motor; determining a first angular difference between a phase current and a phase voltage of the BLDC motor, the difference between the phase current and the phase voltage of the BLDC motor being determined based on a voltage driving angle corresponding to zero current detection for the phase current signals, the voltage driving angle corresponding to a range of zero to three-hundred sixty degrees; determining a second angular difference between an advance angle and the first angular difference; determining a driving current derived from a bus current of the BLDC motor; combining the second angular difference and the driving current to generate an output; and feeding the output to a control loop for controlling speed of the BLDC motor. ### Claim 2 (depends on 1) The method according to claim 1, further including generating the voltage driving angle by using a proportional-integral-derivative (PID) controller that is part of the control loop. ### Claim 3 (depends on 1) The method according to claim 1, wherein the voltage driving angle corresponds to a position relative to a rotor magnet having a north N pole and a south S pole. ### Claim 4 (depends on 1) The method according to claim 1, wherein the voltage driving angle corresponds to an input of a sinusoidal function of the phase voltage. ### Claim 5 (depends on 1) The method according to claim 1, wherein the advance angle is provided as an input signal. ### Claim 6 (depends on 1) The method according to claim 1, further including determining the driving current from an average bus current. ### Claim 7 (depends on 1) The method according to claim 1, wherein the driving current is proportional to a bus current divided by an amplitude command. ### Claim 8 (depends on 1) The method according to claim 1, further including employing a proportional-integral-derivative (PID) controller as part of the control loop and using an output of the PID controller as a lookup to adjust motor speed. ### Claim 9 (depends on 8) The method according to claim 8, further including combining the lookup, an amplitude command, and a voltage to control motor speed. ### Claim 10 A system to control a three-phase BLDC motor, comprising: a first module to receive phase current signals for the BLDC motor and output three-phase current direction information; a second module to determine a first angular difference between a phase current and a phase voltage of the BLDC motor, the difference between the phase current and the phase voltage of the BLDC motor being determined based on a voltage driving angle corresponding to zero current detection for the three-phase current direction information, the voltage driving angle corresponding to a range of zero to three-hundred sixty degrees; a third module to determine a second angular difference between an advance angle and the first angular difference; a fourth module to determine a driving current derived from a bus current of the BLDC motor; a combiner to combine the second angular difference and the driving current to generate an output; and a control loop module having a computer processor to receive the output of the combiner for controlling speed of the BLDC motor. ### Claim 11 (depends on 10) The system according to claim 10, wherein the system comprises an IC package having first, second, and third outputs for proving outputs to each of the three phases. ### Claim 12 (depends on 10) The system according to claim 10, wherein the control loop module comprises a proportional-integral-derivative (PID) controller that is configured to generate the voltage angle. ### Claim 13 (depends on 10) The system according to claim 10, wherein the voltage driving angle corresponds to a position relative to a rotor magnet having a north N pole and a south S pole. ### Claim 14 (depends on 10) The system according to claim 10, wherein the advance angle is provided as an input signal. ### Claim 15 (depends on 10) The system according to claim 10, further including a bus current module configured to determine the driving current from an average bus current. ### Claim 16 (depends on 15) The system according to claim 15, wherein the driving current is proportional to a bus current divided by an amplitude command. ### Claim 17 (depends on 10) The system according to claim 10, further including first, second, and third pairs of switching elements for generating the outputs to each of the three phases of the motor. ### Claim 18 (depends on 17) The system according to claim 17, further including a gate driver module to receive pulse-width modulated (PWM) signals and generate the outputs to each of the three phases of the BLDC motor. ### Claim 19 (depends on 10) The system according to claim 10, wherein the system comprises an IC package having first, second, and third pins for providing outputs to each of the three phases and a fourth pin to receive a speed demand signal.