# US 7,612,520 B2 · Method for operating a delta wound three-phase permanent magnet brushless motor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,612,520 B2 - Document ID: US7612520B2 - Status: Granted - Kind: B2 - Application number: 11/713,839 - Filed: 2007-03-05 - Published: 2008-09-11 - Granted: 2009-11-03 - Earliest claimed: 2007-03-05 - Assignees: Delphi Technologies, Inc. - Inventors: Curtis P. Cyran; Robert J. Disser - Web page: https://patentgrep.com/patent/US7612520B2 ## CPC - H02P 6/34: Modelling or simulation for control purposes - H02P 6/15: Controlling commutation time - H02P 7/281: the DC motor being operated in four quadrants - H02P 23/06: Controlling the motor in four quadrants - H02P 29/032: Preventing damage to the motor, e.g. setting individual current limits for different drive conditions - H02P 23/0086: {specially adapted for high speeds, e.g. above nominal speed} - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract Method for operating a delta wound three-phase permanent magnet brushless motor. A transition speed is determined in a quadrant of a speed versus torque curve above which speed continues to increase while current/torque decreases wherein actual phase current can be controlled in a current control modification manner which reduces requested phase current. The modification manner is determined for a quadrant, wherein a controller can use the modification manner to reduce the requested phase current to control the actual phase current when the speed is above the transition speed. The motor is controlled in a quadrant wherein, when the motor has a speed above the transition speed, the controller reduces the requested phase current in the modification manner and the controller supplies the actual phase current to the motor using the reduced requested phase current and using measured phase current of the motor derived from using a single current sense resistor. ## Claims ### Claim 1 A method for operating a delta wound three-phase permanent magnet brushless motor comprising the steps of: a) determining a transition motor speed of the motor in a quadrant of a motor speed versus motor torque curve of the motor above which motor speed continues to increase while motor current/torque decreases wherein actual phase current supplied to the motor can be controlled by a motor controller in a current control modification manner which reduces requested phase current for the motor; b) determining the current control modification manner for a quadrant of the motor speed versus motor torque curve, wherein the motor controller can use the current control modification manner to reduce the requested phase current to control the actual phase current when the motor speed is above the transition motor speed; and c) controlling the motor in a quadrant of the motor speed versus motor torque curve with the motor controller wherein, when the motor has a motor speed above the transition motor speed, the motor controller reduces the requested phase current in the current control modification manner and the motor controller supplies the actual phase current to the motor based upon closed loop control using the reduced requested phase current and using measured phase current of the motor derived from using a single current sense resistor. ### Claim 2 (depends on 1) The method of claim 1, also including step d), wherein step d) includes controlling the motor in a quadrant of the motor speed versus motor torque curve with the motor controller, wherein, when the motor has a motor speed below the transition motor speed, the motor controller supplies the actual phase current to the motor based upon closed loop control using the requested phase current and using the measured phase current. ### Claim 3 (depends on 2) The method of claim 2, also including step e), wherein step e) includes controlling the motor in a quadrant of the motor speed versus motor torque curve with the motor controller, wherein, when the motor has a motor speed equal to the transition motor speed, the motor controller supplies the actual phase current to the motor based upon closed loop control using the reduced requested phase current and using the measured phase current. ### Claim 4 (depends on 2) The method of claim 2, also including step e), wherein step e) includes controlling the motor in a quadrant of the motor speed versus motor torque curve with the motor controller, wherein, when the motor has a motor speed equal to the transition motor speed, the motor controller supplies the actual phase current to the motor based upon closed loop control using the requested phase current and using the measured phase current. ### Claim 5 (depends on 2) The method of claim 2, wherein the quadrant of step d) is the same as the quadrant of step c). ### Claim 6 (depends on 5) The method of claim 5, wherein the quadrant of step c) is the first quadrant. ### Claim 7 (depends on 5) The method of claim 5, wherein the quadrant of step c) is the second quadrant. ### Claim 8 (depends on 5) The method of claim 5, wherein the quadrant of step c) is the third quadrant. ### Claim 9 (depends on 5) The method of claim 5, wherein the quadrant of step c) is the fourth quadrant. ### Claim 10 (depends on 1) The method of claim 1, wherein the quadrant of step c) is the same as the quadrant of step b) and wherein the quadrant of step b) is the same as the quadrant of step a). ### Claim 11 (depends on 10) The method of claim 10, wherein the quadrant of step c) is the second or fourth quadrant but is not the first quadrant and is not the third quadrant. ### Claim 12 (depends on 1) The method of claim 1, wherein the quadrant of step c) is the same as the quadrant of step b) and wherein the quadrant of step c) is different from the quadrant of step a). ### Claim 13 (depends on 12) The method of claim 12, wherein the quadrant of step c) is the second or fourth quadrant but is not the first quadrant and is not the third quadrant. ### Claim 14 (depends on 1) The method of claim 1, wherein the quadrant of step c) is different from the quadrant of step b). ### Claim 15 (depends on 1) The method of claim 1, wherein the motor controller in step c) uses the reduced requested phase current only for a predetermined time substantially immediately following a motor commutation when the motor speed is above the transition motor speed. ### Claim 16 (depends on 1) The method of claim 1, wherein the motor controller in step c) uses the reduced requested phase current continuously when the motor speed is above the transition motor speed. ### Claim 17 (depends on 1) The method of claim 1, wherein the reduced requested phase current is the same for any quadrant for the same requested phase current, the same motor speed, and the same transition motor speed. ### Claim 18 (depends on 1) The method of claim 1, wherein the reduced requested phase current is the same for the second and fourth quadrants for the same requested phase current, the same motor speed, and the same transition motor speed. ### Claim 19 (depends on 1) The method of claim 1, wherein the reduced requested phase current is the same for the first and third quadrants for the same requested phase current, the same motor speed, and the same transition motor speed. ### Claim 20 (depends on 1) The method of claim 1, wherein the reduced requested phase current is different for each quadrant for the same requested phase current, the same motor speed, and the same transition motor speed.