Patent ID: 11926221
Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
Field: Transport (Mechanical engineering)
Classification: CPC B  H  Y | IPC B  H

Claim 18:
19. A method for controlling transient operation of a permanent magnet (PM) machine, the method comprising:
during operation of the PM machine in a maximum torque per ampere (MTPA) control region, receiving a commanded temperature and a measured temperature of the PM;
calculating, via a controller using the commanded temperature, the measured temperature, a commanded d-axis current, and a commanded q-axis current, a d-axis delta current (ΔId) term and a q-axis delta current (ΔIq) term required to maintain an output torque level of the PM machine through a change of temperature of the PM machine in the MTPA region;
providing a direct current bus voltage, a torque slew command, and a rotary speed of the PM into separate d-axis and q-axis current command lookup tables;
determining the Id term and the Iq term via the separate d-axis and q-axis current command lookup tables using the direct current bus voltage, the torque slew command, and the rotary speed; and
applying the required ΔId term and the required ΔId term as feed-forward terms to respectively adjust the Id term and the Iq term, thereby maintaining the output torque level of the PM machine during a shunt angle transition, the shunt angle transition occurring over a transient response time corresponding with a back-EMF of the PM machine varying while shunting elements embedded thereon change positions.