US 12,132,425 B2
Motor drive system and torque distribution method thereof
Chih-Hung Hsiao, Taoyuan (TW); Chung-Hsing Ku, Taoyuan (TW); Shang-Wei Chiu, Taoyuan (TW); and Zhi-Sheng Yang, Taoyuan (TW)
Assigned to Delta Electronics, Inc., Taoyuan (TW)
Filed by Delta Electronics, Inc., Taoyuan (TW)
Filed on Dec. 2, 2022, as Appl. No. 18/074,276.
Claims priority of application No. 202211085694.4 (CN), filed on Sep. 6, 2022.
Prior Publication US 2024/0079981 A1, Mar. 7, 2024
Int. Cl. H02P 21/22 (2016.01); H02P 21/20 (2016.01)
CPC H02P 21/22 (2016.02) [H02P 21/20 (2016.02)] 26 Claims
OG exemplary drawing
 
1. A motor drive system, comprising:
an electric motor;
a drive circuit for converting an input power into a driving current, wherein the driving current is provided to the electric motor to drive the electric motor; and
a control unit receiving a torque command, and comprising a current command generator, wherein the current command generator generates a current command according to the torque command and a motor operating information of the electric motor, and the current command contains a d-axis current command and/or a q-axis current command, wherein the driving current is converted into a d-axis current and/or a q-axis current by the control unit through coordinate conversion, and the drive circuit is controlled by the control circuit, so that the driving current is close to the d-axis current command and/or the q-axis current command corresponding to the current command,
wherein the current command generator contains a maximum torque per ampere (MTPA) lookup table and a zero recycle lookup table, wherein the MTPA lookup table is a lookup table about a relationship between the torque command and the current command according to the motor operating information when a consumed power of the electric motor is the lowest, and the zero recycle lookup table is a lookup table about a relationship between the torque command and the current command according to the motor operating information when the consumed power of the electric motor and a recycling power of the electric motor are offset,
wherein if a value of the torque command is positive, the current command generator generates the corresponding current command according to the MTPA lookup table,
wherein if the value of the torque command is negative, the current command generator generates the corresponding current command according to the zero recycle lookup table.