US 11,990,852 B2
Control device for electric motor
Akira Ide, Aichi-ken (JP)
Assigned to KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, Kariya (JP)
Appl. No. 17/783,789
Filed by KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, Kariya (JP)
PCT Filed Nov. 19, 2020, PCT No. PCT/JP2020/043160
§ 371(c)(1), (2) Date Jun. 9, 2022,
PCT Pub. No. WO2021/117453, PCT Pub. Date Jun. 17, 2021.
Claims priority of application No. 2019-225345 (JP), filed on Dec. 13, 2019.
Prior Publication US 2023/0011035 A1, Jan. 12, 2023
Int. Cl. H02P 21/22 (2016.01)
CPC H02P 21/22 (2016.02) 2 Claims
OG exemplary drawing
 
1. A control device for an electric motor, the control device comprising:
an inverter circuit that drives the electric motor with a plurality of switching elements turned on and off; and
a control circuit that converts an alternating current that flows through the electric motor to a d-axis current and a q-axis current, finds a voltage command value such that the d-axis current and the q-axis current approach a d-axis current command value and a q-axis current command value, respectively, and turns the plurality of switching elements on and off by using a drive signal in accordance with a result of comparison between the voltage command value and a carrier wave,
wherein the control circuit corrects the voltage command value by using a polarity of the alternating current during dead time in which the switching elements connected to each other in series are prohibited from being simultaneously turned on, and causes the d-axis current command value in a certain length of time before and after the alternating current reaches zero to be greater than the d-axis current command value in a length of time other than the certain length of time.