US 12,395,107 B2
Electric motor
Masashi Kubota, Kariya (JP); Takuya Naruse, Kariya (JP); and Takashi Kawashima, Kariya (JP)
Assigned to KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, Aichi-Ken (JP)
Filed by KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, Aichi-ken (JP)
Filed on Nov. 8, 2023, as Appl. No. 18/504,262.
Claims priority of application No. 2022-182583 (JP), filed on Nov. 15, 2022.
Prior Publication US 2024/0171102 A1, May 23, 2024
Int. Cl. H02P 21/18 (2016.01)
CPC H02P 21/18 (2016.02) 3 Claims
OG exemplary drawing
 
1. An electric motor, comprising:
a motor unit including a rotor, a stator, and three-phase coils wound around the stator;
an inverter unit including a driver and a switching element driven by the driver, the inverter unit being configured to drive the motor unit when the switching element is driven;
an output voltage detector configured to detect an output voltage of the inverter unit; and
processing circuitry configured to calculate command values and control the switching element, the command values being used to control the switching element, wherein
the processing circuitry is configured to estimate the position of the rotor in a mode selected from an induced voltage mode and a harmonic superimposition mode,
the induced voltage mode is a mode of estimating the position of the rotor based on an induced voltage that is generated in the three-phase coils,
the harmonic superimposition mode is a mode of estimating the position of the rotor by superimposing a harmonic on each of the command values, and
the processing circuitry is configured to:
estimate the position of the rotor using the induced voltage mode when the output voltage is greater than or equal to a predetermined threshold value; and
estimate the position of the rotor using the harmonic superimposition mode when the output voltage is less than the threshold value.