US 12,294,315 B2
Inverter device, and vehicular electric compressor provided with same
Atsushi Saito, Isesaki (JP)
Assigned to SANDEN CORPORATION, Isesaki (JP)
Appl. No. 18/040,225
Filed by SANDEN CORPORATION, Isesaki (JP)
PCT Filed Aug. 24, 2021, PCT No. PCT/JP2021/030910
§ 371(c)(1), (2) Date Feb. 1, 2023,
PCT Pub. No. WO2022/045098, PCT Pub. Date Mar. 3, 2022.
Claims priority of application No. 2020-141410 (JP), filed on Aug. 25, 2020.
Prior Publication US 2023/0327577 A1, Oct. 12, 2023
Int. Cl. H02M 7/5387 (2007.01); H02M 1/32 (2007.01); H02M 7/48 (2007.01); H02M 1/00 (2006.01)
CPC H02M 7/53871 (2013.01) [H02M 1/327 (2021.05); H02M 7/48 (2013.01); H02M 1/0009 (2021.05)] 17 Claims
OG exemplary drawing
 
10. A vehicular electric compressor comprising:
an inverter device including an inverter circuit having at least one power semiconductor element, and an inverter control unit to drive the at least one power semiconductor element;
a motor operated by the inverter device; and
a housing in which the motor is accommodated,
wherein the at least one power semiconductor element is arranged in a heat exchange relationship with a suction refrigerant via the housing,
wherein the vehicular electric compressor includes a temperature detector to detect a temperature in the vicinity of the at least one power semiconductor element,
wherein the inverter control unit includes:
a loss calculating unit to calculate a loss P of the at least one power semiconductor element, and
a junction temperature estimate calculating unit to adds a temperature rise value ΔT obtained from the loss P of the at least one power semiconductor element calculated by the loss calculating unit to the temperature Tth detected by the temperature detector to estimate a junction temperature Tj of the at least one power semiconductor element,
wherein when estimating the junction temperature Tj, the junction temperature estimate calculating unit corrects the junction temperature Tj in a direction of being lowered as a number of revolutions of the motor becomes higher, and
wherein the junction temperature estimate calculating unit multiplies the loss P of the at least one power semiconductor element by a predetermined thermal variable α to calculate the temperature rise value ΔT and changes the thermal variable α so that the thermal variable α becomes smaller as the number of revolutions of the motor becomes higher.