	US 11,742,727 B2
	Method and device for determining a rotor temperature value for an electric motor
Franz Prenner, Friedrichshafen (DE); and Oussama Jabloun, Friedrichshafen (DE)
Assigned to ZF Friedrichshafen AG, Friedrichshafen (DE)
Filed by ZF Friedrichshafen AG, Friedrichshafen (DE)
Filed on Mar. 17, 2022, as Appl. No. 17/696,996.
Claims priority of application No. 10 2021 202 982.5 (DE), filed on Mar. 26, 2021.
Prior Publication US 2022/0311313 A1, Sep. 29, 2022
Int. Cl. H02K 11/25 (2016.01); H02K 11/27 (2016.01); G01K 7/42 (2006.01); H02P 29/60 (2016.01)

CPC H02K 11/25 (2016.01) [G01K 7/42 (2013.01); H02K 11/27 (2016.01); H02P 29/60 (2016.02); G01K 2205/00 (2013.01)]

13 Claims

1. A method for determining a rotor temperature value (T_rot) for an electric machine, wherein the method comprises:

calculating a support value (P_{cu2_Trot}) using a rotor temperature value (T_rot) determined with a temperature model, and a motor current value (I_sdq);

determining an auxiliary value (P_{cu2_Ref}) using a motor torque (T_rq) and a motor slip value (ω_slip);

linking of the support value (P_{cu2_Trot}) with the auxiliary value (P_{cu2_Ref}) in order to obtain a corrected temperature value (Delta_Trot);

modifying the temperature model, using the corrected temperature value (Delta_Trot) in order to obtain a corrected temperature model; and

determining the rotor temperature value (T_rot) using the corrected temperature model.