US 12,418,081 B2
Device and method for measuring the temperature of a cooling medium for an inverter, inverter with such a device
Navid Daniali, Pegnitz (DE); and Johannes Hager, Marktleugast (DE)
Assigned to ZF Friedrichshafen AG, Friedrichshafen (DE)
Filed by ZF Friedrichshafen AG, Friedrichshafen (DE)
Filed on Oct. 28, 2021, as Appl. No. 17/512,934.
Claims priority of application No. 102020213626.2 (DE), filed on Oct. 29, 2020.
Prior Publication US 2022/0140455 A1, May 5, 2022
Int. Cl. H01M 50/569 (2021.01); B60W 20/20 (2016.01); H01M 50/519 (2021.01)
CPC H01M 50/569 (2021.01) [H01M 50/519 (2021.01); B60W 20/20 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A method for measuring a temperature of a coolant flowing through a heatsink in a power module to ensure a cooling function of the heatsink, wherein temperature sensors are not placed in direct contact with the coolant in proximity to the power module, and wherein a first temperature sensor for measuring a first temperature and a second temperature sensor for measuring a second temperature are located in the power module and not in direct contact with the coolant, the method comprising:
calculating a difference between the first temperature and second temperature;
determining one or more thermal resistances and one or more thermal capacitances with a thermal circuit corresponding to the power module, based on the calculated difference, and based on at least one power loss in the power module, wherein the thermal circuit comprises at least one thermal network comprising at least one Foster network and/or at least one Cauer network, and wherein the one or more thermal resistances and the one or more thermal capacitances are determined by solving an equation system formed by discreet differential equations for the at least one thermal network and operating point information; and
determining the temperature of the coolant based on a difference between at least one of the first temperature and the second temperature and a delta-temperature that is based on the one or more thermal resistances, the one or more thermal capacitances, and the at least one power loss.