US 12,424,963 B2
Motor vehicle having an externally excited synchronous machine
Daniel Ruppert, Lenting (DE)
Assigned to Audi AG, Ingolstadt (DE)
Filed by AUDI AG, Ingolstadt (DE)
Filed on Jul. 25, 2023, as Appl. No. 18/358,863.
Claims priority of application No. 102022118619.9 (DE), filed on Jul. 26, 2022.
Prior Publication US 2024/0039449 A1, Feb. 1, 2024
Int. Cl. H02H 7/09 (2006.01); H02K 11/33 (2016.01); H02P 29/024 (2016.01)
CPC H02P 29/0241 (2016.02) [H02K 11/33 (2016.01)] 11 Claims
OG exemplary drawing
 
1. A motor vehicle, comprising:
an externally excited synchronous machine;
an inverter associated with the synchronous machine and connected to a voltage network;
an exciter circuit which, in operation, energizes an exciter winding of the synchronous machine;
a power electronics layout having at least one intermediate circuit capacitor at a side of the voltage network;
a cooling device which, in operation, cools the power electronics layout; and
a voltage surge protection circuit associated with the at least one intermediate circuit capacitor and including at least one varistor which, in operation, becomes electrically conducting by a voltage imposed on the at least one varistor when a voltage threshold value is exceeded,
wherein the at least one varistor of the voltage surge protection circuit forms part of an exciter module including the exciter circuit and a housing,
wherein the housing is thermally coupled to a cooling element of the cooling device, and
wherein the at least one varistor includes at least two varistors switched in series in one varistor branch or in at least two parallel varistor branches each having at least one of the at least two varistors.