A rotary electric machine, comprising: a stator with a stator winding; a rotor with a field winding supported for rotation about a rotation axis relative to the stator, the rotor defining a coolant channel having an inlet and an outlet; and an excitation winding fixed relative to the rotor and electrically connected to the field winding, wherein liquid coolant that enters the inlet flows outwardly through a portion of the excitation winding to conduct heat away from the excitation winding; wherein: the liquid coolant is a dielectric liquid coolant; and the rotor comprises an end plate fixed in rotation relative to the rotor, the end plate arranged axially between the excitation winding and the field winding; wherein the end plate defines: a radially outer segment extending between the excitation winding and the field winding; and characterized in that the end plate further defines: a coolant channel radially inner segment extending between the rotation axis and the excitation winding, the coolant channel radially inner segment fluidly terminating at the excitation winding; and a coolant channel radially outer segment extending between the excitation winding and the field winding, the excitation winding is fluidly interposed between the coolant channel radially outer segment and the rotation axis; wherein the coolant channel radially outer segment extends at least partially about the rotation axis with a circumferential component; and wherein an end turn pocket is defined on an axial face of the end plate, wherein an end turn of the excitation winding is fixed within the end turn pocket, the end turn pocket fluidly coupling the excitation winding end turn to the coolant channel radially inner and outer segments. a stator with a stator winding; a rotor with a field winding supported for rotation about a rotation axis relative to the stator, the rotor defining a coolant channel having an inlet and an outlet; and an excitation winding fixed relative to the rotor and electrically connected to the field winding, wherein liquid coolant that enters the inlet flows outwardly through a portion of the excitation winding to conduct heat away from the excitation winding; wherein: the liquid coolant is a dielectric liquid coolant; and the rotor comprises an end plate fixed in rotation relative to the rotor, the end plate arranged axially between the excitation winding and the field winding; wherein the end plate defines: a radially outer segment extending between the excitation winding and the field winding; the liquid coolant is a dielectric liquid coolant; and the rotor comprises an end plate fixed in rotation relative to the rotor, the end plate arranged axially between the excitation winding and the field winding; wherein the end plate defines: a radially outer segment extending between the excitation winding and the field winding; a radially outer segment extending between the excitation winding and the field winding; a coolant channel radially inner segment extending between the rotation axis and the excitation winding, the coolant channel radially inner segment fluidly terminating at the excitation winding; and a coolant channel radially outer segment extending between the excitation winding and the field winding, the excitation winding is fluidly interposed between the coolant channel radially outer segment and the rotation axis; wherein the coolant channel radially outer segment extends at least partially about the rotation axis with a circumferential component; and wherein an end turn pocket is defined on an axial face of the end plate, wherein an end turn of the excitation winding is fixed within the end turn pocket, the end turn pocket fluidly coupling the excitation winding end turn to the coolant channel radially inner and outer segments.