Patent ID: 11913506
Assignee: ZF FRIEDRICHSHAFEN AG
Field: Mechanical elements (Mechanical engineering)
Classification: CPC F  B | IPC F

Claim 11:
12. A vehicle transmission, comprising:
a clutch;
a hydraulic circuit;
a valve configured to set a defined pressure in the hydraulic circuit as a function of a control current (i_Endstufe) in order to selectively actuate the clutch; and
a control unit configured to determine the control current (i_Endstufe), the control unit configured for
obtaining (20) a target pressure specification (p_Soll) that represents a desired target pressure in the hydraulic circuit,
converting (26) the target pressure specification (p_Soll) into a target volume flow rate (Q_soll),
determining (42) a valve volume flow rate (Q_Ventil) as a function of the target volume flow rate (Q_soll) and as a function of parameters that represent system properties (P_SysLim) of the hydraulic circuit, wherein the valve volume flow rate (Q_Ventil) represents a volume flow rate through the valve,
determining (46) a pressure drop at the valve due to flow forces as a function of the valve volume flow rate (Q_Ventil),
determining (48) a compensated valve output pressure (p_VentilSoll) as a function of the valve volume flow rate (Q_Ventil) and the pressure drop,
determining (58) the electric control current (i_Endstufe) as a function of the compensated valve output pressure (p_VentSoll), and
activating the valve with the electric control current (i_Endstufe).