A method for controlling a valve control system with variable valve lift of an internal combustion engine by operating a compensation in response to the deviation of the characteristics of a working fluid with respect to nominal conditions

摘要

Described herein is a method for controlling a valve-control system (1) for variable-lift actuation of the valves (2) of a reciprocating internal-combustion engine, wherein the valve-control system (1) comprises, for each cylinder of said reciprocating internal-combustion engine, a solenoid valve (11) for controlling the flow of a hydraulic fluid in said valve-control system (11), and further comprises means configured for determining a real temperature value (T_OIL,AC, T_OIL,SV) of said hydraulic fluid.;The method comprises the steps of:- determining a deviation of performance (CU_AVG_DEV%) of the solenoid valves (11) of said reciprocating internal-combustion engine due to a degradation of the characteristics of said hydraulic fluid with respect to nominal values thereof; and- substituting for said real temperature value (T_OIL,AC, T_OIL,SV) an equivalent temperature value (T_OIL,EQ, T_OIL,SV*) consisting of a temperature value at which the hydraulic fluid having nominal characteristics would produce performance of the solenoid valves (11) corresponding to the performance resulting from the aforesaid deviation so that each solenoid valve (11) is governed as a function of said equivalent temperature value (T_OIL,EQ, T_OIL,SV*) instead of as a function of the real temperature value (T_OIL,AC, T_OIL,SV) of the hydraulic fluid.