Method and an apparatus for controlling glow plugs in a diesel engine, particularly for motor-vehicles

Abstract

A method is provided for controlling a glow plug (GP) associated with a cylinder chamber of a Diesel engine. The method includes, but is not limited to the steps of driving in an on-off manner in a period of time an electronic switch (M) connected essentially in series with the glow plug (GP) between the terminals of a d.c. voltage supply (B), sensing the voltage (V) across the glow plug (GP) and the current (I) flowing through the glow plug (GP) and performing a voltage closed loop control for controlling the temperature of the glow plug (GP). The method further includes, but is not limited to the steps of calculating a normalized current error (εI) as a function of said sensed current (I), calculating a normalized voltage error (εV) as a function of said sensed voltage (V), calculating a weight function (K) as a function of predetermined parameters (α, β, n) and calculating a global error (ε) as a function of said normalized current error (εI), normalized voltage error (εV) and weight function (K). Finally, the method includes, but is not limited to the step of combining the voltage closed loop control with a current closed loop control according to the value of said global error (ε).

Dependencies are inferred from the claim text.