Method for controlling and regulating an internal combustion engine
Proposed is a method for controlling and regulating an internal combustion engine ( 1 ) having a common rail system and having a passive pressure limiting valve ( 11 ) for discharging fuel out of a rail ( 6 ) into the fuel tank ( 2 ), in which method, in a first stage, the pressure limiting valve ( 11 ) is set as open when the rail pressure, proceeding from a steady-state rail pressure, exceeds a first threshold value and subsequently falls below a second threshold value within a first critical time, wherein the first threshold value characterizes a higher pressure level than the steady-state rail pressure and the second threshold value characterizes a lower pressure level than the first threshold value, and in which method the opening duration of the opened pressure limiting valve ( 11 ) is monitored.
1. Method for controlling and regulating an internal combustion engine having a common rail system and having a passive pressure limiting valve for discharging fuel out of a rail into the fuel tank, in which method in a first stage, the pressure limiting valve is then set as open if, within a first critical time, proceeding from a steady-state rail pressure, the rail pressure exceeds a first threshold value and subsequently falls below a second threshold value, wherein the first threshold value characterizes a higher pressure level than the steady-state rail pressure, and the second threshold value characterizes a lower pressure level than the first threshold value, and in which method the opening duration of the pressure limiting valve is monitored.
2. Method according to claim 1
characterized in that
the opening duration is monitored in that a first time limit is determined by setting an open pressure limiting valve, and a second time limit determined for further operation, upon timeout of the first time limit, a yellow alarm for warning the operator is initiated, and after timeout of the second time limit, a red alarm is initiated as a recommendation to replace the pressure limiting valve.
3. Method according to claim 2 ,
characterized in that
the first critical time is set upon exceeding the first threshold value.
4. Method according to claim 3
characterized in that
the opening duration is stored upon detecting a stopped internal combustion engine.
5. Method according to claim 4
characterized in that
after a restart of the internal combustion engine, the saved opening duration continues to be counted, if the pressure limiting valve is again set as open during normal operation and the opening duration of the pressure limiting valve is monitored.
6. Method according to claim 1
characterized in that
the pressure limiting valve is set as open if, after a positively detected first stage, an absolute value of the rail pressure control deviation greater than/equal to a threshold value is detected without interruption within a second critical time in a second stage.
7. Method according to claim 1 or 6 ,
characterized in that
the frequency of the opening procedures is also detected supplementally to monitoring the opening duration.
8. Method according to claim 7 ,
characterized in that
a yellow alarm is initiated for a first number of opening procedures, and
a red alarm is initiated for a second number of opening procedures.
9. Method according to claim 1 , wherein the second threshold value is a lower pressure level than the steady-state rail pressure.
10. Method according to claim 1 , further comprising providing a handling recommendation regarding the pressure limiting valve from the opening duration of the pressure limiting valve.
11. Method according to claim 10 , further comprising:
receiving an indication of a restart of the internal combustion engine; and
determining the handling recommendation based upon at least a saved opening duration of the pressure limiting valve occurring prior to the restart of the internal combustion engine.
12. Method according to claim 10 , wherein the handling recommendation includes one of a warning and a replacement recommendation.
13. A method of controlling an internal combustion engine having a common rail system and having a passive pressure limiting valve for discharging fuel out of a rail into the fuel tank, the method comprising:
setting the pressure limiting valve as open if, within a first time period, the rail pressure increases from a steady-state rail pressure and exceeds a first threshold value, and subsequently falls below a second threshold value, wherein the second threshold value is a lower pressure level than the first threshold value, and
monitoring an opening duration of the pressure limiting valve.
14. The method of claim 13 , wherein the second threshold value is a lower pressure level than the steady-state rail pressure.
15. The method of claim 13 , further comprising providing a handling recommendation regarding the pressure limiting valve from the opening duration of the pressure limiting valve.
16. The method of claim 15 , further comprising:
receiving an indication of a restart of the internal combustion engine; and
determining the handling recommendation based upon at least a saved opening duration of the pressure limiting valve occurring prior to the restart of the internal combustion engine.
17. The method of claim 15 , wherein the handling recommendation includes one of a warning and a replacement recommendation.