초록 ▼

This system, in which the engine is associated with a turbocharger and with a feed device adapted to implement first and second regeneration strategies depending on different engine operation control parameters to obtain different temperatures in the exhaust line, acquires the temperature in the lin

This system, in which the engine is associated with a turbocharger and with a feed device adapted to implement first and second regeneration strategies depending on different engine operation control parameters to obtain different temperatures in the exhaust line, acquires the temperature in the line, compares it with a safety threshold for the turbocharger turbine so that if the threshold is exceeded while applying the second strategy, the feed device is controlled so that one of the engine operation control parameters is regulated to reduce the temperature, and if it does not drop back below the threshold at the end of a first time period, the feed device is controlled to switch over to the first strategy, and if it still does not drop back below the threshold at the end of a second time period, the feed device is controlled to stop the regeneration strategy.

대표청구항 ▼

The invention claimed is: 1. A system for assisting the regeneration of depollution means integrated in an exhaust line of a motor vehicle diesel engine, in which the engine is associated with a turbocharger and with common rail feed means for injecting fuel into the cylinders of the engine in at l

The invention claimed is: 1. A system for assisting the regeneration of depollution means integrated in an exhaust line of a motor vehicle diesel engine, in which the engine is associated with a turbocharger and with common rail feed means for injecting fuel into the cylinders of the engine in at least one post-injection, and adapted to implement, at constant torque, at least two regeneration strategies at a first level and at a second level, depending on different engine operation control parameters, in order to obtain different temperature levels in the exhaust line, the temperature level corresponding to the second level strategy being higher than the temperature level corresponding to the first level, the system including acquisition means for acquiring the temperature level in the exhaust line, comparator means for comparing said temperature level with a safety threshold value for the turbine of the turbocharger so that in the event of said threshold value being exceeded while applying the second level strategy, the feed means are controlled so as to regulate at least one of the engine operation control parameters progressively so as to reduce the temperature level in the exhaust line, and if said temperature level does not drop below the threshold value at the end of a predetermined first time period, the feed means are controlled to switch over to the first level strategy, and if the temperature level in the exhaust line still does not drop below the safety threshold value at the end of a second time period, the feed means are controlled to stop the regeneration strategy. 2. The system according to claim 1, wherein the feed means are adapted to implement two successive post-injections. 3. The system according to claim 2, wherein during regulation, the feed means are adapted to reduce progressively the flow rate of fuel during the second post-injection. 4. The system according to claim 3, wherein the feed means are adapted to reduce the flow rate of the second post-injection by using a correction factor lying in the range 0 to 1 and determined on the basis of the difference between the temperature level acquired from the exhaust line and the safety threshold value. 5. The system according to claim 4, wherein the correction factor is determined by a PI type regulator having non-linear gain. 6. The system according to claim 1, wherein the temperature level acquisition means comprise at least one temperature sensor. 7. The system according to claim 1, wherein the safety threshold value is calibratable. 8. The system according to claim 1, wherein the depollution means comprise a particle filter. 9. The system according to claim 1, wherein the depollution means comprise a NOx trap. 10. The system according to claim 1, wherein the depollution means comprise a SOx trap. 11. The system according to claim 1, wherein the depollution means comprise an oxidation catalyst. 12. The system according to claim 1, wherein the fuel includes an additive for being deposited, together with the particles with which it is mixed, on the depollution means in order to facilitate regeneration thereof. 13. The system according to claim 1, wherein the fuel includes an additive forming a NOx trap.