| 摘要 |
The temperature of the particle filter is monitored and the speed of burning is reduced or combustion extinguished by reducing the oxygen concentration in the exhaust gases upstream of the filter when the temperature and/or the temperature gradient passes a first threshold value. The value of lambda is held between 1.05 and 1.4, in particular between 1.1 and 1.3, as a function of the difference between the measured and threshold temperatures of the filter and/or the difference between the measured and threshold temperature gradients. The inlet pressure is reduced and/or the AGR rate is increased. Lambda is controlled using a throttle in the air inlet and/or by the quantity of the principal injection. The burning of the particles is interrupted by reduction in the value of lambda below 1.02, when the temperature of the particle filter reaches a second temperature threshold (S2) above the first temperature threshold (S1). This reduction is obtained by post-injection or throttling, so the air ratio is held with lambda between 0.95 and 0.99. Reduction of lambda below 1.02 is achieved by throttling the diesel engine. Particle burning is restarted when the temperature drops below the second threshold value by a predetermined hysteresis. An Independent claim is included for a device for carrying out the above process, comprising a diesel engine, a particle filter downstream of the engine, an engine controller, and a temperature detector which measures temperature in or downstream of the filter. |
