Mitsubishi Heavy Industries Engine & Turbocharger, Ltd.

Mizuki Kanai

Kazuki Nishizawa

Tomohide Yamada

Kazutoshi Nomura

Daisuke Sato

Ryuji Kita

A regeneration control apparatus for controlling, in an exhaust gas treatment apparatus of a diesel engine including a diesel oxidation catalyst (DOC) disposed in an exhaust passage of an internal combustion engine and a diesel particulate filter (DPF) disposed downstream of the DOC, execution of forced regeneration to remove an exhaust particulate matter (PM) which accumulates on the DPF through a temperature increase of the DPF, includes: a late-post injection amount determination part which determines a late-post injection amount. The late-post injection amount determination part is configured to determine an upper limit value of the late-post injection amount on the basis of an air excess ratio of exhaust gas flowing into the DOC obtained on the basis of a temperature index of the DOC.

Regeneration control apparatus

A control device is configured to direct an opening degree of a throttle valve disposed in an intake passage or an exhaust passage of an engine including a DOC disposed in the exhaust passage and a DPF disposed downstream of the DOC in the exhaust passage. The control device includes: a hysteresis occurring condition determination unit configured to determine whether a hysteresis occurring condition (predetermined time elapses after instructed opening degree of throttle valve becomes equal to or smaller than predetermined opening degree and/or predetermined time elapses after engine output becomes equal to or smaller than predetermined output) is met; and a hysteresis elimination execution unit configured to cause, if it is determined that the hysteresis occurring condition is met, the throttle valve to execute hysteresis elimination that involves temporarily increasing the opening degree of the throttle valve from the instructed opening degree and then returning it to the instructed opening degree.

Control device, exhaust gas purification system, and control method

Provided is a control device configured to be able to execute a forced regeneration process in an engine which includes a DOC and DPF disposed in an exhaust passage of the engine, and a temperature increase unit including an exhaust throttle valve, for increasing a temperature of each of the DOC and the DPF. The forced regeneration process includes a first temperature increase process of controlling the temperature increase unit such that the temperature of the DOC is increased to a first temperature, and a second temperature increase process of controlling the temperature increase unit such that the temperature of the DPF is increased to a second temperature which is higher than the first temperature after completion of the first temperature increase process. The control device includes a valve opening/closing operation execution part configured to cause the exhaust throttle valve to execute a valve opening/closing operation of increasing an opening degree of the exhaust throttle valve to be greater than a predetermined opening degree for a predetermined time, when the forced regeneration process is switched from the first temperature increase process to the second temperature increase process.

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Sagamihara, Japan

Mizuki Kanai