US 10,851,695 B2 · Exhaust gas aftertreatment system for diesel engine and method of detecting abnormal injection

Abstract

Disclosed is an exhaust gas aftertreatment system (1) for a diesel engine, the exhaust gas aftertreatment system comprising: a treatment agent tank (2) for storing an exhaust gas treatment agent; a metering injection module (4), with the injection of the metering injection module (4) being controlled with a determined duty ratio signal according to a desired injection amount; a supply module (3) connected between the treatment agent tank (2) and the metering injection module (4) for supplying the exhaust gas treatment agent to the metering injection module (4); an exhaust gas treatment agent pipe (6) connected between the metering injection module (4) and the supply module (3); a pressure sensor for measuring the system pressure in the exhaust gas treatment agent pipe (6); and a controller (7); wherein the controller (7) is configured to receive a system pressure signal from the pressure sensor during injection of the metering injection module (4), and detect an injection abnormality of the metering injection module (4) based on at least a first amount, which represents an actual injection amount and is determined by the system pressure signal, and a second amount, which represents a theoretical injection amount and is determined by a corresponding duty ratio signal. A corresponding injection abnormality detection method is further disclosed. The injection abnormality detection method is simple and reliable.

Claims10

Dependent claims

An exhaust gas aftertreatment system for a diesel engine, the exhaust gas aftertreatment system comprising:

a treatment agent tank for storing an exhaust gas treatment agent;
a metering injection module, with the injection of the metering injection module being controlled with a determined duty ratio signal at a determined frequency corresponding to a desired injection amount;
a supply module connected between the treatment agent tank and the metering injection module for supplying the exhaust gas treatment agent to the metering injection module;
an exhaust gas treatment agent pipe connected between the metering injection module and the supply module;
a pressure sensor for measuring a system pressure in the exhaust gas treatment agent pipe;
and
a controller, wherein the controller is configured to:
receive a system pressure signal from the pressure sensor during injection of the metering injection module,
determine a frequency domain amplitude of the system pressure signal at the determined frequency of the determined duty ratio signal corresponding to the desired injection amount, and
detect an injection abnormality of the metering injection module based on at least a deviation between a first amount and a second amount,
wherein the first amount represents an actual injection amount and is determined based on the frequency domain amplitude of the system pressure signal at the determined frequency of the determined duty ratio signal corresponding to the desired injection amount, and
wherein the second amount represents the desired injection amount corresponding to the determined ratio signal.

9 more elements

An injection abnormality detection method for an exhaust gas aftertreatment system for a diesel engine, the exhaust gas aftertreatment system including

a treatment agent tank for storing an exhaust gas treatment agent;
a metering injection module, with the injection of the metering injection module being controlled with a determined duty ratio signal according to the desired injection amount;
a supply module connected between the treatment agent tank and the metering injection module for supplying the exhaust gas treatment agent to the metering injection module;
an exhaust gas treatment agent pipe connected between the metering injection module and the supply module;
a pressure sensor for measuring the system pressure in the exhaust gas treatment agent pipe;
and
a controller, and
the method comprising:
receiving a system pressure signal from the pressure sensor;
determining a frequency of the determined duty ratio signal corresponding to the desired injection amount applied to the metering injection module during injection;
determining a frequency domain amplitude of the system pressure signal at the determined frequency of the determined duty ratio signal corresponding to the desired injection amount;
and
detecting, by the controller, an injection abnormality of the metering injection module at least based on a deviation between a first amount and a second amount,
wherein the first amount represents an actual injection amount and is determined based on the frequency domain amplitude of the system pressure signal at the determined frequency of the determined duty ratio signal corresponding to the desired injection amount, and
wherein the second amount represents the desired injection amount corresponding to the determined duty ratio signal.

12 more elements

Dependencies are inferred from the claim text.

Exhaust gas aftertreatment system for diesel engine and method of detecting abnormal injection

Life of this patent

Exhaust gas aftertreatment system for diesel engine and method of detecting abnormal injection

Life of this patent

Abstract

Claims10