Control device, engine, and control method of engine

A control device including a processor and configured to be able to execute, in an engine which includes a DOC disposed in an exhaust passage of the engine, a DPF disposed downstream of the DOC in the exhaust passage, and a temperature increase unit for increasing a temperature of each of the DOC and the DPF, a forced regeneration process of removing PM deposited on the DPF by increasing the temperature of the DPF,

• wherein the temperature increase unit includes an exhaust throttle valve disposed in the exhaust passage,
• wherein the control device comprises:
• a flow rate estimation part configured to estimate an intake flow rate of a combustion gas sent into a cylinder of the engine,
• wherein the flow rate estimation part is:
• configured to estimate a first intake flow rate, which is the intake flow rate in the forced regeneration process, from an opening degree of the exhaust throttle valve and a first state amount which indicates an operation state of the engine including a rotation speed of the engine, based on a first relationship representing a relationship between the first intake flow rate, and the opening degree of the exhaust throttle valve and the first state amount, in the forced regeneration process,
• wherein the flow rate estimation part is:
• configured to estimate a second intake flow rate, which is the intake flow rate in a normal operation where the forced regeneration process is not executed, from a second state amount which indicates an operation state of the engine including the rotation speed of the engine and a fuel injection amount, based on a second relationship representing a relationship between the second state amount and the second intake flow rate, in the normal operation,
• a PM deposition amount estimation part configured to be able to estimate a deposition amount of the PM deposited on the DPF;
• and
• a first intake flow rate correction part configured to decrease the first intake flow rate, which is estimated by the flow rate estimation part, in accordance with a first correction value, which is a correction value of the first intake flow rate and is estimated from the PM deposition amount estimated by the PM deposition amount estimation part, based on a fourth relationship representing a relationship between the first correction value and the PM deposition amount estimated by the PM deposition amount estimation part.

A control device including a processor and configured to be able to execute, in an engine which includes a DOC disposed in an exhaust passage of the engine, a DPF disposed downstream of the DOC in the exhaust passage, and a temperature increase unit for increasing a temperature of each of the DOC and the DPF, a forced regeneration process of removing PM deposited on the DPF by increasing the temperature of the DPF,

• wherein the temperature increase unit includes an exhaust throttle valve disposed in the exhaust passage,
• wherein the control device comprises:
• a flow rate estimation part configured to estimate an intake flow rate of a combustion gas sent into a cylinder of the engine,
• wherein the flow rate estimation part is:
• configured to estimate a first intake flow rat e, which is the intake flow rate in the forced regeneration process, from an opening degree of the exhaust throttle valve and a first state amount which indicates an operation state of the engine including a rotation speed of the engine, based on a first relationship representing a relationship between the first intake flow rate, and the opening degree of the exhaust throttle valve and the first state amount, in the forced regeneration process,
• wherein the flow rate estimation part is:
• configured to estimate a second intake flow rate, which is the intake flow rate in a normal operation where the forced regeneration process is not executed, from a second state amount which indicates an operation state of the engine including the rotation speed of the engine and a fuel injection amount, based on a second relationship representing a relationship between the second state amount and the second intake flow rate, in the normal operation,
• a PM deposition amount estimation part configured to be able to estimate a deposition amount of the PM deposited on the DPF;
• and
• a second intake flow rate correction part configured to decrease the second intake flow rate, which is estimated by the flow rate estimation part, in accordance with a second correction value, which is a correction value of the second intake flow rate and is estimated from the PM deposition amount estimated by the PM deposition amount estimation part, based on a fifth relationship representing a relationship between the second correction value and the PM deposition amount estimated by the PM deposition amount estimation part.

A control device including a processor and configured to be able to execute, in an engine which includes a DOC disposed in an exhaust passage of the engine, a DPF disposed downstream of the DOC in the exhaust passage, and a temperature increase unit for increasing a temperature of each of the DOC and the DPF, a forced regeneration process of removing PM deposited on the DPF by increasing the temperature of the DPF,

• wherein the temperature increase unit includes an exhaust throttle valve disposed in the exhaust passage,
• wherein the control device comprises:
• a flow rate estimation part configured to estimate an intake flow rate of a combustion gas sent into a cylinder of the engine,
• wherein the flow rate estimation part is:
• configured to estimate a first intake flow rate, which is the intake flow rate in the forced regeneration process, from an opening degree of the exhaust throttle valve and a first state amount which indicates an operation state of the engine including a rotation speed of the engine, based on a first relationship representing a relationship between the first intake flow rate, and the opening degree of the exhaust throttle valve and the first state amount, in the forced regeneration process,
• wherein the engine further includes an atmospheric pressure sensor configured to acquire an atmospheric pressure value, and
• wherein the control device further comprises:
• a third intake flow rate correction part configured to increase/decrease the intake flow rate, which is estimated by the flow rate estimation part, in accordance with a third correction value, which is a correction value of the intake flow rate and is estimated from the atmospheric pressure value acquired by the atmospheric pressure acquisition device, based on a sixth relationship representing a relationship between the third correction value and the atmospheric pressure value acquired by the atmospheric pressure acquisition device.