Exhaust purification system of internal combustion engine

An exhaust purification system of an internal combustion engine, comprising:

• a filter trapping particulate matter in exhaust gas flowing through an exhaust passage of the internal combustion engine and supporting a three-way catalyst;
• and
• an electronic control unit, wherein
• the electronic control unit is configured to perform regeneration processing for oxidizing and removing particulate matter deposited on the filter, calculate an amount of particulate matter deposited on the filter, perform the regeneration processing by supplying NO to the filter, and calculate the amount of particulate matter deposited based on a NOx concentration or a CO concentration in exhaust gas flowing into the filter when the regeneration processing is being performed or a NOx concentration or a CO concentration in exhaust gas flowing out from the filter when the regeneration processing is being performed.

An exhaust purification system of an internal combustion engine, comprising:

• a filter trapping particulate matter in exhaust gas flowing through an exhaust passage of the internal combustion engine and supporting a three-way catalyst;
• and
• an electronic control unit, wherein
• the electronic control unit is configured to perform regeneration processing for oxidizing and removing particulate matter deposited on the filter, calculate a degree of deterioration of the three-way catalyst, perform the regeneration processing by supplying NO to the filter, and calculate the degree of deterioration of the three-way catalyst based on both a NOx concentration in exhaust gas flowing into the filter when the regeneration processing is being performed and a NOx concentration in exhaust gas flowing out from the filter when the regeneration processing is being performed or both a CO concentration in exhaust gas flowing into the filter when the regeneration processing is being performed and a CO concentration in exhaust gas flowing out from the filter when the regeneration processing is being performed.