Systems and methods for dynamic control of filtration efficiency and fuel economy

An aftertreatment system configured to reduce constituents of an exhaust gas produced by an engine, comprising:

• a first filter;
• a second filter disposed downstream of the first filter;
• a bypass conduit fluidly coupling an exhaust gas flow path downstream of the first filter and upstream of the second filter to an exhaust gas flow path downstream of the second filter;
• a valve operatively coupled to the bypass conduit, the valve moveable between a closed position in which the exhaust gas flows through the second filter, and an open position in which at least a portion of the exhaust gas flows through the bypass conduit so as to bypass the second filter;
• and
• a controller operatively coupled to the valve, the controller configured to:
• determine whether the engine is operating in a high particulate matter operating condition or a low particulate matter operating condition;
• control the valve such that the valve is more closed during the high particulate matter operating condition of the engine than during the low particulate matter operating condition of the engine, such that a larger portion of the exhaust gas flows through the second filter during the high particulate matter operating condition of the engine than during the low particulate matter operating condition of the engine, the controlling of the valve causing the exhaust gas expelled into the environment from the aftertreatment system to have a particulate matter count which is lower than a predetermined threshold,
• wherein the valve is positioned at an inlet of the bypass conduit, the valve comprising:
• a first ring defining a plurality of first openings, and
• a second ring defining a plurality of second openings, the second ring abutting the first ring,
• wherein, in the closed position, the plurality of first openings are misaligned with the plurality of second openings such that the exhaust gas flows through the second filter, and wherein the second ring is configured to rotate relative to the first ring to move the valve into the open position in which the plurality of first openings are aligned with the plurality of second openings such that at least a portion of the exhaust gas flows through the plurality of first and second openings into the bypass conduit around the second filter.

An aftertreatment system for reducing constituents of an exhaust gas produced by an engine, comprising:

• a first filter;
• a second filter disposed downstream of the first filter;
• and
• a controller operatively coupled to the first and second filters, the controller configured to:
• determine a first filtration efficiency of the first filter during operation of the aftertreatment system;
• and
• in response to the first filtration efficiency being equal to or greater than a first filtration efficiency threshold, generate a fault code instructing a user to remove the second filter from the aftertreatment system.

An aftertreatment system configured to reduce constituents of an exhaust gas produced by an engine, comprising:

• a first filter;
• a second filter disposed downstream of the first filter;
• a bypass conduit fluidly coupling at least one of an exhaust gas flow path upstream of the first filter to an exhaust gas flow path between the first filter and the second filter or an exhaust gas flow path between the first filter and the second filter to an exhaust gas flow path downstream of the second filter;
• a valve operatively coupled to the bypass conduit, the valve moveable between a closed position in which the exhaust gas flows through the second filter, and an open position in which at least a portion of the exhaust gas flows through the bypass conduit so as to bypass the second filter;
• and
• a controller operatively coupled to the valve, the controller configured to:
• determine whether the engine is operating in a high particulate matter operating condition or a low particulate matter operating condition;
• control the valve such that the valve is more closed during the high particulate matter operating condition of the engine than during the low particulate matter operating condition of the engine, such that a larger portion of the exhaust gas flows through the second filter during the high particulate matter operating condition of the engine than during the low particulate matter operating condition of the engine, the controlling of the valve causing the exhaust gas expelled into the environment from the aftertreatment system to have a particulate matter count which is lower than a predetermined threshold,
• wherein the valve is positioned at an inlet of the bypass conduit, the valve comprising:
• a first ring defining a plurality of first openings, and
• a second ring defining a plurality of second openings, the second ring abutting the first ring,
• wherein, in the closed position, the plurality of first openings are misaligned with the plurality of second openings such that the exhaust gas flows through the second filter, and wherein the second ring is configured to rotate relative to the first ring to move the valve into the open position in which the plurality of first openings are aligned with the plurality of second openings such that at least a portion of the exhaust gas flows through the plurality of first and second openings into the bypass conduit around the second filter.