# US 11,306,641 B2 · Abnormality detection apparatus for electrically heated catalyst > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,641 B2 - Document ID: US11306641B2 - Status: Granted - Kind: B2 - Application number: 16/744,883 - Filed: 2020-01-16 - Published: 2020-07-23 - Granted: 2022-04-19 - Earliest claimed: 2019-01-17 - Assignees: Toyota Jidosha Kabushiki Kaisha - Applicants: Toyota Jidosha Kabushiki Kaisha - Inventors: Tsuyoshi Obuchi; Shigemasa Hirooka; Shingo Korenaga - Web page: https://patentgrep.com/patent/US11306641B2 ## CPC - F01N 9/00: Electrical control of exhaust gas treating apparatus (monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00) - F01N 3/2006: {Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating (by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235)} - F01N 3/2013: {using electric or magnetic heating means} - F01N 11/005: {the temperature or pressure being estimated, e.g. by means of a theoretical model} - F01N 2240/16: an electric heater, i.e. a resistance heater - F01N 2550/22: of electric heaters for exhaust systems or their power supply - F01N 2900/0602: Electrical exhaust heater signals - F01N 2900/1602: Temperature of exhaust gas apparatus - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) ## Abstract The controller adjusts a voltage applied to the electrically heated catalyst in such a way as to make the electrical power as the product of the applied voltage and the catalyst current equal to a target electrical power and to apply a voltage substantially equal to a specific upper limit voltage to the electrically heated catalyst when the electrical power that can be supplied to the electrically heated catalyst by applying a voltage equal to or lower than the specific upper limit voltage is lower than the target electrical power. The controller calculates an actually supplied electrical energy defined as the integrated value of the electrical power actually supplied to the electrically heated catalyst over a specific period. The controller determines that the electrically heated catalyst is abnormal if the actually supplied electrical energy is smaller than a specific electrical energy. ## Claims ### Claim 1 An abnormality detection apparatus for an electrically heated catalyst comprising; the electrically heated catalyst provided in an exhaust passage of an internal combustion engine, including an exhaust gas purification catalyst and a heater that generates heat when supplied with electrical power, an electrical resistance of the heater being larger when its temperature is low than when it is high during normal operation of the heater; and a controller including at least one processor, wherein the controller is configured to: adjust an applied voltage defined as a voltage applied to the electrically heated catalyst in such a way as to make the electrical power as the product of the applied voltage and a catalyst current defined as the electrical current flowing through the electrically heated catalyst per unit time equal to a target electrical power to be supplied to the electrically heated catalyst and adjust the applied voltage to a voltage substantially equal to a specific upper limit voltage, wherein the specific upper limit voltage is a design upper limit voltage determined by the structure and performance of a device used to supply electrical power to the electrically heated catalyst, when the electrical power, which is the electrical power that can be supplied to the electrically heated catalyst by applying a voltage equal to the specific upper limit voltage, is lower than the target electrical power; calculate an actually supplied electrical energy defined as the integrated value of the electrical power actually supplied to the electrically heated catalyst over a specific period from a time when the application of the applied voltage to the electrically heated catalyst is started to a time when a target electrical energy reaches a standard amount of electrical energy, the target electrical energy being defined as the integrated value of the target electrical power from the time when the application of the applied voltage to the electrically heated catalyst is started; and detect an abnormality of the electrically heated catalyst on the basis of the actually supplied electrical energy. ### Claim 2 (depends on 1) The abnormality detection apparatus for the electrically heated catalyst according to claim 1, wherein the standard amount of electrical energy is the total amount of electrical energy that is needed to raise the temperature of the electrically heated catalyst from its temperature at the time when the supply of electrical power is started to or above a specific temperature. ### Claim 3 (depends on 1) The abnormality detection apparatus for the electrically heated catalyst according to claim 1, wherein the controller determines that the electrically heated catalyst is abnormal, if the actually supplied electrical energy calculated by the controller is smaller than a specific electrical energy. ### Claim 4 (depends on 2) The abnormality detection apparatus for the electrically heated catalyst according to claim 2, wherein the controller determines that the electrically heated catalyst is abnormal, if the actually supplied electrical energy calculated by the controller is smaller than a specific electrical energy. ### Claim 5 (depends on 1) The abnormality detection apparatus for the electrically heated catalyst according to claim 1, wherein the controller is configured to calculate a ratio of the actually supplied electrical energy to the target electrical energy, and determine that the electrically heated catalyst is abnormal when the ratio is lower than a specific ratio. ### Claim 6 (depends on 2) The abnormality detection apparatus for the electrically heated catalyst according to claim 2, wherein the controller is configured to calculate a ratio of the actually supplied electrical energy to the target electrical energy, and determine that the electrically heated catalyst is abnormal when the ratio is lower than a specific ratio. ### Claim 7 (depends on 1) The abnormality detection apparatus for the electrically heated catalyst according to claim 1, wherein the controller is configured to calculate a change in the actually supplied electrical energy per unit time in the specific period, and determine that the electrically heated catalyst is abnormal when the change is smaller than a specific rate of change. ### Claim 8 (depends on 2) The abnormality detection apparatus for the electrically heated catalyst according to claim 2, wherein the controller is configured to calculate a change in the actually supplied electrical energy per unit time in the specific period, and determine that the electrically heated catalyst is abnormal when the change is smaller than a specific rate of change.