# US 2023/0271602 A1 · Controller for hybrid electric vehicle and method for controlling hybrid electric vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0271602 A1 - Document ID: US20230271602A1 - Status: Published application - Kind: A1 - Application number: 18/159,763 - Filed: 2023-01-26 - Published: 2023-08-31 - Earliest claimed: 2022-02-28 - Assignees: Toyota Jidosha Kabushiki Kaisha - Applicants: Toyota Jidosha Kabushiki Kaisha - Inventors: Tomohiro NAKANO; Shinichi ODA; Masanao IDOGAWA; Koji ICHIKAWA; Atsushi FUKUDA - Web page: https://patentgrep.com/patent/US20230271602A1 ## CPC - B60K 6/48: Parallel type - B60W 20/40: Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers {(power-up or power-down of the driveline B60W30/192)} - B60K 6/40: characterised by the assembly or relative disposition of components - B60W 10/02: including control of driveline clutches - B60W 10/06: including control of combustion engines - B60W 10/08: including control of electric propulsion units, e.g. motors or generators - B60W 20/00: Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} - B60W 20/15: Control strategies specially adapted for achieving a particular effect - B60W 20/16: for reducing engine exhaust emissions - B60K 2006/4825: {Electric machine connected or connectable to gearbox input shaft} - B60W 2510/0208: Clutch engagement state, e.g. engaged or disengaged - B60W 2510/0638: Engine speed - B60W 2510/0676: Engine temperature - B60W 2510/081: Speed - B60W 2540/16: Ratio selector position - B60W 2710/021: Clutch engagement state - B60W 2710/0644: Engine speed - B60Y 2200/92: Hybrid vehicles - Y02T 10/62: Hybrid vehicles - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A controller controls a hybrid electric vehicle. The hybrid electric vehicle includes an engine, a motor arranged in a power transmission path between the engine and a drive wheel, and a clutch arranged in the power transmission path between the engine and the motor. The controller idles the engine in accordance with a target engine rotation speed and operates the motor in accordance with a target motor rotation speed when the clutch is in a disengagement state. When the clutch is in the disengagement state and the engine is idling, the target motor rotation speed is less than the target engine rotation speed. ## Claims ### Claim 1 A controller for a hybrid electric vehicle, wherein the hybrid electric vehicle includes an engine, a motor arranged in a power transmission path between the engine and a drive wheel, and a clutch arranged in the power transmission path between the engine and the motor, the controller comprising: processing circuitry, wherein the processing circuitry is configured to idle the engine in accordance with a target engine rotation speed and operate the motor in accordance with a target motor rotation speed when the clutch is in a disengagement state, and when the clutch is in the disengagement state and the engine is idling, the target motor rotation speed is less than the target engine rotation speed. ### Claim 2 (depends on 1) The controller according to claim 1, wherein when the clutch is to be shifted from the disengagement state to an engagement state, the processing circuitry is configured to execute: a process that matches the target engine rotation speed that is greater than the target motor rotation speed with the target motor rotation speed; a process that waits for an engine rotation speed to match the target engine rotation speed; and a process that controls and shifts the clutch to the engagement state. ### Claim 3 (depends on 1) The controller according to claim 1, wherein when the clutch is in the disengagement state and the engine is idling, the processing circuitry is configured to set the target motor rotation speed based on a gearshift position irrespective of an operation state of the engine. ### Claim 4 (depends on 1) The controller according to claim 1, wherein when the clutch is in the disengagement state and the engine is performing a warm-up operation, the processing circuitry is configured to set the target engine rotation speed based on a warm-up state of the engine irrespective of a gearshift position. ### Claim 5 (depends on 4) The controller according to claim 4, wherein the target engine rotation speed that is set based on the warm-up state of the engine is higher when an engine coolant temperature is lower. ### Claim 6 (depends on 5) The controller according to claim 5, wherein when the clutch is in the disengagement state and the engine is performing the warm-up operation, the processing circuitry is configured to set the target motor rotation speed based on the gearshift position and the warm-up state of the engine, the target motor rotation speed that is set based on the gearshift position and the warm-up state of the engine is higher when the engine coolant temperature is lower, if the clutch is to be shifted to an engagement state when the clutch is in the disengagement state and the engine is performing the warm-up operation, the processing circuitry is configured to execute: a process that matches the target engine rotation speed that is greater than the target motor rotation speed with the target motor rotation speed; a process that waits for an engine rotation speed to match the target engine rotation speed; and a process that controls and shifts the clutch to the engagement state. ### Claim 7 (depends on 1) The controller according to claim 1, wherein the processing circuitry is configured to execute a high temperature restarting process if an intake air temperature is higher than or equal to an intake air temperature threshold value and an engine coolant temperature is higher than or equal to a coolant temperature threshold value when the engine is started, the high temperature restarting process includes setting the target engine rotation speed, and the target engine rotation speed that is set in the high temperature restarting process is higher when the engine coolant temperature is higher. ### Claim 8 (depends on 7) The controller according to claim 7, wherein when the clutch is in the disengagement state and the high temperature restarting process is executed, the processing circuitry is configured to set the target motor rotation speed based on a gearshift position and the engine coolant temperature, the target motor rotation speed that is set in the high temperature restarting process is higher when the engine coolant temperature is higher, if the clutch is to be shifted to an engagement state when the clutch is in the disengagement state and the high temperature restarting process is being executed, the processing circuitry is configured to execute: a process that matches the target engine rotation speed that is greater than the target motor rotation speed with the target motor rotation speed; a process that waits for an engine rotation speed to match the target engine rotation speed; and a process that controls and shifts the clutch to the engagement state. ### Claim 9 A method for controlling a hybrid electric vehicle, wherein the hybrid electric vehicle includes an engine, a motor arranged in a power transmission path between the engine and a drive wheel, and a clutch arranged in the power transmission path between the engine and the motor, the method comprising: idling the engine in accordance with a target engine rotation speed and operating the motor in accordance with a target motor rotation speed when the clutch is in a disengagement state, wherein when the clutch is in the disengagement state and the engine is idling, the target motor rotation speed is less than the target engine rotation speed.