Electric vehicle

• US 9,242,560 B2
• Filed: 09/25/2012
• Issued: 01/26/2016
• Est. Priority Date: 09/26/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Hashimoto, Hironobu
• Primary Examiner(s): Follman, Brodie
• Assistant Examiner(s): Cassidy, Brian
• Application Number:
  US13/626,530
• Publication Number:
  US 20130076126A1
• Time in Patent Office: 1,218 Days
• Field of Search: 307/9.1, 180/65.245
• US Class Current: 1/1
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 15/2036 Electric differentials, e.g. for supporting steering vehicles
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/42 with use of more than one motor
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/425 Temperature
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/525 Temperature of converter or components thereof
• CPC Class Codes: B60L 2250/12 by confirmation, e.g. of the input
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/30 for monitoring or controlling fuel cells
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

An electric vehicle includes: an electric motor; an inverter that supplies electric power to the electric motor; and a cooling system that cools at least one of the electric motor and the inverter, the cooling system having: a main coolant passage configured to circulate a coolant through a radiator and at least one of the electric motor and the inverter; a bypass coolant passage, connected to the main coolant passage, that bypasses at least one of the electric motor and the inverter; and a controller configured to switch from the main coolant passage to the bypass coolant passage when a main switch of the vehicle provided at a driver'"'"'s seat is turned off while the electric vehicle is travelling, and to switch from the bypass coolant passage to the main coolant passage when the main switch is then turned on.

Claims

1. An electric vehicle comprising:

an electric motor for driving a wheel;

an inverter that supplies electric power to the electric motor; and

a cooling system that cools at least one of the electric motor and the inverter, the cooling system including;

a main coolant passage configured to circulate a coolant through a radiator and at least one of the electric motor and the inverter;

a bypass coolant passage that is connected to the main coolant passage and that bypasses at least one of the electric motor and the inverter; and

a controller configured to switch from the main coolant passage to the bypass coolant passage when an ignition switch of the vehicle, that is provided at a driver'"'"'s seat, is switched from an on-state to an off-state while the electric vehicle is travelling, and to switch from the bypass coolant passage to the main coolant passage when the ignition switch is switched back to the on-state.

2. The electric vehicle according to claim 1, wherein

the controller is configured so that while the bypass coolant passage is selected, the controller keeps, at a first rotation speed, rotation speed of a radiator fan that cools the coolant when vehicle speed is less than or equal to a predetermined threshold vehicle speed value, and keeps the rotation speed of the radiator fan at a second rotation speed that is lower than the first rotation speed when the vehicle speed is higher than the threshold vehicle speed value.

3. The electric vehicle according to claim 1, further comprising

a power distribution mechanism that includes a planetary carrier connected to an engine, a sun gear and a ring gear, wherein:

one of the sun gear and the ring gear is connected to a first electric motor;

the other of the sun gear and the ring gear is connected to a second electric motor, and is connected to an axle shaft; and

the power distribution mechanism is configured so that rotation direction of the first electric motor when the engine is rotating and the rotation direction of the first electric motor when the engine is in a stopped state are opposite to each other.

4. The electric vehicle according to claim 1, further comprising

a pump for circulating the coolant, wherein

the controller is configured to continue driving the pump even when the ignition switch is switched from the on-state to the off-state while the electric vehicle is travelling.

5. The electric vehicle according to claim 1, wherein

the bypass coolant passage includes a motor bypass coolant passage that bypasses the motor, and

the controller is configured not to perform switching from the main coolant passage to the motor bypass coolant passage when a temperature of the motor is higher than a predetermined temperature range.

6. The electric vehicle according to claim 1, wherein

the bypass coolant passage includes an inverter bypass coolant passage that bypasses the inverter, and

the controller is configured not to perform switching from the main coolant passage to the inverter bypass coolant passage when a temperature of the inverter is higher than a predetermined temperature range.