COOLING STRUCTURE FOR INVERTER DEVICE

• US 20150070841A1
• Filed: 04/03/2013
• Published: 03/12/2015
• Est. Priority Date: 04/10/2012
• Status: Active Grant

• Current Assignee: NTN Corporation
• Original Assignee: NTN Corporation
• Inventors: Suzuki, Minoru, Yamamoto, Tetsuya, Okada, Koichi
• Granted Patent: US 9,402,336 B2
• Time in Patent Office: Days
• US Class Current: 361/689
• CPC Class Codes: B60K 11/02 with liquid cooling
• CPC Class Codes: B60K 11/06 with air cooling
• CPC Class Codes: B60K 2001/003 with means for cooling the electrical propulsion units
• CPC Class Codes: B60K 2001/0416 Arrangement in the rear part of the vehicle
• CPC Class Codes: B60K 2007/0038 the motor moving together with the wheel axle
• CPC Class Codes: B60K 2007/0092 the motor axle being coaxial to the wheel axle
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 15/2036 Electric differentials, e.g. for supporting steering vehicles
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/44 Wheel Hub motors, i.e. integrated in the wheel hub
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/525 Temperature of converter or components thereof
• CPC Class Codes: B60L 2250/26 by pedal actuation
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: H02M 7/537 : using semiconductor devices only, e.g. single switched pulse inverters
• CPC Class Codes: H05K 7/2089 : for power electronics, e.g. for inverters for controlling motor
• CPC Class Codes: H05K 7/209 : Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20909 takes precedence
• CPC Class Codes: H05K 7/20927 : Liquid coolant without phase change
• 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 10/72 : Electric energy management in electromobility

Abstract

A cooling structure for an inverter (31) controls a motor (6) to drive an automobile. This inverter device (22) includes a power circuit section (28) having an inverter (31) to convert a DC power of a battery (19) to an AC power for the motor (6), and a casing (39) enclosing the power circuit section (28). A fin (41) is provided in an outer surface of the casing (39), a coolant path (42) for the flow of a cooling medium is provided within the casing (39) or in the outer surface thereof, and a pump (43) circulating the cooling medium in the coolant path (42) is disposed in the casing (39). With this structure, the flow resistance for cooling the inverter (31) is reduced to allow the pump (43) to be downsized and a proper cooling can be accomplished to the amount of heat by the inverter (31).

Claims

1. A cooling structure for an inverter device to control an automobile driving motor, which inverter device comprises:

a power circuit section including an inverter configured to convert a direct current power of a battery to an alternating current power for driving the motor, and an inverter casing to enclose the power circuit section; and

a fin provided in an outer surface area of the inverter casing, a coolant flow path provided within the inverter casing or in the outer surface area for the flow of a cooling medium therethrough, and a pump disposed in the inverter casing to circulate the cooling medium within the coolant flow path.

2. The cooling structure for the inverter device as claimed in claim 1, further comprising an inverter temperature detecting unit to detect the temperature of the inverter and a pump control unit to perform such a control that, in the event that the temperature detected by the inverter temperature detecting unit exceeds a preset value, the pump is driven to circulate the cooling medium.

3. The cooling structure for the inverter device as claimed in claim 1, further comprising a pump control unit to perform such a control that, in the event that an automobile traveling velocity is not higher than a predetermined value, the pump is driven to circulate the cooling medium.

4. The cooling structure for the inverter device as claimed in claim 1, further comprising a cooling water tank to reserve a cooling water provided in the vicinity of a portion within the inverter casing where the fin is provided.

5. The cooling structure for the inverter device as claimed in claim 4, further comprising a stirrer to stir the cooling water within the cooling water tank, the stirrer being provided in the inverter casing.

6. The cooling structure for the inverter device as claimed in claim 1, in an automobile body having an under guard disposed therein, the fin is disposed between the automobile body and the under guard while being exposed.

7. The cooling structure for the inverter device as claimed in claim 6, in which the under guard is provided with an air intake hole defined between the automobile body and the under guard to take air thereinto.

8. The cooling structure for the inverter as claimed in claim 7, further comprising a filter to remove foreign matter, the filter being disposed in the air intake hole in the under guard.