POWER INVERTER

• US 20090040724A1
• Filed: 08/08/2008
• Published: 02/12/2009
• Est. Priority Date: 08/09/2007
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: NISHIKIMI, Fusanori, Nakatsu, Kinya
• Granted Patent: US 8,699,254 B2
• Time in Patent Office: Days
• US Class Current: 361/699
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/19107 off-chip wires
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H02M 7/219 in a bridge configuration
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• CPC Class Codes: H05K 7/20927 Liquid coolant without phase change

Abstract

In a power inverter, a coolant passage is fixed to a chassis to cool the chassis; the chassis is divided into a first region and a second region by providing the coolant passage in the chassis; a power module is provided in the first region as fixed to the coolant passage; a capacitor module is provided in the second region; and the DC terminal of the capacitor module is directly connected to the DC terminal of the power module.

Claims

1. A power inverter, comprising:

a power module that comprises a plurality of switching devices for an upper arm and a lower arm that make up an inverter circuit, a metal board that releases heat generated by the plurality of the switching devices, a DC terminal and an AC terminal;

a smoothing capacitor module that comprise a DC terminal;

a gate drive circuit that drives the power module;

a coolant passage through which coolant flows; and

a chassis that houses the power module, the capacitor module, the gate drive circuit, and the coolant passage, wherein;

the coolant passage is fixed to the chassis to cool the chassis;

the chassis is divided into a first region and a second region by providing the coolant passage in the chassis;

the power module is provided in the first region as fixed to the coolant passage;

the capacitor module is provided in the second region; and

the DC terminal of the capacitor module is directly connected to the DC terminal of the power module.

2. A power inverter according to claim 1, wherein:

the chassis is formed with an upper opening opened at an upper end and a lower opening at a lower end of the chassis;

the first region exists between the coolant passage and the upper opening;

the second region exists between the coolant passage and the lower opening;

the lower opening is covered with a lower cover and the upper opening is covered with an upper cover; and

a heat conduction passage is formed between the lower cover and the capacitor module.

6. A power inverter according to claim 1, wherein:

the chassis is formed with a heat conduction member, and

the capacitor module and the gate drive circuit are cooled by coolant flowing through the coolant passage via the chassis.

7. A power inverter according to claim 1, wherein:

the DC terminal of the capacitor module, that is electrically connected with the DC terminal of the power module, comprises a positive busbar and a negative busbar, with the positive busbar and the negative busbar laminated to form a laminated busbar;

each of the positive busbar and the negative busbar that makeup the laminated busbar, comprises a connection section;

the connection section of the positive busbar and the connection section of the negative busbar are bent in opposite directions to each other such that internal surfaces of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces at the connection sections; and

the DC terminal of the capacitor module is electrically connected to the DC terminal of the power module via the connecting surface of the positive busbar and the connecting surface of the negative busbar.

8. A power inverter according to claim 1, wherein:

the capacitor module comprises;

a capacitor case;

a laminated busbar that comprises a positive busbar and a negative busbar sandwiching an insulation material to form a laminated structure, and a planar section that is an external surface of the laminated positive busbar and negative busbar;

a plurality of capacitor cells that are arranged in parallel on the planar section of the laminated busbar and a positive terminal and a negative terminal of the capacitor cells are connected to the positive busbar and the negative busbar respectively; and

the planar section of the laminated busbar and the plurality of the capacitor cells housed in the capacitor case;

wherein;

the laminated busbar extends and protrudes from the capacitor case, an end of the positive busbar and an end of the negative busbar that make up the protruded laminated busbar are bent in opposite directions to each other such that internal surfaces at an the end of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces; and

the DC terminal of the capacitor module is electrically connected to the DC terminal of the power module via the connecting surface of the positive busbar and the connecting surface of the negative busbar.

9. A power inverter according to claim 8, wherein:

each of the capacitor cells comprises a wound film conductor and is arranged such that an outer circumference surface of each of the capacitor cells faces the planar section of the laminated busbar; and

each of end faces of the capacitor cells formed with the wound film conductor is electrically connected to the laminated busbar.

10. A power inverter according to claim 1, wherein:

the DC terminal of the power module comprises a laminated busbar made up of a positive busbar and a negative busbar;

each of the positive busbar and the negative busbar that make up the laminated busbar, comprises a connection section;

the connection section of the positive busbar and the connection section of the negative busbar are bent in opposite directions to each other such that internal surfaces of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces at the connection sections; and

the DC terminal of the power module is electrically connected to the DC terminal of the capacitor module via the connecting surface of the positive busbar and the connecting surface of the negative busbar.

11. A power inverter according to claim 7, wherein:

the DC terminal of the power module comprises a laminated busbar made up of a positive busbar and a negative busbar;

each of the positive busbar and the negative busbar that make up the laminated busbar, comprises a connection section;

the connection section of the positive busbar and the connection section of the negative busbar are bent in opposite directions to each other such that internal surfaces of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces at the connection sections; and

the connecting surface of the positive busbar and the connecting surface of the negative busbar of the DC terminal of the power module are directly connected to the connecting surface of the positive busbar and the connecting surface of the negative busbar of the DC terminal of the capacitor module, respectively.

12. A power inverter according to claim 1, wherein:

the power module comprises a AC terminal that is shaped in a plate and protrudes from the power module;

the AC terminal is provided with a hole into which a protrusion or a pin provided in a case of the power module is inserted; and

the AC terminal is sustained by the protrusion or the pin and the hole against outer vibration to the AC terminal fixed on the case of the power module.

3. A power inverter, comprising:

a chassis that comprises an upper opening at an upper end and a lower opening at a lower end of the chassis;

an upper cover and a lower cover that cover the upper opening and the lower opening respectively;

a power module that is housed in the chassis and comprises a plurality of switching devices for an upper arm and a lower arm that make up an inverter circuit, a metal board that releases heat generated by the plurality of the switching devices, and a DC terminal and an AC terminal;

a smoothing capacitor module that comprises a DC terminal and smoothes a DC voltage applied to the DC terminal of the smoothing capacitor module, with the DC terminal of the smoothing capacitor module electrically connected with the DC terminal of the power module;

a gate drive circuit, housed in the chassis, that drives the power module; and

a coolant passage, on which the power module is mounted, that is provided substantially parallel to the upper cover or the lower cover in the chassis;

wherein;

the chassis is provided with a first region between the upper cover and the coolant passage and a second region between the lower cover and the coolant passage, by providing the coolant passage inside the chassis;

the power module is provided in the first region;

a semiconductor module for auxiliaries and the capacitor module are provided in the second region; and

a space that links the first region and the second region is created between a side of the coolant passage and the chassis, and the DC terminal of the capacitor module and the DC terminal of the power module are electrically connected with each other through the space.

4. A power inverter according to claim 3, wherein:

the chassis is a substantially rectangular on an upper side;

a water passage is formed in the coolant passage from a short side of the chassis, extends along a long side of the chassis, turns around, and returns along another long side of the chassis again to the short side;

the space that links the first region and the second region is formed between the water passage that extends along one of the long sides and the one of the long sides of the chassis;

the power module is fixed on the water passage that is bent and extends along the long sides of the rectangle; and

the DC terminal of the power module is placed in the space and electrically connected with the DC terminal of the capacitor module through the space.

5. A power inverter according to claim 4, wherein:

the DC terminal of the capacitor module and the DC terminal of the power module are electrically and directly connected with each other through the space.

16. A power inverter according to claim 3, wherein:

the chassis is formed with a heat conduction member, and

the capacitor module and the gate drive circuit are cooled by coolant flowing through the coolant passage via the chassis.

17. A power inverter according to 3, wherein:

the DC terminal of the capacitor module, that is electrically connected with the DC terminal of the power module, comprises a positive busbar and a negative busbar, with the positive busbar and the negative busbar laminated to form a laminated busbar;

each of the positive busbar and the negative busbar that make up the laminated busbar, comprises a connection section;

the connection section of the positive busbar and the connection section of the negative busbar are bent in opposite directions to each other such that internal surfaces of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces at the connection sections; and

the DC terminal of the capacitor module is electrically connected to the DC terminal of the power module via the connecting surface of the positive busbar and the connecting surface of the negative busbar.

18. A power inverter according to claim 3, wherein:

the capacitor module comprises;

a capacitor case;

a laminated busbar that comprises a positive busbar and a negative busbar sandwiching an insulation material to form a laminated structure, and a planar section that is an external surface of the laminated positive busbar and negative busbar;

a plurality of capacitor cells that are arranged in parallel on the planar section of the laminated busbar and a positive terminal and a negative terminal of the capacitor cells are connected to the positive busbar and the negative busbar respectively; and

the planar section of the laminated busbar and the plurality of the capacitor cells housed in the capacitor case;

wherein;

the laminated busbar extends and protrudes from the capacitor case, an end of the positive busbar and an end of the negative busbar that make up the protruded laminated busbar are bent in opposite directions to each other such that internal surfaces at an the end of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces; and

the DC terminal of the capacitor module is electrically connected to the DC terminal of the power module via the connecting surface of the positive busbar and the connecting surface of the negative busbar.

19. A power inverter according to claim 3, wherein:

the DC terminal of the power module comprises a laminated busbar made up of a positive busbar and a negative busbar;

each of the positive busbar and the negative busbar that make up the laminated busbar, comprises a connection section;

the connection section of the positive busbar and the connection section of the negative busbar are bent in opposite directions to each other such that internal surfaces of the positive busbar and the negative busbar having been laminated are opened to provide connecting surfaces at the connection sections; and

the DC terminal of the power module is electrically connected to the DC terminal of the capacitor module via the connecting surface of the positive busbar and the connecting surface of the negative busbar.

20. A power inverter according to claim 3, wherein:

the power module comprises a AC terminal that is shaped in a plate and protrudes from the power module;

the AC terminal is provided with a hole into which a protrusion or a pin provided in a case of the power module is inserted; and

the AC terminal is sustained by the protrusion or the pin and the hole against outer vibration to the AC terminal fixed on the case of the power module.

13. A power inverter, comprising:

a coolant passage chassis that comprises an upper cover and a lower cover;

a power module, provided in the coolant passage chassis, that comprises a plurality of switching devices used for an inverter circuit, a metal board, shaped in a plate, that releases heat generated by the plurality of the switching devices, a DC terminal, and an AC terminal;

a smoothing capacitor module, provided in coolant passage chassis, that comprises a DC terminal which is electrically connected with a DC terminal of the power module;

a gate drive circuit, provided in the coolant passage chassis, that drives the power module; and

a cooling unit that comprises a coolant passage provided in the coolant passage chassis, wherein;

by providing the coolant passage in the cooling unit chassis, a first region is created on one side of the coolant passage and a second region is created on an other side of the coolant passage;

the metal board of the power module is fixed on the cooling unit in the first region;

the capacitor module is provided in the second region;

a space that links the first region and the second region is created on a side of the coolant passage of the cooling unit; and

the DC terminal of the capacitor module and the DC terminal of the power module are electrically connected with each other through the space.

14. A power inverter according to claim 13, wherein:

the DC terminal of the capacitor module comprises a laminated busbar that is made up of a positive busbar and a negative busbar, and that protrudes from the capacitor module;

a capacitor cell is provided on one side of the laminated busbar in the capacitor module; and

the laminated busbar outside the capacitor module extends into the first region through the space that links the first region and the second region, and is connected to the DC terminal of the power module.

15. A power inverter according to claim 14, wherein:

at an end of the DC terminal of the capacitor module, the positive busbar and the negative busbar which make up the laminated busbar, are bent in opposite directions to each other, and each of surfaces of the positive busbar and the negative busbar in the laminated busbar forms a connecting surface;

at an end of the DC terminal of the power module, the positive busbar and the negative busbar which make up the laminated busbar, are bent in opposite directions to each other, and each of surfaces of the positive busbar and the negative busbar in the laminated busbar forms a connecting surface; and

the connecting surfaces of the DC terminal of the capacitor module and the connecting surfaces of the DC terminal of the power module are connected with each other.