Source: https://patents.google.com/patent/US8072760B2/en
Timestamp: 2018-12-18 16:14:22
Document Index: 690598674

Matched Legal Cases: ['Application No. 2006', 'art 904', 'art 904', 'art 904', 'art 916', 'art 916', 'art 916']

US8072760B2 - Power inverter - Google Patents
US8072760B2
US8072760B2 US12759824 US75982410A US8072760B2 US 8072760 B2 US8072760 B2 US 8072760B2 US 12759824 US12759824 US 12759824 US 75982410 A US75982410 A US 75982410A US 8072760 B2 US8072760 B2 US 8072760B2
US12759824
US20110032676A1 (en )
This application is a Continuation of U.S. application Ser. No. 11/581,336, filed Oct. 17, 2006, now U.S. Pat. No. 7,710,721 which claims priority from Japanese Patent Application No. 2006-122885, filed on Apr. 27, 2006, the contents of which are incorporated herein by reference.
The structure of the power converter 200 as shown in FIGS. 2-7 will be explained in detail as follows. (housing 210)
The cover 290 is made of a material similar to that of the housing 210, and is fixed to the housing 210 (refer to FIG. 5) by screws SC7 screwed into the upper end surfaces of the housing 210 through screw holes arranged circumferentially at the substantially constant interval on its periphery.
As described above, the coolant water path is formed at the bottom of the power converter 200. FIG. 12 is a structural view seen upward from the bottom of the housing 210 to show a water path holder member 902 as a part of the water path forming body 220. The water path holder member 902 has an outer peripheral part 904 on which a bottom plate as another part of the water path forming body 220 is mounted, and the outer peripheral part 904 includes holes SC9 for screw fixing. Some of them have denoting numbers, and the other of them have no denoting number. A seal groove 906 is arranged at an inner side of the outer peripheral part 904 to prevent the water leakage, and the water path holder member 902 at the inner side of the seal groove 906 has outer regions 912 at its both sides, as well as the first and second water paths 922 and 924 and central area 908 referred to as the coolant water path 216 in the previous drawing. An O-ring or rubber seal is fitted into the seal groove and the screw holes) are tightened by the screws to obtain the seal function. The coolant water is supplied to an inlet part 916 of the water path 922 (previously referred to as 216), the coolant water flows through the first water path 922 in a direction of arrow, a flow direction of the coolant water is changed in U-shape by a fold back path 924 to flow through the second water path in the direction of arrow, and the flow is discharged from a discharge port 918 of the water path 924. The first and second water paths 922 and 924 have openings 218 and 219 as holes. By attaching the bottom plate 934 in FIG. 13 as described below, the water paths 922 and 924 are formed and the openings 218 and 219 open to the water paths.
A cross section of the water path 922 along II-II section in FIG. 12 is shown in FIG. 14. Incidentally, the water path 926 has the substantially same shape. in FIGS. 12, 13 and 14, the water path holder member 902 includes water paths 922 and 924 parallel to each other. The coolant water is introduced from the inlet pipe 212 (not shown in FIG. 12) into an inlet part 916. The inlet part 916 of the water path includes a metallic roof 882 monolithically formed with the housing 210, and metallic side walls 988 and 990 monolithically formed with the housing 210 are arranged at both sides of the water path. A width of the water path increases gradually and a depth thereof decreases gradually at a downstream side of the inlet pipe as shown in FIG. 12. Therefore, the flow of the coolant water is made smooth to restrain bubbles from being generated and to decrease a flow resistance. The water is introduced from the inlet part into the water path with the opening. The water path with the opening has a protrusion 935 at its bottom as shown in FIG. 13 so that the bottom of the water path is elevated and the depth of the water path is slightly deeper than a height of the heat radiating fin. The height of the heat radiating fin is 6-8 mm, and the depth of the water path is not more than 10 mm, preferably not more than 9 mm.
FIG. 15 is an enlarged partial view along section of FIG. 14. The bottom plate 934 is arranged at the bottom of the water path forming body 220 to form the water path 922. Both sides of the water path are defined by side plates 988 and 990 monolithically formed with the housing 210. A sealing between the side plates 988 and 990 and the water path forming body 220 is performed by a sealing member 986 such as O-ring or gasket whose width is greater than the O-ring. The opening 218 above the water path 922 is closed by the heat radiating surface of the metallic base plate 944 of the power module 502 as described above. The sealing member 986 such as O-ring or gasket whose width is greater than the O-RING is used for the sealing. The plurality of the semiconductor chips are fixed to the other surface of the metallic base plate 944 and sealed by the resin case 946.
In the above description, as shown in FIG. 14, the water path is made deep at the inlet, outlet and fold back portions, and the region in which the heat radiating fin is inserted is made shallow in comparison with the above portions. The depth of the water path at the region in which the heat radiating fin is inserted is slightly greater than the height of the heat radiating fin. In this embodiment, the height of the heat radiating fin is 6-8 mm. the depth of the water path is not more than 10 mm, preferably not more than 9 mm. The above structure and functional effect is also obtainable in the power module 504 and the water path forming body including the water path.
The metallic base plate 944 is an alloy including a main component of copper and impurities. It preferably has a hardness not less than HV50 after the heat radiating fin is fixed by the brazing and a thermal conductivity not less than 200 W/mK. A thickness of the base plate is 2-4 mm. The flatness at a part thereof overlapping the insulating substrate or surrounded by the fixing screw holes 978 is preferably not more than 0.2 mm or is not more than 0.1 mm as optimum value. Further, the flatness at the other part thereof overlapping the six insulating substrates or the semiconductor chips forming the inverter is preferably not more than 0.4 mm or is not more than 0.3 mm as optimum value. When the copper includes the impurity harder than the copper, the hardness thereof increases in accordance with an increase in rate thereof. On the other hand, since the impurities are of lower thermal conductivity than copper, the thermal conductivity as the whole decreases. Therefore, it is preferable for the rate of the impurities to be adjusted to maintain the hardness and the thermal conductivity. Further, it is preferable for the base plate to be plated with nickel of thickness of about 3-9 μm. As shown in FIG. 18, the heat radiating fin 506 is attached to one of surfaces thereof by brazing and the insulating substrate of the semiconductor chips is attached to the other one of surfaces thereof by soldering. There is a probability of that the surface of cupper includes scratch, whereby the plating of suitable thickness enables the surface roughness to be kept suitable. In this embodiment, it is preferable for the region where at least the insulating substrate is mounted and the O-ring is arranged to have the surface roughness for satisfying Ra=3.2.
FIGS. 20(A)-(C) are outer views of the power module 502 or 504. FIG. 20(A) is a plan view of the power module 502 or 504, FIG. 20(B) is a side view thereof, and FIG. 20(C) is a front view thereof. As described above, the power module shown in FIGS. 16 and 17 does not include the resin case shown in FIG. 20. Incidentally, the heat radiating fin 506 in FIGS. 16 and 17 has the wave shape other than the pin shape. In FIG. 20(A) as the plan view, the terminals OTiu, OTiv and OTiw for the alternating current to be connected to the rotary motor are arranged at an end. Thee sets of terminals IT1N and IT1P for the direct current to be connected to the direct current electric source are arranged at another end as opposite side. These terminals are arranged as shown in FIG. 9 to be connected to the terminals of the capacitor. incidentally, the terminal IT1N is connected to a negative side of the direct current electric source, and the IT1P is connected to a positive side of the direct current electric source. The terminals for the positive side are electrically connected to each other in parallel, and the terminals for the negative side are electrically connected to each other in parallel, in the three sets of the terminals IT1N and IT1P for the direct current in FIG. 20.
FIG. 22 is a view of a circuit of the power converter 200 of the embodiment, and the power converter 200 includes the first power module 502 as the inverter, the second power module 504 as the inverter, the capacitor module 300, the drive circuit 92 mounted on the first drive circuit substrate 602 of the inverter, the drive circuit 94 mounted on the second drive circuit substrate 604 of the inverter, the control circuit 93 mounted on the rotary motor control circuit substrate 700, a connector 73 mounted on the connector substrate 72, a drive circuit 91 for driving the electric discharge circuit (not shown) of the capacitor module 300, and electric current sensors 95 and 96.
The capacitor module 300 is arranged to position the electric terminals at the lower side of the central region (defined by two legs of π) of the second base 12 in the vicinity of the direct current side terminals of the first power module 502 and the second power module 504. The capacitor module 300 is constituted by four electrolytic capacitors of elliptical cross sectional shape in the height direction of the housing. The four electrolytic capacitors are arranged to juxtapose two of them in each of the longitudinal direction and the transverse direction while those longitudinal directions are parallel to the longitudinal direction of the housing, and are contained in the capacitor case 51 through the holder band 52. The capacitor case 51 is a thermally conductive container whose upper part is opened, and the lower ends of the two legs of 7 contact a flange of the upper part of the case. Therefore, the capacitor modules 300 and the coolant path (water paths 922 and 926) are thermally connected to each other with high thermal conductivity to cool sufficiently the capacitor module 300.
1. A power convertor comprising:
a cooling path forming body forming a path for refrigerant, and
a power module fixed to the cooling path forming body and including a plurality of power semiconductor chips for converting a direct electric current to an alternating electric current,
wherein the power module further includes a base plate, a heat radiating element fixed to a surface of the base plate through a brazing material, and an insulating substrate, a surface of which is fixed to another surface of the base plate through a solder layer, and
the base plate is made of copper alloy including a material whose hardness is higher than a hardness of copper, has a hardness not less than HV50, and has a thermal conductivity not less than 200 W/mK,
wherein the cooling path forming body includes an opening communicating with the path, the heat radiating element projects from the opening into the path, the power module is fixed to the cooling path forming body in such a manner that the opening is closed by the base plate,
wherein each of the power semiconductor chips is fixed to another surface of the insulating substrate through a second solder layer, and
a melting point of the second solder layer is lower than a brazing temperature of the brazing material through which the heat radiating element is fixed to the surface of the base plate, and higher than a melting point of the solder layer.
2. The power convertor according to claim 1, wherein a part of the base plate facing to the insulating substrate has a flatness not more than 0.2 mm.
3. The power convertor according to claim 2, wherein another part of the base plate facing to the power semiconductor chip has a flatness not more than 0.4 mm.
4. The power convertor according to claim 1, wherein the heat radiating element includes a heat radiating fin of wave shape.
5. The power convertor according to claim 1, wherein the heat radiating element includes a heat radiating fin of pin shape.
6. The power convertor according to claim 1, wherein the heat radiating element includes first, second and third heat radiating parts,
the base plate has a first base area onto which the first radiating part is fixed, a second base area onto which the second radiating part is fixed, and a third base area onto which the third radiating part is fixed,
the insulating substrate includes a first insulating area on which a switching element for outputting U-phase component of the alternating current, a second insulating area on which a switching element for outputting V-phase component of the alternating current, and a third insulating area on which a switching element for outputting W-phase component of the alternating current,
the first insulating area faces to the first base area through the solder layer, the base plate and the brazing material,
the second insulating area faces to the second base area through the solder layer, the base plate and the brazing material, and
the third insulating area faces to the third base area through the solder layer, the base plate and the brazing material.
7. The power convertor according to claim 1, wherein a thickness of the base plate is 2-4 mm.
8. The power convertor according to claim 1, wherein the base plate is plated with nickel of thickness of about 3-9 μm.
US12759824 2006-04-27 2010-04-14 Power inverter Active US8072760B2 (en)
US11581336 US7710721B2 (en) 2006-04-27 2006-10-17 Power inverter
US12759824 US8072760B2 (en) 2006-04-27 2010-04-14 Power inverter
US11581336 Continuation US7710721B2 (en) 2006-04-27 2006-10-17 Power inverter
US20110032676A1 true US20110032676A1 (en) 2011-02-10
US8072760B2 true US8072760B2 (en) 2011-12-06
US11581336 Active US7710721B2 (en) 2006-04-27 2006-10-17 Power inverter
US12759824 Active US8072760B2 (en) 2006-04-27 2010-04-14 Power inverter
US20120106087A1 (en) * 2010-11-02 2012-05-03 Abb Technology Ag Base plate
US6960278B2 (en) 2001-09-21 2005-11-01 Alstom Method of improving the properties of adhesion of a non-oxide ceramic substrate before gluing it
US6978856B2 (en) 2002-04-18 2005-12-27 Hitachi, Ltd. Electrical apparatus, cooling system therefor, and electric vehicle
US7031161B2 (en) 2003-06-04 2006-04-18 Vacon Oyj Cooling system for adjustable electric drive
US20080049476A1 (en) 2006-07-21 2008-02-28 Hitachi, Ltd. Electric Power Converter
US7090044B2 (en) 2002-04-18 2006-08-15 Hitachi, Ltd. Electrical apparatus, cooling system therefor, and electric vehicle
US8897015B2 (en) * 2010-11-02 2014-11-25 Abb Technology Ag Base plate
EP1858313B1 (en) 2013-09-11 grant
CN101783579A (en) 2010-07-21 application
EP1858313A1 (en) 2007-11-21 application
CN101064289B (en) 2010-06-09 grant
CN101783579B (en) 2012-08-08 grant
US20070253164A1 (en) 2007-11-01 application
US20110032676A1 (en) 2011-02-10 application
US7710721B2 (en) 2010-05-04 grant
JP4857017B2 (en) 2012-01-18 grant
JP2007295765A (en) 2007-11-08 application
CN101064289A (en) 2007-10-31 application
US20030067748A1 (en) 2003-04-10 Water cooled inverter
US7042725B2 (en) 2006-05-09 Power switching module and inverter equipped therewith