Power conversion device

Patent metadata

Field	Value
Publication number	US-2016211741-A1
Application number	US-201414915290-A
Country	US
Kind code	A1
Filing date	Sep 1, 2014
Priority date	Sep 10, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A power conversion device is capable of achieving three requirements to restrict a surge voltage, ensure high radiation performance of SW elements, and restrict ringing at the same time. In a power conversion device, element modules of two SW elements are stacked in a thickness direction via an insulating layer in such a manner that lateral surfaces are aligned parallel to each other in a same orientation, and a positive terminal of one SW element and a negative terminal of the other SW element are disposed so as to overlap each other in the thickness direction.

First claim

1 . A power conversion device comprising two serially-connected switching elements (hereinafter, referred to as SW elements) of an upper and a lower arm, the power conversion device supplying power to a load from a connection point of the two SW elements by converting a voltage and a current from a DC power supply,
wherein:
each of the two SW elements is provided by an element module which is molded with resin in a shape of a flat rectangular parallelepiped;
the element module includes a heat sink connected to a positive electrode of the SW element and a heat sink connected to a negative electrode of the SW element, the heat sink connected to the positive electrode is disposed on a flat surface of the flat rectangular parallelepiped so that an outer surface thereof is exposed, and the heat sink connected to the negative electrode is disposed on an opposite flat surface of the rectangular parallelepiped so that an outer surface thereof is exposed;
the element module includes a positive terminal coupled to the heat sink connected to the positive electrode and a negative terminal coupled to the heat sink connected to the negative electrode, and the positive electrode and the negative electrode are extracted from a lateral surface of the flat rectangular parallelepiped without overlapping in a thickness direction of the flat rectangular parallelepiped; the element modules of the two SW elements are stacked in the thickness direction via an insulating layer in such a manner that the lateral surface of one of the two SW elements and the lateral surface of the other of the two SW elements are aligned parallel to each other in a same orientation, and the positive terminal of the one of the two SW elements and the negative terminal of the other of the two SW elements are disposed to overlap each other in the thickness direction; in one set of the positive terminal and the negative terminal disposed to overlap, the positive terminal and the negative terminal are electrically connected in a vicinity of the lateral surfaces of the two SW elements to provide an output terminal to be connected to the load; and in the other set of the positive terminal and the negative terminal disposed to overlap, the positive terminal of the SW element of the upper arm provides a high-potential terminal to be connected to a high potential side of the DC power supply and the negative terminal of the SW element of the lower arm provides a low-potential terminal to be connected to a low potential side of the DC power supply.

2 . The power conversion device according to claim 1 , wherein:
the positive terminal and the negative terminal disposed to overlap are in a locational relation such that either one covers the other in the thickness direction.

3 . The power conversion device according to claim 1 , wherein:
the element modules of the two SW elements are of a same structure.

4 . The power conversion device according to claim 1 , wherein:
the positive terminal and the negative terminal are extracted from the lateral surface at a same height in the thickness direction.

5 . The power conversion device according to claim 4 wherein:
the positive terminal and the negative terminal are extracted from one of two regions divided in the thickness direction by a bisector.

6 . The power conversion device according to claim 1 , wherein:
a spacer to fix an interval in the thickness direction is inserted between the positive terminal and the negative terminal disposed to overlap.

7 . The power conversion device according to claim 1 , wherein:
a groove extending through the lateral surface in the thickness direction is provided between the positive terminal and the negative terminal.

8 . The power conversion device according to claim 1 , wherein:
a signal line connected to a control electrode of the SW element is extracted from another lateral surface opposing the lateral surface.

9 . The power conversion device according to claim 8 , wherein:
the signal line is extracted from the another lateral surface in one of two regions divided by a bisector in a direction orthogonal to the thickness direction.

10 . The power conversion device according to claim 1 , wherein:
in the other set of the positive terminal and the negative terminal, a snubber circuit having a capacitor element is electrically connected adjacent to the lateral surface between the positive terminal and the negative terminal.

11 . The power conversion device according to claim 10 , wherein
the snubber circuit includes:
a metal member having a current path with substantially a U-shape between the positive terminal and the negative terminal and formed with a cut portion at a midpoint; and
the capacitor element of a surface-mount type, electrodes of which are connected to opposite sides of the cut portion.

12 . The power conversion device according to claim 11 , wherein:
a resistor is connected to the capacitor element in series.

13 . The power conversion device according to claim 12 , wherein:
the resistor is formed of a surface-mounted resistor element; and electrodes of the resistor are connected to opposite sides of a cut portion provided to the metal member at a position different from the cut portion to which the capacitor element is connected.

14 . The power conversion device according to claim 12 , wherein:
the resistor is formed of a trimmed resistor portion a sectional area of which is reduced at a midpoint of the current path by making an incision to the metal member.

15 . The power conversion device according to claim 1 , wherein:
the element modules of the two SW elements have a structure in which the element modules are disposed between water-cooling coolers via an insulating layer.

16 . The power conversion device according to claim 1 , wherein:
the power conversion device is employed in a vehicle.

Assignees

• Denso Corp

Inventors

• Ishino Hiroshi
• Jinsei Yousuke
• Ikegame Atsushi

Classifications

• H10W90/763

  between laterally-adjacent chips · CPC title

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W72/932

  Plan-view shape, i.e. in top view · CPC title

• H10W72/652

  comprising metals or metalloids, e.g. silver · CPC title