JPH0541562Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cooling body for power semiconductor devices.

[Conventional technology and its problems]

The snubber circuit of a gate turn-off thyristor (hereinafter referred to as a GTO thyristor) consists of a series circuit of a snubber diode 2 and a snubber capacitor 3 connected in parallel with the GTO thyristor 1, as shown in Fig. 5, and a snubber circuit as a discharge resistance of the snubber capacitor 3. It is formed by connecting a snubber resistor 4 in parallel with the diode 2. In such a circuit, the inductance ls
is the wiring inductance of the series circuit of GTO thyristor 1, snubber diode 2, and snubber capacitor 3.

When the gate of the GTO thyristor 1 is turned off, a spike voltage is generated in the wiring inductance ls, and this voltage is applied between the anode and cathode of the GTO thyristor 1. If such a spike voltage is large, it will damage the GTO thyristor 1, so the wiring inductance ls needs to be as small as possible (for example, 0.4 μH or less).

On the other hand, GTO thyristor 1 and snubber diode 2 each require a cooling body, but since large-capacity (2.5 KV 1 KA or more) GTO thyristors are usually flat and snubber diode 2 is stud-shaped, conventionally they have been separated separately. Cooling was performed using air-cooled cooling fins.

If cooling fins are provided separately for the GTO thyristor 1 and the snubber diode 2 in this way, the entire device occupies space. Moreover, especially in the case of a GTO thyristor, as mentioned above, if the thyristor is separated from other elements, the wiring inductance on the circuit increases, which is not preferable.

In addition, as a common cooling fan attached to the GTO thyristor and other elements,
Although there is a Japanese Patent No. 23895, it is difficult to miniaturize air-cooled cooling fins because they are large. Also, due to its shape, it is not suitable for mounting stud-type semiconductor devices.

The purpose of the present invention is to eliminate the disadvantages of the conventional example,
It is an object of the present invention to provide a cooling body for a semiconductor element that can further reduce the overall size and minimize wiring inductance between a GTO thyristor and a snubber diode.

[Means for solving problems]

In order to achieve the above-mentioned object, the gist of the present invention is that a circular oblong groove for inserting a flat gate turn-off thyristor and a threaded hole for a stud-type snubber diode are formed in a water-cooled cooling body.

[Effect]

According to the present invention, a water-cooled cooling body that can be made smaller than an air-cooled cooling fin is used, and moreover, the anodes of the GTO thyristor and the snubber diode can be commonly cooled with one water-cooled cooling body. the result,
The wiring inductance of the GTO thyristor and snubber diode can be reduced.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view showing one embodiment of the cooling body for semiconductor devices of the present invention, and FIG. 2 is a side view of the same, in which 5 indicates a flat plate having a cooling water inlet 5a and an outlet 5b. A rectangular parallelepiped water-cooled cooling body is shown.

A circular flat groove 6 for inserting a flat GTO thyristor is formed on the upper surface of this water-cooled cooling body 5, and a stud-type snubber diode is formed on the side other than where the inlet 5a and the outlet 5b are located, for example, on the opposite side. A screw hole 7 having a female thread into which the screw can be inserted is formed.

3 and 4 show a state in which a stud type snubber diode 2 is attached to such a water-cooled cooling body 5. If the polarity of the internal semiconductor element of the stud type snubber diode is opposite to that shown in Figure 1 above, screw the cathode electrode of this snubber diode to the water-cooled body of the present invention on the cathode side of the GTO thyristor. Just put it in.

[Effect of idea]

As mentioned above, the semiconductor device cooling body of the present invention has a water-cooled cooling body structure that can cool both the flat GTO thyristor and its stud snubber diode, so the wiring inductance between the GTO thyristor and the snubber diode can be reduced. This makes it possible to easily reduce the spike-like voltage that occurs when the gate of the GTO thyristor is turned off to a permissible value or less.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one embodiment of the semiconductor device cooling body of the present invention, Fig. 2 is a side view of the same, Fig. 3 is a plan view of the same with a snubber diode attached, and Fig. 4 is the same as the above. The side view, FIG. 5, is a circuit diagram showing the GTO thyristor and its snubber circuit. 1... GTO thyristor, 2... Snubber diode, 3... Snubber capacitor, 4... Snubber resistor, 5... Water cooling body, 5a... Inlet, 5b...
...Spout, 6...Circular flat groove, 7...Screw hole.

Claims (1)

[Scope of utility model registration request] 1. A cooling body for a semiconductor device, characterized in that the water-cooled cooling body is formed with a circular flat groove for inserting a flat gate turn-off thyristor and a screw hole for a stud-type snubber diode.