JPS6225820A - Semicondcutor converter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a semiconductor conversion device, and particularly to a fuse blowout detection device that is suitable for protecting semiconductor elements.

[Background of the invention]

As shown in Figure 3, conventional fuse blowing detection in semiconductor converter devices is known in which a bird installed in series with the semiconductor element detects the fuse blowing from a mechanism and sends the signal to the outside as a contact signal. . For this reason, it is not possible to monitor the number of blown fuses, and since the detection circuit is composed of a-contacts, it is difficult to detect a failure of the contact or a failure when the contact resistance increases. 7 is a control power supply,
8 is a relay, and 9 is a thyristor bridge circuit.

(Reference Denkishoin [Introduction to Thyristor Application Technology] vol.
40) [Object of the Invention] The object of the present invention is to provide a display or a signal indicating the number of fuses blown when a fuse blows, while monitoring whether the protective fuses of a semiconductor conversion device are maintained in a normal state. be.

(Summary of the Invention) The main point of the present invention is that a device fuse breaker composed of a plurality of semiconductor elements is provided with a voltage detection relay in series with the B contact of the contact via a current limiting resistor, thereby detecting the normal state of the fuse. And the number of fuses blown is behind.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the main circuit configuration of one embodiment.

FIG. 1 shows a semiconductor conversion device 12 in which a thyristor bridge circuit 9 is connected in parallel with a thyristor bridge circuit 9 comprising a high-speed current-limiting fuse 10 connected in series with a thyristor element 11, and a semiconductor converter 12 in which the fuse blower has a contact 1. Of these, the contacts of the fuse breaker of the thyristor bridge circuit 9 are connected in series, and the circuit via the limiting current resistor 2 is connected in parallel for each bridge, and is connected to the voltage detection relays 3 and 4. be.

Voltage detection relays 3 and 4 are voltage detection relays that have the same internal resistance, but have different voltage detection levels.

When full high speed current limiting fuse 10 is normal, voltage detection relay 3
Since the voltage applied to and 4 becomes the maximum voltage because all limiting current resistors 2 and 3 are connected in parallel through contact 1, the voltage detection level of voltage detection relay 3 is adjusted to operate at the voltage value at this time. Set.

Also, when a fuse in one parallel circuit in the parallel semiconductor converter blows out, the limiting current resistor 2 of the blown circuit is disconnected by the trigger contact that operates when the fuse blows, and the voltage applied to the voltage detection relays 3 and 4 decreases. Therefore, the voltage detection level of the voltage detection relay 4 is set to operate at the voltage value at this time.

As described above, when the high-speed current limiting fuse is normal, the voltage detection relay 3 operates, and when the fuse of one parallel circuit in the parallel semiconductor converter is blown, the voltage detection relay 4 operates, so that the fuse is in the normal state. It is also possible to monitor whether the fuse is blown or not. Furthermore, by configuring the detection circuit at point b, it is possible to reliably detect failures in the trigger contact or failures when contact resistance increases, thereby improving the reliability of the protection device.

Next, in FIG. 2, the voltage detection relay 5 is added to the detection circuit of FIG.
6 shows the added detection circuit. The voltage detection level of the voltage detection relay 5 is set to operate when any two parallel group fuses among the n parallel semiconductor converters are blown, and when the three parallel group fuses are blown, the voltage detection relay 6 is operated. Set it as follows.

In this way, by increasing the number of voltage detection relays (n
-1) Fuse blowout can be detected up to the group.

〔Effect of the invention〕

According to the present invention, while monitoring whether the protective fuse of a semiconductor conversion device maintains a normal state, displaying the number of circuits having a blown fuse when the fuse blows, or
This is particularly effective when a parallel circuit is provided.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention, FIG. 2 is a diagram of a similar example for detecting fuse blowing in a parallel bridge circuit in an n-parallel semiconductor converter, and FIG. 3 is a diagram of a similar example. It is a conventional fuse blowout detection circuit diagram. 1...Trigger contact or switch, 2...Limiting current resistance. 3 to 6... Voltage detection relays with different voltage detection levels,
7... Control power supply, 8... Relay, 9... Thyristor bridge circuit, 10... High speed current limiting fuse, 11...
...Thyristor element, 12...Semiconductor conversion device.

Claims (1)

[Scope of Claims] 1. A semiconductor conversion device comprising a semiconductor element and a high-speed fuse with a fuse-blower connected in series to the semiconductor element and a contact, wherein the fuse-blower is connected in series to the contact and detects a plurality of voltages. 1. A semiconductor converter device comprising a relay and monitoring the normal state of a fuse and displaying the number of blown fuses or giving a signal.