JPH10322804A - Power converter - Google Patents

Abstract

(57) [Summary] [PROBLEMS] Two sets of common DC power supply input circuits
Two conversion circuits are provided side by side to drive each load. The power conversion device is configured such that when an auxiliary power supply circuit connected to a gate circuit between a GTO thyristor and a capacitor discharging thyristor is stopped, power supply switching means stops power supply switching means. The disconnecting contactor 15A connected to the converter 5A on the circuit side is opened, and the gate circuit 6 is switched to the other sound auxiliary power supply circuit 16B for connection, and only the remaining sound converter 5B is continued. Operate both loads 9A, 9B
Supply conversion power to

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a power converter.

[0002]

2. Description of the Related Art Conventionally, two converters are provided, each of which supplies an output individually to a load, and when one of the converters fails, a contactor on the output side is switched to switch from a sound converter. FIG. 7 shows a configuration of a power converter that supplies an output to both loads simultaneously.

In this conventional power converter, DC power collected from a pantograph 1 is converted into converters 5A and 5B via contactors 2A and 2B, reactors 3A and 3B, and resistors 4A and 4B.
I try to enter each. And contactor 2
When reactors A and 2B are charged, reactors 3A and 3
B, converters 5A, 5B through charging resistors 4A, 4B
Each input capacitor (not shown) is charged. When this charging is completed, the gate circuits 6A and 6B cause G
Each of the TO thyristors 7A and 7B is turned on to short-circuit each of the charging resistors 4A and 4B, and supply of DC power to the converters 5A and 5B is started.
Is supplied to the loads 9A and 9B via the output side contactors 8A and 8B.

In this conventional power converter, thyristors 10A, 1A are provided on the input sides of converters 5A, 5B, respectively.
0B and resistors 11A, 1A for limiting the current when each of these thyristors 10A, 10B is turned on.
1B, and voltage detectors 12A and 12B for detecting the input voltages of the converters 5A and 5B, respectively. Further, a contactor 13 for connecting the input sides of the loads 9A and 9B is provided on the input sides of the loads 9A and 9B, and one of the conversion units 5A and 5B, for example, the conversion unit 5 is provided.
When A stops, the contactor 8A on the output side is turned off and the contactor 13 is turned on to supply power to the load 9A from the healthy converter 5B side.

[0005]

However, such a conventional power converter not only includes two converters but also two DC input circuits having almost the same configuration. There was a problem that the size became large as a whole.

The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a power converter that can be downsized by using a single DC input circuit.

[0007]

According to a first aspect of the present invention, there is provided a power converter, wherein converters are juxtaposed so as to share a power input system, and a first gate circuit of each of the juxtaposed converters. , A disconnecting contactor inserted on the input side of each of the juxtaposed converters, and detecting the stop of the gate power circuit of each of the juxtaposed converters. And a converter disconnection control unit that opens the disconnection contactor connected to the conversion unit on the side.

In the power converter according to the first aspect of the present invention,
In a normal state, the converters arranged in parallel with the power input system convert the power input and supply the converted power to the respective loads. If the gate power supply circuit of the other conversion unit fails, the conversion unit disconnection control unit opens the converter disconnection contactor that is connected to the stopped gate power supply circuit, disconnects it from the power input system, and disconnects from the power input system. Supply the converted power to both loads.

According to a second aspect of the present invention, in the power conversion device of the first aspect, the switching element for discharging a charge of an input capacitor connected to an input side of the conversion unit when the conversion unit performs a protection operation. A second gate circuit that performs gate control; and a power supply switching unit that connects the second gate circuit to any of the gate power supply circuits. The conversion unit disconnection control unit includes a second gate circuit that controls the second gate circuit. Upon detecting the stop of the connected gate power supply circuit, the disconnecting contactor connected to the converter on the side of the stopped gate power supply circuit is opened, and the second gate circuit is sounded by the power supply switching means. This is switched to another gate power supply circuit side to be connected.

[0010] In the power converter according to the second aspect of the present invention,
When the gate power supply circuit connected to the second gate circuit stops, the power switching means opens the disconnecting contactor connected to the converter on the side of the stopped gate power supply circuit and makes the second gate circuit sound. Connected to another gate power supply circuit side, and continuously operates only the remaining healthy converters to supply converted power to both loads.

According to a third aspect of the present invention, in the power converter of the first aspect, a second gate circuit for performing a gate control of a self-extinguishing type switching element for short-circuiting a charging resistor included in the power supply input system. Power supply switching means for connecting the second gate circuit to any of the gate power supply circuits, wherein the conversion unit disconnection control unit is provided for the gate power supply circuit connected to the second gate circuit. When the stoppage is detected, the power supply switching means switches the second gate circuit to one of other sound gate power supply circuits and connects it.

In the power converter according to the third aspect of the present invention,
When the gate power supply circuit connected to the second gate circuit is stopped, power supply switching means switches the second gate circuit from the stopped gate power supply circuit to the gate circuit of any of the converters. Switch to a proper gate power supply circuit and connect to continue operation.

According to a fourth aspect of the present invention, there is provided a power conversion device, wherein the conversion units are provided side by side so as to share a power supply input system, and the power conversion system is provided with the power supply input system for extending an operation time when power is interrupted. An input filter capacitor, a switching element for discharging a charge of an input capacitor connected to an input side of the conversion unit and a charge of the input filter capacitor when the conversion unit performs a protection operation, and the conversion unit arranged in parallel. Disconnecting contactors inserted on the input side of each section,
A contactor coil that opens and closes each of the disconnecting contactors, a circuit in which a resistor and a capacitor are connected in series and connected in parallel with the contactor coil, and detects any failure of the converter. A converter disconnection control unit for turning on the switching element and cutting off the power supply to the contactor coil for the disconnection contactor connected to the failed converter.

In the power converter according to the fourth aspect of the present invention,
If one side of the converter fails, the power to the contactor coil for the disconnecting contactor is cut off and the contactor is opened, but before that, the switching element for discharging the capacitor is turned on and converted to the input filter capacitor. Discharge the input capacitor of the unit. At this time, a charge is continuously supplied to the contactor coil from a series circuit of a capacitor and a resistor connected in parallel to the contactor coil of the disconnecting contactor to temporarily delay the release time of the contactor coil. While the release time is extended, the charge of the input filter capacitor and the input capacitor of the converter is completely discharged through the switching element for discharging the capacitor, and then the disconnector is opened by opening the contactor to disconnect the failed converter.

Thus, when disconnecting the failed converter by opening the disconnecting contactor on the input side, no overcurrent flows through the main contact of the disconnecting contactor.

According to a fifth aspect of the present invention, there is provided a power conversion device, wherein the conversion units are provided side by side so as to share a power supply input system, and the power conversion system is provided with the power supply input system for extending operation time when power supply is interrupted. An input filter capacitor, a switching element for discharging a charge of an input capacitor connected to an input side of the conversion unit and a charge of the input filter capacitor when the conversion unit performs a protection operation, and the conversion unit arranged in parallel. A first disconnecting contactor inserted at the input side of each of the sections, a second disconnecting contactor inserted between an intermediate point of the input capacitor of the conversion section and an intermediate point of the input filter capacitor, A circuit in which a contactor coil for opening and closing each of the first and second disconnecting contactors and a resistor and a capacitor connected in parallel with the contactor coil are connected in series. The contactor coil for each of the first and second disconnecting contactors connected to the converter where the failure has occurred, detecting the failure of one of the converters and turning on the switching element; And a conversion unit disconnection control unit that cuts off current to the power supply.

In the power converter according to the fifth aspect of the present invention,
When one side of the converter fails, the first and second disconnecting contactors are cut off by energizing the contactor coil for the first and second disconnecting contactors to open the first and second disconnecting contactors. Of the input filter capacitor and the input capacitor of the converter are discharged. At this time, a charge is continuously supplied to the contactor coil from a series circuit of a capacitor and a resistor connected in parallel to the contactor coil of the first and second disconnecting contactors, and the release time of the contactor coil is reduced. Temporarily delayed, while the release time was extended, the input filter capacitor and the input capacitor of the conversion unit were completely discharged through the switching element for capacitor discharge, and then disconnected and the contactor was opened to cause failure. Disconnect the converter. Thus, when disconnecting the failed converter by opening the disconnecting contactor on the input side, no overcurrent flows through the main contact of the disconnecting contactor.

Further, since the intermediate point of the input filter capacitor is connected to the intermediate point of each input capacitor of the converter, if a short-circuit fault occurs in one converter, the input filter capacitor is also simultaneously shifted from the intermediate point to one side. Is short-circuited, and at the same time, the switching element for discharging the capacitor is turned on to discharge the charge of the capacitor. Therefore, the voltage of the input filter capacitor is suppressed to the capacitor voltage on one side that is not short-circuited.Abrupt charge transfer from the input filter capacitor does not occur on the non-short-circuited side of the input capacitor on the converter side, and the voltage of the input capacitor is reduced. There will be no more than when the failure occurs, and no overvoltage will be applied to the input capacitor on the side that is not short-circuited.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a circuit according to a first embodiment of the present invention.
For each of the two converters 5A and 5B arranged side by side,
In the input circuit that inputs the DC power from the pantograph 1,
Contactor 2, reactor 3, charging resistor 4, GTO thyristor 7 for short-circuiting charging resistor 4, and electric charge of input capacitors 5A1, 5A2; 5B1, 5B2 when each of converters 5A, 5B performs protection operation. A thyristor 10 for discharging the thyristor, a current limiting resistor 11 for limiting a current flowing through the thyristor 10, and a voltage detector 12 for detecting a voltage between both ends of the thyristor 10 are provided in common. The DC power of the DC input circuit is separated from each of the converters 5A and 5B, and the contactors 15A and 5B are separated.
A, 15B.

The output side circuits for the loads 9A and 9B of the converters 5A and 5B have the same configuration as that of the conventional example shown in FIG. 7, and the converted AC power of the converters 5A and 5B is supplied via the contactors 8A and 8B. Contactor 1 for supplying power to each of the loads 9A and 9B, and for switching the power supply system so as to receive power from the other converter when one converter is stopped.
3 is connected to the input side of loads 9A and 9B.

The power converter of this embodiment also has a gate circuit power supply 16A (AVR1), 1 for driving a gate circuit (not shown) of each of the converters 5A, 5B.
6B (AVR2) and a control unit 17A (CTR) for performing gate control of the GTO thyristor 7 and the thyristor 10.
-A) and 17B (CTR-B).

The control unit 17A is connected with a coil 20 for operating the contactor 2 on the DC input circuit and a coil 15C for operating the contactor 15A of the DC input section of the converter 5A. The control unit 17B is connected with a relay 18 for switching relay contacts 18a and 18b, which will be described later, a coil 15D for operating a contactor 15B of a DC input unit of the converter 5B, and a coil 20 of the contactor 2. The gate circuit power supply 16A has a b-contact 18 of the relay 18.
b and a gate circuit (not shown) of the conversion unit 5A are connected, and the a contact 1 of the relay 18 is connected to the gate circuit power supply 16B.
8a and a gate circuit (not shown) of the conversion unit 5B are connected.

Next, the operation of the power converter of the first embodiment having the above configuration will be described. Normally, the relay 18 is off, and the power supply 16A for the gate circuit is connected to the gate circuit 6 and the gate circuit (not shown) of the converter 5A via the b contact 18b. The contactor 13 is in an open state, the contactors 8A and 8B are in a closed state, and the outputs of the converters 5A and 5B are supplied to the loads 9A and 9B, respectively. The gate circuit 6 turns off both the GTO thyristor 7 and the thyristor 10.

In this state, the control unit 17A
When 0 is operated, the contactor 2 is closed and the DC power from the pantograph 1 is changed to the contactor 2, the reactor 3,
The input capacitors 5A1, 5A2; 5B are supplied to the conversion units 5A, 5B through the charging resistor 4, respectively.
1,5B2 is charged. When the charging is completed, the gate circuit 6 turns on the GTO thyristor 7, short-circuits the charging resistor 4, supplies DC power to each of the converters 5A and 5B, and the converters 5A and 5B perform DC-AC conversion. The supply of AC power to each of the loads 9A and 9B is started.

If one of the gate circuit power supplies 16A fails, a failure signal 21A of the gate circuit power supply 16A is input to the control unit 17A. This failure signal 21A
The control unit 17A receives the power supply 16 for the gate circuit.
The failure signal of A is output to the control unit 17B as the gate power failure signal 22A. The control unit 17A further operates the circuit according to the failure sequence when the failure signal 21A is received, but outputs the lockout signal 23A if the failure state is still not recovered.
Output to B.

In response, the control unit 17B drives the relay 18 with the logic shown in FIG. 2, that is, with the AND logic of the failure signal 22A and the lockout signal 23A. As a result, the relay 18 switches the connection from the relay b contact 18b to the relay a contact 18a, and the gate power of the GTO thyristor 7 and the thyristor 10 is changed from the gate circuit power 16A to 1
6B.

At the same time, the control unit 17A temporarily stops the contactor coil 20 to open the contactor 2, and activates the disconnector contactor coil 15C to disconnect the contactor 15A to open the converter 5A. Disconnect from DC input circuit. The contactor 8A is in an open state on the output side of the converters 5A and 5B, and the switching contactor 13A
Is closed.

Thus, the DC power from the pantograph 1 is supplied only to the converter 5B, and the loads 9A,
9B is supplied with power from the converter 5B at the same time.

As described above, in the power converter of the first embodiment, the two converters 5A and 5B
In a power converter in which DC power is supplied by a common set of DC input circuits, even if one of the conversion units 5A or 5B is stopped, only the sound conversion unit side is continued. Thus, power can be supplied to both loads 9A and 9B, so that a single DC input circuit can be used to simplify the circuit configuration and reduce the size.

Next, a power converter according to a second embodiment of the present invention will be described with reference to FIG. The second embodiment has a configuration in which one power supply for a gate circuit is added to the power converter of the first embodiment shown in FIG.
A gate circuit power supply 16A dedicated to the gate circuit 6 with the O-thyristor 7 and the thyristor 10, a gate circuit power supply 16B for the gate circuit of the conversion unit 5A, and another gate circuit for the gate circuit of the conversion unit 5B A power supply 16C is provided, and a relay 24 is provided. The power supply 16B for the gate circuit is connected to the a contact 1 of the relay 18 by the b contact 24b.
The gate circuit power supply 16C is connected to the a contact 18a of the relay 18) by the a contact 24a. The relay 18 and the added relay 24 are connected to the control unit 17B by the power supply 16 for the gate circuit.
When the stop of A is detected, the relay 18 is operated, and when the control unit 17B further detects the stop of the gate circuit power supply 16B, the relay 24 is operated.

Next, the operation of the power converter of the second embodiment having the above configuration will be described. Normally, the relays 18 and 24 are both off, the gate circuit power supply 16A is connected to the gate circuit 6 via the relay b contact 18b, and the gate circuit power supply 16B is connected to the gate circuit of the converter 5A via the relay b contact 24b. (Not shown), and a gate circuit power supply 16C is connected to a gate circuit (not shown) of the converter 5B. The state of other parts is 1st
This is the same as the embodiment.

In this state, the control unit 17A
When 0 is operated, the contactor 2 is closed and the DC power from the pantograph 1 is changed to the contactor 2, the reactor 3,
The input capacitors 5A1, 5A2; 5B are supplied to the conversion units 5A, 5B through the charging resistor 4, respectively.
1,5B2 is charged. When the charging is completed, the gate circuit 6 turns on the GTO thyristor 7, short-circuits the charging resistor 4, supplies DC power to each of the converters 5A and 5B, and the converters 5A and 5B perform DC-AC conversion. The supply of AC power to each of the loads 9A and 9B is started.

If the gate circuit power supply 16A fails, a failure signal 21A of the gate circuit power supply 16A is input to the control unit 17A. Upon receiving the failure signal 21A, the control unit 17A outputs a failure signal of the gate circuit power supply 16A to the control unit 17B as a gate power supply failure signal 22A. The control unit 17A further operates the circuit in accordance with the failure sequence when receiving the failure signal 21A, but outputs the lockout signal 23A to the control unit 17B if the failure state is still not recovered.

In response to this, the control unit 17B issues a failure signal 22A and a lockout signal 23A as shown in FIG.
The relay 18 is driven by the two-input AND logic 25, and the connection is switched from the relay b contact 18b to the relay a contact 18a, and the gate power of the GTO thyristor 7 and the thyristor 10 is changed from the gate circuit power 16A to the gate circuit power 16B.
Switch to.

The operation thereafter is the same as that of the first embodiment, and the DC power from the pantograph 1 is supplied only to the converter 5B, and the power is supplied from the converter 5B to the loads 9A and 9B. It will be supplied at the same time.

When the power supply 16A for the gate circuit is stopped, and the power supply 16B for the gate circuit is also stopped, a failure signal 21B is input to the control units 17A and 17B. The failure signal 21B for the power supply 16B for use
A is output to the control unit 17B. Further, upon receiving the failure signal 21B, the control unit 17A performs a circuit operation in accordance with the failure sequence, and outputs a lockout signal 23A to the control unit 17B if the failure state is still not recovered.

Therefore, as shown in FIG. 4, the control unit 17B outputs a failure signal 21B from the gate circuit power supply 16B.
The relay 24 is driven by a three-input AND logic 26 of a failure signal 22A and a lockout signal 23A from the control unit 17A, and a relay a contact 2
The connection is switched to 4a, and the gate power of the GTO thyristors 7 and 10 is further switched from the gate circuit power supply 16B to the gate circuit power supply 16C.

As a result, the gate circuit 6 of the GTO thyristor 7 and the thyristor 10 and the sound conversion unit 5 can be operated by one of the gate circuit power supplies 16C added in the second embodiment.
B to supply power to the gate circuit and load 9
Power will continue to be supplied to both A and 9B.

Thus, in the power converter according to the second embodiment, the two converters 5A and 5B
In a power converter in which DC power is supplied by a common set of DC input circuits, even if one of the conversion units, for example, the conversion unit 5A is stopped, a sound conversion unit 5B Both loads 9A, 9
B can continue to be supplied with power, and therefore a single DC input circuit is used to simplify the circuit configuration and reduce the size.

Next, a third embodiment of the present invention will be described with reference to FIG. The power converter according to the third embodiment is different from the power converter according to the first embodiment shown in FIG. 1 in that an input filter capacitor 31 for further extending the operation time when power is interrupted is provided in a DC input circuit. Unit 1
In parallel with the disconnecting contactor coils 15C, 15D controlled by respective 7A, 17B, resistors 32A,
There is provided a circuit in which 32B and capacitors 33A and 33B are connected in series. Further, voltage detectors 12A and 12B are provided in parallel with the input capacitors 5A1 and 5A2; 5B1 and 5B2 to detect the input side voltages of the converters 5A and 5B, respectively.

In the third embodiment, the GTO
Thyristor 7, input capacitors 5A1, 5A2; 5B
The gate circuit 6 for controlling the gates of the thyristors 10 for discharging the electric charge of 1, 5B2 and the power supply for the gate circuit are not shown.
This embodiment is the same as the configuration of the second embodiment.

Next, the operation of the third embodiment having the above configuration will be described. Normally, both converters 5A and 5B operate to convert DC input to AC and supply them to loads 9A and 9B, respectively, as in the first and second embodiments.

If the main circuit element inside the converter 5A is short-circuited, one of the input capacitors 5A1 and 5A2 is short-circuited. If this capacitor short circuit occurs, it is detected by the voltage detector 12A and the control unit 1
The output signal is input to 7A. The control unit 17A receives this signal and sends a failure signal 35A to the control unit 17B.
And the control unit 17B turns off the gate-on signal of the GTO thyristor 7 and outputs a gate-on signal to the thyristor 10 at the same time. The contactor 2 is also opened by cutting the output to the coil 20, and the output to the contactor coil 15C is also cut. The disconnecting contactor 15A is set to the open state by this output cut, but there is a predetermined delay before the disconnecting contactor 15A enters the open state as described later.

When the thyristor 10 is turned on, the converter 5A,
5B each input capacitor 5A1, 5A2; 5B
1, 5B2 and the charges stored in the input filter capacitor 31 are all thyristors 10
Through the resistor 11. Control unit 17A
Is separated after the discharge of this capacitor.
To open the contactor 15A in the open state,
The converter 5A is disconnected together with the input capacitors 5A1 and 5A2.

Thereafter, the control unit 17A again energizes the contactor coil 20 to bring the contactor 2 into the closed state.
As a result, the operation of only the healthy converter 5B is restarted, and AC power is supplied from the converter 5B to each of the loads 9A and 9B.

When the converter 5A is stopped in this manner, the power supply for the gate circuit (not shown; the power supply 16A in FIG. 1)
Is turned off, the input capacitors 5A1 and 5A2 are rapidly charged by the charge of the input filter capacitor 31 in the separated converter 5A, and the charges are transferred to the capacitors 31, 5A1 and 5A2 and the disconnecting contactor 15A. Electric current flows. Therefore, in order to prevent this, resistors 32A and 32B and capacitors 33A and 3 are connected in parallel with coils 15C and 15D of disconnecting contactors 15A and 15B, respectively.
By providing a circuit in which the contactor 3B is connected in series, when the control unit 17A disconnects and cuts off the power supply to the contactor coil 15C and tries to open the contactor 15A, the release time after the power supply cutoff is extended. During this time, an ON signal is output from the control unit 17B to the thyristor 10 and the input filter capacitor 3
1 and the input capacitors 5A1 and 5A2 are discharged. After the discharge, the disconnecting contactor 15A is opened, and no overcurrent flows to the main contact of the disconnecting contactor 15A.

When a short-circuit fault occurs on the conversion unit 5B side, the voltage detector 12B inputs a short-circuit signal to the control unit 17B, and the same operation as described above is executed in the B system, so that the conversion unit 5B side operates. Is separated by the contactor 15B, the operation of only the converter 5A on the sound side is continued, and power is supplied to both loads 9A and 9B.

As described above, according to the third embodiment, the DC input circuit is formed by a set of circuit elements common to the two converters 5A and 5B, as in the first and second embodiments. It can be configured to reduce the size and simplify the circuit.

Further, in the case of the third embodiment,
Although the input filter capacitor 31 is provided to stably supply AC power to the loads 9A and 9B without interruption even when the power supply is temporarily interrupted due to disconnection of the pantograph 1, the disconnecting contactor 15A Or contactor coil 15C or 1 for opening operation of 15B
Even if the power to 5D is cut off, it is immediately disconnected and contactor 15A
Or resistor 32 in parallel with these contactor coils 15C and 15D so that 15B does not open.
A, 32B and a series circuit of capacitors 33A, 33B are connected, and after the power is cut off from the control units 17A, 17B to the contactor coils 15C, 15D, a voltage is supplied from these capacitors 33A, 33B to the coils 15C, 15D. Since the time required for the disconnecting contactors 15A and 15B to be in the open state is delayed, the thyristor 10 is turned on before the disconnecting contactor 15A or 15B in the closed state is opened and the input filter capacitor is turned off. The charge of the input filter capacitor 31 can be prevented from being rapidly charged by discharging the charge of the input filter capacitor 31 and discharging the input capacitor 5A1, 5A2 or 5B1, 5B2 of the converter 5A or 5B that is disconnected due to the failure.

Next, a fourth embodiment of the present invention will be described with reference to FIG. The power converter according to the fourth embodiment includes two input filter capacitors 41 and 42 connected in series instead of the input filter capacitor 31 according to the third embodiment shown in FIG. 5A, 5
B, input capacitors 5A1, 5A2; 5B1,
5B2 is connected to the input filter capacitor 4
The contactor coils 15G and 15H which are connected to the connection points 1 and 42 via disconnecting contactors 15E and 15F and which control the opening / closing of these additionally provided disconnecting contactors 15E and 15F are provided. In this configuration, the coils 15C and 15D are connected in parallel. Further, in this way, between the connection point of the input capacitors 5A1 and 5A2 and the connection point of the input filter capacitors 41 and 42, and between the connection point of the input capacitors 5B1 and 5B2 and the connection point of the input filter capacitors 41 and 42. Are connected, the voltage detectors 12A1, 12A are used to detect the respective voltages of the input capacitors 5A1, 5A2, 5B1, 5B2.
2, 12B1 and 12B2 are provided. The other components are common to those of the third embodiment shown in FIG.

Next, the operation of the power converter of the fourth embodiment having the above configuration will be described. Normally, both converters 5A and 5B operate to convert DC input into AC and supply them to loads 9A and 9B, respectively, as in the third embodiment.

If the main circuit element inside the converter 5A is short-circuited, one of the input capacitors 5A1 and 5A2 is short-circuited. At this time, one of the input filter capacitors 41 and 42 is short-circuited at the same time.

If this capacitor short circuit occurs, it is detected by the voltage detector 12A1 or 12A2, and the output signal is input to the control unit 17A. The control unit 17A receives this signal and outputs a failure signal 35A to the control unit 17B, and the control unit 17B turns off the GTO thyristor 7 and simultaneously turns on the thyristor 10. Further, by cutting the output to the coil 20, the contactor 2 is also opened, and the contactor coil 15 is opened.
The output to C and 15G is also cut. The output contact cuts the disconnecting contactors 15A and 15E into an open state. As will be described later, the disconnecting contactors 15A and 15E are opened.
There is a predetermined delay before 15E becomes open.

When the thyristor 10 is turned on, the converter 5A,
5B each input capacitor 5A1, 5A2; 5B
All of the charge stored in the input filter capacitors 41 and 42 and the charge stored in the input filter capacitors 41 and 42 are discharged to the resistor 11 through the thyristor 10. After discharging the capacitor, the control unit 17A operates the disconnecting contactor coil 15C to disconnect the contactor 15A, thereby disconnecting the converter 5A together with the input capacitors 5A1 and 5A2.

Thereafter, the control unit 17A again energizes the contactor coil 20 to bring the contactor 2 into the closed state.
As a result, the operation of only the healthy converter 5B is restarted, and AC power is supplied from the converter 5B to each of the loads 9A and 9B.

When the converter 5A in which the short-circuit fault has occurred is stopped, the power supply for the gate circuit (not shown; FIG. 1)
Is turned off, the input capacitors 5A1 and 5A2 of the separated converter 5A are rapidly charged with the charges of the capacitors 41 and 42, and the capacitors 41, 42, 5A1 and 5A2 are turned off. And an overcurrent flows through the separation contactors 15A and 15E. Therefore, in order to prevent this, the detaching contactors 15A, 15E;
Coils 15C and 1 connected in parallel to B and 15F, respectively.
5G; 15D, 15H in parallel with each other, resistor 32
By providing a circuit in which A, 32B and capacitors 33A, 33B are connected in series, the control unit 17A disconnects and cuts off the power supply to the contactor coils 15C, 15G to disconnect and open the contactors 15A, 15E. When the power supply is cut off, the release time after the power supply cut can be extended. During this time, an ON signal is output from the control unit 17B to the thyristor 10 and the input filter capacitor 4
1, 42 and the capacitors 5A1 and 5A2 are discharged, and after this discharge, the disconnecting contactors 15A and 15E are opened, and no overcurrent flows through the main contacts of the disconnecting contactors 15A and 15E.

If a short-circuit fault occurs on the conversion unit 5B side, the voltage detector 12B1 or 12B2 inputs a short-circuit signal to the control unit 17B, and the same operation as described above is executed in the B-system. 5B side is separated and separated by the contactors 15B and 15F, and the converter 5A on the sound side is separated.
, And power is supplied to both loads 9A and 9B.

As described above, according to the fourth embodiment, similarly to the third embodiment, the DC input circuit is constituted by one set of circuit elements common to the two converters 5A and 5B. And the size and simplification of the circuit can be achieved, and the disconnecting contactor 15A, 15E or 15 in the closed state can be achieved.
The thyristor 10 is turned on to discharge the charge of the input filter capacitors 41 and 42 before B and 15F are opened, and the input capacitor 5A of the conversion unit 5A that is disconnected due to a failure.
A1, 5A2 or input capacitor 5B of conversion unit 5B
1, 5B2 can be prevented from being rapidly charged by the charges of the input filter capacitors 41, 42.

Further, in the fourth embodiment, the connection points of the input filter capacitors 41 and 42 and the input capacitors 5A1 and 5A2 of the converters 5A and 5B;
For example, the conversion unit 5
When a short-circuit fault occurs in the main circuit element of A, the input filter capacitor 41 or 42 is also short-circuited together with the input capacitor 5A1 or 5A2, and at the same time, the thyristor 10 is turned on to start discharging the charge of these capacitors. Therefore, the series voltage of the filter capacitors 41 and 42 can be suppressed to only the capacitor voltage on one side which is not short-circuited. Therefore, the filter capacitors 41 and 42 are connected to the input capacitor 5A1 or 5A2 on the non-short-circuited side in the converter 5A. There is no rapid charge transfer, the capacitor voltage does not rise more than when a short-circuit fault occurs, and the input capacitor 5 on the non-short-circuited side
There is no possibility that an overvoltage is applied to A1 or 5A2.

[0060]

As described above, according to the first aspect of the present invention,
If the gate power supply circuit of one of the converters fails, the converter disconnection control unit opens the converter contact disconnector that is connected to the stopped gate power supply circuit, disconnects it from the power input system, and disconnects it from the sound side. The conversion power can be supplied to both loads only by the conversion unit, and the power supply input system is shared by the two conversion units, so that the circuit configuration is small and simple.

According to the invention of claim 2, when the gate power supply circuit connected to the second gate circuit is stopped,
The power switching means opens the disconnecting contactor connected to the converter on the side of the gate power supply circuit that has stopped, and switches and connects the second gate circuit to another healthy gate power supply circuit side to connect the remaining sound power supply. Only the converter is operated continuously to supply the converted power to both loads, so that the power supply input system is shared by the two converters, so that the circuit configuration is small and simple.

According to the third aspect of the present invention, when the gate power supply circuit connected to the second gate circuit for controlling the gate of the self-extinguishing type switching element is stopped, the power supply switching means switches the second gate circuit. Since the circuit is switched from the stopped gate power supply circuit to one of the other sound gate power supply circuits and connected to continue the operation, the fault-tolerant performance of the gate power supply circuit can be improved.

According to the fourth aspect of the present invention, when one side of the conversion unit fails, the energization of the contactor coil to the disconnecting contactor is cut off to open the contactor, but before that, the capacitor for discharging the capacitor is used. Of the input filter capacitor and the input capacitor of the conversion unit by discharging the switching element, and at this time, the electric charge from the series circuit of the capacitor and the resistor connected in parallel to the contactor coil of the disconnecting contactor. Is continuously supplied to the contactor coil to temporarily delay the release time of the contactor coil, and during the extension of the release time, the charge of the input filter capacitor and the input capacitor of the conversion unit is passed through the switching element for discharging the capacitor. Completely discharge, then disconnect and open the contactor to disconnect the failed converter, so disconnect the failed converter Without overcurrent flowing through the main contacts of the disconnecting contactor, smooth transition to one side operation.

According to the fifth aspect of the present invention, similarly to the fourth aspect of the present invention, when disconnecting the failed converter, no overcurrent flows to the main contact of the disconnecting contactor, and the operation smoothly shifts to one-sided operation. Also, since the intermediate point of the input filter capacitor and the intermediate point of each input capacitor of the converter are connected, if a short-circuit fault occurs in one converter, the input filter capacitor is also connected from the intermediate point to one side at the same time. Short-circuited,
At the same time, the switching element for discharging the capacitor is turned on to discharge the charge of the capacitor, the voltage of the input filter capacitor is suppressed to one capacitor voltage that is not short-circuited, and the input filter is connected to the input capacitor on the non-short-circuited side of the converter. It is possible to prevent an overvoltage from being applied without a rapid transfer of electric charge from the capacitor.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a control operation of a control unit according to the embodiment.

FIG. 3 is a circuit block diagram according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a control operation of a control unit according to the embodiment.

FIG. 5 is a circuit block diagram according to a third embodiment of the present invention.

FIG. 6 is a circuit block diagram according to a fourth embodiment of the present invention.

FIG. 7 is a circuit block diagram of a conventional example.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Pantograph 2 Contactor 3 Reactor 4 Charging resistor 5A, 5B Converter 5A1, 5A2, 5B1, 5B2 Input capacitor 6 Gate circuit 7 GTO thyristor 8A, 8B Contactor 9A, 9B Load 10 Thyristor 11 Current limiting resistor 12, 12A1, 12A2, 12B1, 12B2 Voltage detector 13 Contactor 15A, 15B, 15E, 15F Separation contactor 15C, 15D, 15G, 15H Contactor coil 16A, 16B, 16C Gate circuit power supply 17A, 17B Control unit 18 Relay 20 Contactor coil 24 Relay 31 Input filter capacitor 32A, 32B Resistor 33A, 33B Capacitor 41, 42 Input filter capacitor

Claims (5)

[Claims] A converter connected in parallel to share a power input system; a gate power supply circuit for a first gate circuit of each of the converters arranged in parallel; and a converter connected to each of the converters arranged in parallel. Detecting a stop of the gate power supply circuit of each of the disconnecting contactors inserted on the input side and the converters arranged in parallel, and opening the disconnecting contactor connected to the converter on the side of the stopped gate power supply circuit; A power conversion device comprising a conversion unit disconnection control unit. A second gate circuit for performing gate control of a switching element for discharging a charge of an input capacitor connected to an input side of the conversion unit when the conversion unit performs a protection operation; and the gate power supply circuit. And a power supply switching unit for connecting the second gate circuit to any one of the above. The conversion unit disconnection control unit detects a stop of the gate power supply circuit connected to the second gate circuit, Opening the disconnecting contactor connected to the converter on the stopped gate power supply circuit side, and switching and connecting the second gate circuit to another healthy gate power supply circuit side by the power supply switching means. The power converter according to claim 1, wherein 3. A second gate circuit for performing gate control of a self-extinguishing type switching element for short-circuiting a charging resistor included in the power supply input system, and the second gate is provided to one of the gate power supply circuits. And a power supply switching unit for connecting a circuit, wherein the conversion unit disconnection control unit detects the stop of the gate power supply circuit connected to the second gate circuit, and causes the power supply switching unit to perform the second switching. 2. The power converter according to claim 1, wherein the gate circuit is switched to and connected to one of other healthy gate power supply circuits. 4. A converter provided in parallel so as to share a power input system; an input filter capacitor provided in the power input system for extending an operation time when power is interrupted; A switching element for discharging the charge of the input capacitor and the charge of the input filter capacitor connected to the input side of the conversion unit when the protection operation is performed; and a switching element inserted into the input side of each of the parallel conversion units. A disconnecting contactor; a contactor coil that opens and closes each of the disconnecting contactors; a circuit connected in parallel with the contactor coil, in which a resistor and a capacitor are connected in series; and a failure of one of the conversion units. To turn on the switching element, and energize the contactor coil to the disconnecting contactor connected to the failed converter. A power conversion device comprising a conversion unit separation control unit for cutting. 5. A converter provided in parallel so as to share a power input system; an input filter capacitor provided in the power input system for extending an operation time when power is interrupted; A switching element for discharging the charge of the input capacitor and the charge of the input filter capacitor connected to the input side of the conversion unit when the protection operation is performed; and a switching element inserted into the input side of each of the parallel conversion units. A first disconnecting contactor; a second contactor inserted between an intermediate point of the input capacitor of each of the converters and an intermediate point of the input filter capacitor.
A contactor coil that opens and closes each of the first and second disconnection contactors; a circuit connected in series with the contactor coil, in which a resistor and a capacitor are connected in series; Detecting any failure of the converter, turning on the switching element, and applying the first and second disconnecting contactors connected to the failed converter to the contactor coil. A power conversion device comprising: a conversion unit disconnection control unit that cuts off energization.