JP2576183Y2 - Self-excited converter - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a self-excited converter.
In particular, the present invention relates to a self-excited converter in which the arrangement of the module and the DC capacitor is changed to reduce the inductance of the connection conductor.

[0002]

2. Description of the Related Art As is well known, as semiconductor devices such as gate turn-off thyristors (hereinafter referred to as GTO) have increased in capacity, large-capacity self-excited converters have been used for linking with a power system. Became.

[0003] An example of a conventional self-excited converter will be described below with reference to the drawings. FIG. 3 is a connection diagram showing a main circuit of a voltage-type multiplex inverter type self-excited converter. In FIG. 3, reference numeral 1 denotes a module in which a GTO 3 and a diode 2 are connected in anti-parallel, and four GTOs 3 connected in anti-parallel to the diode 2 are connected in series.

[0004] Four sets of the GTO modules 1 are further connected in series to form a one-phase two arm, and three sets of these GTO modules 1 are further connected in parallel to form a three-phase bridge circuit, thereby forming an inverter section. Reference numeral 4 denotes a DC capacitor, which is connected in parallel to the inverter unit. The multiplex inverter is configured by connecting a plurality of combinations of the above-described inverter unit and the DC capacitor 4 in parallel.

FIG. 4 is a perspective view showing a state in which each module 1 and the DC capacitor 4 connected to the main circuit connection diagram shown in FIG. 3 are incorporated in a self-excited converter, showing one phase and two arms. . In FIG. 4, 1 is a GTO module,
A circuit in which four GTOs 3 connected in anti-parallel with the diode 2 are connected in series, and associated components such as a snubber circuit (not shown) are configured as one block and housed.

[0006] As shown in FIG. 4, the GTO modules 1 are vertically arranged in four stages with a predetermined gap with the anode side on the right side. Reference numeral 4 denotes a DC capacitor, and three DC capacitors are arranged side by side under the group of GTO modules 1 stacked in four stages, with the terminal side forward. The three DC capacitor 4 is connected in parallel by conductors 6 P, 6 N, to form a single DC capacitor group.

[0007] Of the conductors 15 connecting the four GTO modules 1 arranged in four stages in series, the AC conductor 8 whose lower end is connected to the conductor 15 connecting the middle GTO module 1 is connected to the upper conductor 2. The GTO module unit 1 of the tier is drawn upward from the left side as an AC terminal. The conductors 10P and 10N are connected between the anode terminal 9P and the cathode terminal 9N of the uppermost and lowermost GTO modules 1 and the conductors 6P and 6N connected to the DC capacitor 4.

[0008]

However, in such a self-excited converter in which the GTO module 1 is vertically arranged, two arms of the GTO module 1 are vertically overlapped. The height of the exciter converter is increased. Therefore, the distance between the uppermost GTO module 1 and the DC capacitor 4 increases, and the inductance of the conductor 10P connecting the GTO 3 and the DC capacitor 4 housed inside the GTO module 1 increases.

Therefore, the GTO3 includes the GTO3
At the time of turning off, a large overvoltage generated by the inductance is applied, and there is a possibility of destruction due to this overvoltage. Therefore, in the conventional self-excited converter, in order to prevent such overvoltage destruction at the time of turning off, the circuit voltage is reduced to suppress the voltage applied at the time of turning off the GTO3, or the GTO3 having a high maximum withstand voltage value. In addition, a method of suppressing the voltage applied at the time of turn-off to be equal to or less than the maximum withstand voltage value has been adopted.

[0010] Then, in the conventional self-excited converter configured as described above, the capacity of the GTO 3 cannot be used effectively, which is an obstacle to increasing the capacity of the self-excited converter. Therefore, an object of the present invention is to provide a self-excited converter capable of reducing the inductance between a semiconductor element and a DC capacitor in each module and increasing the capacity of power equipment.

[0011]

According to the present invention, a module in which a single-phase two-arm is divided into a plurality of units is arranged in a plurality of upper and lower stages, and a capacitor connected by a positive-side conductor and a negative-side conductor is arranged in this module group. In the self-commutated converter adjacent to the module group, the polarities of the vertically adjacent modules are opposite to each other, the capacitor is arranged on one side of the module group, and the positive side conductor and the load side conductor are connected between the module group and the capacitor. It is characterized by being installed upright.

[0012]

[Function] Direction of current flowing in vertically adjacent modules
Modules that are vertically adjacent to each other so that
Since the polarity of Yuru are opposite to each other, magnetic flux generated by the current flowing through each module, they are canceled each other
This reduces inductance and reduces DC
Place the sensor near the side of the module.
By placing the positive and negative conductors connected to
The length of the conductor connecting the semiconductor element and the DC capacitor is
It becomes shorter and the inductance becomes smaller.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the self-excited converter according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the self-excited converter of the present invention, showing one phase and two arms, and corresponding to FIG. 4 of the related art. The same parts as those in FIG. 4 are denoted by the same reference numerals.

In FIG. 1, reference numeral 1 denotes a GTO module, in which a circuit in which four GTOs 3 connected in antiparallel to a diode 2 shown in the main circuit connection diagram of FIG. Ancillary parts such as a snubber circuit which is not used are housed in one unit.

The GTO modules 1 are vertically arranged in four stages as in the prior art, but unlike FIG. 4, the polarities of the arms of the vertically adjacent GTO modules 1 are opposite. The GTO modules 1 are stacked in four stages to form the one-phase two-arm shown in the main circuit connection diagram of FIG.

On the right side of these GTO modules 1,
DC capacitors 4a, 4b, 4c are arranged in three stages above and below, and two conductors 6P, 6N are provided on the front surface between the DC capacitors 4a, 4b, 4c and the module 1 on the left side through a predetermined insulating gap. They are arranged vertically and in parallel. In FIG. 1, the left conductor 6P is connected to the negative terminals of the upper and lower DC capacitors 4a, 4b, 4c, and the right conductor 6N is connected to the upper and lower DC capacitors 4a, 4b, 4c.
c is connected to each positive terminal.

The anode terminal 9P of the uppermost left GTO module 1 and the conductor 6P are connected by a conductor 11P, and the cathode terminal 9N of the lowermost GTO module 1 and the conductor 6N are connected by a conductor 11N. The GTO modules 1 are connected in series with each other by conductors 5A, 5B, and 5C. The conductor 5 connecting the central GTO module 1 among the four stages of GTO modules 1
B is connected to the lower end of an AC-side conductor 8, and the upper end of the AC-side conductor 8 is drawn upward as an AC terminal.

In this embodiment, one arm is composed of two GTO modules, and the current flowing through each arm is:
In the uppermost GTO module 1 and the second GTO module 1 from the top, current flows in the same direction in the same arm, and currents also flow in the third and fourth GTO modules 1 in opposite directions. Thus, a current flows in the opposite direction in each stage.

Further, the positive and negative conductors 6P and 6N of the DC capacitor installed on the right side of the GTO module 1 are also arranged in parallel and close to each other, and the conductors 6P and 6N and the uppermost GTO module are arranged.
Joule 1 anode side terminal 9P, bottom GTO module
Conductor 11P connecting the cathode side terminal 9N of the module 1
11N is shorter than the conventional connection conductors 10P and 10N. Therefore, the inductance between the GTO 3 and the DC capacitor 4 can be reduced as compared with the conventional converter, and the peak value of the overvoltage applied to the GTO 3 at the time of turning off can be reduced.

FIG. 2 is a layout diagram showing a case where the one-phase two-arm module group and the capacitor group shown in FIG. 1 are applied to a three-phase bridge circuit. In FIG. 2, conductors 7P and 7N are provided above each module group and each capacitor group.
The conductor 7P is connected to the upper end of a conductor 6P provided vertically and parallel between each module group and each capacitor group, and the conductor 7N is similarly connected between each module group and each capacitor group. Is connected to the upper end of a conductor 6N provided vertically. In the above-described embodiment, the inverter type self-excited converter has been described. However, for example, the present invention can be similarly applied to a PWM conversion circuit that operates in both forward and reverse directions.

[0021]

As described above, according to the present invention, the modules accommodating the one-phase two-arms divided into a plurality are arranged in upper and lower tiers, and a capacitor connected by the positive electrode side conductor and the negative electrode side conductor to this group of modules. In the self-commutated converter adjacent to the module group, the polarities of the vertically adjacent modules are opposite to each other, the capacitor is arranged on one side of the module group, and the positive and negative conductors are connected between the module group and the capacitor. by standing on the inductance because to vanishing out the magnetic flux generated by the current flowing through each module to each other
The DC capacitor has been reduced
Positive and negative conductors placed next to the DC capacitor
By placing them in close proximity to each other,
By reducing the length of the conductor connecting the capacitor, the inductance between the semiconductor element and the capacitor can be reduced, and a self-excited converter that can increase the capacity of the power equipment can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial perspective view showing an embodiment of the self-excited converter of the present invention.

FIG. 2 is a three-phase bridge configuration diagram showing an embodiment of the self-excited converter of the present invention.

FIG. 3 is a main circuit connection diagram of the conventional and self-excited converter of the present invention.

FIG. 4 is a perspective view showing an example of a conventional self-excited converter.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... GTO module, 3 ... Gate turn-off thyristor (GTO), 4a, 4b, 4c ... DC capacitor, 5
A, 5B, 5C, 6N, 6P, 11N, 11P ... conductor, 8 ...
AC side conductor, 9N: cathode side terminal, 9P: anode side terminal.

Claims (1)

(57) [Scope of request for utility model registration] 1. A module in which one-phase two-arms are divided and accommodated in a plurality of units are arranged in upper and lower tiers, and a capacitor connected by a positive conductor and a negative conductor is connected to the module group. In the exciter converter, the polarities of the vertically adjacent modules are set to be opposite to each other, the capacitor is arranged on one side of the module group, and the positive conductor and the load conductor are placed between the module group and the capacitor. Self-excited converter characterized by standing upright.