JPS6013389B2 - Rectifier for large current - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multiphase bridge-connected large current rectifier.

In a high-current AC circuit, it is common practice to place the outgoing conductor and the return conductor as close as possible, so that currents in opposite directions cancel each other's magnetic flux and reduce reactance. .

Therefore, in the conventional three-phase bridge-connected power rectifier, as shown in Fig. 1, each phase DC winding (secondary winding) U, V, W of the three-phase transformer 1 is The side walls of the transformer tank 1 are arranged side by side in a state where they are penetrated therethrough, and are led out side by side to the outside of the transformer tank via the positive and negative terminals u, v; v, w; w, u of each phase; A three-phase transformer 1 and a three-phase rectifier 2, which is assembled separately from the three-phase transformer 1 and housed in a box, are connected in a triangular or star shape using a connecting conductor 3, and the rectifier 2 Each phase rectifying arm u′,
, u'2;v', , v'2; W, , w'2 via the common bus 4 of each phase. In addition, 5. in the figure.
6 is a positive and negative polarity DC bus, P, N' is a positive and negative polarity DC terminal, and the AC winding (primary winding) of the transformer 1 is omitted. However, in such a large current rectifier, the DC windings U, V, and W of each phase of the transformer 1 are connected to three-phase wires outside the transformer tank.
As the required amount of conductor between them increases, the dimensions between the transformer 1 and the rectifier 2 increase, increasing the footprint area of the device.

Furthermore, since the connection of the rectifier 2 is performed within a limited installation area, when a large number of the above-mentioned connection conductors 3 are arranged, the influence of the magnetic field generated by the current flowing through the connection conductors 3 will cause the connection between each parallel rectifier element. Another drawback was that the shared currents became unbalanced, resulting in poor efficiency.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, reduce the required amount of connection conductors between the transformer and the rectifier, and reduce the installation area of the device, as well as make the overall configuration compact. An object of the present invention is to provide a large current rectifier that can improve efficiency.

In order to achieve this object, the present invention connects each phase DC winding in a multi-phase connection within a transformer tank, and also attaches a box containing a multi-phase rectifier to one side wall of the transformer tank, and penetrates the one side wall. and a positive polarity DC terminal for each phase and a negative polarity DC terminal for each phase are provided adjacent to each phase terminal on both sides of each phase terminal, and the DC winding is multiphase connected to one end of each phase terminal. , connect one end of each phase common bus of the multiphase rectifier to the terminal of each phase terminal, and connect each phase common bus arranged in parallel on both sides of the respective phase common bus that is branched and connected to the terminal of each phase common bus. A phase rectifier arm is connected to one end of the positive polarity DC terminal of each phase and the negative polarity DC terminal of each phase, respectively, and the ends of the positive polarity DC terminal of each phase and the negative polarity DC terminal of each phase are respectively placed in the transformer tank. Connect these positive polarity DC busses and negative polarity DC busses to the positive polarity DC terminal and negative polarity DC terminal provided on the side wall of the transformer tank, respectively. An embodiment of the present invention will be described below with reference to FIG.

In FIG. 2, the same reference numerals as in FIG. 1 indicate the same or equivalent components. The DC windings U, V, and W of each phase of the three-phase transformer 1 are triangularly connected in the transformer tank, and the phase terminals U, V, and W are connected to each other through the side wall of the transformer tank. It is connected. On the other hand, one end of each phase common bus 4 of the three-phase rectifier 2 is connected to each phase terminal u, v, and w, and the other end is branched, and each phase common bus 4 is arranged parallel to and close to the common bus 4. Two sets of rectifying arms u′, , u′2: v′, , v
'2: w', , w'2; and these rectifier arms are connected to each phase terminal u on the side wall of the transformer tank.
, v, w and close to them, positive and negative polarity DC terminals of each phase are provided penetrating the side walls u, , &;
v., v2: connected to W., W2, respectively.

In addition, each phase positive and negative polarity DC terminal u, ri; v,, v
2;w,, the terminals are connected to the positive and negative DC terminals P provided in the transformer tank by the positive and negative DC terminals 5 and 6, which are provided through the side wall of the transformer tank. , N.

In the large current rectifier constructed horizontally as described above, the current flowing through the transformer phase terminals u, v, and w flows from the transformer turtle side to the rectifier 2 side, as shown by the solid arrows. (during the first half cycle), each phase positive polarity DC terminal u,,
A current flows from the rectifier 2 side to the transformer 1 side in v, Lw, and a current flows in each phase terminal u, v, w of the transformer from the rectifier 2 side to the transformer 1 side as shown by the broken line arrow. (during the latter half cycle), current flows from the transformer 1 side to the rectifier 2 side in each phase negative polarity DC terminal 吃, v2, w2.

That is, during one cycle, the terminals u and u, or u2, v and v, or v2, w and w, or w2, which are juxtaposed close to each other on the side wall of the transformer tank, always have the same size. By the way,
And since currents flow in opposite directions, the magnetic fluxes caused by the currents flowing through these terminals cancel each other out,
The induced current induced in the side wall portion of the transformer tank through which these terminals pass can be reduced, and overheating of this portion can be prevented.

Moreover, since the DC windings U, V, and W of each phase of the transformer can be connected within the transformer tank, transformer 1 and rectifier 2
The dimensions between them can be reduced, the required amount of connection conductors between them can be reduced, and the area under the foot of the rectifier can be reduced, so that the overall configuration can be made smaller.

Moreover, since the influence of the magnetic field due to the current of the connecting conductor on each rectifying element of the rectifier 2 can be reduced, the shared current between the parallel rectifying elements can be balanced, and an efficient rectifying device can be obtained. In the above embodiment, the DC windings U, V, and W of each phase of the transformer are connected in a triangular manner, but the present invention can similarly be applied to a case in which they are connected in a star shape as shown in FIG. can.

As explained above, according to the present invention, the DC windings of each phase of the transformer can be connected without multiphase connection outside the transformer tank.
Terminals that always carry current in opposite directions can be juxtaposed in close proximity to the transformer tank, reducing the dimensions between the transformer and the rectifier, reducing the amount of connecting conductors required, and simplifying the installation of the rectifier. The area can be reduced, and the overall configuration can be made smaller.

Furthermore, it is also possible to reduce the influence of the magnetic field due to the current in the connecting conductor on each rectifier element of the rectifier, balance the shared current between the parallel rectifier elements, and improve the efficiency.

[Brief explanation of drawings]

Figure 1 is a wiring diagram of a conventional rectifier for general use, Figure 2
The figure is a wiring diagram of a large current rectifier according to one embodiment of the invention, and FIG. 3 is a wiring diagram of a large current rectifier according to another embodiment of the invention. 1... Three-phase transformer, 2... Three-phase rectifier, 4
...... Rectifier common bus, 5, 6... Positive and negative polarity DC bus, U, V, W... Transformer DC winding, u, v, w... Transformer phase terminals , u・, u2, V・・
V2・w,... each phase positive and negative polarity DC terminal,
u',, u'2, v',, v'2, w',, w'2...
Each phase rectifier arm, P, N...Positive and negative polarity DC terminals. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A high-current transformer equipped with a polyphase transformer and a polyphase rectifier assembled separately from the polyphase transformer, with each phase DC winding and each phase rectifier arm of the polyphase rectifier connected to each other. In the rectifier, the DC windings of each phase are multiphase connected in a transformer tank, a box for accommodating the multiphase rectifier is attached to one side wall of the transformer tank, and a box is inserted through the one side wall of the transformer tank. A positive polarity DC terminal for each phase and a negative polarity DC terminal for each phase are provided in close proximity to each phase terminal on both sides of each phase terminal, and the polyphase-connected DC winding is connected to one end of each phase terminal. Then, one end of each phase common bus of the multiphase rectifier is connected to the other end of each phase terminal, and each phase common bus is connected in parallel to the other end of each phase common bus, and each phase common bus is connected in parallel to the other end of each phase common bus. A phase rectifier arm is connected to one end of each of the positive polarity DC terminal of each phase and the negative polarity DC terminal of each phase,
The other ends of each phase positive polarity DC terminal and each phase negative polarity DC terminal are respectively connected to a positive polarity DC bus and a negative polarity DC bus provided in the transformer tank, and these positive polarity DC bus and negative polarity DC bus are connected to each other. A rectifying device for large current, characterized in that the busses are connected to a positive polarity DC terminal and a negative polarity DC terminal respectively provided on the other side wall of a transformer tank.