JP2016015817A - Power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve compaction and cost reduction of a power supply device, by increasing the impedance between output windings thereby omitting an interphase reactor, in a power supply device having a thyristor rectifier in an AC-DC conversion unit.SOLUTION: In a power supply device including a multi-winding input transformer TFhaving more than one output windings S, T of the same phase and transforming an AC voltage, and a plurality of thyristor rectifiers 1c, 1d connected in parallel and performing AC-DC conversion of each output from the output windings of the input transformer TF, the input transformer TFconnects the output windings, respectively and directly, with the AC input terminals of respective thyristor rectifiers 1c, 1d, winds the more than one output windings S, T of the same phase at different positions of an iron core 3 in the longitudinal direction. A magnetic gap g1 is formed in the vertical direction between the output windings S, T with the core 3 as the center, and the plurality of thyristor rectifiers connect the same poles of respective DC output terminals directly.

Description

  The present invention relates to a power supply device to which two or more thyristor rectifiers connected in parallel to an AC-DC converter are applied.

  In general, in the case of a power supply device that performs rectification by providing two or more rectifiers connected in parallel on the output side of a three-winding transformer, the phase of the output voltage is shifted in order to equalize the pulsating component in the rectified DC voltage. It is necessary to increase the number of phases. Further, in order to reduce the harmonic current flowing out to the input side AC power supply of the three-winding transformer, the output side secondary winding and tertiary winding are connected in three windings as Δ-Y connection or Y-Δ connection. A phase difference is provided in the output voltage of the line transformer (for example, Patent Document 1: Paragraph [0004], FIG. 6).

  In the case of the diode rectifier type power supply device shown in FIG. 3, it is necessary to provide an interphase reactor L in order to prevent a cross current between the diode rectifiers 1a and 1b.

  If the currents output from the two diode rectifiers 1a and 1b are balanced and have the same value, the magnetomotive forces generated by the currents output from the two diode rectifiers 1a and 1b are opposite to each other. Magnetic flux is not generated and the inductance value can be regarded as zero.

  When the currents output from the two diode rectifiers 1a and 1b have different unbalanced values, the difference component of the magnetomotive force is generated in the coil of the interphase reactor L connected to the output side of the diode rectifiers 1a and 1b. Magnetic flux is generated. The magnetic flux due to the magnetomotive force difference component acts as an inductance, and the inductance component suppresses an increase in the current imbalance between the diode rectifiers 1a and 1b, thereby preventing a cross current.

  In the case of the thyristor rectifier type power supply device shown in FIG. 4, it is possible to balance control the output current by the thyristor rectifiers 1c and 1d by controlling the balance of the thyristor elements. However, since the thyristor rectifiers 1c and 1d control the energization rate according to the control angle of the thyristor element, the ripple of the current waveform is large, and an interphase reactor L for preventing cross current is also required.

JP 2008-178180 A JP-A-5-30661

In the case of the thyristor rectifier type power supply device shown in FIG. 4, it is possible to balance the output current of the thyristor rectifier by the balance control. However, as shown _in FIG. 5, the conventional input transformer TFin uses a secondary winding S and a cross winding with a tertiary winding T in each phase on the transformer output side. , The tertiary winding T is in close contact, and the mutual inductance between the windings is reduced. For this reason, the impedance of the secondary winding S and the tertiary winding T on the transformer output side is reduced, and an interphase reactor L needs to be provided in order to prevent cross current. As a result, a wiring space between the thyristor rectifiers 1c and 1d and the interphase reactor L and an installation space for the interphase reactor L are required, and there is a problem that the power supply device is increased in size and cost.

  As described above, in the power supply apparatus having a thyristor rectifier in the AC-DC converter, the impedance between the output windings of the secondary winding S and the tertiary winding T is increased in each phase of the input transformer. Therefore, it becomes a problem to reduce the size and cost of the power supply device by omitting the interphase reactor.

  The present invention has been devised in view of the above-described conventional problems, and one aspect thereof includes a multi-winding input transformer that has two or more output windings in the same phase and transforms an alternating voltage. A plurality of parallel-connected thyristor rectifiers that convert each output of the output winding of the input transformer into AC-DC, respectively, wherein the input transformer Connect directly to the AC input terminal of the thyristor rectifier, wind two or more output windings of the same phase around each other at different positions in the vertical direction around the iron core, and vertically between the output windings around the iron core. A magnetic gap is formed, and the plurality of thyristor rectifiers are characterized in that the same polarity of the respective DC output terminals are directly connected to each other for output.

  The magnetic gap between the output windings is a distance that prevents a cross flow of the output current of the thyristor rectifier.

  According to the present invention, in the power supply device having a plurality of thyristor rectifiers connected in parallel to the AC-DC converter, the interphase reactor is omitted by increasing the impedance between the output windings in each phase of the input transformer, The power supply device can be reduced in size and cost.

The block diagram which shows the power supply device in embodiment. The schematic sectional drawing which shows the input transformer in embodiment. The block diagram which shows the power supply apparatus of the conventional diode rectifier system. The block diagram which shows the power supply device of the conventional thyristor rectifier system. The schematic sectional drawing which shows the input transformer in the past.

  Hereinafter, an embodiment of a power supply device according to the present invention will be described with reference to FIGS.

[Embodiment]
FIG. 1 is a single-line connection diagram illustrating the power supply device according to the first embodiment. As shown in FIG. 1, the power supply device in the present embodiment 1 includes an AC power source Vs, an input transformer TF _in, thyristor rectifier 1c, and 1d, an inverter Inv, and an output transformer TF _out, the . A load 2 is connected to the output side of the output transformer TF _out .

FIG. 2 is a schematic cross-sectional view showing the input transformer TFin _in an arbitrary phase in the present embodiment. 2, the input transformer TF _in is transformer third winding has a secondary winding S of the primary winding P and the output side of the input side, the tertiary windings T, the . The input transformer TF _in receives the AC voltage output from the AC power source Vs through the primary winding P and transforms it, and the secondary winding S with the voltage phase shifted to suppress the pulsating component of the rectified DC voltage. And the tertiary winding T. The configuration of the input transformer TF _in, will be described later.

Thyristor rectifier 1c, 1d rectifies the output voltage of the secondary winding S and tertiary winding T of the input transformer TF _in each. The inverter Inv connects the DC output voltage rectified by the thyristor rectifiers 1c and 1d in parallel and directly connects to the DC input terminal of the inverter Inv for DC-AC conversion. The output transformer TF _out transforms the AC voltage output from the inverter Inv and supplies it to the load 2.

As shown in FIG. 2, the input transformer TF _in in the present embodiment is configured such that the winding method of the secondary winding S and the tertiary winding T wound around the iron core 3 is vertically arranged.

  Specifically, the secondary winding S and the tertiary winding T are wound around different positions in the vertical direction around the iron core 3. Further, a magnetic gap g1 is formed in the vertical direction of the iron core 3 between the secondary winding S and the tertiary winding T.

  Further, a primary winding P is wound around the iron core 3 around the outer periphery of the secondary winding S and the tertiary winding T. The primary winding P is divided and arranged in the vertical direction of the iron core 3 on the outer peripheral side of the secondary winding S and the outer peripheral side of the tertiary winding T. In addition, a magnetic gap g2 is formed between the primary winding P and the secondary winding S in the radial direction, and a magnetic gap is formed between the primary winding P and the tertiary winding T in the radial direction. g3 is formed. Further, the primary windings P arranged in a divided manner are connected in parallel.

In the power supply device having the above structure and the input transformer TF _in the thyristor rectifier 1c, 1d, the secondary winding S of the input transformer TF _in even the ripple current waveform is large, magnetic between tertiary winding T The mutual inductance increases due to the gap g1. The impedance between the secondary winding S and the tertiary winding T can be increased by this mutual inductance, and the cross current between the thyristor rectifiers 1c and 1d can be suppressed by this impedance. As a result, the interphase reactor L can be omitted.

  Thereby, the wiring space and installation space of the interphase reactor L become unnecessary.

  In addition, since the interphase reactor L can be omitted, the cost of the apparatus can be reduced.

Input transformer TF _in the present embodiment, the volume and weight as compared with the conventional input transformer TF _in are equivalent, amount corresponding to the omitted interphase reactor L, the wiring space and installation space of the power supply is unnecessary Can be downsized.

  Although the present invention has been described in detail only for the specific examples described above, it is obvious to those skilled in the art that various changes and modifications are possible within the scope of the technical idea of the present invention. Such variations and modifications are naturally within the scope of the claims.

For example, although described input transformer TF _in the third winding in the embodiment, is applicable if the input transformer TF _in the third winding or more multi-winding.

Further, in the embodiment has been described for the input transformer TF _in the three winding in any phase, the input transformer TF _in the single phase even number of phases greater than three-phase or three-phase can be applied .

Further, the embodiment has described the power supply device of particular configuration, the input transformer TF _in having a multi-winding, the AC output of the input transformer TF _in - thyristors to DC rectifier 1c, and 1d, the Any power supply device can be applied.

P ... primary winding S ... secondary winding T ... tertiary winding g1~g3 ... gap 1c, 1d ... thyristor rectifier 3 ... core L ... interphase reactor TF _in ... input transformer

Claims (2)

A multi-winding input transformer having two or more output windings in the same phase and transforming an AC voltage;
A plurality of parallel-connected thyristor rectifiers that convert each output of the output winding of the input transformer into AC-DC, respectively;
A power supply device comprising:
The input transformer is
Connect the output winding directly to the AC input terminal of each thyristor rectifier, and wind two or more output windings of the same phase around each other at different positions in the vertical direction. A magnetic gap is formed in the center in the vertical direction,
The plurality of thyristor rectifiers output power by directly connecting the same polarity of each DC output terminal.   2. The power supply apparatus according to claim 1, wherein the magnetic gap between the output windings is a distance that prevents a lateral flow of the output current of the thyristor rectifier.

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