JPS58222320A - Automatic voltage adjusting device - Google Patents

Abstract

PURPOSE:To attain a titled device with small capacity, by applying an output of a semiconductor switch circuit to a primary winding of a series transformer at the normal state of the semiconductor switch circuit and applying an output of a regulating transformer to the primary winding at the abnormal state of the said switch circuit. CONSTITUTION:The switching circuit 17 is connected to an output of the semiconductor switch circuit 8 through a terminal 17a at the normal operation and the output of the semiconductor switch circuit 8 is applied to the primary winding of the series transformer 6. If the failure takes place in the semiconductor switch circuit 8, the switching circuit 17 is changed over quickly and connected to the secondary winding of the 2nd regulating transformer. As a result, an output voltage is compensated independently of the failure of the semiconductor switch circuit 8 by adding or subtracting a voltage induced in the series transformer with the secondary voltage of the 2nd regulating transformer 16 to or from an input voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic voltage regulator that adjusts the voltage supplied to the load within a fixed voltage range, for example, when the load is connected to a system in which the AC input voltage fluctuates.

Conventionally, a device of this type is shown in Fig. 1.

In Figure 1, (1) is a distribution transformer installed in the distribution system, (2) is an automatic voltage regulator, and (8) is a load supplied with a predetermined voltage. is a series transformer (8) in which a secondary winding is inserted between the input end (4) and the output end (6), and whose secondary voltage is added to or subtracted from the total AC input voltage, and a series transformer (8) that inputs the AC voltage. Through the end (4) the receiver is connected to a regulating transformer (γ) which transforms and obtains the voltage applied to the primary winding of said series transformer (6), and by the secondary voltage of said regulating transformer (γ). A semiconductor switch circuit (11) that controls the direction and magnitude of application of
8). t7tm semiconductor switch circuit (
8) is a thyristor switch (9), αQ, consisting of an anti-parallel circuit of two thyristors as shown in FIG.

When the thyristor switches (9) and (12) are turned on, the positive polarity of the series transformer (6) is established, and the thyristor switches α0. When olJ is turned on, the secondary voltage of the regulating transformer (γ) is applied to the negative polarity of the series transformer (6).

Next, the operation of the automatic voltage regulator having the above configuration will be described with reference to FIG. 6, which shows the case where the configuration is used for single phase.

What is the operation of the automatic voltage regulator shown in Figure 17g5? This can be explained as the operation of the tap changer shown in FIG. The thyristor switch α in Fig. 3 is turned on (tl-ON).

(9) and ofJ? When set to oF'y, or thyristor switch (9) and (b) are turned on, shout and (b)g are turned off.
In this case, no voltage is generated in the secondary winding of the single-row transformer (6), and the input voltage V is output as the output voltage V. This means that the tap in Figure 4) is 0.
This corresponds to the case of being in the 0 state. In addition, when thyristor switches (9) and (2) tONK, (to) and (b) are turned off, the secondary voltage vIS of the regulating transformer (γ) is applied in the direction of increasing the input voltage vX, Output voltage V, is V,
=Vyu+net.

becomes. Note that n is the turns ratio of the series transformer (6).

This case corresponds to the case where the tap (b) in FIG. 4 is in the +1 state. Set t1 thyristor switch y f
al ト＜１υko NKs ＜9＞ト（Ia'fro
The secondary voltage v3 of the yy'KT s regulating transformer (γ) is applied in the direction of lowering the input voltage V, and the output voltage VS
Ha s v * = v nee n - ■.

becomes. This case corresponds to the case where the tap (to) in FIG. 4 is in the -1 state.

In this process, the thyristor switches (9) to (2) shown in Fig.
) can be turned on and off in combination, the tap (b) in Figure 4 can be raised or lowered, and when the input voltage V is smaller than the predetermined output voltage V, When the input voltage V is higher than the predetermined output voltage V1, the tap (B) is lowered to adjust the voltage, and the output voltage V can be compensated. Note that the above explanation is about a single-phase automatic voltage regulator.

A similar explanation can be given to a multiphase automatic voltage regulator.

Conventional automatic voltage regulators are configured as described above, so that they can vary within a symmetrical range of positive and negative (hereinafter referred to as "symmetrical variation") by, for example, ±5% with respect to a predetermined output voltage. For a certain input voltage, an automatic voltage regulator with an adjustment range of ±5% can be used, but even with the same 10% fluctuation, for a given output voltage there is a range of 110% to 0, which is asymmetrically positive and negative. For input voltages that may fluctuate (hereinafter referred to as "asymmetric fluctuations"), an automatic voltage regulator with an adjustment range of +10 t should be used, i.e.
The adjustment transformers, semiconductor switch circuits, etc. of each component require larger capacities than those for symmetrical fluctuations, which has the disadvantage of making the equipment expensive. In order to eliminate this drawback, the conventional method was to step up or step down the power supply voltage using a distribution transformer and pass the asymmetrically fluctuating input voltage to an automatic voltage regulator as a symmetrically fluctuating input voltage. In this method, an inappropriate voltage may be supplied to the load when the semiconductor switch circuit is abnormal. In other words, even if the semiconductor switch circuit is abnormal, it is necessary to continue supplying voltage to the load. For example, although the input voltage must be lowered by 10 minutes to supply the output voltage, the circuit However, there is a drawback that there are cases where the output voltage is increased by 10% due to an abnormality, and the load is burnt out.

The present invention has been made to eliminate the drawbacks of the conventional conventional device, and when an abnormality occurs in the semiconductor switch circuit, the converted magnetic voltage t-
At the same time, when the semiconductor switch circuit is normal, the output of the semiconductor switch circuit is 1 of the t-series transformer.
An automatic voltage regulator that is a small-capacity device that can supply the load with an output voltage that is regulated to a predetermined voltage during normal conditions and compensated for a certain amount during abnormal conditions by applying it to the next winding. The purpose is to provide.

Hereinafter, an embodiment of the invention made to achieve the purpose of coughing will be described with reference to FIG. In Figure 5, %CL, 3)
is a regulator 11 between the input terminal (4) and the series transformer (6).
1 □ 1 voltage transformer (installed in parallel with γ) and ratio adjusting □ transformer (in the description of this embodiment, the adjusting transformer (7)'t f@ 1 adjusting transformer, adjusting transformer α 0 ■ adjusting (called a transformer).

The secondary winding of the second regulating transformer) is connected to the switching circuit (b).
is connected to one terminal (17'b) of the. Further, the other terminal (17a) of the switching circuit aη is connected to the semiconductor switch circuit (
On the output side of 8), the common terminal is connected to the primary winding of the series transformer (6) and the above-mentioned terminals (17a) and (171:
+) is made depending on whether the semiconductor switch circuit (8) is normal or abnormal.

Next, the operation of the above illustrated embodiment will be explained. 6 During normal operation, the switching circuit Q'r) is connected to the output side of the semiconductor switch circuit (8) through the terminal (17a)';i.

It operates in the same way as a conventional automatic voltage regulator.

On the other hand, if an abnormality occurs in the semiconductor switch circuit (8), the switching circuit Uη is quickly switched and connected to the secondary winding of the second regulating transformer α6). As a result.

The series transformer (6) adds or subtracts the voltage induced by the secondary voltage of the second regulating transformer α6) to the input voltage V, and the semiconductor 1'1:□Putsch circuit (8) Regardless of the abnormality.

Output voltage can be compensated.

The following will explain using the total compensation side values of the output voltage from the second regulating transformer (R) when the semiconductor switch circuit (8) is abnormal. For example, consider a case where the input voltage of an automatic voltage regulator varies asymmetrically by 0 to 20% compared to a predetermined voltage. In this case, if the distribution transformer (1) has a tap.

The input voltage to the automatic voltage adjustment device is always kept 10 degrees higher around this tap, and the input voltage fluctuation of the automatic voltage adjustment device is set to ±10%. Suppose that an abnormality occurs in the semiconductor switch circuit (8) at this time.

Switching circuit αyt-to the connection terminal (+ to 17) with the second regulating transformer αG), this second regulating transformer α6)
A secondary voltage t″ of is applied to the primary winding of the series transformer (6),
Here, all adjustments of -10- are performed. As a result, the voltage that is increased due to the tap change of the distribution transformer (1) is canceled out. This is 9. Supply of the increased voltage to the load (8), which may occur due to an abnormality in the semiconductor switch circuit (8), or completely block the supply of the increased voltage to the load (8) during the entire history of the voltage. Completely prevents burnout, etc.

Also, even if the distribution transformer (1) does not have a tap.

If the voltage of the load (8) can be set, such as in a welding machine, the output voltage of the automatic voltage regulator may be lowered by setting the voltage of the load (8) to a 1.0% lower value in advance. Also 1
Assuming that 0% lower is acceptable, the automatic voltage regulator can be operated by regarding the input voltage fluctuation as a symmetrical fluctuation of ±10%. Even in this case, if an abnormality occurs in the semiconductor switch circuit (8), the switching circuit (1! When operated, the load (8) can be supplied with a certain compensation voltage.

Furthermore, FIG. 6 shows another embodiment of the present invention.

In Fig. 6, (to) is a tapped regulating transformer that can achieve the functions of the first regulating transformer (7) and the second regulating transformer (16) in Fig. 5 in one unit, and is a switching transformer. When the circuit Qη is in contact with the tap, it has the same function as the second regulating transformer (16) described above, and the switching circuit qη has the same function as the semiconductor switch circuit (16).
8), it achieves the same function as the above-mentioned first regulating transformer (η), that is.

In the event of an abnormality in the semiconductor switch circuit (8), the series transformer (6)
) is applied directly to the primary winding of the semiconductor switch circuit (8), and when the semiconductor switch circuit (8) is normal, the switch circuit (8)
It outputs the converted voltage. Other points in FIG. 6 are the same as in FIG. 5.

Incidentally, the automatic voltage regulator 1- in the above-mentioned friend inventions,
It goes without saying that the present invention can be applied to either a single phase or S3 phase, and it is clear that a semiconductor switch such as a thyristor switch may be used for the switching circuit (5). Furthermore, in the illustrated embodiment of each of the above-mentioned inventions, the switching circuit tJ71? Although it is provided on both sides of the series transformer (6), it is clear that the same effect can be achieved even if it is provided only on one side.

As described above, according to the automatic voltage regulator of the present invention, when the semiconductor switch circuit is abnormal, the converted voltage of the regulator transformer is directly applied to the primary winding of the series transformer, and when the semiconductor switch circuit is normal, the converted voltage of the regulator transformer is directly applied to the primary winding of the series transformer. Since the output of this semiconductor switch circuit is applied to the primary winding of the series transformer, the output voltage, which is regulated to a specified voltage during normal operation, can be adjusted to a specified voltage during normal operation using a small-capacity device. This has the advantage that a compensated output voltage can be supplied to the load.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a conventional automatic voltage regulator, FIG. 2 is a circuit diagram showing an example of the semiconductor switch circuit of the conventional device shown in FIG. 1, and FIG. 3 is a circuit diagram of the conventional device shown in FIG. 4 is an auxiliary diagram for explaining the operation of the conventional device shown in FIG. 3, FIG. 5 is a complete circuit diagram of an automatic voltage regulator according to an embodiment of the present invention, and FIG. 6 is a circuit diagram showing an example of application to a phase. FIG. 2 is a circuit diagram showing an automatic voltage regulator according to another embodiment of the present invention. (1): Wiring transformer (2): Load (6): Series transformer (γ), α6), (to)): Adjustment transformer (8): Semiconductor switch circuit μη: Switching circuit Note that in the diagram The same reference numerals indicate the same or equivalent parts. Agent Shin Kuzuno − Yama:. Figure 1 Figure 3 Figure 4 Dear Commissioner of the Patent Office 1. Display of the incident Patent application No. 57-105802 No. 2
, Name of the invention Automatic voltage regulator 3, Person making the amendment Representative Hitoshi Katayama Part 6, Contents of the amendment (11 Changed the description ``overflow transformer (6)'' on page 3, line 16 of the specification to ``series (2) The statement “20%” on page 9, line 3 of the specification should be amended to “pressure instigator (6).”
-20%”. that's all

Claims (2)

[Claims] (1) If-secondary winding is inserted between the input terminal receiving the input voltage from the AC power supply and the output terminal connected to the load. A series transformer that supplies a predetermined voltage to the load by adding or subtracting the voltage generated in the secondary winding to the total input voltage, and a series transformer that transforms the input voltage and supplies it to the primary winding of the series transformer. and a regulating transformer to obtain the applied voltage. In an automatic voltage regulator comprising a semiconductor switch circuit that controls all switching directions of voltage application to the primary winding of the series transformer and controls the applied voltage value, when the semiconductor switch circuit is abnormal, the An abnormality adjustment transformer is provided in parallel with all of the above adjustment transformers to transform the input voltage of the semiconductor switch circuit and directly supply the voltage to the primary winding of the series transformer. Output terminal metal, the other side, the above semiconductor switch circuit -
An automatic voltage regulator comprising: a switching circuit for connecting the output end of the abnormality adjustment transformer to the primary winding of the series transformer in the event of an abnormality. (2) A secondary winding is inserted between the input terminal that receives the input voltage from the AC power source and the output terminal that is connected to the load. a series transformer that supplies a predetermined voltage to a load by adding or subtracting the voltage generated in the secondary winding to the input voltage; and a series transformer that transforms the input voltage to supply a predetermined voltage to the primary winding of the series transformer. An automatic voltage regulator comprising a regulating transformer that obtains an applied voltage, and a semiconductor switch circuit that controls switching of all directions of voltage application to the primary winding of the series transformer and controls the applied voltage value, An abnormality tap that directly applies voltage to the primary winding of the series transformer when the semiconductor switch circuit is abnormal is provided on the secondary winding of the regulating transformer, and when the semiconductor switch circuit is normal, the semiconductor switch An automatic voltage regulator characterized in that it is provided with a switching circuit that switches the output end of the circuit to connect the output end of the circuit to the primary winding of the series transformer when the semiconductor switch circuit is abnormal. .