JPH01174225A - Method and device for automatic control of voltage in consumed power reduction circuit of commercial frequency ac power source - Google Patents

Abstract

PURPOSE:To always stabilize output voltage and reduce consumed power, by switching the output taps of an automatic transformer, based on signal due to voltage fluctuation. CONSTITUTION:When an automatic transformer 2 is provided with output taps 3, and a first output tap is set to come to -5V to input voltage, and following taps are set to come to -7V, -9V, -11V, and -13V, and the voltage value of 90V is set in a detection circuit 5, then, if line voltage is 100V, a third output tap and the secondary side circuit of the automatic transformer 2 are connected to each other. When the line voltage is lowered to 97V, then the detection signal of the detection circuit section 5 is transmitted to a voltage switch controlling section 6, and a contact switching section 7 is worked, and a second output tap is connected to the secondary circuit. On the contrary, when the line voltage is heightened to 103V, then by the same working, a fifth output tap is connected to the secondary side circuit of the automatic transformer 2. In this manner, against the fluctuation of the line voltage, the secondary circuit of the automatic transformer 2 always comes to an almost stabilized voltage value.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to the power consumption of commercial frequency AC power sources (hereinafter referred to as commercial AC power sources) distributed by electric power companies to general households, shops, buildings, factories, etc. The present invention relates to an automatic voltage control method and device in a reduction circuit.

(Conventional technology) Conventionally, the electric power transported from each electric power company through transmission lines was
After the voltage is stepped down to a voltage suitable for distribution at a distribution substation, it is distributed to each consumer, but normally the distributed electricity is left at high voltage for large consumers, and for general households and small consumers. uses a distribution transformer to reduce the voltage and bring it in at low voltage.

Both large-scale consumers, small-scale consumers, and general households use 200V for power and 100V for electric lights.

This 200V to 100V commercial AC power is supplied to each load through a switchboard or a branch circuit formed by a distribution board.An example of this distribution circuit is a power supply for small consumers or general households for electric lights. To explain the case of using 100V according to Fig. 2, the electric wire drawn in in a single-phase three-wire system is connected to the main breaker 21;
Switch (small breaker) 2 for each branch circuit with single-phase two-wire system from
2, and each load is supplied from this small breaker 22.

In this case, the voltage of the commercial AC power supply supplied to each load is 1
00V, and the power consumption of each load is naturally the value obtained by multiplying this power supply voltage and current.

In recent years, energy saving measures have been taken in all kinds of JFs,
This industry is also taking power-saving measures with the aim of reducing power consumption. Specifically, a phase control method is known in which a part of the sine wave alternating current in a commercial commercial current 1lyt is cut to an acceptable extent to reduce the current.

(Problem to be solved by the invention) However, although the phase control method does not affect simple devices such as light bulbs and electric heaters, the current is interrupted even momentarily, so When used in circuits that use lighting equipment such as lamps, interruptions in current affect the operating status of the equipment.

Therefore, the current situation is that it can only be used within a very limited range.

In order to deal with such problems, the present applicant proposed in Patent Application No. 248151 of 1988 that ``an autotransformer is disposed between the main breaker and each load; A safety breaker is installed to protect the autotransformer, an autotransformer is installed between the main breaker and each load, a switch is installed between the autotransformer and each load, and a switch is installed between the main breaker and the autotransformer. The line between the switch and the small breaker is connected to form a bypass circuit, and a switch is interposed in the bypass circuit, and each switch is connected to a current sensor, a temperature sensor,
``Circuit for reducing the power consumption of a commercial frequency AC power source'' characterized by being configured to be automatically controlled by a control circuit consisting of a voltage sensor, an electronic control unit, and a relay, and to step down the voltage of a commercial frequency AC power source by an arbitrary amount. proposed.

However, in the power consumption reduction circuit according to the invention, the voltage output from the tap of the autotransformer was initially set manually, and when a fluctuation occurred in the voltage, the voltage was manually set each time. I have to do it again.

In other words, in buildings with multiple offices or stores, the power consumption of the equipment used varies considerably depending on the season.
During the summer months, when people start using air conditioners such as air conditioners all at once,
The voltage drops due to the heavy load on the circuit itself or the heavy load on nearby power distribution circuits.

If the voltage becomes too low, the equipment used may not operate properly.If we set the power supply voltage supplied at 100V to 90V with an autotransformer, the power supply voltage will change from +00V to 90V. If the voltage drops to 90V, the output voltage of the autotransformer will be 81V unless the output tap of the autotransformer is changed manually, which may have a negative effect on the equipment used.

In order to cope with this, in the prior invention, the output tap of the autotransformer 2 is manually switched in advance when voltage fluctuations are foreseen, but such work is relatively troublesome, and The reality is that it cannot cope with voltage fluctuations.

(Means for Solving the Problems) The present invention addresses these problems, and connects the commercial AC power distributed by the electric power company to the main breaker 1 and the branch circuit small breakers 4, etc. A power distribution circuit is configured to supply power to loads, and the main breaker 1 of the power distribution circuit and each load 4
In this power consumption reduction circuit, an autotransformer 2 is disposed between the autotransformer 2 and an output tap 3 with two or more different voltage settings is provided in the autotransformer 2, and the output tap 3 with two or more different voltage settings is installed. A contact switching section 7 for switching the connection with the secondary circuit of the autotransformer 2 is attached to the output tap 3, a voltage switching control circuit section 6 is connected to the contact switching section 7, and the voltage switching control circuit section 6 is connected to the contact switching section 7. A detection circuit unit 5 for the secondary voltage of the main breaker 1 is connected to the main breaker 1, and the detection circuit unit 5 detects the secondary voltage of the main breaker 1 and sends the detection signal to the voltage switching control circuit unit 6. Based on the transmission signal, the voltage switching control circuit unit operates the contact switching unit 7, switches the connection between the output tap 3 and the secondary circuit of the autotransformer 2, and changes the set output voltage of the autotransformer 2. It is characterized by

(Function) According to the above means, the power supplied to the power distribution circuit passes through the main breaker 1, is stepped down to an appropriate set voltage by the autotransformer 2, and is supplied to each load.

Further, when a fluctuation occurs in the voltage, the detection circuit section 5 detects this and transmits the detection signal to the voltage switching control circuit section 6, and the contact switching section 7 operates based on this transmission signal. The output tap 3 of the autotransformer 2 is switched to maintain a stable voltage at all times.

(Embodiment) An embodiment of the present invention will be described with reference to FIG. 1 of the attached drawings. Reference numeral 1 indicates a main breaker, 2 an autotransformer, 3 . . . output taps provided on the autotransformer 2, respectively.
Different voltages are set, and contact switching units 7 are connected to the output taps 3 . A relay, a magnetic switch, a thyristor, etc. are used for this contact switching section 7.

Reference numeral 5 denotes a voltage detection circuit section using a meter relay, and the detection circuit section 5 is wired to detect the secondary voltage of the main breaker 1.

Reference numeral 6 denotes a voltage switching control circuit section, specifically a program controller, and the voltage switching control circuit section 6 is disposed between the detection circuit section 5 and the contact switching section 7 .

The voltage detected by the detection circuit section 5 is transmitted as a detection signal to the voltage switching control circuit section 6, and the voltage switching control circuit section 6 controls the contact switching sections 7 based on the signal. The output tap 3 is activated by the operation of this contact switching unit 1...
...Switching is performed.

4 is a small breaker for the branch circuit, and main breaker 1
The commercial AC power that has passed through is stepped down to an appropriate voltage by an autotransformer 2, and is supplied to each load via this small breaker 4.

Note that the meter relay used in the detection circuit section 5 may be of a digital type or an analog type. Any circuit may be used as long as it has a means for transmitting information to the section 6.

Further, the voltage switching control circuit section B is not limited to a program controller, and may be constructed by combining a relay, a magnetic switch, a timer, etc.

Therefore, the basic circuit consisting of the main breaker 1, autotransformer 2, and small breaker 4 becomes the power saving circuit X. To explain the power saving effect of this power saving circuit X, for example, toov
If a commercial AC power supply supplied at a voltage of
Power consumption is 90Vx0.9A=81W.

Comparing this with the case where 100V is supplied to the load without using autotransformer 2, when 100V is supplied to the load, the current is 100V + lOOΩ = IA and the power consumption is 100V x lA = 100W, which is a power saving of 19W. be effective.

This is based on the patent application No. 61-248, which was previously proposed by the applicant.
The effect is similar to that of the power saving circuit disclosed in the invention related to No. 151, and although this earlier invention has the problems mentioned above, in the case of the present invention, even if there is a fluctuation in the power supply voltage, The detection circuit section 5 detects this and transmits the detection signal to the voltage switching control circuit section 6, and the contact switching section 7 operates based on this transmission signal to switch the output tap 3 of the autotransformer 2. Always outputs stable voltage.

Next, to explain a specific example, the autotransformer 2 has 5
A set of output taps 3 is provided, of which the first output tap is at -5V with respect to the input voltage, and the second output tap is at -17V.
V, the third output tap is set to -9V, the fourth output tap is set to -11V, the fifth output tap is set to -1+3V, and the detection circuit section 5 is set to a desired voltage value, for example, 90V. The output tap with the voltage closest to the set voltage value, that is, the third output tap when the power supply voltage is 100V, is connected to the secondary side circuit of the autotransformer 2.

If there is a fluctuation in the power supply voltage, for example 100v
If the current voltage drops to 97V, the detection circuit section 5 detects this, transmits this detection signal to the voltage switching control circuit section 6, and the voltage switching control circuit section 6 switches the contact switching section 7.
... is activated and the second output tap is connected to the secondary side circuit of autotransformer 2.

Conversely, if the power supply voltage increases, for example from 100V to 103V, the fifth output tap and the secondary circuit of autotransformer 2 will be connected in the same way. be done.

As described above, although there are some errors, the voltage value in the secondary side circuit of the autotransformer 2 is always approximately stable in response to fluctuations in the power supply voltage.

(Effects of the Invention) The present invention configures a power distribution circuit to supply commercial AC power distributed from a power company to each load via a main breaker 1 and a small branch circuit breaker 4, etc. In a power consumption reduction circuit configured to step down a commercial AC power supply in arbitrary combinations by disposing an autotransformer 2 between the main breaker 1 and each load 4, the autotransformer 2 outputs two or more different voltage settings. A tap 3 is provided, a contact switching section 7 for switching the connection with the secondary circuit of the autotransformer 2 is attached to the output tap 3, and a voltage switching control circuit section 6 is connected to the contact switching section 7. A detection circuit unit 5 for the secondary voltage of the main breaker 1 is connected to the voltage switching control circuit unit 6, and the detection circuit unit 5 detects the secondary voltage of the main breaker 1 and converts the detection signal into a voltage. The voltage switching control circuit 6 operates the contact switching unit 7 based on the transmission signal, switches the connection between the output tap 3 and the secondary circuit of the autotransformer 2, and switches the output tap 3 to the autotransformer 2. Since the set output voltage of autotransformer 2 is changed, if a fluctuation occurs in the power supply voltage regardless of whether it is foreseeable or not, the output voltage of autotransformer 2 will always be stable, reducing power consumption. Reductions can be made even more finely.

In addition, by simply setting a desired voltage value in the detection circuit section 5 at the beginning, tap switching is performed automatically thereafter, which eliminates the need for troublesome work, and provides various excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is a circuit diagram showing a conventional example. Code Table 1 Main breaker 2 Auto transformer 3 Output tap 4 Small breaker 5 Detection circuit section 6 Voltage switching control circuit section 1 Contact switching section X Power saving circuit Figure 1

Claims (2)

[Claims] (1) Commercial frequency AC power distributed by the electric power company,
A power distribution circuit is configured to supply power to each load via the main breaker 1 and small breakers 4 for branch circuits, and an autotransformer 2 is arranged between the main breaker 1 and each load 4 of the distribution circuit. In a power consumption reduction circuit configured to step down a frequency AC power source by an arbitrary amount, a voltage detection circuit section 5 detects the secondary side voltage of the main breaker 1, and transmits the detection signal to a voltage switching control circuit section 6. An automatic voltage control method in a power consumption reduction circuit of a commercial frequency AC power supply, characterized in that the output voltage of the autotransformer 2 is switched based on the transmitted detection signal. (2) Commercial frequency AC power distributed by the electric power company,
A power distribution circuit is configured to supply power to each load via the main breaker 1 and small breakers 4 for branch circuits, and an autotransformer 2 is arranged between the main breaker 1 and each load 4 of the distribution circuit. In the power consumption reduction circuit configured to step down the frequency AC power supply by an arbitrary amount, the autotransformer 2 has two
An output tap 3 with different voltage settings as described above is provided, a contact switching unit 7 for switching the connection with the secondary circuit of the autotransformer 2 is attached to the output tap 3, and the contact switching unit 7 controls voltage switching. Connect the circuit section 6, connect the voltage detection circuit section 5 to the voltage switching control circuit section 6, and switch the connection between the output tap 3 and the secondary side circuit of the autotransformer 2 by the voltage switching control circuit section 6. An automatic voltage control device in a power consumption reduction circuit for a commercial frequency AC power source, characterized in that it is configured as follows.