JP2008301570A - Voltage variation suppressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress variation in amplitude of an AC voltage to be applied to a load device easily. <P>SOLUTION: The voltage variation suppressor is interposed between an AC power supply and a load device and suppresses variation in amplitude of an AC voltage outputted from the AC power supply prior to voltage application to the load device. The device comprises a voltage regulating section having a voltage limiter circuit composed of a plurality of Zener diodes connected in series with their forward directions opposite to each other and outputting an AC voltage obtained by applying the AC voltage to the voltage limiter circuit, a voltage input section for applying the AC voltage outputted from the AC power supply to the voltage regulating section, and a voltage output section for applying the AC voltage outputted from the voltage regulating section to the load device. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a voltage fluctuation suppressing device that suppresses fluctuations in the amplitude of an alternating voltage.

  In recent years, technology has advanced and it has become possible to receive extremely high-quality power supply from electric power companies. However, when there is a facility that consumes a large amount of current, such as an electric furnace or electric welder, the voltage of the power supplied to the consumer fluctuates, causing flickering of lighting equipment and television receivers. May occur.

Such voltage fluctuations are evaluated with an index of ΔV ₁₀ in the power line and are suppressed to a reference value or less, but flickering of a lighting fixture or the like may be felt depending on various conditions.

As a technique for suppressing such voltage fluctuation, for example, a technique for suppressing flickering of a fluorescent lamp due to voltage fluctuation in a train is known (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 06-217401

  By the way, flickering of the lighting fixture can be suppressed to some extent by using, for example, an inverter lighting type lighting fixture. However, in this case, it is necessary to replace the lighting fixture with an inverter system. In addition, since fluctuations in the voltage applied to the lighting fixture are not suppressed in the first place, there may be a case where a sufficient flicker suppression effect cannot be obtained depending on conditions such as the amount of voltage fluctuation and the fluctuation cycle.

  In addition, the AC power supplied from the AC power source, such as CVCF (Constant-Voltage Constant-Frequency), is once converted to DC power, and the DC power is converted back to AC power to achieve stable amplitude. There is also a method of supplying an alternating voltage having a frequency to the load device. However, in this case, it is necessary to install large and expensive equipment.

  For this reason, there is a need for a technique that can easily suppress fluctuations in the amplitude of the AC voltage.

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a voltage fluctuation suppressing device that can easily suppress fluctuations in the amplitude of an AC voltage.

  In order to solve the above-described problems, the present invention provides a voltage fluctuation suppression that is interposed between an AC power supply and a load device, and that suppresses fluctuations in amplitude of an AC voltage output from the AC power supply and is supplied to the load device. The device has a voltage limiter circuit in which a plurality of zener diodes are connected in series so that each forward direction is reverse, and an AC voltage obtained by applying an AC voltage to the voltage limiter circuit is provided. A voltage adjusting unit for outputting, a voltage input unit for applying the AC voltage output from the AC power source to the voltage adjusting unit, and a voltage output unit for applying the AC voltage output from the voltage adjusting unit to the load device And a voltage fluctuation suppressing device comprising:

  By such an aspect, it is possible to easily suppress fluctuations in the amplitude of the AC voltage applied to the load device. That is, when the AC voltage output from the AC power source is applied to the voltage adjustment unit by the voltage input unit, the sum of the breakdown voltage and the forward voltage of each Zener diode constituting the voltage limiter circuit in one direction (hereinafter, Since the voltage exceeding the limit voltage is also cut, no voltage higher than the limit voltage is applied to the load device. For this reason, even when the amplitude of the alternating voltage output from the alternating current power supply is fluctuating, the fluctuation can be suppressed and applied to the load device. Further, as in the case of using CVCF or the like, there is no need for useless control for once converting all of the AC power supplied from the AC power source to DC power, and the AC voltage applied to the load device is very simple. It is possible to suppress fluctuations in the amplitude.

In addition, the voltage adjusting unit includes a single-turn transformer in which first to fourth taps are provided on a coil, and the first tap and the second tap include one of the voltage limiter circuits. A terminal and the other terminal are connected, the AC power supply is connected between the first tap and the third tap, and the load device is connected between the first tap and the fourth tap. You may make it connect.
By such an aspect, even if the upper limit value of the amplitude of the AC voltage output from the AC power source, the limit voltage, and the upper limit value of the amplitude of the AC voltage applied to the load device do not match, the load device It is possible to easily suppress fluctuations in the amplitude of the applied AC voltage.

Further, the position of each tap on the coil includes the number of windings of the coil from the first tap to the third tap and the number of windings of the coil from the first tap to the second tap. And the number of windings of the coil from the first tap to the fourth tap, the upper limit value of the amplitude of the AC voltage output from the AC power supply, and each of the voltage limiter circuits The Zener diode may be set so as to correspond to a ratio between the sum of the breakdown voltage and the forward voltage of the Zener diode in one direction and the upper limit value of the amplitude of the AC voltage applied to the load device.
By such an aspect, the voltage fluctuation is optimally suppressed according to the ratio of the upper limit value of the amplitude of the AC voltage output from the AC power supply, the limit voltage, and the upper limit value of the amplitude of the AC voltage applied to the load device. The device can be designed.

The voltage output unit may include a low-pass filter, and an AC voltage output from the voltage adjustment unit may be applied to the load device via the low-pass filter.
By such an aspect, a high frequency component can be removed from the alternating voltage applied to a load apparatus, and it becomes possible to prevent malfunction etc. of a load apparatus.

The load device may be a lighting fixture.
According to such an aspect, it is possible to prevent the lighting device from flickering without replacing the lighting device with an inverter system.

  In addition, the problems disclosed by the present application and the solutions thereof will be clarified by the column of the best mode for carrying out the invention and the drawings.

  Variations in the amplitude of the AC voltage can be easily suppressed.

FIG. 1 shows an embodiment of an electric circuit 1000 using the voltage fluctuation suppressing device according to the present invention. In the present embodiment, the flicker reducing device 100 corresponds to a voltage fluctuation suppressing device.
Flicker reduction apparatus 100 is interposed between AC power supply 800 and load apparatus 700 and suppresses fluctuations in the amplitude of the AC voltage output from AC power supply 800 and supplies it to load apparatus 700.

  The AC power supply 800 is, for example, a commercial power supply rated at 100 volts, and outputs an AC voltage having a frequency of 50 Hz or 60 Hz. The AC power supply 800 may be configured by a generator that generates AC power, or may be configured by a transformer such as a pole transformer that converts high voltage power into low voltage power.

  In addition, AC power supplied from a power plant by an electric power company has little fluctuation in amplitude, frequency, etc. and is of high quality, but has a facility that consumes a large current such as an electric furnace or an electric welder in the neighborhood. When there is a factory or the like, the amplitude of the AC voltage may fluctuate as indicated by point (A) in FIG. Although the fluctuation period varies, it is often about several hertz to several tens of hertz. In addition, the fluctuation range of the amplitude is suppressed to a specified value or less in the power line, but it may be about 1 to 2 volts on the customer premises.

  The load device 700 is a device that consumes AC power. The load device 700 is configured by a lighting device such as a fluorescent lamp. The load device 700 may be configured by an electrical product such as a television receiver or a radio receiver. When the amplitude of the AC voltage input to these load devices 700 fluctuates, the screen of a fluorescent lamp or television flickers. In general, it is known that the flickering feeling is large when the fluctuation cycle of the amplitude of the AC voltage is about 10 hertz.

The flicker reduction apparatus 100 includes a voltage input unit 120, a voltage adjustment unit 110, and a voltage output unit 130.
The voltage input unit 120 applies the AC voltage output from the AC power supply 800 to the voltage adjustment unit 110. In the example illustrated in FIG. 1, the voltage input unit 120 includes a resistance unit 121. The resistance unit 121 limits the current flowing through the electric circuit 1000 so that it does not become excessive. The resistance unit 121 is configured by, for example, a coil or a resistance element.

  The voltage adjustment unit 110 includes a voltage limiter circuit 111 in which a plurality of Zener diodes 112 are connected in series so that their forward directions are opposite to each other, and the AC voltage output from the AC power supply 800 is converted into a voltage limiter circuit. The alternating voltage obtained by applying to 111 is output.

  The voltage limiter circuit 111 is configured by connecting a plurality of Zener diodes 112 in series so that their forward directions are opposite to each other, and the sum of the breakdown voltage and the forward voltage of each Zener diode 112 in one direction. When a voltage exceeding (limit voltage) is applied, the excess voltage is cut and output. Each zener diode may be connected in any direction as long as the forward direction is connected in the reverse direction. For example, as shown in FIG. 1, the anodes of the two Zener diodes 112 may be connected in the direction in which the anodes are connected, or may be connected in the direction in which the cathodes are connected. When two or more Zener diodes 112 are connected in series, the Zener diodes 112 having different directions may be connected in any order.

  By providing the voltage adjusting unit 110, as shown in FIG. 1, even when the amplitude of the AC voltage output from the AC power supply 800 is fluctuating (the voltage at the point (A)), the voltage adjusting unit 110. Since the voltage exceeding the voltage determined according to the limit voltage is cut and output (the voltage at the point (B)), the amplitude fluctuation can be suppressed.

  In this case, although the voltage between both terminals of the voltage limiter circuit 111 is different from the voltage between both terminals of the AC power supply 800, the difference in the voltage can be absorbed by providing the resistor 121. In this case, a current determined by the difference between the voltage between both terminals of the voltage limiter circuit 111 and the voltage between both terminals of the AC power supply 800 and the resistance value of the resistance section 121 flows through the resistance section 121.

  The voltage output unit 130 applies the AC voltage output from the voltage adjustment unit 110 to the load device 700. In the flicker reduction apparatus 100 according to the present embodiment, the voltage output unit 130 includes a low-pass filter 131. The voltage output unit 130 applies the AC voltage output from the voltage adjustment unit 110 to the load device 700 via the low-pass filter 131.

Thereby, it becomes possible to remove the high frequency component contained in the alternating voltage output from the voltage adjustment part 110, and to supply to the load apparatus 700 (waveform of the (C) point of FIG. 1). More specifically, since the AC voltage output from the voltage adjustment unit 110 has a sine wave with a flat peak, the AC voltage is a harmonic mainly including the third harmonic. Harmonics can be cut. In this case, the low-pass filter 131 may set the cutoff to about the second harmonic so as to pass the fundamental wave and block the third harmonic.
Note that the low-pass filter 131 according to the present embodiment can be configured as an LC low-pass filter, as shown in FIG. 4 as an example.
Of course, the voltage output unit 130 may not include the low-pass filter 131. In this case, the voltage output unit 130 directly applies the AC voltage output from the voltage adjustment unit 110 to the load device 700.

In the flicker reduction apparatus 100 shown in FIG. 1, the voltage limiter circuit 111 includes two Zener diodes 112, but the voltage limiter circuit 111 may be configured using more Zener diodes 112. . This is shown in FIG.
In the flicker reducing apparatus 110 shown in FIG. 2, the voltage limiter circuit 111 is configured using ten Zener diodes 112. In this way, the voltage limiter circuit 111 can be configured using the Zener diode 112 having a low breakdown voltage and a small allowable loss.

  For example, the breakdown voltage of the commercially available Zener diode 112 is about 50 volts at the maximum, but when the AC power supply 800 is a commercial power supply with a rating of 100 volts, the desired limit voltage is about 130 volts to 140 volts. Further, the allowable loss of the commercially available Zener diode 112 is about 1 watt continuously, and about several hundred watts to 1 kilowatt even intermittently.

  Therefore, by increasing the number of Zener diodes 112 constituting the voltage limiter circuit 111, a desired limit voltage can be obtained and the loss of each Zener diode 112 can be kept within an allowable value.

  For example, the case where the AC voltage output from the AC power supply 800 is rated 100 volts (peak 141 volts) and the load of the load device 700 is 100 watts (power factor 1) will be specifically described. The internal impedance of power supply device 800 and the resistance value of resistance unit 121 are combined to be 1 ohm.

  In this case, the current flowing through the load device 700 is 1 ampere (peak 1.4 amperes), and the load impedance is 100 ohms.

  When the voltage limiter circuit 111 is composed of ten Zener diodes 112 as in the flicker reducing apparatus 100 shown in FIG. 2, the Zener diode 112 having a breakdown voltage of 27 volts (minimum 24 volts, maximum 30 volts). By using this, the limit voltage can be set to 135 volts in 5 series.

  Also, at the peak of the AC voltage output from the AC power supply 800, the current flowing through the 1 ohm resistor is 6 amperes (because the voltage drop is 6 volts (141 volts-135 volts)). Among them, since 1.4 amperes flows to the load device 700, a current of 4.6 amperes flows through the voltage limiter circuit 111. Since it is 3.3 amperes in terms of effective value, the power consumption in the voltage limiter circuit 111 is 330 watts.

  However, the flow is only when the AC voltage output from the AC power supply 800 is 135 volts or more, and is about 25% of the total period. For this reason, the power consumption in the voltage limiter circuit 111 is 83 watts if the time average is taken.

  If 83 watts are shared by the five Zener diodes 112, then 17 watts per unit. If the Zener diode 112 having such a standard is used, the voltage limiter circuit 111 can be easily configured. For example, it is possible to use a power zener diode that is distributed for surge absorption.

  The breakdown voltage of the Zener diode 112 has a variation of about ± 10%. Therefore, when the number of Zener diodes 112 constituting the voltage limiter circuit 111 is small, a desired limit voltage is obtained in order to obtain a desired limit voltage. Zener diode 112 having a breakdown voltage must be screened. However, when the number of Zener diodes 112 constituting the voltage limiter circuit 111 is large, it is possible to determine the limit voltage more easily and accurately by considering the combination of the Zener diodes 112.

The voltage adjustment unit 110 according to the present embodiment can also be realized by a configuration as shown in FIG.
That is, the voltage adjustment unit 110 includes a single-turn transformer 113 in which first to fourth taps are provided on a coil, and one of the voltage limiter circuits 111 is included in the first tap and the second tap. The terminal and the other terminal are connected, the AC power supply 800 is connected between the first tap and the third tap, and the load device 700 is connected between the first tap and the fourth tap.
As a result, even if the upper limit value of the AC voltage output from the AC power supply 800, the limit voltage, and the upper limit value of the AC voltage applied to the load device 700 do not match, the AC voltage applied to the load device 700. It is possible to easily suppress fluctuations in voltage amplitude.

For example, since the minimum voltage of the power line is about 95 volts as an effective value (about 135 volts at the peak), the limit voltage needs to be set around 135 volts in order to suppress the voltage fluctuation at this time as well. There is. However, the breakdown voltage of the Zener diode 112 used in the voltage limiter circuit 111 is not necessarily 135 volts.
On the other hand, when the amplitude of the AC voltage output from the AC power supply 800 is cut, the voltage applied to the load device 700 is lowered, and therefore, the standard of the load device 700 may not be met.

  Therefore, by configuring the voltage adjustment unit 110 as shown in FIG. 3, the upper limit value of the AC voltage output from the AC power supply 800, the limit voltage, the upper limit value of the AC voltage applied to the load device 700, Even if they do not match, it is possible to easily suppress fluctuations in the amplitude of the AC voltage applied to the load device 700.

  Here, the position of each tap on the coil of the autotransformer 113 includes the number of windings of the coil from the first tap to the third tap and the winding of the coil from the first tap to the second tap. The ratio of the number of wires and the number of windings of the coil from the first tap to the fourth tap is such that the upper limit value of the amplitude of the AC voltage output from the AC power supply 800, the limit voltage, and the load device 700 It may be set so as to correspond to the ratio of the upper limit of the amplitude of the AC voltage to be applied.

  For example, when a zener diode 112 having a breakdown voltage of 50 volts is used, the AC voltage output from the AC power supply 800 is clipped at 135 volts and supplied to the load device 700 rated at 100 volts at a rating (141 volts at the peak). Includes the number of turns of the coil from the first tap to the third tap, the number of turns of the coil from the first tap to the second tap, and the number of turns from the first tap to the fourth tap. A tap is provided at each position where the ratio of the number of turns of the coil is 135: 50: 141.

  In this case, the autotransformer 113 provided with a plurality of taps in advance is prepared, and an appropriate tap is appropriately selected according to the power supply voltage, the characteristics of the Zener diode to be used, and the characteristics of the load device 700. Also good. As a result, even if the power supply voltage, the characteristics of the Zener diode, the characteristics of the load device 700, and the like differ, it is possible to cope with this by simply manufacturing one type of autotransformer 113. For this reason, it is possible to manufacture the autotransformer 113 at a low cost, and it is possible to realize a cheaper flicker reduction device 100.

  The flicker reducing apparatus 100 according to the present embodiment has been described above. However, according to the flicker reducing apparatus 100, it is possible to easily suppress fluctuations in the amplitude of the AC voltage applied to the load apparatus 700.

  The above embodiment is for facilitating understanding of the present invention, and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

It is a figure which shows the structural example of the electric circuit containing the flicker reduction apparatus which concerns on this Embodiment. It is a figure which shows the structural example of the electric circuit containing the flicker reduction apparatus which concerns on this Embodiment. It is a figure which shows the structural example of the electric circuit containing the flicker reduction apparatus which concerns on this Embodiment. It is a figure which shows the structural example of the low-pass filter which concerns on this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Flicker reduction apparatus 110 Voltage adjustment part 111 Voltage limiter circuit 112 Zener diode 113 Autotransformer 120 Voltage input part 121 Resistance part 130 Voltage output part 131 Low pass filter 700 Load apparatus 800 AC power supply 1000 Electric circuit

Claims (5)

A voltage fluctuation suppression device that is interposed between an AC power supply and a load device, suppresses fluctuations in the amplitude of the AC voltage output from the AC power supply, and supplies the fluctuation to the load device,
A voltage adjustment unit having a voltage limiter circuit formed by connecting a plurality of zener diodes in series so that the forward directions thereof are opposite to each other, and outputting an AC voltage obtained by applying an AC voltage to the voltage limiter circuit When,
A voltage input unit for applying an AC voltage output from the AC power source to the voltage adjustment unit;
A voltage output unit for applying an AC voltage output from the voltage adjustment unit to the load device;
A voltage fluctuation suppressing device comprising: The voltage fluctuation suppressing device according to claim 1,
The voltage adjustment unit has a single-winding transformer in which first to fourth taps are provided on a coil,
One terminal and the other terminal of the voltage limiter circuit are connected to the first tap and the second tap,
The AC power supply is connected between the first tap and the third tap,
The voltage fluctuation suppressing device, wherein the load device is connected between the first tap and the fourth tap. The voltage fluctuation suppressing device according to claim 2,
The position of each tap on the coil is
The number of windings of the coil from the first tap to the third tap, the number of windings of the coil from the first tap to the second tap, and the fourth tap to the fourth tap The ratio of the number of windings of the coil up to the tap is the upper limit of the amplitude of the AC voltage output from the AC power supply, and the one direction of the breakdown voltage and forward voltage of each Zener diode constituting the voltage limiter circuit A voltage fluctuation suppressing device, which is set to correspond to a ratio between a sum of minutes and an upper limit value of an amplitude of an alternating voltage applied to the load device. The voltage fluctuation suppressing device according to claim 1,
The voltage output unit includes a low-pass filter, and applies an AC voltage output from the voltage adjustment unit to the load device through the low-pass filter. The voltage fluctuation suppressing device according to claim 1,
The load device is a lighting fixture.

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