WO2020194373A1 - Ferroresonance suppression device and voltage transformer provided with same - Google Patents

Ferroresonance suppression device and voltage transformer provided with same Download PDF

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Publication number
WO2020194373A1
WO2020194373A1 PCT/JP2019/012065 JP2019012065W WO2020194373A1 WO 2020194373 A1 WO2020194373 A1 WO 2020194373A1 JP 2019012065 W JP2019012065 W JP 2019012065W WO 2020194373 A1 WO2020194373 A1 WO 2020194373A1
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voltage
iron
iron core
transformer
resistor
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PCT/JP2019/012065
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French (fr)
Japanese (ja)
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角田　孝典
大輔 澁谷
芳樹 川渕
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日新電機株式会社
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Priority to PCT/JP2019/012065 priority Critical patent/WO2020194373A1/en
Publication of WO2020194373A1 publication Critical patent/WO2020194373A1/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/04—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers

Definitions

  • the present invention relates to an iron resonance suppression device for suppressing an iron resonance phenomenon in a voltage transformer for measuring voltage in a transmission line or an electric power facility, and a voltage transformer provided therewith.
  • Power equipment with an iron core has an exciting inductance L.
  • the circuit system is a circuit in which the capacitance C coexists, the iron core constituting the exciting inductance L due to the transient phenomenon when the circuit is opened and connected (when the circuit breaker or the like is opened and closed). Is temporarily magnetically saturated, energy is transferred between the circuits, and the vibration is sustained, which may cause abnormal noise, burning due to overheating, dielectric breakdown, and the like. This phenomenon is known as the iron resonance phenomenon.
  • the iron resonance phenomenon is an electrical disturbance phenomenon starting from the saturation phenomenon of the iron core.
  • Non-Patent Document 1 As shown in FIG. 4, the iron resonance phenomenon has a: fundamental overvoltage mode, b: subharmonic mode, and c: quasi-periodic mode. It is disclosed that it is classified into four patterns of periodic mode) and d: Chaotech mode (Chaotic mode).
  • the fundamental wave overvoltage mode is a vibration mode in which the amplitude of the fundamental wave becomes large and harmonics such as third and fifth orders are superimposed.
  • the fractional tuning mode is a vibration mode in which a large fractional tuning (1 / n tuning) vibration is added to the fundamental wave.
  • the quasi-periodic mode is a vibration mode having a difference frequency between frequencies that are integral multiples of each of the two frequencies.
  • the chaotic mode is a vibration mode in which it is difficult to specify the period and the behavior is chaotic.
  • Non-Patent Document 2 discloses a circuit configuration using a saturable reactor. Specifically, with reference to FIG. 5, a saturable reactor 902 connected in series and a resistor 904 having a low resistance value are connected in parallel to the secondary winding of a transformer 900 such as a voltage transformer. When the iron resonance phenomenon occurs, the saturable reactor 902 is saturated by the generated voltage, and the generated current is passed through the resistor 904 to absorb the resonance energy. As a result, the iron resonance phenomenon is suppressed.
  • Patent Document 1 discloses measures for the fractional wave adjustment mode. That is, a circuit for detecting the overvoltage of 1/3, 1/5, and fundamental waves peculiar to iron resonance is provided on the secondary side of the instrument transformer, and the iron resonance phenomenon is detected and assisted by this circuit. It drives a relay and absorbs resonance energy with a low resistance load.
  • Non-Patent Document 2 the saturable reactor may not be sufficiently saturated depending on the situation, and the iron resonance phenomenon may continue. If the iron resonance phenomenon continues, the equipment may burn out.
  • a complicated circuit using a semiconductor IC is used, and its control power also needs to be supplied from the outside, resulting in a high cost and a large-sized device.
  • the present invention adopts a method using a saturable reactor, can detect the magnetic saturation phenomenon of the iron core representing the iron resonance phenomenon itself more reliably than before, and can suppress the iron resonance phenomenon quickly and efficiently. It is an object of the present invention to provide a resonance suppression device and a voltage modulator equipped with the resonance suppression device.
  • the iron resonance suppression device is an iron resonance suppression device for suppressing an iron resonance phenomenon in an iron core and a transformer having a primary winding and a secondary winding wound around the iron core.
  • a saturable reactor in which one terminal is connected to one terminal in the secondary winding, and a first terminal connected between the other terminal in the saturable reactor and the other terminal in the secondary winding.
  • the occurrence of iron core saturation of the transformer is detected from the DC voltage generator that rectifies and smoothes the voltage between both terminals of the resistor and the first resistor and outputs it as a DC voltage, and the DC voltage output from the DC voltage generator.
  • It includes an iron core saturation detecting unit and a short-circuiting portion that short-circuits both terminals of the secondary winding via a second resistor in response to the detection of the occurrence of iron core saturation by the iron core saturation detecting unit.
  • the magnetic saturation phenomenon of the iron core which represents the iron resonance phenomenon itself generated in a voltage transformer or the like having a transformer, can be detected more reliably than before, and the iron resonance phenomenon can be suppressed quickly and efficiently.
  • the impedance of the saturable reactor is designed to be smaller than the impedance of the first resistor when the iron core of the transformer is saturated. As a result, the iron resonance phenomenon can be quickly suppressed.
  • the impedance of the saturable reactor is designed to be smaller than the impedance of the first resistor when the transformer core saturation approaches.
  • the energy can be consumed by the second resistance at the stage before the iron resonance phenomenon occurs, that is, at the stage when the sign of the iron resonance phenomenon occurs, and the occurrence of the iron resonance phenomenon can be suppressed.
  • the short circuit is a relay
  • the contacts of the relay and the second resistor are connected in series and connected between both terminals of the secondary winding
  • the core saturation detector controls the contacts of the relay.
  • a DC voltage output from the DC voltage generator is applied to both terminals of the coil and the switching element connected in series, including a switching element connected in series to the coil to be connected and a constant voltage element to control the switching element.
  • the constant voltage element turns on the switching element, and when the switching element is turned on, a current flows through the coil and the contacts are turned on.
  • the iron resonance phenomenon can be suppressed by turning on the relay and consuming the resonance energy by the second resistor without separately providing a power source for driving the relay. Therefore, a small iron resonance suppression device can be realized.
  • the voltage transformer according to the second aspect of the present invention includes an iron core, a transformer having a primary winding and a secondary winding wound around the iron core, and the above-mentioned iron resonance suppression device, and suppresses iron resonance.
  • the device suppresses the iron resonance phenomenon in the transformer.
  • the magnetic saturation phenomenon of the iron core which represents the iron resonance phenomenon itself generated in the voltage transformer, can be detected more reliably than before, and the iron resonance phenomenon can be suppressed quickly and efficiently.
  • the magnetic saturation phenomenon of the iron core which represents the iron resonance phenomenon itself generated in the voltage transformer or the like, can be detected more reliably than before, and the iron resonance phenomenon can be suppressed quickly and efficiently. That is, by using the saturable reactor as a sensor, the iron resonance phenomenon can be detected even in a saturated state in which the saturable reactor is insufficient, and the iron resonance phenomenon can be quickly suppressed.
  • the iron resonance suppression device can be realized as a relatively small-scale circuit, not as a circuit through which a large current flows. Therefore, it is possible to incorporate an iron resonance suppression device into an existing voltage transformer or the like.
  • the voltage transformer includes a transformer 200 and an iron resonance suppression unit 100.
  • the transformer 200 is a transformer that constitutes the main body of the voltage transformer, and outputs an output signal OUT from the secondary winding.
  • the iron resonance suppression unit 100 includes a saturable reactor 102, a rectifying smoothing unit 104, an active element 106, a level detection unit 108, a relay unit 110, and resistors R1 and R2.
  • the saturable reactor 102 and the resistor R1 are connected in series.
  • the saturable reactor 102 and the resistor R1 connected in series are connected in parallel to the secondary winding of the transformer 200. As a result, the AC voltage generated in the secondary winding is shared by the saturable reactor 102 and the resistor R1.
  • the saturable reactor 102 has, for example, an iron core having a steep magnetic saturation characteristic, and is designed by simulating the saturation characteristic of a transformer as described above. That is, in the normal state where the transformer is not saturated, it is not saturated and has a large impedance. On the other hand, when the transformer is saturated or approaches saturation, the saturable reactor 102 is saturated and the impedance decreases sharply. When the saturable reactor 102 is saturated, its impedance is preferably sufficiently smaller than the impedance of the resistor R1. For the design of the saturable reactor, a method of designing the saturation magnetic flux density from the secondary voltage waveform based on the saturation characteristics of the transformer is used.
  • Both terminals of the resistor R1 are connected to the input terminals of the rectifying smoothing unit 104. That is, of the two input terminals of the rectifying smoothing unit 104, the first input terminal in1 is connected to one terminal of the resistor R1, and the second input terminal in2 is connected to the other terminal of the resistor R1.
  • the potential of one terminal of the resistor R1 is V1
  • the potential of the other terminal is V2.
  • the rectifying and smoothing unit 104 rectifies and smoothes the AC voltage (V1-V2) between both terminals of the input resistor R1, and direct current is applied between the two output terminals (first output terminal out1 and second output terminal out2). Generate a voltage (V3-V4).
  • the potential of the first output terminal out1 is V3, and the potential of the second output terminal out2 is V4.
  • the potential V4 of the second output terminal out2 is a reference potential of the DC voltage output from the rectifying smoothing unit 104.
  • the rectifying and smoothing unit 104 can be configured by a known rectifying circuit and smoothing circuit.
  • a full-wave rectifier circuit (for example, a bridge circuit with four diodes) is preferably used as the rectifier circuit, but a half-wave rectifier circuit may be used.
  • the smoothing circuit can be realized, for example, by providing a capacitor (smoothing capacitor) between the output terminals of the rectifier circuit.
  • the smoothing capacitor is for smoothing the voltage (pulsating current) rectified by the rectifier circuit and generating a constant DC voltage.
  • the active element 106 is connected between the first output terminal out1 of the rectifying smoothing unit 104 and the relay unit 110.
  • the active element 106 has a function as a switching element that is controlled by a signal input to the gate to short-circuit or open the first output terminal out1 of the rectifying smoothing unit 104 and the relay unit 110.
  • a level detection unit 108 is connected to the gate of the active element 106.
  • the level detection unit 108 has a function of maintaining the voltage between both terminals at a constant value when the voltage between both terminals exceeds a certain value. That is, when the potential V3 of the first output terminal out1 of the rectifying / smoothing unit 104 becomes equal to or higher than a predetermined value, the level detecting unit 108 is connected to the potential of the first output terminal out1 of the rectifying / smoothing unit 104 and the gate of the active element 106. The difference (voltage) from the potential V5 of the terminal is maintained at a constant value. If this constant value is set to a value equal to or higher than the gate voltage at which the active element 106 is turned on, the active element 106 is turned on.
  • the relay unit 110 is, for example, a known relay, and a coil for turning on the internal contact is connected between the active element 106 and the second output terminal out2 of the rectifying smoothing unit 104.
  • One terminal of the internal contact is connected to the resistor R2 and the other terminal is grounded.
  • the terminal not connected to the relay portion 110 of the resistor R2 is connected to the output line of the transformer 200.
  • the resistor R2 is a resistor having a small resistance value, and is for absorbing resonance energy due to the iron resonance phenomenon.
  • the iron resonance phenomenon occurs when the iron core of the transformer of the transformer is saturated.
  • the iron resonance suppression unit 100 configured in this way takes measures by using a waveform in which this phenomenon appears in the secondary voltage.
  • the iron resonance suppression unit 100 operates as follows.
  • the saturable reactor 102 In the normal state where the iron resonance phenomenon does not occur, the saturable reactor 102 is not saturated and has a large impedance, and the voltage generated in the secondary winding of the transformer 200 is almost the saturable reactor 102.
  • the voltage between both terminals of the resistor R1 is a small value. Therefore, the input voltage (alternating current) of the rectifying and smoothing unit 104 is small, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104 is small, the voltage between both terminals of the level detecting unit 108 is small, and the active element 106 is It remains off. Therefore, no current flows through the coil inside the relay unit 110, the internal contacts remain off, and no current flows through the resistor R2.
  • the input voltage (alternating current) of the rectifying and smoothing unit 104 increases, and the DC voltage (V3-V4) output from the rectifying and smoothing unit 104 also increases.
  • the voltage between both terminals of the level detection unit 108 becomes a constant value (the voltage that turns on the active element 106 is also large), the active element 106 is turned on, and the first output terminal out1 and the second output terminal out2 of the rectifying smoothing unit 104 are turned on. Is connected to the coil of the relay unit 110, and a current flows through the coil.
  • the iron resonance suppression unit 100 returns to the normal state. That is, the saturable reactor 102 is no longer saturated, its impedance becomes large, the voltage generated in the secondary winding of the transformer 200 is almost shared by the saturable reactor 102, and the voltage between both terminals of the resistor R1 becomes small. .. That is, the input voltage (alternating current) of the rectifying and smoothing unit 104 becomes small, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104, and the voltage between both terminals of the level detecting unit 108 become small, and the active element 106 Turns off. Therefore, the internal contact of the relay unit 110 is turned off, and no current flows through the resistor R2.
  • the iron resonance phenomenon can be suppressed by using the saturable reactor 102 as a sensor for detecting the magnetic saturation phenomenon of the iron core of the transformer, which represents the essence of the iron resonance phenomenon itself.
  • the iron resonance suppression unit 100 can be realized as a relatively small-scale circuit, not as a circuit through which a large current flows. Further, since the rectifying smoothing unit 104, the active element 106, and the level detecting unit 108 are used as a control power source for driving the relay unit 110 when the iron resonance phenomenon occurs, the power source for driving the relay unit 110 is used. It is not necessary to separately provide it or to supply the voltage for driving the relay unit 110 from an external power source. Therefore, the iron resonance suppression unit 100 can be manufactured inexpensively and compactly, and the iron resonance suppression unit 100 can be incorporated in an existing voltage transformer.
  • the voltage transformer according to this modification includes a transformer 200 and an iron resonance suppression unit 130.
  • the transformer 200 is a transformer that constitutes the main body of the voltage transformer, and outputs an output signal OUT from the secondary winding.
  • the iron resonance suppression unit 130 includes the same components as the iron resonance suppression unit 100 shown in FIG. That is, the iron resonance suppression unit 130 includes a saturable reactor 102, a rectifying smoothing unit 104, an active element 106, a level detection unit 108, a relay unit 110, and resistors R1 and R2.
  • the iron resonance suppression unit 130 differs from the iron resonance suppression unit 100 only in the connection relationship between the active element 106 and its peripheral elements, and the function of each element is the same as that of the iron resonance suppression unit 100. Therefore, in the following, the duplicate description will not be repeated, and the points different from the iron resonance suppression unit 100 will be mainly described.
  • the active element 106 is connected between the second output terminal out2 of the rectifying smoothing unit 104 and the relay unit 110 (specifically, one end of the internal coil).
  • the active element 106 is controlled by a signal input to the gate to short-circuit or open the second output terminal out2 of the rectifying smoothing unit 104 and the relay unit 110.
  • the first output terminal out1 of the rectifying and smoothing unit 104 is directly connected to the relay unit 110 (the other end of the internal coil).
  • the iron resonance suppression unit 130 configured in this way operates in the same manner as the iron resonance suppression unit 100 of FIG. That is, in the normal state where the iron resonance phenomenon does not occur, the saturable reactor 102 is not saturated and has a large impedance, and the voltage generated in the secondary winding of the transformer 200 is almost saturable. It is shared by the reactor 102, and the voltage between both terminals of the resistor R1 is a small value.
  • the input voltage (alternating current) of the rectifying and smoothing unit 104 is small, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104 and the voltage between both terminals of the level detection unit 108 are small, and the active element 106 and the relay unit The internal contacts of 110 remain off and no current flows through resistor R2.
  • the saturable reactor 102 When the iron resonance phenomenon occurs, the saturable reactor 102 is saturated and its impedance sharply decreases. As a result, the voltage generated in the secondary winding of the transformer 200 is almost shared by the resistor R1, and the voltage between both terminals of the resistor R1 rapidly increases. Therefore, the input voltage (alternating current) of the rectifying and smoothing unit 104 increases, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104, and the voltage between both terminals of the level detection unit 108 increase, and the active element 106 Is turned on, and the first output terminal out1 and the second output terminal out2 of the rectifying smoothing unit 104 are connected to the coil of the relay unit 110, and a current flows through the coil.
  • the current flowing through the primary winding of the transformer 200 returns to the normal level, and the iron resonance suppression unit 130 returns to the normal state.
  • the iron resonance suppression unit 130 As described above, in the iron resonance suppression unit 130 as well, as described above, by using the saturable reactor 102 as a sensor for detecting the magnetic saturation phenomenon of the iron core, the saturable reactor 102 is in an insufficient saturated state. Even so, the iron resonance phenomenon can be suppressed. Further, it is not necessary to separately provide a power source for driving the relay unit 110 or to supply a voltage for driving the relay unit 110 from an external power source, and the iron resonance suppression unit 130 can be formed inexpensively and compactly. It is also possible to incorporate the iron resonance suppression unit 130 into an existing voltage transformer.
  • FIG. 3 A more specific circuit configuration is shown as an example. An embodiment corresponding to FIG. 2 is shown in FIG. With reference to FIG. 3, the rectifying smoothing section 104 is composed of a full-wave rectifying circuit 114 and a capacitor C1. The active element 106 and the level detection unit 108 are composed of a transistor 116 and a Zener diode 118, respectively.
  • one output terminal (terminal of potential V3) of the full-wave rectifier circuit 114 is connected to the base terminal of the transistor 116 via a Zener diode 118 and a resistor R5.
  • the resistor R5 is a resistor for limiting the base current of the transistor 116.
  • One output terminal (terminal of potential V3) of the full-wave rectifier circuit 114 is also connected to the relay unit 110 (internal coil) via a resistor R6.
  • the resistor R6 is for adjusting the current flowing through the coil inside the relay unit 110 and the transistor 116 when the transistor 116 is turned on.
  • the iron resonance suppression unit configured as shown in FIG. 3 can suppress the iron resonance phenomenon.
  • an iron resonance phenomenon occurs and the voltage between both terminals of the resistor R1, that is, the input voltage (alternating current) of the full-wave rectifier circuit 114 suddenly increases, the voltage (V3-V4) output from the full-wave rectifier circuit 114. Will increase.
  • the potential of the cathode of the Zener diode 118 to which one terminal of the resistor R5 is connected becomes the DC voltage generated by smoothing the voltage output from the full-wave rectifier circuit 114 by the capacitor C1 and becomes the gate of the transistor 116.
  • a base current that turns on the transistor 116 flows through the resistor R5.
  • the active element 106 is composed of N-channel transistors
  • the present invention is not limited to this.
  • N-channel MOSFETs may be used.
  • FETs other than MOSFETs may be used.
  • the magnetic saturation phenomenon of the iron core which represents the iron resonance phenomenon itself generated in a voltage transformer or the like, can be detected, and the iron resonance phenomenon can be suppressed quickly and efficiently.

Abstract

This ferroresonance suppression device is for suppressing a ferroresonance phenomenon in a transformer having an iron core and a primary coil and a secondary coil wound around the iron core. The ferroresonance suppression device includes: a saturable reactor having one terminal connected to one terminal of a secondary coil; a first resistance connected between the other terminal of the saturable reactor and the other terminal of the secondary coil; a DC voltage generation unit that outputs a DC voltage by rectifying and smoothing a voltage between both terminals of the first resistance; an iron core saturation detection unit that, from the DC voltage outputted from the DC voltage generation unit, detects occurrence of iron core saturation of a transformer; and a short circuit unit that, when the occurrence of iron core saturation has been detected by the iron core saturation detection unit, causes both terminals of the secondary coil to short-circuit via a second resistance.

Description

鉄共振抑制装置及びそれを備えた電圧変成器Iron resonance suppression device and voltage transformer equipped with it
　本発明は、送電線又は電力設備において電圧を測定するための電圧変成器における鉄共振現象を抑制するための鉄共振抑制装置及びそれを備えた電圧変成器に関する。 The present invention relates to an iron resonance suppression device for suppressing an iron resonance phenomenon in a voltage transformer for measuring voltage in a transmission line or an electric power facility, and a voltage transformer provided therewith.
　鉄心を有する電力機器（変圧器、電圧変成器等）は、励磁インダクタンスＬを有す。一方、回路系には静電容量Ｃが共存している回路であるために、回路の開放及び接続時（遮断器等の開閉時）に、その過渡現象のため、励磁インダクタンスＬを構成する鉄心が一時的に磁気飽和し、Ｌ－Ｃ間でエネルギー授受が起き、その振動が持続して、異常音の発生、過熱による焼損、絶縁破壊等を引き起こすことがある。この現象は鉄共振現象として知られている。鉄共振現象は、鉄心の飽和現象を起点とする電気的擾乱現象である。 Power equipment with an iron core (transformer, voltage transformer, etc.) has an exciting inductance L. On the other hand, since the circuit system is a circuit in which the capacitance C coexists, the iron core constituting the exciting inductance L due to the transient phenomenon when the circuit is opened and connected (when the circuit breaker or the like is opened and closed). Is temporarily magnetically saturated, energy is transferred between the circuits, and the vibration is sustained, which may cause abnormal noise, burning due to overheating, dielectric breakdown, and the like. This phenomenon is known as the iron resonance phenomenon. The iron resonance phenomenon is an electrical disturbance phenomenon starting from the saturation phenomenon of the iron core.
　下記非特許文献１には、図４に示すように、鉄共振現象が、ａ：基本波過電圧モード（Ｆｕｎｄａｍｅｎｔａｌ　ｍｏｄｅ）、ｂ：分数調波モード（Ｓｕｂｈａｒｍｏｎｉｃ　ｍｏｄｅ）、ｃ：準周期モード（Ｑｕａｓｉ－ｐｅｒｉｏｄｉｃ　ｍｏｄｅ）、ｄ：カオテックモード（Ｃｈａｏｔｉｃ　ｍｏｄｅ）の４つのパターンに分類されることが開示されている。基本波過電圧モードは、基本波の振幅が大きくなり、３次、５次等の高調波が重畳した振動モードである。分数調波モードは、基本波に大きな分数調波（１／ｎ調波）の振動が加わった振動モードである。１／ｎ調波は、ｎを正の整数として、周波数が基本波の周波数の１／ｎ倍（周期が基本波の周期のｎ倍）である波を意味する。準周期モードは、２つの周波数の各々の整数倍の周波数間の差分周波数をもつ振動モードである。カオテックモードは、周期の特定が困難であり、カオス的な挙動をする振動モードである。 In Non-Patent Document 1 below, as shown in FIG. 4, the iron resonance phenomenon has a: fundamental overvoltage mode, b: subharmonic mode, and c: quasi-periodic mode. It is disclosed that it is classified into four patterns of periodic mode) and d: Chaotech mode (Chaotic mode). The fundamental wave overvoltage mode is a vibration mode in which the amplitude of the fundamental wave becomes large and harmonics such as third and fifth orders are superimposed. The fractional tuning mode is a vibration mode in which a large fractional tuning (1 / n tuning) vibration is added to the fundamental wave. The 1 / n tuning means a wave whose frequency is 1 / n times the frequency of the fundamental wave (the period is n times the period of the fundamental wave), where n is a positive integer. The quasi-periodic mode is a vibration mode having a difference frequency between frequencies that are integral multiples of each of the two frequencies. The chaotic mode is a vibration mode in which it is difficult to specify the period and the behavior is chaotic.
　鉄共振現象の対策として、例えば下記非特許文献２には、可飽和リアクトルを用いた回路構成が開示されている。具体的には、図５を参照して、直列接続の可飽和リアクトル９０２及び低抵抗値の抵抗９０４を、電圧変成器等のトランス９００の２次側巻線に並列に接続する。鉄共振現象が発生すると、発生した電圧により可飽和リアクトル９０２を飽和させ、発生した電流を抵抗９０４に流して共振エネルギーを吸収する。これにより、鉄共振現象は抑制される。 As a countermeasure against the iron resonance phenomenon, for example, Non-Patent Document 2 below discloses a circuit configuration using a saturable reactor. Specifically, with reference to FIG. 5, a saturable reactor 902 connected in series and a resistor 904 having a low resistance value are connected in parallel to the secondary winding of a transformer 900 such as a voltage transformer. When the iron resonance phenomenon occurs, the saturable reactor 902 is saturated by the generated voltage, and the generated current is passed through the resistor 904 to absorb the resonance energy. As a result, the iron resonance phenomenon is suppressed.
　また、下記特許文献１には、分数調波モードへの対策が開示されている。即ち、計器用変成器の２次側に、鉄共振特有の１／３調波、１／５調波及び基本波の過電圧を検出する回路を設け、この回路により鉄共振現象を検出して補助リレーを駆動し、低抵抗の負荷により共振エネルギーを吸収する。 Further, Patent Document 1 below discloses measures for the fractional wave adjustment mode. That is, a circuit for detecting the overvoltage of 1/3, 1/5, and fundamental waves peculiar to iron resonance is provided on the secondary side of the instrument transformer, and the iron resonance phenomenon is detected and assisted by this circuit. It drives a relay and absorbs resonance energy with a low resistance load.
特開２０１３－３８８２９号公報Japanese Unexamined Patent Publication No. 2013-38829
　しかし、非特許文献２に開示された対策では、状況によっては可飽和リアクトルが十分に飽和せず、鉄共振現象が継続する可能性がある。鉄共振現象が継続すると、場合によっては機器が焼損する。特許文献１に開示された対策では、半導体ＩＣを用いた複雑な回路を使用しており、その制御電力も外部から供給する必要があり、コストが高く、大型の装置になる。 However, with the measures disclosed in Non-Patent Document 2, the saturable reactor may not be sufficiently saturated depending on the situation, and the iron resonance phenomenon may continue. If the iron resonance phenomenon continues, the equipment may burn out. In the countermeasure disclosed in Patent Document 1, a complicated circuit using a semiconductor IC is used, and its control power also needs to be supplied from the outside, resulting in a high cost and a large-sized device.
　したがって、本発明は、可飽和リアクトルを用いた方式を採用し、鉄共振現象自体を表す鉄心の磁気飽和現象を従来よりも確実に検出でき、鉄共振現象を速やかに且つ効率的に抑制できる鉄共振抑制装置及びそれを備えた電圧変成器を提供することを目的とする。 Therefore, the present invention adopts a method using a saturable reactor, can detect the magnetic saturation phenomenon of the iron core representing the iron resonance phenomenon itself more reliably than before, and can suppress the iron resonance phenomenon quickly and efficiently. It is an object of the present invention to provide a resonance suppression device and a voltage modulator equipped with the resonance suppression device.
　本発明の第１の局面に係る鉄共振抑制装置は、鉄心及び当該鉄心に巻回された１次巻線及び２次巻線を有するトランスにおける鉄共振現象を抑制するための鉄共振抑制装置であって、一方の端子が２次巻線の一方の端子に接続された可飽和リアクトルと、可飽和リアクトルの他方の端子と２次巻線の他方の端子との間に接続された第１の抵抗と、第１の抵抗の両端子間の電圧を整流且つ平滑して直流電圧として出力する直流電圧生成部と、直流電圧生成部から出力される直流電圧からトランスの鉄心飽和の発生を検出する鉄心飽和検出部と、鉄心飽和検出部により鉄心飽和の発生が検出されたことを受けて、２次巻線の両端子を、第２の抵抗を介して短絡させる短絡部とを含む。 The iron resonance suppression device according to the first aspect of the present invention is an iron resonance suppression device for suppressing an iron resonance phenomenon in an iron core and a transformer having a primary winding and a secondary winding wound around the iron core. There is a saturable reactor in which one terminal is connected to one terminal in the secondary winding, and a first terminal connected between the other terminal in the saturable reactor and the other terminal in the secondary winding. The occurrence of iron core saturation of the transformer is detected from the DC voltage generator that rectifies and smoothes the voltage between both terminals of the resistor and the first resistor and outputs it as a DC voltage, and the DC voltage output from the DC voltage generator. It includes an iron core saturation detecting unit and a short-circuiting portion that short-circuits both terminals of the secondary winding via a second resistor in response to the detection of the occurrence of iron core saturation by the iron core saturation detecting unit.
　これにより、トランスを有する電圧変成器等において発生する鉄共振現象自体を表す鉄心の磁気飽和現象を従来よりも確実に検出でき、鉄共振現象を速やかに且つ効率的に抑制できる。 As a result, the magnetic saturation phenomenon of the iron core, which represents the iron resonance phenomenon itself generated in a voltage transformer or the like having a transformer, can be detected more reliably than before, and the iron resonance phenomenon can be suppressed quickly and efficiently.
　好ましくは、可飽和リアクトルのインピーダンスは、トランスの鉄心飽和が発生したときに、第１の抵抗のインピーダンスよりも小さくなるように設計する。これにより、速やかに鉄共振現象を抑制できる。 Preferably, the impedance of the saturable reactor is designed to be smaller than the impedance of the first resistor when the iron core of the transformer is saturated. As a result, the iron resonance phenomenon can be quickly suppressed.
　より好ましくは、可飽和リアクトルのインピーダンスは、トランスの鉄心飽和の発生が近づいたときに、第１の抵抗のインピーダンスよりも小さくなるように設計する。これにより、鉄共振現象が発生する前の段階、即ち鉄共振現象の兆候が発生した段階において、第２の抵抗によりそのエネルギーを消費させることができ、鉄共振現象の発生を抑制できる。 More preferably, the impedance of the saturable reactor is designed to be smaller than the impedance of the first resistor when the transformer core saturation approaches. As a result, the energy can be consumed by the second resistance at the stage before the iron resonance phenomenon occurs, that is, at the stage when the sign of the iron resonance phenomenon occurs, and the occurrence of the iron resonance phenomenon can be suppressed.
　さらに好ましくは、短絡部は、リレーであり、リレーの接点及び第２の抵抗は、直列接続され、２次巻線の両端子の間に接続され、鉄心飽和検出部は、リレーの接点を制御するコイルに直列接続されたスイッチング素子と、スイッチング素子を制御する定電圧素子とを含み、直列接続されたコイル及びスイッチング素子の両端子には、直流電圧生成部から出力された直流電圧が印加され、定電圧素子は、鉄心飽和の発生を検出したことを受けて、スイッチング素子をオンさせ、スイッチング素子がオンすることにより、コイルに電流が流れ、接点がオンする。これにより、リレーを駆動させるための電源を別途に設けることなく、リレーをオンさせて第２の抵抗により共振エネルギーを消費させ、鉄共振現象を抑制できる。したがって、小型の鉄共振抑制装置を実現できる。 More preferably, the short circuit is a relay, the contacts of the relay and the second resistor are connected in series and connected between both terminals of the secondary winding, and the core saturation detector controls the contacts of the relay. A DC voltage output from the DC voltage generator is applied to both terminals of the coil and the switching element connected in series, including a switching element connected in series to the coil to be connected and a constant voltage element to control the switching element. In response to the detection of the occurrence of iron core saturation, the constant voltage element turns on the switching element, and when the switching element is turned on, a current flows through the coil and the contacts are turned on. As a result, the iron resonance phenomenon can be suppressed by turning on the relay and consuming the resonance energy by the second resistor without separately providing a power source for driving the relay. Therefore, a small iron resonance suppression device can be realized.
　本発明の第２の局面に係る電圧変成器は、鉄心及び当該鉄心に巻回された１次巻線及び２次巻線を有するトランスと、上記の鉄共振抑制装置とを含み、鉄共振抑制装置は、トランスにおける鉄共振現象を抑制する。これにより、電圧変成器において発生する鉄共振現象自体を表す鉄心の磁気飽和現象を従来よりも確実に検出でき、鉄共振現象を速やかに且つ効率的に抑制できる。 The voltage transformer according to the second aspect of the present invention includes an iron core, a transformer having a primary winding and a secondary winding wound around the iron core, and the above-mentioned iron resonance suppression device, and suppresses iron resonance. The device suppresses the iron resonance phenomenon in the transformer. As a result, the magnetic saturation phenomenon of the iron core, which represents the iron resonance phenomenon itself generated in the voltage transformer, can be detected more reliably than before, and the iron resonance phenomenon can be suppressed quickly and efficiently.
　本発明によれば、電圧変成器等において発生する鉄共振現象自体を表す鉄心の磁気飽和現象を従来よりも確実に検出でき、鉄共振現象を速やかに且つ効率的に抑制できる。即ち、可飽和リアクトルをセンサとして使用することにより、可飽和リアクトルが不十分な飽和状態であっても、鉄共振現象を検出可能であり、鉄共振現象を速やかに抑制できる。 According to the present invention, the magnetic saturation phenomenon of the iron core, which represents the iron resonance phenomenon itself generated in the voltage transformer or the like, can be detected more reliably than before, and the iron resonance phenomenon can be suppressed quickly and efficiently. That is, by using the saturable reactor as a sensor, the iron resonance phenomenon can be detected even in a saturated state in which the saturable reactor is insufficient, and the iron resonance phenomenon can be quickly suppressed.
　また、鉄共振抑制装置は大電流が流れる回路ではなく、比較的小規模の回路として実現できる。したがって、既存の電圧変成器等に鉄共振抑制装置を内蔵させることも可能である。 Also, the iron resonance suppression device can be realized as a relatively small-scale circuit, not as a circuit through which a large current flows. Therefore, it is possible to incorporate an iron resonance suppression device into an existing voltage transformer or the like.
本発明の実施形態に係る電圧変成器の概略構成を示す回路図である。It is a circuit diagram which shows the schematic structure of the voltage transformer which concerns on embodiment of this invention. 変形例に係る電圧変成器の概略構成を示す回路図である。It is a circuit diagram which shows the schematic structure of the voltage transformer which concerns on a modification. 実施例に係る電圧変成器の概略構成を示す回路図である。It is a circuit diagram which shows the schematic structure of the voltage transformer which concerns on embodiment. 鉄共振現象の分類を示すグラフである。It is a graph which shows the classification of an iron resonance phenomenon. 従来の電圧変成器における鉄共振対策の構成を示す回路図である。It is a circuit diagram which shows the structure of iron resonance measures in the conventional voltage transformer.
　以下の実施形態では、同一の部品には同一の参照番号を付してある。それらの名称及び機能も同一である。したがって、それらについての詳細な説明は繰返さない。 In the following embodiments, the same parts are given the same reference number. Their names and functions are also the same. Therefore, detailed explanations about them will not be repeated.
　図１を参照して、本発明の実施形態に係る電圧変成器は、トランス２００と鉄共振抑制部１００とを備えている。トランス２００は電圧変成器の本体を構成するトランスであり、２次巻線から出力信号ＯＵＴを出力する。 With reference to FIG. 1, the voltage transformer according to the embodiment of the present invention includes a transformer 200 and an iron resonance suppression unit 100. The transformer 200 is a transformer that constitutes the main body of the voltage transformer, and outputs an output signal OUT from the secondary winding.
　鉄共振抑制部１００は、可飽和リアクトル１０２、整流平滑部１０４、アクティブ素子１０６、レベル検出部１０８、リレー部１１０、並びに、抵抗Ｒ１及びＲ２を含む。可飽和リアクトル１０２及び抵抗Ｒ１は直列接続されている。直列接続された可飽和リアクトル１０２及び抵抗Ｒ１は、トランス２００の２次巻線に並列接続されている。これにより、２次巻線に発生する交流電圧は、可飽和リアクトル１０２及び抵抗Ｒ１により分担される。 The iron resonance suppression unit 100 includes a saturable reactor 102, a rectifying smoothing unit 104, an active element 106, a level detection unit 108, a relay unit 110, and resistors R1 and R2. The saturable reactor 102 and the resistor R1 are connected in series. The saturable reactor 102 and the resistor R1 connected in series are connected in parallel to the secondary winding of the transformer 200. As a result, the AC voltage generated in the secondary winding is shared by the saturable reactor 102 and the resistor R1.
　可飽和リアクトル１０２は、例えば、急峻な磁気飽和特性を有する鉄心を備えており、上述したようにトランスの飽和特性を模擬して設計されている。即ち、トランスが飽和していない通常状態においては、同じように飽和せず大きいインピーダンスを有している。一方、トランスが飽和すると、又は、飽和に近づくと、可飽和リアクトル１０２が飽和し、インピーダンスは急激に減少する。可飽和リアクトル１０２は、飽和すると、そのインピーダンスが、抵抗Ｒ１のインピーダンスよりも十分に小さくなることが好ましい。なお、可飽和リアクトルの設計には、トランスの飽和特性に基づいてその２次電圧波形から飽和磁束密度を設計する手法が用いられる。 The saturable reactor 102 has, for example, an iron core having a steep magnetic saturation characteristic, and is designed by simulating the saturation characteristic of a transformer as described above. That is, in the normal state where the transformer is not saturated, it is not saturated and has a large impedance. On the other hand, when the transformer is saturated or approaches saturation, the saturable reactor 102 is saturated and the impedance decreases sharply. When the saturable reactor 102 is saturated, its impedance is preferably sufficiently smaller than the impedance of the resistor R1. For the design of the saturable reactor, a method of designing the saturation magnetic flux density from the secondary voltage waveform based on the saturation characteristics of the transformer is used.
　抵抗Ｒ１の両端子は、整流平滑部１０４の入力端子に接続されている。即ち、整流平滑部１０４の２つの入力端子の内、第１入力端子ｉｎ１は抵抗Ｒ１の一方の端子に接続され、第２入力端子ｉｎ２は抵抗Ｒ１の他方の端子に接続されている。ここでは、抵抗Ｒ１の一方の端子の電位をＶ１、他方の端子の電位をＶ２とする。整流平滑部１０４は、入力される抵抗Ｒ１の両端子間の交流電圧（Ｖ１－Ｖ２）を整流及び平滑し、２つの出力端子（第１出力端子ｏｕｔ１及び第２出力端子ｏｕｔ２）の間に直流電圧（Ｖ３－Ｖ４）を発生させる。ここでは、第１出力端子ｏｕｔ１の電位をＶ３とし、第２出力端子ｏｕｔ２の電位をＶ４としている。第２出力端子ｏｕｔ２の電位Ｖ４は、整流平滑部１０４から出力する直流電圧の基準電位である。 Both terminals of the resistor R1 are connected to the input terminals of the rectifying smoothing unit 104. That is, of the two input terminals of the rectifying smoothing unit 104, the first input terminal in1 is connected to one terminal of the resistor R1, and the second input terminal in2 is connected to the other terminal of the resistor R1. Here, the potential of one terminal of the resistor R1 is V1, and the potential of the other terminal is V2. The rectifying and smoothing unit 104 rectifies and smoothes the AC voltage (V1-V2) between both terminals of the input resistor R1, and direct current is applied between the two output terminals (first output terminal out1 and second output terminal out2). Generate a voltage (V3-V4). Here, the potential of the first output terminal out1 is V3, and the potential of the second output terminal out2 is V4. The potential V4 of the second output terminal out2 is a reference potential of the DC voltage output from the rectifying smoothing unit 104.
　整流平滑部１０４は、公知の整流回路及び平滑回路により構成できる。整流回路には、全波整流回路（例えば、４つのダイオードによるブリッジ回路）を使用することが好ましいが、半波整流回路であってもよい。平滑回路は、例えば、整流回路の出力端子間にコンデンサ（平滑コンデンサ）を設けることにより実現できる。平滑コンデンサは、整流回路により整流された電圧（脈流）を平滑し、一定の直流電圧を生成するためのものである。 The rectifying and smoothing unit 104 can be configured by a known rectifying circuit and smoothing circuit. A full-wave rectifier circuit (for example, a bridge circuit with four diodes) is preferably used as the rectifier circuit, but a half-wave rectifier circuit may be used. The smoothing circuit can be realized, for example, by providing a capacitor (smoothing capacitor) between the output terminals of the rectifier circuit. The smoothing capacitor is for smoothing the voltage (pulsating current) rectified by the rectifier circuit and generating a constant DC voltage.
　アクティブ素子１０６は、整流平滑部１０４の第１出力端子ｏｕｔ１と、リレー部１１０との間に接続されている。アクティブ素子１０６は、ゲートに入力される信号により制御されて、整流平滑部１０４の第１出力端子ｏｕｔ１とリレー部１１０とを短絡又は開放させるスイッチング素子としての機能を有する。アクティブ素子１０６のゲートには、レベル検出部１０８が接続されている。 The active element 106 is connected between the first output terminal out1 of the rectifying smoothing unit 104 and the relay unit 110. The active element 106 has a function as a switching element that is controlled by a signal input to the gate to short-circuit or open the first output terminal out1 of the rectifying smoothing unit 104 and the relay unit 110. A level detection unit 108 is connected to the gate of the active element 106.
　レベル検出部１０８は両端子間の電圧が一定値を超えると、その両端子間の電圧を一定値に維持する機能を有する。即ち、レベル検出部１０８は、整流平滑部１０４の第１出力端子ｏｕｔ１の電位Ｖ３が所定値以上になると、整流平滑部１０４の第１出力端子ｏｕｔ１の電位と、アクティブ素子１０６のゲートに接続されている端子の電位Ｖ５との差（電圧）を一定値に維持する。この一定値を、アクティブ素子１０６がオンするゲート電圧以上の値に設定しておけば、アクティブ素子１０６はオンする。 The level detection unit 108 has a function of maintaining the voltage between both terminals at a constant value when the voltage between both terminals exceeds a certain value. That is, when the potential V3 of the first output terminal out1 of the rectifying / smoothing unit 104 becomes equal to or higher than a predetermined value, the level detecting unit 108 is connected to the potential of the first output terminal out1 of the rectifying / smoothing unit 104 and the gate of the active element 106. The difference (voltage) from the potential V5 of the terminal is maintained at a constant value. If this constant value is set to a value equal to or higher than the gate voltage at which the active element 106 is turned on, the active element 106 is turned on.
　リレー部１１０は、例えば公知のリレーであり、内部接点をオンさせるためのコイルはアクティブ素子１０６及び整流平滑部１０４の第２出力端子ｏｕｔ２の間に接続されている。内部接点の一方の端子は抵抗Ｒ２に接続され、他方の端子は接地されている。抵抗Ｒ２のリレー部１１０に接続されていない端子は、トランス２００の出力ラインに接続されている。抵抗Ｒ２は、抵抗値が小さい抵抗であり、鉄共振現象による共振エネルギーを吸収するためのものである。 The relay unit 110 is, for example, a known relay, and a coil for turning on the internal contact is connected between the active element 106 and the second output terminal out2 of the rectifying smoothing unit 104. One terminal of the internal contact is connected to the resistor R2 and the other terminal is grounded. The terminal not connected to the relay portion 110 of the resistor R2 is connected to the output line of the transformer 200. The resistor R2 is a resistor having a small resistance value, and is for absorbing resonance energy due to the iron resonance phenomenon.
　鉄共振現象は変成器のトランスの鉄心が飽和することにより発生する。このように構成された鉄共振抑制部１００は、この現象が２次電圧に現れる波形を使って、対策を講じるものである。鉄共振抑制部１００は、次のように動作する。 The iron resonance phenomenon occurs when the iron core of the transformer of the transformer is saturated. The iron resonance suppression unit 100 configured in this way takes measures by using a waveform in which this phenomenon appears in the secondary voltage. The iron resonance suppression unit 100 operates as follows.
　鉄共振現象が発生していない通常状態においては、可飽和リアクトル１０２は飽和しておらず、大きいインピーダンスを有しており、トランス２００の２次巻線に発生する電圧は、殆ど可飽和リアクトル１０２により分担されており、抵抗Ｒ１の両端子間の電圧は小さい値である。したがって、整流平滑部１０４の入力電圧（交流）は小さく、整流平滑部１０４から出力される直流電圧（Ｖ３－Ｖ４）は小さく、レベル検出部１０８の両端子間の電圧は小さく、アクティブ素子１０６はオフのままである。そのため、リレー部１１０内部のコイルには電流が流れず、内部接点はオフのままであり、抵抗Ｒ２には電流は流れない。 In the normal state where the iron resonance phenomenon does not occur, the saturable reactor 102 is not saturated and has a large impedance, and the voltage generated in the secondary winding of the transformer 200 is almost the saturable reactor 102. The voltage between both terminals of the resistor R1 is a small value. Therefore, the input voltage (alternating current) of the rectifying and smoothing unit 104 is small, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104 is small, the voltage between both terminals of the level detecting unit 108 is small, and the active element 106 is It remains off. Therefore, no current flows through the coil inside the relay unit 110, the internal contacts remain off, and no current flows through the resistor R2.
　鉄共振現象が発生し、トランス２００の１次巻線に流れる過大な飽和時の励磁電流により鉄心が飽和すると、その２次電圧には特有の波形（分数調波の発生等）が現れる。この波形を受けて可飽和リアクトル１０２は飽和領域に達して、このときそのインピーダンスは急激に減少する（抵抗Ｒ１のインピーダンスよりも十分に小さくなる）。それにより、トランス２００の２次巻線に発生する電圧は、殆ど抵抗Ｒ１により分担され、抵抗Ｒ１の両端子間の電圧は急激に増大する。この現象は交流信号であるため、非飽和－飽和状態を繰返す。したがって、飽和状態になったときに整流平滑部１０４の入力電圧（交流）は増大し、整流平滑部１０４から出力される直流電圧（Ｖ３－Ｖ４）も大きくなる。レベル検出部１０８の両端子間の電圧は一定値（アクティブ素子１０６をオンさせる電圧も大）になり、アクティブ素子１０６はオンし、整流平滑部１０４の第１出力端子ｏｕｔ１及び第２出力端子ｏｕｔ２は、リレー部１１０のコイルに接続され、コイルに電流が流れる。これにより、リレー部１１０の内部接点がオンして、抵抗Ｒ２が接地され、鉄共振現象によりトランス２００の２次巻線に発生した電圧は抵抗Ｒ２に接続（印加）され、電流が流れる。したがって、鉄共振エネルギーが消費され、現象を抑制できる。 When an iron resonance phenomenon occurs and the iron core is saturated due to an excessively saturated exciting current flowing through the primary winding of the transformer 200, a peculiar waveform (generation of fractional tuning, etc.) appears in the secondary voltage. In response to this waveform, the saturable reactor 102 reaches the saturation region, at which time its impedance sharply decreases (sufficiently smaller than the impedance of the resistor R1). As a result, the voltage generated in the secondary winding of the transformer 200 is almost shared by the resistor R1, and the voltage between both terminals of the resistor R1 rapidly increases. Since this phenomenon is an AC signal, the unsaturated-saturated state is repeated. Therefore, when the saturated state is reached, the input voltage (alternating current) of the rectifying and smoothing unit 104 increases, and the DC voltage (V3-V4) output from the rectifying and smoothing unit 104 also increases. The voltage between both terminals of the level detection unit 108 becomes a constant value (the voltage that turns on the active element 106 is also large), the active element 106 is turned on, and the first output terminal out1 and the second output terminal out2 of the rectifying smoothing unit 104 are turned on. Is connected to the coil of the relay unit 110, and a current flows through the coil. As a result, the internal contact of the relay unit 110 is turned on, the resistor R2 is grounded, the voltage generated in the secondary winding of the transformer 200 due to the iron resonance phenomenon is connected (applied) to the resistor R2, and a current flows. Therefore, iron resonance energy is consumed and the phenomenon can be suppressed.
　鉄共振現象が抑制されると、トランス２００の１次巻線に流れる電流は通常レベルに戻り、鉄共振抑制部１００は通常状態に戻る。即ち、可飽和リアクトル１０２は飽和しなくなり、そのインピーダンスは大きくなり、トランス２００の２次巻線に発生する電圧は、殆ど可飽和リアクトル１０２により分担され、抵抗Ｒ１の両端子間の電圧は小さくなる。即ち、整流平滑部１０４の入力電圧（交流）は小さくなり、整流平滑部１０４から出力される直流電圧（Ｖ３－Ｖ４）、及びレベル検出部１０８の両端子間の電圧は小さくなり、アクティブ素子１０６はオフする。そのため、リレー部１１０の内部接点はオフし、抵抗Ｒ２には電流は流れなくなる。 When the iron resonance phenomenon is suppressed, the current flowing through the primary winding of the transformer 200 returns to the normal level, and the iron resonance suppression unit 100 returns to the normal state. That is, the saturable reactor 102 is no longer saturated, its impedance becomes large, the voltage generated in the secondary winding of the transformer 200 is almost shared by the saturable reactor 102, and the voltage between both terminals of the resistor R1 becomes small. .. That is, the input voltage (alternating current) of the rectifying and smoothing unit 104 becomes small, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104, and the voltage between both terminals of the level detecting unit 108 become small, and the active element 106 Turns off. Therefore, the internal contact of the relay unit 110 is turned off, and no current flows through the resistor R2.
　このように、可飽和リアクトル１０２を、鉄共振現象自体の本質を表すトランスの鉄心の磁気飽和現象を検出するためのセンサとして使用することにより、鉄共振現象を抑制できる。鉄共振抑制部１００は大電流が流れる回路ではなく、比較的小規模の回路として実現できる。また、整流平滑部１０４、アクティブ素子１０６及びレベル検出部１０８を、鉄共振現象の発生時にリレー部１１０を駆動させるための制御電源として使用しているので、リレー部１１０を駆動するための電源を別途に設けることも、リレー部１１０を駆動する電圧を外部電源から供給することも不要である。したがって、鉄共振抑制部１００を安価且つコンパクトに製造でき、既存の電圧変成器に鉄共振抑制部１００を内蔵させることも可能である。 In this way, the iron resonance phenomenon can be suppressed by using the saturable reactor 102 as a sensor for detecting the magnetic saturation phenomenon of the iron core of the transformer, which represents the essence of the iron resonance phenomenon itself. The iron resonance suppression unit 100 can be realized as a relatively small-scale circuit, not as a circuit through which a large current flows. Further, since the rectifying smoothing unit 104, the active element 106, and the level detecting unit 108 are used as a control power source for driving the relay unit 110 when the iron resonance phenomenon occurs, the power source for driving the relay unit 110 is used. It is not necessary to separately provide it or to supply the voltage for driving the relay unit 110 from an external power source. Therefore, the iron resonance suppression unit 100 can be manufactured inexpensively and compactly, and the iron resonance suppression unit 100 can be incorporated in an existing voltage transformer.
　（変形例）
　上記の実施形態では、アクティブ素子１０６が、整流平滑部１０４の第１出力端子ｏｕｔ１とリレー部１１０との間に接続されている場合を説明したが、これに限定されない。アクティブ素子１０６は、整流平滑部１０４の第２出力端子ｏｕｔ２とリレー部１１０との間に接続されてもよい。 (Modification example)
In the above embodiment, the case where the active element 106 is connected between the first output terminal out1 of the rectifying smoothing unit 104 and the relay unit 110 has been described, but the present invention is not limited to this. The active element 106 may be connected between the second output terminal out2 of the rectifying smoothing unit 104 and the relay unit 110.
　図２を参照して、本変形例に係る電圧変成器は、トランス２００と鉄共振抑制部１３０とを備えている。トランス２００は電圧変成器の本体を構成するトランスであり、２次巻線から出力信号ＯＵＴを出力する。 With reference to FIG. 2, the voltage transformer according to this modification includes a transformer 200 and an iron resonance suppression unit 130. The transformer 200 is a transformer that constitutes the main body of the voltage transformer, and outputs an output signal OUT from the secondary winding.
　鉄共振抑制部１３０は、図１に示した鉄共振抑制部１００と同じ構成要素を含む。即ち、鉄共振抑制部１３０は、可飽和リアクトル１０２、整流平滑部１０４、アクティブ素子１０６、レベル検出部１０８、リレー部１１０、並びに、抵抗Ｒ１及びＲ２を含む。鉄共振抑制部１３０が鉄共振抑制部１００と異なるのは、アクティブ素子１０６とその周辺要素との接続関係だけであり、各要素の機能は鉄共振抑制部１００と同じである。したがって、以下においては、重複説明を繰返さず、主として鉄共振抑制部１００と異なる点に関して説明する。 The iron resonance suppression unit 130 includes the same components as the iron resonance suppression unit 100 shown in FIG. That is, the iron resonance suppression unit 130 includes a saturable reactor 102, a rectifying smoothing unit 104, an active element 106, a level detection unit 108, a relay unit 110, and resistors R1 and R2. The iron resonance suppression unit 130 differs from the iron resonance suppression unit 100 only in the connection relationship between the active element 106 and its peripheral elements, and the function of each element is the same as that of the iron resonance suppression unit 100. Therefore, in the following, the duplicate description will not be repeated, and the points different from the iron resonance suppression unit 100 will be mainly described.
　アクティブ素子１０６は、整流平滑部１０４の第２出力端子ｏｕｔ２と、リレー部１１０（具体的には、内部コイルの一端）との間に接続されている。アクティブ素子１０６は、ゲートに入力される信号により制御されて、整流平滑部１０４の第２出力端子ｏｕｔ２とリレー部１１０とを短絡又は開放させる。整流平滑部１０４の第１出力端子ｏｕｔ１は、リレー部１１０（内部コイルの他端）に直接接続されている。 The active element 106 is connected between the second output terminal out2 of the rectifying smoothing unit 104 and the relay unit 110 (specifically, one end of the internal coil). The active element 106 is controlled by a signal input to the gate to short-circuit or open the second output terminal out2 of the rectifying smoothing unit 104 and the relay unit 110. The first output terminal out1 of the rectifying and smoothing unit 104 is directly connected to the relay unit 110 (the other end of the internal coil).
　このように構成された鉄共振抑制部１３０は、図１の鉄共振抑制部１００と同様に動作する。即ち、鉄共振現象が発生していない通常状態においては、可飽和リアクトル１０２は飽和しておらず、大きいインピーダンスを有しており、トランス２００の２次巻線に発生する電圧は、殆ど可飽和リアクトル１０２により分担されており、抵抗Ｒ１の両端子間の電圧は小さい値である。したがって、整流平滑部１０４の入力電圧（交流）は小さく、整流平滑部１０４から出力される直流電圧（Ｖ３－Ｖ４）及びレベル検出部１０８の両端子間の電圧は小さく、アクティブ素子１０６及びリレー部１１０の内部接点はオフのままであり、抵抗Ｒ２には電流は流れない。 The iron resonance suppression unit 130 configured in this way operates in the same manner as the iron resonance suppression unit 100 of FIG. That is, in the normal state where the iron resonance phenomenon does not occur, the saturable reactor 102 is not saturated and has a large impedance, and the voltage generated in the secondary winding of the transformer 200 is almost saturable. It is shared by the reactor 102, and the voltage between both terminals of the resistor R1 is a small value. Therefore, the input voltage (alternating current) of the rectifying and smoothing unit 104 is small, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104 and the voltage between both terminals of the level detection unit 108 are small, and the active element 106 and the relay unit The internal contacts of 110 remain off and no current flows through resistor R2.
　鉄共振現象が発生すると、可飽和リアクトル１０２は飽和して、そのインピーダンスは急激に減少する。それにより、トランス２００の２次巻線に発生する電圧は、殆ど抵抗Ｒ１により分担され、抵抗Ｒ１の両端子間の電圧は急激に増大する。したがって、整流平滑部１０４の入力電圧（交流）が増大し、整流平滑部１０４から出力される直流電圧（Ｖ３－Ｖ４）、及びレベル検出部１０８の両端子間の電圧は増大し、アクティブ素子１０６はオンし、整流平滑部１０４の第１出力端子ｏｕｔ１及び第２出力端子ｏｕｔ２は、リレー部１１０のコイルに接続され、コイルに電流が流れる。これにより、リレー部１１０の内部接点がオンして、抵抗Ｒ２が接地され、鉄共振現象によりトランス２００の２次巻線に発生した電圧は抵抗Ｒ２に接続され、電流が流れる。したがって、鉄共振エネルギーが消費され、現象を抑制できる。 When the iron resonance phenomenon occurs, the saturable reactor 102 is saturated and its impedance sharply decreases. As a result, the voltage generated in the secondary winding of the transformer 200 is almost shared by the resistor R1, and the voltage between both terminals of the resistor R1 rapidly increases. Therefore, the input voltage (alternating current) of the rectifying and smoothing unit 104 increases, the DC voltage (V3-V4) output from the rectifying and smoothing unit 104, and the voltage between both terminals of the level detection unit 108 increase, and the active element 106 Is turned on, and the first output terminal out1 and the second output terminal out2 of the rectifying smoothing unit 104 are connected to the coil of the relay unit 110, and a current flows through the coil. As a result, the internal contact of the relay unit 110 is turned on, the resistor R2 is grounded, the voltage generated in the secondary winding of the transformer 200 due to the iron resonance phenomenon is connected to the resistor R2, and a current flows. Therefore, iron resonance energy is consumed and the phenomenon can be suppressed.
　鉄共振現象が抑制されると、トランス２００の１次巻線に流れる電流は通常レベルに戻り、鉄共振抑制部１３０は通常状態に戻る。 When the iron resonance phenomenon is suppressed, the current flowing through the primary winding of the transformer 200 returns to the normal level, and the iron resonance suppression unit 130 returns to the normal state.
　このように、鉄共振抑制部１３０においても、上記したように、可飽和リアクトル１０２を、鉄心の磁気飽和現象を検出するためのセンサとして使用することにより、可飽和リアクトル１０２が不十分な飽和状態であっても、鉄共振現象を抑制できる。また、リレー部１１０を駆動するための電源を別途に設けることも、リレー部１１０を駆動する電圧を外部電源から供給することも不要であり、鉄共振抑制部１３０を安価且つコンパクトに形成でき、既存の電圧変成器に鉄共振抑制部１３０を内蔵させることも可能である。 As described above, in the iron resonance suppression unit 130 as well, as described above, by using the saturable reactor 102 as a sensor for detecting the magnetic saturation phenomenon of the iron core, the saturable reactor 102 is in an insufficient saturated state. Even so, the iron resonance phenomenon can be suppressed. Further, it is not necessary to separately provide a power source for driving the relay unit 110 or to supply a voltage for driving the relay unit 110 from an external power source, and the iron resonance suppression unit 130 can be formed inexpensively and compactly. It is also possible to incorporate the iron resonance suppression unit 130 into an existing voltage transformer.
　（実施例）
　より具体的な回路構成を実施例として示す。図２に対応する実施例を図３に示す。図３を参照して、整流平滑部１０４は全波整流回路１１４及びコンデンサＣ１により構成されている。アクティブ素子１０６及びレベル検出部１０８はそれぞれ、トランジスタ１１６及びツェナーダイオード１１８により構成されている。 (Example)
A more specific circuit configuration is shown as an example. An embodiment corresponding to FIG. 2 is shown in FIG. With reference to FIG. 3, the rectifying smoothing section 104 is composed of a full-wave rectifying circuit 114 and a capacitor C1. The active element 106 and the level detection unit 108 are composed of a transistor 116 and a Zener diode 118, respectively.
　図３を参照して、全波整流回路１１４の一方の出力端子（電位Ｖ３の端子）は、ツェナーダイオード１１８及び抵抗Ｒ５を介してトランジスタ１１６のベース端子に接続されている。抵抗Ｒ５は、トランジスタ１１６のベース電流を制限するための抵抗である。 With reference to FIG. 3, one output terminal (terminal of potential V3) of the full-wave rectifier circuit 114 is connected to the base terminal of the transistor 116 via a Zener diode 118 and a resistor R5. The resistor R5 is a resistor for limiting the base current of the transistor 116.
　全波整流回路１１４の一方の出力端子（電位Ｖ３の端子）は、抵抗Ｒ６を介してリレー部１１０（内部のコイル）にも接続されている。抵抗Ｒ６は、トランジスタ１１６がオンしたときにリレー部１１０内部のコイル及びトランジスタ１１６に流れる電流を調整するためのものである。 One output terminal (terminal of potential V3) of the full-wave rectifier circuit 114 is also connected to the relay unit 110 (internal coil) via a resistor R6. The resistor R6 is for adjusting the current flowing through the coil inside the relay unit 110 and the transistor 116 when the transistor 116 is turned on.
　図３のように構成された鉄共振抑制部は、鉄共振現象を抑制できる。鉄共振現象が発生して、抵抗Ｒ１の両端子間の電圧、即ち全波整流回路１１４の入力電圧（交流）が急激に増大すると、全波整流回路１１４から出力される電圧（Ｖ３－Ｖ４）は増大する。抵抗Ｒ５の一方の端子が接続されているツェナーダイオード１１８のカソードの電位は、全波整流回路１１４から出力される電圧がコンデンサＣ１により平滑されて生成された直流電圧になり、トランジスタ１１６のゲートには、抵抗Ｒ５を介してトランジスタ１１６をオンさせるベース電流が流れる。トランジスタ１１６がオンすることにより、全波整流回路１１４の２つの出力端子からリレー部１１０のコイルに電圧が印加され、コイルに電流が流れ、リレー部１１０の内部接点がオンして抵抗Ｒ２が接地され、鉄共振現象によりトランス２００の２次巻線に発生した電圧は抵抗Ｒ２に接続され、電流が流れる。これにより、鉄共振エネルギーが消費され、現象を抑制できる。 The iron resonance suppression unit configured as shown in FIG. 3 can suppress the iron resonance phenomenon. When an iron resonance phenomenon occurs and the voltage between both terminals of the resistor R1, that is, the input voltage (alternating current) of the full-wave rectifier circuit 114 suddenly increases, the voltage (V3-V4) output from the full-wave rectifier circuit 114. Will increase. The potential of the cathode of the Zener diode 118 to which one terminal of the resistor R5 is connected becomes the DC voltage generated by smoothing the voltage output from the full-wave rectifier circuit 114 by the capacitor C1 and becomes the gate of the transistor 116. A base current that turns on the transistor 116 flows through the resistor R5. When the transistor 116 is turned on, a voltage is applied to the coil of the relay unit 110 from the two output terminals of the full-wave rectifying circuit 114, a current flows through the coil, the internal contact of the relay unit 110 is turned on, and the resistor R2 is grounded. The voltage generated in the secondary winding of the transformer 200 due to the iron resonance phenomenon is connected to the resistor R2, and a current flows. As a result, iron resonance energy is consumed and the phenomenon can be suppressed.
　上記では、アクティブ素子１０６をＮチャネルトランジスタで構成する場合を説明したが、これに限定されない。ＮチャネルＭＯＳＦＥＴを使用してもよい。ＭＯＳＦＥＴ以外のＦＥＴを使用してもよい。 In the above, the case where the active element 106 is composed of N-channel transistors has been described, but the present invention is not limited to this. N-channel MOSFETs may be used. FETs other than MOSFETs may be used.
　以上、実施の形態を説明することにより本発明を説明したが、上記した実施の形態は例示であって、本発明は上記した実施の形態のみに制限されるわけではない。本発明の範囲は、発明の詳細な説明の記載を参酌した上で、請求の範囲の各請求項によって示され、そこに記載された文言と均等の意味及び範囲内での全ての変更を含む。 Although the present invention has been described above by explaining the embodiments, the above-described embodiments are examples, and the present invention is not limited to the above-described embodiments. The scope of the present invention is indicated by each claim of the claims, taking into consideration the description of the detailed description of the invention, and includes all modifications within the meaning and scope equivalent to the wording described therein. ..
　本発明によれば、電圧変成器等において発生する鉄共振現象自体を表す鉄心の磁気飽和現象を検出でき、鉄共振現象を速やかに且つ効率的に抑制できる。 According to the present invention, the magnetic saturation phenomenon of the iron core, which represents the iron resonance phenomenon itself generated in a voltage transformer or the like, can be detected, and the iron resonance phenomenon can be suppressed quickly and efficiently.
１００、１３０　　鉄共振抑制部
１０２、９０２　　可飽和リアクトル
１０４　　整流平滑部
１０６　　アクティブ素子
１０８　　レベル検出部
１１０　　リレー部
１１４　　全波整流回路
１１６　　トランジスタ
１１８　　ツェナーダイオード
２００、９００　　トランス
９０４、Ｒ１、Ｒ２、Ｒ５、Ｒ６　　抵抗
ｉｎ１　　第１入力端子
ｉｎ２　　第２入力端子
ｏｕｔ１　　第１出力端子
ｏｕｔ２　　第２出力端子
Ｃ１　　コンデンサ
Ｖ１、Ｖ２、Ｖ３、Ｖ４、Ｖ５、Ｖ６　　電位 100, 130 Iron resonance suppression part 102, 902 Saturable reactor 104 Rectifier smoothing part 106 Active element 108 Level detection part 110 Relay part 114 Full-wave rectifier circuit 116 Transistor 118 Zener diode 200, 900 Transformer 904, R1, R2, R5, R6 Resistor in1 1st input terminal in2 2nd input terminal out1 1st output terminal out2 2nd output terminal C1 Capacitors V1, V2, V3, V4, V5, V6 Potential

Claims (5)

  1. 　鉄心及び当該鉄心に巻回された１次巻線及び２次巻線を有するトランスにおける鉄共振現象を抑制するための鉄共振抑制装置であって、
    　一方の端子が前記２次巻線の一方の端子に接続された可飽和リアクトルと、
    　前記可飽和リアクトルの他方の端子と前記２次巻線の他方の端子との間に接続された第１の抵抗と、
    　前記第１の抵抗の両端子間の電圧を整流且つ平滑して直流電圧として出力する直流電圧生成部と、
    　前記直流電圧生成部から出力される前記直流電圧から前記トランスの鉄心飽和の発生を検出する鉄心飽和検出部と、
    　前記鉄心飽和検出部により前記鉄心飽和の発生が検出されたことを受けて、前記２次巻線の両端子を、第２の抵抗を介して短絡させる短絡部とを含むことを特徴とする鉄共振抑制装置。     An iron resonance suppression device for suppressing an iron resonance phenomenon in an iron core and a transformer having a primary winding and a secondary winding wound around the iron core.
    With a saturable reactor in which one terminal is connected to one terminal of the secondary winding,
    A first resistor connected between the other terminal of the saturable reactor and the other terminal of the secondary winding,
    A DC voltage generator that rectifies and smoothes the voltage between both terminals of the first resistor and outputs it as a DC voltage.
    An iron core saturation detection unit that detects the occurrence of iron core saturation of the transformer from the DC voltage output from the DC voltage generation unit, and
    An iron characterized by including a short-circuit portion for short-circuiting both terminals of the secondary winding via a second resistor in response to the detection of the occurrence of the iron core saturation by the iron core saturation detection unit. Resonance suppression device.
  2. 　前記可飽和リアクトルのインピーダンスは、前記トランスの鉄心飽和が発生したときに、前記第１の抵抗のインピーダンスよりも小さくなることを特徴とする、請求項１に記載の鉄共振抑制装置。 The iron resonance suppression device according to claim 1, wherein the impedance of the saturable reactor becomes smaller than the impedance of the first resistor when the iron core of the transformer is saturated.
  3. 　前記可飽和リアクトルのインピーダンスは、前記トランスの鉄心飽和の発生が近づいたときに、前記第１の抵抗のインピーダンスよりも小さくなることを特徴とする、請求項１に記載の鉄共振抑制装置。 The iron resonance suppression device according to claim 1, wherein the impedance of the saturable reactor becomes smaller than the impedance of the first resistor when the occurrence of iron core saturation of the transformer approaches.
  4. 　前記短絡部は、リレーであり、
    　前記リレーの接点及び前記第２の抵抗は、直列接続され、前記２次巻線の両端子の間に接続され、
    　前記鉄心飽和検出部は、
    　　前記リレーの前記接点を制御するコイルに直列接続されたスイッチング素子と、
    　　前記スイッチング素子を制御する定電圧素子とを含み、
    　直列接続された前記コイル及び前記スイッチング素子の両端子には、前記直流電圧生成部から出力される前記直流電圧が印加され、
    　前記定電圧素子は、前記鉄心飽和の発生を検出したことを受けて、前記スイッチング素子をオンさせ、
    　前記スイッチング素子がオンすることにより、前記コイルに電流が流れ、前記接点がオンすることを特徴とする請求項１から請求項３のいずれか１項に記載の鉄共振制御装置。     The short-circuited portion is a relay.
    The contact of the relay and the second resistor are connected in series and connected between both terminals of the secondary winding.
    The iron core saturation detection unit
    A switching element connected in series to a coil that controls the contact of the relay,
    Including a constant voltage element that controls the switching element
    The DC voltage output from the DC voltage generator is applied to both terminals of the coil and the switching element connected in series.
    In response to the detection of the occurrence of iron core saturation, the constant voltage element turns on the switching element.
    The iron resonance control device according to any one of claims 1 to 3, wherein a current flows through the coil when the switching element is turned on, and the contact is turned on.
  5. 　鉄心及び当該鉄心に巻回された１次巻線及び２次巻線を有するトランスと、
    　請求項１から請求項４のいずれか１項に記載の鉄共振抑制装置とを含み、
    　前記鉄共振抑制装置は、前記トランスにおける鉄共振現象を抑制することを特徴とする電圧変成器。     An iron core and a transformer having a primary winding and a secondary winding wound around the iron core,
    The iron resonance suppression device according to any one of claims 1 to 4 is included.
    The iron resonance suppression device is a voltage transformer characterized by suppressing an iron resonance phenomenon in the transformer.
PCT/JP2019/012065 2019-03-22 2019-03-22 Ferroresonance suppression device and voltage transformer provided with same WO2020194373A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4109730A1 (en) * 2021-06-25 2022-12-28 Sungrow Power Supply Co., Ltd. Isolated bidirectional converter and method for controlling the same

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JPS59162714A (en) * 1983-03-04 1984-09-13 日新電機株式会社 Transforming device for instrument
JPS59202615A (en) * 1983-04-30 1984-11-16 Nissin Electric Co Ltd Potential transformer
JPS6039230U (en) * 1983-08-24 1985-03-19 日新電機株式会社 Instrument transformer
JPS6127430U (en) * 1984-07-23 1986-02-19 日新電機株式会社 Instrument transformer
JPH04331415A (en) * 1991-04-26 1992-11-19 Toshiba Corp Transformer for measuring instrument

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59162714A (en) * 1983-03-04 1984-09-13 日新電機株式会社 Transforming device for instrument
JPS59202615A (en) * 1983-04-30 1984-11-16 Nissin Electric Co Ltd Potential transformer
JPS6039230U (en) * 1983-08-24 1985-03-19 日新電機株式会社 Instrument transformer
JPS6127430U (en) * 1984-07-23 1986-02-19 日新電機株式会社 Instrument transformer
JPH04331415A (en) * 1991-04-26 1992-11-19 Toshiba Corp Transformer for measuring instrument

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4109730A1 (en) * 2021-06-25 2022-12-28 Sungrow Power Supply Co., Ltd. Isolated bidirectional converter and method for controlling the same

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