JP3236223B2 - Transformer excitation surge suppression circuit - Google Patents
Transformer excitation surge suppression circuitInfo
- Publication number
- JP3236223B2 JP3236223B2 JP21340296A JP21340296A JP3236223B2 JP 3236223 B2 JP3236223 B2 JP 3236223B2 JP 21340296 A JP21340296 A JP 21340296A JP 21340296 A JP21340296 A JP 21340296A JP 3236223 B2 JP3236223 B2 JP 3236223B2
- Authority
- JP
- Japan
- Prior art keywords
- resistor
- transformer
- power supply
- voltage
- relay
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Emergency Protection Circuit Devices (AREA)
- Control Of Voltage And Current In General (AREA)
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、トランスに電源を
投入する際に発生する励磁突流を抑制するための励磁突
流抑制回路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exciting sudden flow suppressing circuit for suppressing an exciting sudden flow that occurs when power is supplied to a transformer.
【０００２】[0002]
【従来の技術】変圧器の励磁電流は、通常、定格電流の
２〜５％程度であるが、電源を投入する際の電源電圧の
位相によっては、定格電流の数倍から２０倍近く流れる
ことがある。これを励磁突入電流または単に励磁突流と
呼んでいる。この励磁突流は、トランスが接続されてい
る機器、設備等に悪影響を及ぼすものである。そのた
め、従来から励磁突流を低減する対策が、種々提案され
ている。図３は、一般的な対策の一例を示すものであ
る。図では、１００ボルト等の商用電源１と、負荷５が
接続されたトランス２との間に、抵抗３、開閉器４を直
列に接続したものである。すなわち、開閉器４を閉じ
て、トランス２へ電源を投入すると、励磁突流は、抵抗
３により抑制される。なお、抵抗３の代わりにサーミス
ターを用いることもある。2. Description of the Related Art The exciting current of a transformer is usually about 2 to 5% of the rated current. However, depending on the phase of the power supply voltage when the power is turned on, it may flow from several times to nearly 20 times the rated current. There is. This is called an exciting rush current or simply an exciting rush current. This exciting jet has an adverse effect on devices, equipment, and the like to which the transformer is connected. For this reason, various measures have conventionally been proposed to reduce the exciting jet flow. FIG. 3 shows an example of a general countermeasure. In the figure, a resistor 3 and a switch 4 are connected in series between a commercial power supply 1 of 100 volts or the like and a transformer 2 to which a load 5 is connected. That is, when the switch 4 is closed and the power is turned on to the transformer 2, the exciting current is suppressed by the resistor 3. Note that a thermistor may be used instead of the resistor 3.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、図３に
示した従来例では、抑制用の抵抗またはサーミスターを
接続したことにより、電源投入時の励磁突流を減少させ
ることができるものの、その分、通常状態での消費電力
の増加、発熱、電圧降下等も発生する。そのため、励磁
突流の抑制を目的として抵抗またはサーミスターを接続
しようとすると、種々の制約を受けることになり、必ず
しも充分な対策ではなかった。However, in the prior art shown in FIG. 3, the connection of the suppressing resistor or the thermistor can reduce the exciting sudden flow when the power is turned on. In the normal state, an increase in power consumption, heat generation, voltage drop, and the like also occur. For this reason, if a resistor or thermistor is connected for the purpose of suppressing an exciting current, various restrictions are imposed, and this is not always a sufficient measure.
【０００４】 そこで上記課題を解決するために、本発
明は、商用電源とトランスの電源側巻線の一端との間
に、開閉器を介して第１の抵抗と第２の抵抗とを直列に
接続し、第１の抵抗に並列にリレー接点を接続して第１
のバイパス回路を構成すると共に、第２の抵抗に並列に
リレー接点を接続して第２のバイパス回路を構成し、第
１の抵抗と第２の抵抗との相互の接続点と、前記電源側
巻線の他端との間に、前記両リレー接点開閉用の電磁コ
イルを接続し、前記開閉器の投入直後には前記第１の抵
抗及び第２の抵抗によりトランスに対する励磁突流を抑
制し、その後に上昇した前記電源側巻線の両端電圧によ
り前記電磁コイルを作動させて前記両リレー接点を閉じ
るものである。このため、トランスへの電源投入直後に
発生する励磁突流は第１及び第２の抵抗によって抑制さ
れる。その後、トランスの鉄心の飽和が解除され、トラ
ンスのインピーダンスが大きくなって電源側巻線の両端
電圧が上昇し、電磁コイルの作動電圧に達すると、第１
及び第２のバイパス回路の両リレー接点が閉じて第１及
び第２の抵抗がバイパスされる。これにより、定常状態
での抵抗による電圧降下や電力消費が解消される。ま
た、第１及び第２の抵抗の抵抗値を変えてその抵抗値比
を変えることにより、励磁電流の値に応じて最適なタイ
ミングで電磁コイルを作動させて両抵抗をバイパスさせ
ることができる。 In order to solve the above problems, the present invention
Between the commercial power supply and one end of the power supply side winding of the transformer.
And a first resistor and a second resistor connected in series via a switch.
Connect the relay contact in parallel with the first resistor
In parallel with the second resistor
Forming a second bypass circuit by connecting the relay contacts,
A mutual connection point between the first resistor and the second resistor;
An electromagnetic core for opening and closing the two relay contacts is provided between the other end of the winding.
Connected to the first switch immediately after the switch is turned on.
Suppression of exciting current to transformer by resistance and second resistance
The voltage across the power supply side winding
Actuate the electromagnetic coil to close both relay contacts.
Things. Therefore, immediately after powering on the transformer
The generated exciting jet is suppressed by the first and second resistors.
It is. After that, the saturation of the transformer core is released,
Impedance of the power supply side winding
When the voltage rises and reaches the operating voltage of the electromagnetic coil, the first
And both relay contacts of the second bypass circuit are closed and the first and second bypass circuits are closed.
And the second resistor is bypassed. This allows steady state
The voltage drop and the power consumption due to the resistance at the terminal are eliminated. Ma
Further, the resistance value ratio of the first and second resistors is changed.
By changing the value of the excitation current.
Activate the electromagnetic coil to bypass both resistors
Can be
【０００５】[0005]
【０００６】 以下、図に沿って本発明の実施形態を説
明する。まず、図１は本発明の原理を説明する回路図で
ある。図において、１は１００ボルト等の商用電源であ
り、この電源１と、負荷５が接続されたトランス２の電
源側巻線との間に開閉器４，抵抗３が直列に接続されて
いる。抵抗３は開閉器４の投入時のトランス２の励磁突
流を抑制するためのものであり、この抵抗３に対して並
列にバイパス回路を構成するリレー接点６が接続されて
いる。また、トランス２の電源側巻線には電磁コイル７
が並列に接続されており、この電磁コイル７への通電に
よってリレー接点６が閉じるようになっている。なお、
リレー接点６はメイク接点である。Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, FIG. 1 is a circuit diagram illustrating the principle of the present invention.
is there. In the figure, 1 is a commercial power supply such as 100 volts.
Power supply 1 and the power supply of the transformer 2 to which the load 5 is connected.
A switch 4 and a resistor 3 are connected in series between the
I have. The resistor 3 is an exciting pole of the transformer 2 when the switch 4 is turned on.
This is for suppressing the flow
The relay contacts 6 forming the bypass circuit are connected to the row.
I have. The power supply side winding of the transformer 2 has an electromagnetic coil 7.
Are connected in parallel.
Therefore, the relay contact 6 is closed. In addition,
The relay contact 6 is a make contact.
【０００７】次に動作について説明する。まず、電源投
入前の、開閉器４が開いている状態では、トランス２の
電源側にも電圧が発生していないため、電磁コイル７が
作動せずにリレー接点６は開いたままである。ここで、
開閉器４を閉じて電源を投入すると、トランス２の鉄心
の特性により過大な励磁電流が流れようとするが、抵抗
３により抑制される。このとき、トランス２の鉄心は飽
和状態であるため、トランス２と負荷５との合成インピ
ーダンスが小さく、トランス２の電源側に接続されてい
る電磁コイル７を作動させるに充分な電圧が得られな
い。すなわち、抵抗３のバイパス回路は電源投入前と同
じく開いたままである。ここで、抵抗３の値をＲ、鉄心
飽和状態のトランス２と負荷５との合成インピーダンス
をＺ0とし、電源１の電圧をＥとすると、抑制電流Ｉ
は、次式のように表される。Next, the operation will be described. First, before the power supply is turned on, when the switch 4 is open, no voltage is generated on the power supply side of the transformer 2, so that the electromagnetic coil 7 does not operate and the relay contact 6 remains open. here,
When the switch 4 is closed and the power is turned on, an excessive exciting current tends to flow due to the characteristics of the iron core of the transformer 2, but is suppressed by the resistor 3. At this time, since the core of the transformer 2 is saturated, the combined impedance of the transformer 2 and the load 5 is small, and a voltage sufficient to operate the electromagnetic coil 7 connected to the power supply side of the transformer 2 cannot be obtained. . That is, the bypass circuit of the resistor 3 remains open as before power-on. Here, assuming that the value of the resistor 3 is R, the combined impedance of the transformer 2 and the load 5 in the iron core saturation state is Z 0, and the voltage of the power supply 1 is E, the suppression current I
Is represented by the following equation.
【０００８】[0008]
【数１】Ｉ＝Ｅ／（Ｚ0＋Ｒ）## EQU1 ## I = E / (Z 0 + R)
【０００９】また、電磁コイル７が接続されているトラ
ンス２の電源側に発生する電圧Ｖ0は、次式のように表
される。The voltage V 0 generated on the power supply side of the transformer 2 to which the electromagnetic coil 7 is connected is expressed by the following equation.
【００１０】[0010]
【数２】Ｖ0＝Ｅ×Ｚ0／（Ｚ0＋Ｒ）## EQU2 ## V 0 = E × Z 0 / (Z 0 + R)
【００１１】励磁突流が発生する条件では、鉄心飽和状
態のトランス２と負荷５との合成インピーダンスＺ0が
小さく、トランス２の電源側の電圧Ｖ0は電源１の電圧
Ｅが１００Ｖに対して５０％以下となり電磁コイル７を
動作させるには不十分である。次に、電源投入から時間
が経過して、トランス２の鉄心が飽和解除し、定常状態
に近づくにつれて、トランス２のインピーダンスが大き
くなり、トランス２の電源側の電圧Ｖ0が次第に増大し
て、電磁コイル７の作動電圧に達すると、電磁コイル７
が作動してリレー接点６が閉じられる。すると、抵抗３
にバイパス回路が形成されて、電源１からの電流は抵抗
３を通ることなくトランス２へ送られるようになる。こ
こで、電磁コイル７が作動する直前にトランス２の電源
側に発生する電圧Ｖ 1は、鉄心が飽和解除し、定常状態
になりつつあるトランス２と負荷５との合成インピーダ
ンスをＺ1とすると、次式のように表される。[0011] Under the condition that the exciting jet flow occurs, the iron core is saturated.
Impedance Z of transformer 2 and load 5 in the state0But
Small, the voltage V on the power supply side of the transformer 20Is the voltage of power supply 1
E becomes 50% or less with respect to 100V.
Not enough to make it work. Next, time from power-on
Elapses, the core of the transformer 2 is released from saturation,
, The impedance of the transformer 2 increases.
And the voltage V on the power supply side of the transformer 20Gradually increased
When the operating voltage of the electromagnetic coil 7 is reached,
Operates and the relay contact 6 is closed. Then resistance 3
A bypass circuit is formed in the
3 is sent to the transformer 2 without passing through the transformer. This
Here, immediately before the electromagnetic coil 7 operates, the power supply of the transformer 2 is turned on.
V generated on the side 1Indicates that the iron core is de-saturated and
Combined Impedance of Transformer 2 and Load 5
To Z1Then, it is expressed by the following equation.
【００１２】[0012]
【数３】Ｖ1＝Ｅ×Ｚ1／（Ｚ1＋Ｒ）## EQU3 ## V 1 = E × Z 1 / (Z 1 + R)
【００１３】通常、Ｚ1》Ｒのためトランス２の電源側
の電圧Ｖ1は電源１の電圧Ｅが１００Ｖに対しほぼ１０
０％となり電磁コイル７を作動させる。この電圧Ｖ1に
より、電磁コイル７が作動してリレー接点６が閉じられ
ると、電磁コイル７へ加えられる電圧はさらに上昇し、
ほぼ電源１の電圧Ｅと等しくなる。以後、開閉器４が切
られるまで、抵抗３はバイパスされたままの定常状態が
保たれる。このように、本発明の実施形態では、リレー
からなる簡単な回路を用いて、トランス２の電源側に直
列接続されている励磁突流抑制用の抵抗３が、電源投入
時の最初だけ作動するようにしたものである。Normally, since Z 1 >> R, the voltage V 1 on the power supply side of the transformer 2 is approximately 10 V when the voltage E of the power supply 1 is 100 V.
It becomes 0%, and the electromagnetic coil 7 is operated. When this voltage V 1 activates the electromagnetic coil 7 and closes the relay contact 6, the voltage applied to the electromagnetic coil 7 further increases,
It becomes almost equal to the voltage E of the power supply 1. Thereafter, until the switch 4 is turned off, the resistor 3 is kept in a steady state in a state of being bypassed. As described above, in the embodiment of the present invention, using the simple circuit including the relay, the exciting sudden current suppressing resistor 3 connected in series to the power supply side of the transformer 2 operates only at the first power-on. It was made.
【００１４】 図２は、本発明の実施形態を示す回路図
である。図において、商用電源１とトランス２の電源側
巻線の一端との間に、開閉器４を介して第１の抵抗３と
第２の抵抗８とが直列に接続されている。また、第１の
抵抗３に並列にリレー接点６を接続して第１のバイパス
回路が構成されると共に、第２の抵抗８に並列にリレー
接点９を接続して第２のバイパス回路が構成される。更
に、第１の抵抗３と第２の抵抗８との相互の接続点と、
トランス２の電源側巻線の他端との間に、両リレー接点
６，９開閉用の電磁コイル７が接続されている。 FIG. 2 is a circuit diagram showing an embodiment of the present invention.
It is. In the figure, the commercial power supply 1 and the power supply side of the transformer 2
The first resistor 3 is connected to one end of the winding via a switch 4.
The second resistor 8 is connected in series. Also, the first
A first bypass by connecting a relay contact 6 in parallel with the resistor 3
A circuit is configured and a relay is connected in parallel with the second resistor 8.
The contact 9 is connected to form a second bypass circuit. Change
A connection point between the first resistor 3 and the second resistor 8;
Two relay contacts between the other end of the power supply side winding of transformer 2
Electromagnetic coils 7 for opening and closing 6, 9 are connected.
【００１５】 この実施形態では、前記の図１によって
説明した動作原理により、開閉器４を閉じて電源を投入
した直後には、トランス２に流れようとする励磁突流を
第１の抵抗３及び第２の抵抗８により抑制する。このと
き、トランス２の鉄心は飽和状態であり、トランス２と
負荷５との合成インピーダンスは小さく、トランス２の
電源側巻線の両端電圧が小さいため、電磁コイル７を作
動させるために十分な電圧は発生していない。よって両
リレー接点６，９は開いたままである。次に、電源投入
から時間が経過してトランス２の鉄心の飽和が解除さ
れ、定常状態に近づくと、トランス２のインピーダンス
が大きくなり、電源側巻線の両端電圧が電磁コイル７の
作動電圧に達すると、電磁コイル７への通電により両リ
レー接点６，９が閉じ、第１及び第２のバイパス回路が
形成される。このため、定常状態では電源１からの電流
が第１の抵抗３及び第２の抵抗８を通らずに両リレー接
点６，９を介してトランス２の電源側巻線に流れること
になり、抵抗による損失、発熱が防止されることとな
る。特に本実施形態では、第１の抵抗３及び第２の抵抗
８の各抵抗値を変化させてその抵抗値比を変えること
で、電磁コイル７に印加される電圧が作動電圧に達する
タイミングを調整することができ、トランスのインピー
ダンス等の実際の回路条件に応じた最適なタイミングで
電流をバイパスさせることができる。 In this embodiment, FIG.
According to the operation principle described, the switch 4 is closed and the power is turned on.
Immediately after the
It is suppressed by the first resistor 3 and the second resistor 8. This and
The transformer 2 core is saturated,
The combined impedance with the load 5 is small,
Since the voltage at both ends of the power supply side winding is small, the electromagnetic coil 7
There is not enough voltage to operate. So both
Relay contacts 6, 9 remain open. Next, turn on the power
After a while, the saturation of the transformer 2 core is released
When approaching the steady state, the impedance of the transformer 2
And the voltage across the power supply winding becomes
When the operating voltage is reached, the two coils
Ray contacts 6 and 9 are closed and the first and second bypass circuits are
It is formed. Therefore, in the steady state, the current from the power supply 1
Is connected to both relays without passing through the first resistor 3 and the second resistor 8.
Flow to the power supply side winding of transformer 2 through points 6 and 9
And loss and heat generation due to resistance are prevented.
You. Particularly, in the present embodiment, the first resistor 3 and the second resistor
8 to change the resistance value and change the resistance ratio
The voltage applied to the electromagnetic coil 7 reaches the operating voltage
The timing can be adjusted and the impedance of the transformer
At the optimal timing according to the actual circuit conditions such as dance
The current can be bypassed.
【００１６】[0016]
【発明の効果】以上のように本発明では、商用電源とト
ランスの電源側巻線の一端との間に、開閉器を介して第
１の抵抗と第２の抵抗とを直列に接続し、第１の抵抗に
並列にリレー接点を接続して第１のバイパス回路を構成
すると共に、第２の抵抗に並列にリレー接点を接続して
第２のバイパス回路を構成し、第１の抵抗と第２の抵抗
との相互の接続点と、前記電源側巻線の他端との間に、
前記両リレー接点開閉用の電磁コイルを接続し、前記開
閉器の投入直後には前記第１の抵抗及び第２の抵抗によ
りトランスに対する励磁突流を抑制し、その後に上昇し
た前記電源側巻線の両端電圧により前記電磁コイルを作
動させて前記両リレー接点を閉じるようにしたものであ
る。このため、定常状態における抵抗損失、電力消費等
を解消すると共に、第１，第２の抵抗の抵抗値比を変え
ることで最適なタイミングでバイパス回路を形成するこ
とができ、実際の回路に対する融通性や汎用性を高める
ことができる。 As described above , according to the present invention, the commercial power supply
Between the lance and one end of the power supply side winding via a switch.
The first resistor and the second resistor are connected in series, and the first resistor is connected to the first resistor.
Connect the relay contacts in parallel to form the first bypass circuit
And connect the relay contact in parallel with the second resistor
Forming a second bypass circuit, the first resistor and the second resistor;
Between the mutual connection point and the other end of the power supply side winding,
Connect the electromagnetic coils for opening and closing the two relay contacts,
Immediately after closing the switch, the first resistor and the second resistor are used.
Suppresses the exciting flow to the transformer, and then rises
The electromagnetic coil is created by the voltage between both ends of the power supply side winding.
To close both relay contacts.
You. For this reason, resistance loss, power consumption, etc. in the steady state
And changing the resistance value ratio of the first and second resistors.
To form a bypass circuit at the optimal timing.
To increase the flexibility and versatility of actual circuits
be able to.
【図１】 本発明の原理を説明するための回路図であ
る。FIG. 1 is a circuit diagram for explaining the principle of the present invention.
【図２】 本発明の実施形態を示す回路図である。FIG. 2 is a circuit diagram showing an embodiment of the present invention.
【図３】 従来例を示す回路図である。FIG. 3 is a circuit diagram showing a conventional example.
１ 商用電源 ２ トランス ３，８ 抵抗 ４ 開閉器 ５ 負荷 ６，９ リレー接点 ７ 電磁コイルDESCRIPTION OF SYMBOLS 1 Commercial power supply 2 Transformer 3 and 8 resistance 4 Switch 5 Load 6 and 9 Relay contact 7 Electromagnetic coil
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平３−23823（ＪＰ，Ａ) 特開 昭57−20125（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H02H 9/02 G05F 1/10 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-23823 (JP, A) JP-A-57-20125 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) H02H 9/02 G05F 1/10
Claims (1)
の間に、開閉器を介して第１の抵抗と第２の抵抗とを直
列に接続し、 第１の抵抗に並列にリレー接点を接続して第１のバイパ
ス回路を構成すると共に、第２の抵抗に並列にリレー接
点を接続して第２のバイパス回路を構成し、 第１の抵抗と第２の抵抗との相互の接続点と、前記電源
側巻線の他端との間に、前記両リレー接点開閉用の電磁
コイルを接続し、 前記開閉器の投入直後には前記第１の抵抗及び第２の抵
抗によりトランスに対する励磁突流を抑制し、その後に
上昇した前記電源側巻線の両端電圧により前記電磁コイ
ルを作動させて前記両リレー接点を閉じる ことを特徴と
するトランスの励磁突流抑制回路。1. A commercial power supply and one end of a power supply side winding of a transformer.
Between the first resistor and the second resistor via a switch.
And a relay contact connected in parallel with the first resistor to form a first bypass.
And a relay connected in parallel with the second resistor.
A second bypass circuit is formed by connecting points, a mutual connection point between a first resistor and a second resistor, and the power supply
Electromagnetic for opening and closing both relay contacts between the other end of the side winding
A coil is connected, and immediately after the switch is turned on, the first resistor and the second resistor are connected.
Suppress the exciting current to the transformer by the resistance, and then
The voltage of the electromagnetic coil
A transformer exciting current suppression circuit characterized in that the relay contacts are closed by operating the relay .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21340296A JP3236223B2 (en) | 1996-08-13 | 1996-08-13 | Transformer excitation surge suppression circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21340296A JP3236223B2 (en) | 1996-08-13 | 1996-08-13 | Transformer excitation surge suppression circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1066253A JPH1066253A (en) | 1998-03-06 |
| JP3236223B2 true JP3236223B2 (en) | 2001-12-10 |
Family
ID=16638634
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21340296A Expired - Fee Related JP3236223B2 (en) | 1996-08-13 | 1996-08-13 | Transformer excitation surge suppression circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3236223B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10629637B2 (en) | 2001-11-30 | 2020-04-21 | Semiconductor Energy Laboratory Co., Ltd. | Vehicle, display device and manufacturing method for a semiconductor device |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE514817C2 (en) | 1999-10-05 | 2001-04-30 | Abb Ab | Apparatus for voltage setting of a rigid inverter and transformer equipment for connection to such a device |
| KR100861283B1 (en) * | 2007-03-31 | 2008-10-01 | 엘지전자 주식회사 | Refrigerator and operating method for same |
-
1996
- 1996-08-13 JP JP21340296A patent/JP3236223B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10629637B2 (en) | 2001-11-30 | 2020-04-21 | Semiconductor Energy Laboratory Co., Ltd. | Vehicle, display device and manufacturing method for a semiconductor device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH1066253A (en) | 1998-03-06 |
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