WO2004036715A1 - Electric power savings device used saturable reactor - Google Patents

Electric power savings device used saturable reactor Download PDF

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Publication number
WO2004036715A1
WO2004036715A1 PCT/KR2002/001922 KR0201922W WO2004036715A1 WO 2004036715 A1 WO2004036715 A1 WO 2004036715A1 KR 0201922 W KR0201922 W KR 0201922W WO 2004036715 A1 WO2004036715 A1 WO 2004036715A1
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WO
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Prior art keywords
load
winding wire
current
scr
saturable reactor
Prior art date
Application number
PCT/KR2002/001922
Other languages
French (fr)
Inventor
In-Cheon Oh
Young-Ha Cho
Original Assignee
Dongah Tech Inc.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Dongah Tech Inc. filed Critical Dongah Tech Inc.
Priority to PCT/KR2002/001922 priority Critical patent/WO2004036715A1/en
Priority to AU2002368291A priority patent/AU2002368291A1/en
Publication of WO2004036715A1 publication Critical patent/WO2004036715A1/en

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
    • H02H9/021—Current limitation using saturable reactors

Definitions

  • the present invention relates to a power saving device, and more particularly, to a saturable reactor type power saving device that can provide a load unit with a necessary electric power stably by judging necessary current of the load unit and a state of an input power source using the saturable reactor, thereby a voltage drop effect and a power factor improvement can be obtained.
  • forming a tap in a single winding wire type transformer i.e., an autotransformer
  • dropping an input voltage with a switch or a relay can save the electric power.
  • dropping a load unit voltage using a voltage drop variation induced at a secondary coil of the mutual inductance reactor can save the electric power.
  • controlling an inductance of a primary coil and then dropping a voltage of an electric power source can also save the electric power. That is, the inductance of the primary coil can be controlled by forming a tap in the second coil of a double winding wire type transformer and performing a negative phase sequence control with a relay.
  • the load unit is an electric light
  • the electric light frequently flickers owing to frequent actions of the relay when the voltage of the electric power source changes.
  • the electric power is cut off in a moment and an excessive over-current flows in the load unit such as an air conditioner and a refrigerator each time the relay acts, thereby a life span of the product is reduced and a noise occurs owing to the frequent action of the relay.
  • the present invention is directed to a saturable reactor type power saving device that substantially obviates one or more of problems due to limitations and disadvantages of the related art.
  • An object of the present invention is to provide a saturable reactor type power saving device that can prevent an instant power off phenomenon without a relay by preventing over- current caused by a load change of the load unit.
  • Another object of the present invention is to provide a saturable reactor type power saving device that can provide a safety by preventing an occurrence of a high voltage during an induction or a voltage change at an excitation coil.
  • Another object of the present invention is to provide a saturable reactor type power saving device that can protect an electric goods from an overcurrent in a load unit by controlling the current linearly.
  • Another object of the present invention is to provide a saturable reactor type power saving device that is free of noise owing to a mechanical contact action of a relay.
  • a saturable reactor type power saving device comprises a saturable reactor having a magnetic core, a load winding wire and a control winding wire, the load winding wire connected to an electric power source and a load unit, the control winding wire connected to SCR; a current detector for detecting a current flowing from the load winding wire to the load unit; and a control unit connected to the SCR, the current detector and an input device, the input device used for setting a reference voltage for the control unit, the control unit receiving an information on a current of the load unit detected by the current detector and transmitting a control signal to the SCR; wherein, if the control unit generates and transmits the control signal to the SCR to drive the SCR after comparing the detected current with the preset reference voltage, voltage of the load winding wire becomes changeable according to a drive of the SCR and thus an electric power of the load unit can be controlled.
  • the saturable reactor type power saving device further comprises a bypass switch connected to the control unit and the load winding wire, the bypass switch driven by a control signal of the control unit when voltage of the load unit is lower than the reference voltage.
  • FIG. 1 is a circuit diagram of a saturable reactor type power saving device according to the present invention
  • FIG. 2A is a driving circuit diagram of a general saturable reactor adopted in the present invention
  • FIG. 2B is a magnetic flux diagram of a general saturable reactor adopted in the present invention
  • FIG. 3 is a circuit diagram for an explanation of an operation of a saturable reactor type power saving device according to the present invention.
  • FIG. 4 is a graph illustrating a current of a saturable reactor type power saving device according to the present invention.
  • FIG. 1 is a circuit diagram of a saturable reactor type power saving device according to the present invention.
  • FIG. 2A is a driving circuit diagram of a general saturable reactor adopted in the present invention and
  • FIG. 2B is a magnetic flux diagram of a general saturable reactor adopted in the present invention.
  • FIG. 3 is a circuit diagram for an explanation of an operation of a saturable reactor type power saving device according to the present invention and
  • FIG. 4 is a graph illustrating a current of a saturable reactor type power saving device according to the present invention.
  • the present invention mainly comprises a saturable reactor 20, a current detector 30 and a control unit 50.
  • the present invention further comprises a bypass switch 53 connected to a load winding wire 21 of the saturable reactor 20.
  • the saturable reactor 20 is for changing a magnitude of an AC current using a DC control current.
  • the saturable reactor 20 comprises a magnetic core having a saturation property and shaped like a rectangular loop and two winding wire wrapped around the magnetic core.
  • the saturable reactor changes a current of the load winding wire by sending a DC control current to the control winding wire using a non-linearity of the magnetic core.
  • a property of the saturable reactor 20 adopted for the present invention will be described hereinafter with reference to FIG. 2.
  • FIG. 2A is a circuit diagram of the saturable reactor according to the present invention and FIG. 2B is a magnetic flux graph of the saturable reactor according to the present invention.
  • the saturable reactor 20 includes the control winding wire 22 and the load winding wire 21. If a load and an AC current is applied to the load winding wire, a magnetic flux ( ⁇ ) is generated in the magnetic core, i.e., an iron core, of the saturable reactor 20. At this time, if a DC control current is input to the control winding wire, a constant magnetic flux ( ⁇ c ) is generated and thus a total magnetic flux value ( ⁇ j ) of the iron core can be expressed as follows.
  • a saturation magnetic flux of the iron core is defined as ⁇ s .
  • the total magnetic flux value ⁇ j becomes equal to the saturation magnetic flux ( ⁇ s )
  • the total magnetic flux ( ⁇ j ) of the iron core can not increase any more and a negligible excitation current is generated in the saturable reactor 20.
  • an electric power source 10 is connected to one end of the load winding wire 21 and the load unit is connected to the other end of the load winding wire 21.
  • a SCR (silicon controlled rectifier) 52 driven by a control signal of the control unit 50 is connected to the control winding wire 22.
  • a current detector 30 is connected between the saturable reactor 20 and the load unit 40 so that the current detector 30 detects a current flowing in the load unit 40 and then transmits information on the detected current to the control unit 50.
  • An input device 51 connected to the control unit 50 sets up a magnitude of reference voltage and current to be inputted to the load unit 40 as a control command in the control unit 50.
  • a logic circuit for comparing the current detected at the current detector 30 with the preset value of the voltage and current is embedded in the control unit.
  • the preset reference voltage and current may be rated voltage and current.
  • the control unit 50 compares the current of the load unit 40 detected by the current detector 30 with the rated current and voltage. Because the load of the load unit 40 is usually a load for a use in the house, a magnitude of the load is changeable. If the load abruptly changes during a start of the load unit 40 as in the case of a motor, the amount of the current flowing in the load unit is changed. If the amount of current detected by the current detector 30 exceeds the rated current, the control unit 50 increases voltage (N.) of the load winding wire 21 by driving the SCR 52.
  • a bypass switch 53 is connected to the load winding wire 21 and the control unit 50.
  • the bypass switch 53 is driven on and off by the control signal of the control unit 50 if the voltage of the load unit 40 becomes lower than the preset value deciding by the current detected by the current detector 30. If a normal operation voltage range of the load unit 40 is 220N + 6%, voltage value ranging from 207 to 233 is allowed for the operation of the load unit 40.
  • the voltage (N_) of the load winding wire 21 must be below zero when an input voltage of the load unit 40 is smaller than a minimum allowable voltage value of 207 N Therefore, at this time, a power saving control of the saturable reactor 20 is unnecessary and thus a bypass switch 53 turns on.
  • the load unit 40 when the load unit 40 requires a high current owing to an abrupt load change or an overload, for example, as in a case of a start of the motor, the current of the load winding wire 21 becomes increased resulting in an abrupt increase of the voltage (V of the load winding wire 21. If the voltage (NJ of the load winding wire 21 is increased, an input voltage (N L ) of the load unit 40 decreases correspondingly so that it fails to satisfy the necessary electric power of the load unit 40. In this case, a power saving function of a saturable reactor 20 is also unnecessary.
  • the control unit 50 compares the current detected by the current detector 30 with the preset reference current value and then generates the control signal for driving the bypass switch 53 if the saturable reactor 20 cannot satisfy the necessary electric power for the load unit 40 Once the bypass switch 53 is turned on, the electric power is supplied directly from the electric power source 10 to the load unit 40.
  • the present invention provides a saturable reactor type power saving device that can save power consumption by monitoring a change of the current of the load unit 40 and then driving the control winding wire 22 by the control signal of the control unit 50.
  • the present invention also provides an saturable reactor type power saving device having an improved response property that connects the electric power source to the load unit in series under certain input electric power and load conditions of the load unit 40.
  • an over-current in a load unit can be lowered linearly by controlling voltage of a loading winding wire changeably.
  • the change of the voltage of the load winding wire can be done by controlling current of a control winding wire by a SCR without mechanical contact of a relay. Accordingly, because the over-current can be lowered linearly in the load unit, an instant power off phenomenon can be prevented at the load unit.
  • a safe saturable reactor type power saving device that is free of a possibility of a generation of a high voltage in the control winding wire can be provided.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Electrical Variables (AREA)

Abstract

In a saturable reactor type power saving device for reducing a power consumption by controlling an AC current supplied to a load unit, the saturable reactor type power saving device, comprises a saturable reactor having a magnetic core, a load winding wire and a control winding wire, the load winding wire connected to an electric power source and a load unit, the control winding wire connected to SCR; a current detector for detecting a current flowing from the load winding wire to the load unit; and a control unit connected to the SCR, the current detector and an input device, the input device used for setting a reference voltage for the control unit, the control unit receiving an information on a current of the load unit detected by the current detector and transmitting a control signal to the SCR; wherein, if the control unit generates and transmits the control signal to the SCR to drive the SCR after comparing the detected current with the preset reference voltage, voltage of the load winding wire becomes changeable according to a drive of the SCR and thus an electric power of the load unit can be controlled.

Description

ELECTRIC POWER SAVINGS DEVICE USED SATURABLE REACTOR
TECHNICAL FIELD
The present invention relates to a power saving device, and more particularly, to a saturable reactor type power saving device that can provide a load unit with a necessary electric power stably by judging necessary current of the load unit and a state of an input power source using the saturable reactor, thereby a voltage drop effect and a power factor improvement can be obtained.
BACKGROUND ART
Generally, many different power saving devices have been suggested in the field to save an electric power. That is, according to one of the related art, forming a tap in a single winding wire type transformer, i.e., an autotransformer, and dropping an input voltage with a switch or a relay can save the electric power. According to other related art, dropping a load unit voltage using a voltage drop variation induced at a secondary coil of the mutual inductance reactor can save the electric power. According to other related art, controlling an inductance of a primary coil and then dropping a voltage of an electric power source can also save the electric power. That is, the inductance of the primary coil can be controlled by forming a tap in the second coil of a double winding wire type transformer and performing a negative phase sequence control with a relay.
However, according to the related arts, there arise problems as follows. If the load unit is an electric light, the electric light frequently flickers owing to frequent actions of the relay when the voltage of the electric power source changes. Besides, the electric power is cut off in a moment and an excessive over-current flows in the load unit such as an air conditioner and a refrigerator each time the relay acts, thereby a life span of the product is reduced and a noise occurs owing to the frequent action of the relay.
In addition, according to a typical double winding wire type transformer, several thousands voltage may be induced when voltage is induced at an excitation coil and thereby a safety problem may occur. Moreover, because a malfunction of the transformer may occur during an auto-change of the voltage, a short of the circuit may occur owing to an instant simultaneous contact that may cause an accident. DISCLOSURE OF INVENTION
Accordingly, the present invention is directed to a saturable reactor type power saving device that substantially obviates one or more of problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a saturable reactor type power saving device that can prevent an instant power off phenomenon without a relay by preventing over- current caused by a load change of the load unit.
Another object of the present invention is to provide a saturable reactor type power saving device that can provide a safety by preventing an occurrence of a high voltage during an induction or a voltage change at an excitation coil.
Another object of the present invention is to provide a saturable reactor type power saving device that can protect an electric goods from an overcurrent in a load unit by controlling the current linearly.
Another object of the present invention is to provide a saturable reactor type power saving device that is free of noise owing to a mechanical contact action of a relay.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a saturable reactor type power saving device according to the present invention comprises a saturable reactor having a magnetic core, a load winding wire and a control winding wire, the load winding wire connected to an electric power source and a load unit, the control winding wire connected to SCR; a current detector for detecting a current flowing from the load winding wire to the load unit; and a control unit connected to the SCR, the current detector and an input device, the input device used for setting a reference voltage for the control unit, the control unit receiving an information on a current of the load unit detected by the current detector and transmitting a control signal to the SCR; wherein, if the control unit generates and transmits the control signal to the SCR to drive the SCR after comparing the detected current with the preset reference voltage, voltage of the load winding wire becomes changeable according to a drive of the SCR and thus an electric power of the load unit can be controlled.
In the above, the saturable reactor type power saving device further comprises a bypass switch connected to the control unit and the load winding wire, the bypass switch driven by a control signal of the control unit when voltage of the load unit is lower than the reference voltage. BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a circuit diagram of a saturable reactor type power saving device according to the present invention;
FIG. 2A is a driving circuit diagram of a general saturable reactor adopted in the present invention; FIG. 2B is a magnetic flux diagram of a general saturable reactor adopted in the present invention; FIG. 3 is a circuit diagram for an explanation of an operation of a saturable reactor type power saving device according to the present invention; and
FIG. 4 is a graph illustrating a current of a saturable reactor type power saving device according to the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
Reference will now be made in detail to the preferred embodiment of the present invention, which is illustrated in the accompanying drawings.
FIG. 1 is a circuit diagram of a saturable reactor type power saving device according to the present invention. FIG. 2A is a driving circuit diagram of a general saturable reactor adopted in the present invention and FIG. 2B is a magnetic flux diagram of a general saturable reactor adopted in the present invention. FIG. 3 is a circuit diagram for an explanation of an operation of a saturable reactor type power saving device according to the present invention and FIG. 4 is a graph illustrating a current of a saturable reactor type power saving device according to the present invention.
In FIG. 1, the present invention mainly comprises a saturable reactor 20, a current detector 30 and a control unit 50. The present invention further comprises a bypass switch 53 connected to a load winding wire 21 of the saturable reactor 20.
In FIG. 2A, the saturable reactor 20, called also as a transductor, is for changing a magnitude of an AC current using a DC control current. The saturable reactor 20 comprises a magnetic core having a saturation property and shaped like a rectangular loop and two winding wire wrapped around the magnetic core. The saturable reactor changes a current of the load winding wire by sending a DC control current to the control winding wire using a non-linearity of the magnetic core. A property of the saturable reactor 20 adopted for the present invention will be described hereinafter with reference to FIG. 2. FIG. 2A is a circuit diagram of the saturable reactor according to the present invention and FIG. 2B is a magnetic flux graph of the saturable reactor according to the present invention.
As shown in the figures, the saturable reactor 20 includes the control winding wire 22 and the load winding wire 21. If a load and an AC current is applied to the load winding wire, a magnetic flux (φ) is generated in the magnetic core, i.e., an iron core, of the saturable reactor 20. At this time, if a DC control current is input to the control winding wire, a constant magnetic flux (φc) is generated and thus a total magnetic flux value (φj) of the iron core can be expressed as follows.
Figure imgf000005_0001
Accordingly, a base line of the magnetic flux is lifted from "O-O" to "O O 'owing to the constant magnetic flux (φ0) as shown in FIG. 2B. A saturation magnetic flux of the iron core is defined as φs. As the iron core becomes saturated and thus the total magnetic flux value φj becomes equal to the saturation magnetic flux (φs), the total magnetic flux (φj) of the iron core can not increase any more and a negligible excitation current is generated in the saturable reactor 20.
As shown in figures, an electric power source 10 is connected to one end of the load winding wire 21 and the load unit is connected to the other end of the load winding wire 21. A SCR (silicon controlled rectifier) 52 driven by a control signal of the control unit 50 is connected to the control winding wire 22. A current detector 30 is connected between the saturable reactor 20 and the load unit 40 so that the current detector 30 detects a current flowing in the load unit 40 and then transmits information on the detected current to the control unit 50. An input device 51 connected to the control unit 50 sets up a magnitude of reference voltage and current to be inputted to the load unit 40 as a control command in the control unit 50. A logic circuit for comparing the current detected at the current detector 30 with the preset value of the voltage and current is embedded in the control unit. The preset reference voltage and current may be rated voltage and current.
If the rated current and voltage are set by the input device 51, the control unit 50 compares the current of the load unit 40 detected by the current detector 30 with the rated current and voltage. Because the load of the load unit 40 is usually a load for a use in the house, a magnitude of the load is changeable. If the load abruptly changes during a start of the load unit 40 as in the case of a motor, the amount of the current flowing in the load unit is changed. If the amount of current detected by the current detector 30 exceeds the rated current, the control unit 50 increases voltage (N.) of the load winding wire 21 by driving the SCR 52. Accordingly, voltage (NL) of the load unit 40 is lowered and thus the current flowing into the load unit 40 is lowered from IL1 to IL2 as shown in FIG. 4, thereby an over-current can be controlled. A bypass switch 53 is connected to the load winding wire 21 and the control unit 50. The bypass switch 53 is driven on and off by the control signal of the control unit 50 if the voltage of the load unit 40 becomes lower than the preset value deciding by the current detected by the current detector 30. If a normal operation voltage range of the load unit 40 is 220N + 6%, voltage value ranging from 207 to 233 is allowed for the operation of the load unit 40. The voltage (N_) of the load winding wire 21 must be below zero when an input voltage of the load unit 40 is smaller than a minimum allowable voltage value of 207 N Therefore, at this time, a power saving control of the saturable reactor 20 is unnecessary and thus a bypass switch 53 turns on.
Meanwhile, when the load unit 40 requires a high current owing to an abrupt load change or an overload, for example, as in a case of a start of the motor, the current of the load winding wire 21 becomes increased resulting in an abrupt increase of the voltage (V of the load winding wire 21. If the voltage (NJ of the load winding wire 21 is increased, an input voltage (NL) of the load unit 40 decreases correspondingly so that it fails to satisfy the necessary electric power of the load unit 40. In this case, a power saving function of a saturable reactor 20 is also unnecessary.
Therefore, according to the present invention, the control unit 50 compares the current detected by the current detector 30 with the preset reference current value and then generates the control signal for driving the bypass switch 53 if the saturable reactor 20 cannot satisfy the necessary electric power for the load unit 40 Once the bypass switch 53 is turned on, the electric power is supplied directly from the electric power source 10 to the load unit 40.
As described hereto, the present invention provides a saturable reactor type power saving device that can save power consumption by monitoring a change of the current of the load unit 40 and then driving the control winding wire 22 by the control signal of the control unit 50. The present invention also provides an saturable reactor type power saving device having an improved response property that connects the electric power source to the load unit in series under certain input electric power and load conditions of the load unit 40.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
INDUSTRIAL APPLICABILITY
According to the present invention, an over-current in a load unit can be lowered linearly by controlling voltage of a loading winding wire changeably.
The change of the voltage of the load winding wire can be done by controlling current of a control winding wire by a SCR without mechanical contact of a relay. Accordingly, because the over-current can be lowered linearly in the load unit, an instant power off phenomenon can be prevented at the load unit.
According to the present invention, because only negligible excitation current flows in the control winding wire when an induced current is formed in the control winding wire, a safe saturable reactor type power saving device that is free of a possibility of a generation of a high voltage in the control winding wire can be provided.
In addition, according to the present invention, electric goods can be protected from a possibility of an over-current and a noise usually caused by a mechanical contact action of a relay can be avoided. Besides, though there occurs an under-voltage phenomenon in the load unit, a required voltage can be supplied to the load unit.

Claims

1. In a saturable reactor type power saving device for reducing a power consumption by controlling an AC current supplied to a load unit, the saturable reactor type power saving device, comprising: a saturable reactor having a magnetic core, a load winding wire and a control winding wire, the load winding wire connected to an electric power source and a load unit, the control winding wire connected to SCR; a current detector for detecting a current flowing from the load winding wire to the load unit; and a control unit connected to the SCR, the current detector and an input device, the input device used for setting a reference voltage for the control unit, the control unit receiving an information on a current of the load unit detected by the current detector and transmitting a control signal to the SCR; wherein, if the control unit generates and transmits the control signal to the SCR to drive the SCR after comparing the detected current with the preset reference voltage, voltage of the load winding wire becomes changeable according to a drive of the SCR and thus an electric power of the load unit can be controlled.
2. The device according to claim 1, further comprising a bypass switch connected to the control unit and the load winding wire, the bypass switch driven by a control signal of the control unit when voltage of the load unit is lower than the reference voltage.
PCT/KR2002/001922 2002-10-15 2002-10-15 Electric power savings device used saturable reactor WO2004036715A1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008125022A1 (en) * 2007-04-17 2008-10-23 Innopower Superconductor Cable Co., Ltd Core-saturated superconductive fault current limiter and control method of the fault current limiter
CN102664393A (en) * 2012-05-18 2012-09-12 广东电网公司电力科学研究院 Short-circuit current limiting device
CN106385018A (en) * 2016-10-27 2017-02-08 华中科技大学 Shortcircuit fault current limiter
WO2019158180A1 (en) * 2018-02-13 2019-08-22 Siemens Aktiengesellschaft Device for limiting electrical current

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JPS5879561A (en) * 1981-11-06 1983-05-13 Sumitomo Metal Ind Ltd Electrostatic precipitator
US4602166A (en) * 1983-05-19 1986-07-22 Steve Smith Transformer driving network with primary current limiting means
JPS6412860A (en) * 1987-07-02 1989-01-17 Shindengen Electric Mfg Switching regulator
JPH01264557A (en) * 1988-04-15 1989-10-20 Canon Inc Linear motor

Patent Citations (4)

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Publication number Priority date Publication date Assignee Title
JPS5879561A (en) * 1981-11-06 1983-05-13 Sumitomo Metal Ind Ltd Electrostatic precipitator
US4602166A (en) * 1983-05-19 1986-07-22 Steve Smith Transformer driving network with primary current limiting means
JPS6412860A (en) * 1987-07-02 1989-01-17 Shindengen Electric Mfg Switching regulator
JPH01264557A (en) * 1988-04-15 1989-10-20 Canon Inc Linear motor

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008125022A1 (en) * 2007-04-17 2008-10-23 Innopower Superconductor Cable Co., Ltd Core-saturated superconductive fault current limiter and control method of the fault current limiter
US8582255B2 (en) 2007-04-17 2013-11-12 Innopower Superconductor Cable Co., Ltd. Core-saturated superconductive fault current limiter and control method of the fault current limiter
CN102664393A (en) * 2012-05-18 2012-09-12 广东电网公司电力科学研究院 Short-circuit current limiting device
CN102664393B (en) * 2012-05-18 2015-08-12 广东电网公司电力科学研究院 Short circuit current current-limiting apparatus
CN106385018A (en) * 2016-10-27 2017-02-08 华中科技大学 Shortcircuit fault current limiter
CN106385018B (en) * 2016-10-27 2019-04-23 华中科技大学 A kind of short-circuit fault current limiter
WO2019158180A1 (en) * 2018-02-13 2019-08-22 Siemens Aktiengesellschaft Device for limiting electrical current

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