• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.4
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• pp.340-348
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• 2006

This paper proposes an inrush current control technique of matching transformer for configuration of dynamic voltage restorer(DVR). The DVR system consist of PWM inverter to inject arbitrary voltage, LC low pass filter as harmonic eliminator and matching transformer for isolation. However, the matching transformer has an excess of inrush current by magnetic flux saturation in the core. Due to this inrush current, the rating of matching transformers is double for needed nominal rating for protection of DVR. Therefore, in this paper, the modeling method of magnetic flux saturation is used to analyze a magnitude of inrush current, and additional current controller is used for PWM inverter output regulation. Simulation and experimental results are provided to demonstrate the validity of the proposed control method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.5
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• pp.61-67
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• 2001

Magnetic flux saturation dependent on phase of initial input power to high voltage transformer used in Micro wave oven. To limit inrush current high voltage transformer the relay contact should be ˝ON˝ when the lowest point of input voltage phase. The improved circuit is form compensating interrupt signal Micom input so the relay contact can be ˝ON˝ when the inrush current is lower. Test results are presented that improved circuit satisfies the limit 50[A] of requirement for input voltage variation mode. And the result verified by statistical method.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.11 no.4
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• pp.100-108
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• 1997

A combined buck and boost push-pull quantum series resonant rectifier(PPQSRR) is newly proposed to achieve a power factor correction without start-up inrush current. Based on the developed dynamic modeling of the proposed rectifier, an inrush current elimination control technique is proposed and the usefullness of the proposed rectifier and control method are verified by computer simulation and experimental results. With the proposed control method, a high power factor and wide range of output voltage can be obtained.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2232-2234
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• 2005

배전 계통에서는 전동기의 시동 전류, 변압기의 여자돌입전류, 콘덴서의 고주파 과도 돌입전류 등의 과전류가 흐르므로, 회로 보호용 한류 퓨즈가 엘리먼트의 피로나 열화 등에 의해, 예기치 못한 용단이 발생한다. 이 경우 고장을 미연에 방지하기 위해, 한류 퓨즈의 신뢰성을 보다 향상시키기 위해서는 제품 특성의 균일성을 확보함으로서 그 사용 실태에 대응해서 적절히 교환하는 것이 필요하다.

• 전기의세계
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• v.14 no.5
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• pp.8-14
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• 1965

Because of the flat slope of the magnetic characteristic curves at high saturation, the transformer inrush current peakes may assume an extreme magnitude. Even though such is rarely any danger to the transformer itself, the currents can cause serious problems in associated apparatus. This paper has analyzed various limiting factors of excess inrush currents, and then has suggested how to determine the frequency of encountering the inrush current peaks higher than an arbitrarily chosen value by deriving the probability equations of inrush current occurrence.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.469-470
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• 2015

본 논문에서는 PFC(Power Factor Correction) 컨버터의 초기 구동시 발생하는 돌입전류 문제 및 스위치의 고장을 진단하는 방법에 대해 기술한다. PFC 컨버터는 초기 구동시 출력단의 대용량 커패시터에 의해 높은 돌입전류가 발생하여 시스템 손상 및 전력 계통의 품질과 고조파를 발생하는 문제점을 갖고 있다. 따라서 본 논문에서는 저항과 스위치를 이용한 PFC 컨버터의 초기 돌입 전류 제한 및 안정적인 동작을 위한 스위치 고장진단 방법을 제안하고, 시뮬레이션을 통해 타당성을 입증하였다.

• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.306-307
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• 2017

본 논문에서는 태양광모듈과 전력변환장치간의 접속장치로 사용된 전력용 반도체 스위칭 소자의 소프트 스타팅 기법을 통해 초기 돌입전류를 저감하는 알고리즘을 제안하고자 한다. 태양광 모듈의 경우, 릴레이나 DC차단기 등을 사용하여 전력변환장치와 연동하는 것이 일반적이나, 이 경우 태양광모듈의 수명과 접속장치의 전압 강하 및 응답성 등의 문제를 야기한다. 또한, 전력변환장치 출력단의 커패시터에 초기 동작 시 과도한 동일전류가 발생하게 되고 이는 태양광모듈의 과전류 현상을 발생시켜 모듈의 수명과 더불어 퓨즈의 차단 및 발열 등 비이상적인 현상을 발생시킨다. 따라서, 본 논문에서는 이러한 문제점을 해결하고자 스위칭 소자를 사용한 접속장치 적용하였고, 소프트 스타팅 기법을 이용하여 돌입전류를 저감하고자 한다. 제안한 알고리즘의 경우, 시뮬레이션을 통해서 검증하고자 한다.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.4
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• pp.397-402
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• 2005

A new control algorithm of soft starter is proposed for the reduction of the inrush current during the grid connection of the induction-type wind power generator. Currently, the fixed speed wind turbine using induction generator is the most popular wind generation system in Korea. It is shown that the amount of inrush current mainly depends on the control algorithm of the soft starter, a thyristor-based grid connection device. For the simulation study, a 600kw wind turbine simulation model is developed and the transient waveforms are investigated with conventional md proposed methods. Also experimental results using 3.7kW experimental set-up show that the peak value of inrush current is reduced about 20$\%$ using proposed algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.484-488
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• 2000

This paper proposes a highy efficient inverter circuit for fluorescent lamp inverters using two state capacitors. A waveform of full-wave rectification used as a direct current power supply at fluorescent lamp inverters contains a lot of harmonic wave from inrush current which is generated near the maximum of input voltage with purse shape when voltage smoothing capacitor is charged. Therefore, In order to suppress inrush current which will result in harmonic wave, This paper proposed a method to control abrupt charging current by use of charging voltage at pre-state capacitor. As the result of it, power factor comes to be improved through the suppression of harmonic wave generation at supply current. Validity as to this experiment is confirmed through simulation.

• Journal of the Korean Magnetics Society
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• v.9 no.1
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• pp.64-70
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• 1999

The inrush current of transformer can flow when the overvoltage caused by surge or external faults is applied. In this paper, an algorithm for the calculation of this inruch current is proposed. The capacitances of windings are precalculated by using 3 dimensional FEM and are appended to circuit of the transformer. And transient characteristics of the transformer are analyzed by axisymmetric FEM which is coupled magnetic field of transformer and circuit of transformer. When a transformer encounters abnormal voltage, using the proposed method, internal magnetic field of transformer, voltages and currents of windings are calculated.