• 전기학회논문지
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• 제65권4호
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• pp.593-600
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• 2016

The solar array regulator for low earth orbit satellites controls a operating point of solar array for suppling electric power to the battery and the other units. Because the control object is reversed, the new approach for large and small signal analysis is needed despite using buck-converter for power stage. In this paper, the steady state analysis of solar array regulator is performed in continuous conduction mode and discontinuous conduction mode, and the border condition for each mode is established. Also, the small signal model of solar array regulator is established in discontinuous conduction mode. Experiments are carried on in worst condition which the solar array regulator can face with discontinuous conduction mode. The results show that the solar array regulator is in stable.

• 동력기계공학회지
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• 제13권1호
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• pp.13-18
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• 2009

In this study, flow characteristics at the regulators, which is very important for clean gas supply systems for semiconductors and LCD industries, are investigated. Numerical simulations are carried out to visualize flows at regulators for several flow rates and to investigate pressure losses at some parts in the regulator. Velocity field at the regulator along with the detailed velocity field near the spring and near the valve is shown. New regulator models are proposed in this paper, and numerical simulations are also carried out to visualize flows at regulator for several flow rates, and to investigate pressure losses at the parts in new models. Pressure drops a lot across the valve seat. Pressure drop increases as mass flow rate increases. Especially for small opening, pressure drop increases rapidly as mass flow rate becomes large.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.574-576
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• 2008

Now there are two types Non-contact compensation AC automatic voltage regulator (A.V.R). One is transformer compensation regulator, whose principle is the combination of multiple compensation transformers, do the compensation by turning on and off the connections of the transformer through the multi-full bridge circuit. This method removed the mechanical drive and contacts, which increases the life and the dynamic performance of the A.V.R. However, the compensation is multilevel, and it needs many compensation transformers and switches, the circuit is complex, the compensation precision is low. Another type is PWM switch AC regulator, whose principle is getting the AC voltage from the input, then induce the AC compensation voltage through commutating and high frequency PWM transforming, and phase tracking. Here the compensation is step-less, the compensation precision is high, and the response is fast. But the circuit is complex, and it needs an inverse compensation transformer, which is difficult to realize high-power applications. In this paper, it shows an Automatic Voltage Regulator which use high frequency PWM inverter do compensation. This A.V.R has the function as the custom-power, which make the performance of the power supply in a high level.

• 전력전자학회논문지
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• 제8권5호
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• pp.463-467
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• 2003

본 논문에서는 교류쵸퍼와 직렬보상변압기로 구성되는 교류전압제어장치에 대하여 연구한다. 먼저, 교류쵸퍼와 직렬보상변압기로 구성되는 기본적인 교류전압제어장치로 출력전압을 입력전압에서 10-20%정도 강압할 수 있는 형태의 강압형 교류전압 제어장치를 제안하고 기본동작원리 및 이의 안전한 운전을 위한 PWM 발생과 초기시퀀스로직을 제시하였다. 또한 이로부터 입력전압변동에 무관하게 일정 출력전압을 발생시키기 위한 자동전압제어장치(AVR: Automatic Voltage Regulator)로 사용가능한 두가지 형태의 직렬보상형 교류전압제어장치를 제안하고 동작원리를 기술하였다. 특히, 입력전압과 반대방향의 극성의 전압을 발생시킬 수 있는 새로운 형태의 양방향 교류쵸퍼를 제안하고, 이의 안전한 운전을 위한 PWM 발생을 위한 스위칭 패턴을 제시하였다. 제안된 교류전압제어회로의 경우 다양한 실험을 통하여 전력절감을 목적으로 하는 강압형 교류전압제어장치와 자동전압조절기의 용도로 효과적으로 적용될 수 있음을 확인하였다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2014년도 추계학술대회
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• pp.639-642
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• 2014

상시전원이 공급되지 않은 광파표지에는 태양광을 이용한 전력공급시스템을 적용하고 있다. 이러한 전력공급시스템에서는 충전과 방전을 관리하는 충 방전조절기의 역할이 매우 중요하다. 최근 항로표지의 효과적인 관리를 위한 IT기술도입은 광파표지에 전력을 사용하는 장치를 추가하게 됨으로서 충 방전조절기의 중요성이 증가하고 있다. 현재 항로표지의 내부에 설치되어 운영되는 충 방전조절기의 점검은 접근성이 확보되지 않을 경우 점검하지 못하는 어려움이 있다. 이러한 문제를 해결하기 위해 본 논문에서는 충 방전조절기에 블루투스 모듈을 설치하여 접근성을 확보하였다. 또한 스마트폰의 블루투스 통신 기능을 이용하여 무선 점검이 가능한 모니터링시스템을 구현하였다. 구현한 시스템은 도입비용이 낮고 구성이 간편한 장점이 있다. 또한 충 방전조절기의 실시간 상태정보를 확인할 수 있어서 점검비용과 점검 간 발생 가능한 위험요소를 예방하는 효과가 있다.

• 전기학회논문지
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• 제58권5호
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• pp.918-922
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• 2009

The power expansion planning is large and capital intensive capacity planning. In the past, the expansion planning was established with the proper supply reliability in order to minimize social cost. However, the planning cannot use cost minimizing objective function in the power markets with many market participants. This paper proposed the power expansion planning process in the power markets. This system is composed of Regulator and GENCO's model. Regulator model used multi-criteria decision making rule. GENCO model is very complex problem. Thus, this system transacted the part by several scenario assuming GENCO model.

• Journal of Power Electronics
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• 제12권6호
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• pp.912-924
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• 2012

In hybrid renewable power systems, the use of a multiple-input dc/dc converter (MIC) leads to simpler circuit and lower cost, when compared to the conventional use of several single-input converters. This paper proposed a novel three-input buck/boost/buck-boost converter, which can be used in applications with various values of input voltage. The energy sources in this converter can deliver power to the load either simultaneously or individually in one switching period. The steady relationship, the power management strategy and the small-signal circuit model of this converter have been derived. With decoupling technology, modeling and regulator design can be obtained under multi-loop control modes. Finally, three generating methods of a multiple-input buck/boost/buck-boost converter is given, and this method can be extended to the other multiple-input dc/dc converters.

• Journal of Electrical Engineering and Technology
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• 제12권4호
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• pp.1593-1599
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• 2017

This paper presents a multi-channel light-emitting diode (LED) driver IC with a current-mode current regulator. The proposed current regulator replaces resistors for current sensing with a sequentially controlled single current sensor and a single regulation loop for sensing and regulating all LED channel currents. This minimizes the current mismatch among the LED channels and increases voltage headroom or, equivalently, power efficiency. The proposed LED driver IC was fabricated in a $0.35-{\mu}m$ BCD 60-V high voltage process, and the chip area is $1.06mm^2$. The measured maximum power efficiency is 93.4 % from a 12-V input, and the inter-channel current error is smaller than as low as ${\pm}1.3%$ in overall operating region.

• Journal of Power Electronics
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• 제19권1호
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• pp.34-43
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• 2019

An improved half-bridge LLC converter with a magamp auxiliary post-regulator is proposed in this paper. The function of the magamp is bypassed when the converter works within the low input-voltage range. Meanwhile, it operates as an auxiliary post-regulator when the input voltage is high. By changing the blocking time of the magamp, the dc gain of the converter can be extended. Hence, the input voltage range of the converter is extended. The realization of proposed topology does not require a complicated circuit. The controller of the magamp can be easily implemented using only passive components, transistors and an OP amp. The generalized operational principle is analyzed and the design criterion for the magamp is presented. Finally, a 25V output, 400W experimental prototype was built and tested for a 160-300V input-voltage range to verify the feasibility of the proposed method.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.589-592
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• 2002

The CCM (Continuous Conduction Mode) boost topology is generally used in the PFC (Power Factor Correction) regulator of household air-conditioning systems. There are three kinds of power devices-bridge rectifier diodes, FRDs (Fast Recovery Diodes), and IGBTs (or MOSFETs) - used In a boost PFC regulator. Selecting the appropriate device is very cumbersome work, specially, in the case of FRDs and IGBTs, because there are several considerations as described below: 1) High frequency leakage current regulation (conducted and radiated EMI regulation) 2) Power losses and thermal design 3) Device cost. It should be noted that there are trade-offs between the power loss characteristic of 2) and the other characteristics of 1) and 3). This paper presents a detailed evaluation by using several types of power devices, which can be unintentionally used, to show that optimal selection can be achieved. Based on the given thermal resistances, thermal analysis and design procedures are also described from a practical viewpoint.