• 한국전기전자재료학회논문지
• /
• 제25권12호
• /
• pp.1021-1027
• /
• 2012

In this paper, multi-string power balancing system for streetlight was developed. Accordingly, the components of the system was developed, unit converters, MPPT control unit, a bank of Li-ion battery and controls the charging and discharging. Loss by improving the efficiency of the system through the parallel operation of the unit converter output will be reduced. And by improving the efficiency of the system through the unit converter parallel operation, output losses will be reduced. Charging and discharging efficiency of the device used in a typical solar streetlight is calculated based on the maximum power input. Because of the variation of the input power has a weakness. In this paper, flexible to changes in the input, and a system was developed to minimize the cost per watt. Measure the performance of the unit module from the system, the result was more than 91%. And the charging capacity 12 V/105 Ah, module power 180 W, respectively. Should expect to be able to improve performance through continuous monitoring in the future.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2015년도 춘계학술대회
• /
• pp.326-328
• /
• 2015

건물에서 창문의 기능은 태양 복사열의 유입을 통해 실내의 환경을 조성하고 동절기에는 난방비의 절감을 유도할 수 있으나, 다른 구조체에 비해 단열 성능이 크게 떨어져 5배 이상의 에너지가 손실되어 에너지 취약 부위이다. 또한 하절기에는 태양 복사열 과다로 냉방비가 가중된다. 이에 본 논문에서는 일반 가정에서 온도, 습도, 조도, 일사량 등의 실내 환경 정보를 이용하여 창문 자동 제어시스템을 개발하고자 한다. 이 시스템은 다양한 센서를 이용하여 실내 환경 정보를 수집하고 수집된 정보를 이용하여 모터를 제어하여 창문을 제어 할 수 있는 시스템이다. 가정 내 에너지 절감을 위하여 창호와 블라인드에 환경 자동화 서비스를 제공하여 사용자의 만족도를 높이고 스마트폰을 이용하여 시스템 제어를 통해 생활 속에 편리함을 제공하고자 한다.

• 한국태양에너지학회 논문집
• /
• 제34권2호
• /
• pp.1-7
• /
• 2014

Generally, buck converter controller is designed to control the output voltage of the converter. However, design of the controller in a photovoltaic power conditioning system is different from theoretical design guideline. The controller in a photovoltaic power conditioning system controls the input voltage of the converter (the output voltage of the solar cell) to meet a maximum power point tracking (MPPT) performance. In this study, a new model for buck converter used in a photovoltaic power conditioning system is proposed, which is linearized after state-space averaging in each period. Also, mathematical expression of the modeled buck converter is interpreted separately as small and large signals; therefore its appropriateness is measured to design linear voltage and current controller.

• 한국전자통신학회논문지
• /
• 제8권7호
• /
• pp.1039-1048
• /
• 2013

일반적으로 벅 컨버터 제어기는 컨버터의 출력 전압을 제어하도록 설계하지만, 태양광발전시스템에서의 벅 컨버터 제어기는 설계 방식을 달리 구분해야 한다. 본 논문에서는 MPPT(Maximum Power Point Tracking)을 위하여 벅 컨버터의 입력 전압(태양광전지의 출력 전압)을 제어한다고 가정하였다. 또한, 컨버터의 입력 전압을 제어하기 위한 새로운 벅 컨버터 모델을 제시한다. 이 컨버터 모델은 최대전력점(MPP)에서 동작점을 두어 선형화한 태양광전지의 모델을 포함하며, 모델의 타당성을 검증하기 위하여 대신호와 소신호로 나누어 분석한다. 또한 일반적인 선형제어기를 설계하였을 때, 제어 가능성을 분석하여 검증한다.

• 전력전자학회논문지
• /
• 제25권2호
• /
• pp.118-126
• /
• 2020

A solar array simulator is a special power supply that regulates the output voltage and current to simulate the characteristics of a photovoltaic panel. The operating point of the panel is difficult to control with a single controller because of the non-linearity of the output curve, which is determined by the amount of irradiation, temperature, and panel material. In the conventional method, the output curve is divided into sections through the current and the voltage mode controls. It reduces the overall performance of the system due to the interchanging control mode. By using the single mode controller, the noise interference of the measured value and the stability of the control around the maximum power point were demonstrated. To solve these issues, this study proposes a new unified controller. The stability of the controller was analyzed along with operating principles, and performance improvement was experimentally verified.

• 전기전자학회논문지
• /
• 제16권3호
• /
• pp.224-234
• /
• 2012

본 논문에서는 초소형 센서노드를 위한 MPPT(Maximum Power Point Tracking) 제어기능을 갖는 빛과 진동 에너지를 이용한 에너지 하베스팅 회로를 설계하였다. 설계된 회로는 MPPT 제어를 통해 온칩 솔라 셀과 압전소자로부터 최대 가용 전력을 수확하고, 수확된 에너지를 저장 커패시터에 병합하여 저장한다. 병합된 에너지는 PMU(Power Management Unit)를 통해 센서노드로 공급된다. MPPT 제어는 변환소자의 개방전압과 MPP 전압간의 비례관계를 이용하여 구현하였다. 제안된 회로는 0.18um CMOS 공정으로 설계하였으며, 모의실험을 통해 동작을 검증하였다. 설계된 에너지 하베스팅 회로와 온칩 솔라 셀의 칩 면적은 각각 $2.85mm^2$와 $8mm^2$이다.

• 한국주거학회논문집
• /
• 제23권1호
• /
• pp.27-41
• /
• 2012

The objective of this study is to develop the blind control strategy and method which reduce negative effect of incoming daylight on visual comfort of occupants, minimize psychological anxieties caused by frequent motions of a blind, and maximize positive effect of incoming daylight and solar irradiation by opening/closing of a blind. As previous researches on blind controls have limited outdoor environmental conditions to those in specific regions, orientations and dates, these resulted in problems at various conditions for general-purpose application. Major problem is that the time interval and amount of blind movement do not meet the control objective at the end of control zone and discontinuous curve. To overcome these limitations revealed in the previous researches, following tasks were performed in this study. 1) To establish the control objective to accomplish the goal of this study. 2) To develop the control methods and algorithms which prevent glare on the work-plane at any time and which control the time interval and amount of blind movement to follow the control objective at various profile angle curves. 3) To validate the general-purpose applicability and performance of the developed control methods and algorithms by simulation and its data analysis at various conditions. It was found that the proposed methods and algorithms can prevent the direct glare on the work-plane at all the time and also increase the incoming daylight and solar irradiation.

• 한국태양에너지학회 논문집
• /
• 제34권4호
• /
• pp.123-129
• /
• 2014

Photovoltaic and fuel cell systems can be used as power source in mobile robots. At this time the photovoltaic system generally generate power in daytime. The starting time of fuel cell is slower than the lithium battery. To compensate for these disadvantages, a battery charge-discharge system is used. Especially the bi-directional converter is used mainly in the charge-discharge method. The controller in a buck converter controls the input voltage of the converter to meet the maximum power point tracking(MPPT) performance. First of all, the simulations of hybrid system for battery charge-discharge system in each step simulated using solar and fuel cell modeling as input source in PSIM. Experiment of the buck and bi-directional converter system is conducted through using photovoltaic/fuel cel simulator(pCube) instead of solar and fuel cell. This hybrid system for battery charge discharge using photovoltaic/fuel cell generates emergency power for the communication system in mobile robot.

• Advances in aircraft and spacecraft science
• /
• 제5권4호
• /
• pp.459-475
• /
• 2018

In the field of aerospace engineering, accurate control of a spacecraft's orientation is often very important to mission success. Therefore, attitude control is a technically plentiful and extensively studied subject in controls literature during recent decades. This investigation of spacecraft attitude control is assumed to address two important aspects of the problem solutions. One sliding mode anti-disturbance control for utilization of faulty actuator components and another one disturbance observer based control to improve the pointing accuracy in the absence of anti-vibration equipment for the elastic appendages like a solar panel. Simultaneous occurrence of vibration due to flexible appendages and reaction degradation due to failure in attitude actuators complicates this case. The advantage of this method is acquisition proper control by the combination of disturbance observer and sliding mode compensation that form a fault tolerant control for the concerned satellite attitude control system. Furthermore, the proposed composite method indicates that occurrence the failure in actuators and even elastic solar panel vibration effect may be handled directly without reconfiguring the control components or providing piezoelectric devices. It's noteworthy, attitude quaternion and angular velocity commands are robustly tracked via controllers to become inclined to zero.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2009년도 제40회 하계학술대회
• /
• pp.1049_1050
• /
• 2009

This paper deals with development of a low cost VI(Voltage-Currrent)-tracer for PV(Photovoltaic) system using LabVIEW and DSP(Digital Signal Processor). Although the conventional VI-tracer is a high cost equipment, it can‘t abstract the detailed parameters of solar cell. To overcome above mentioned disadvantages, in this paper, a converter type VI-tracer is developed. The DSP, which controls the buck-boost DC-DC converter, is used to implement the proposed VI-tracer algorithm. The proposed VI-tracer can abstract more detailed parameters of solar cell; A(temperature constant), Rs(series resistance), and Rsh(parallel resistance). The authors emphasize that the proposed VI-tracer can satisfy the users who need to get various parameters. A comparison between the proposed VI-tracer and the conventional VI-tracer is presented to show the effectiveness of the proposed system.