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

• Journal of Power Electronics
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• 제14권4호
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• pp.722-732
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• 2014

The power-voltage (P-V) curve of photovoltaic (PV) arrays connected in parallel to bypass diodes would have several local maximum power points (LMPP) under partial shading conditions (PSC). Conventional maximum power point tracking (MPPT) methods fail to search for the global maximum power point (MPP) because the searched peak point may remain at the LMPP on the P-V curve under PSC. This study proposes an improved MPPT algorithm to ensure that PV arrays operate at global maximum power point (GMPP) under PSC. The proposed algorithm is based on a critical study and a series of observations of PV characteristics under PSC. Results show the regularity of voltage interval between LMPPs. The algorithm has the advantages of rapidly reaching GMPP, maintaining stability, and recovering GMPP quickly when the operating condition changes. Simulation and experimental results demonstrate the feasibility of the proposed algorithm.

• 전력전자학회논문지
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• 제22권3호
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• pp.199-206
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• 2017

Maximum Power Point Tracking (MPPT) control needs to generate the maximum power of a tidal current turbine. A tidal current speed sensor is required to achieve effective generated power in a tidal current generation system. The most common methods used to achieve such power is the tip speed ratio of turbine and tidal current information. However, these methods have disadvantages, such as expensive installation of the tidal current sensor, parameter errors in turbine design, and different information according to the installed position of the tidal current sensor. This paper proposes a maximum power control scheme using perturb-and-observe (P&O) for tidal current generation system. The proposed P&O MPPT scheme can achieve the maximum power without tidal current sensors and turbine design parameters. The reliability and suitability of the proposed control scheme are proven through simulation and experiment results at the tidal current generation laboratory.

• Journal of Power Electronics
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• 제18권6호
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• pp.1805-1818
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• 2018

This paper proposes a novel hybrid maximum power point tracking (MPPT) algorithm combining a Whale Optimization Algorithm (WOA) and the conventional Perturb & Observation (P&O) to track/extract the highest amount of power from a solar photovoltaic (SPV) system working under partial shading conditions (PSCs). The proposed hybrid algorithm is based on a WOA which predicts the initial global peak (GP) and is followed by P&O in the final stage to achieve a quicker convergence to a GP. Thus, this hybrid algorithm overcomes the computational burden encountered in a standalone WOA, grey wolf optimization (GWO) and hybrid GWO reported in the literature. The conventional algorithm searches for the maximum power point (MPP) in the predicted region by the WOA. The proposed MPPT technique is modelled and simulated using MATLAB/Simulink for simulating an environment to check its effectiveness in accurately tracking the MPP during the GP region. This hybrid algorithm is compared with a standalone WOA, GWO and hybrid GWO. From the simulating results, it is shown that the proposed algorithm offers high tracking performance and that it increases the output power level of a SPV system under partial shading. The algorithm also verified experimentally on various PSCs.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.85-95
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• 2008

Photovoltaic conditioning systems normally use a maximum power point tracking (MPPT) technique to deliver the highest possible power to the load continuously when variations occur in the insolation and temperature. A unique method of tracking the maximum power points (MPPs) and forcing the boost converter system to operate close to these points is presented through deriving small-signal model and transfer function of boost converter considering input capacitor. This paper aims at modeling boost converter including fairly large equivalent series resistance(ESR) of input reservoir capacitor by state-space-averaging method and PWM switch model. In the future, properly designed controller for compensation will be constructed in 3kw real system for maximum photovoltaic power tracking control.

• Journal of Power Electronics
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• 제19권5호
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• pp.1259-1269
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• 2019

PV system performance is dependent on different irradiations and temperature values in addition to the capability of the employed PV inverter / maximum power point tracker (MPPT) circuit or algorithm. Therefore, it would be appropriate to use a PV simulator capable of producing identical repeatable conditions regardless of the weather to evaluate the performance of inverter / MPPT circuits and algorithms. In accordance with this purpose, a photovoltaic (PV) array simulator is presented in this paper. The simulator is designed to generate current-voltage (I-V) and power-voltage (P-V) curves of a PV panel. Series connected cascaded modules constitute the basic part of the simulator. This feature also allows for the modeling of PV arrays since the number of modules can be increased and high voltage values can be reached with the simulator. In addition, the curves obtained at the simulator output become similar to the actual curves of sample PV panels with an increase in the number of modules. In order to show the validity of the proposed simulator, it was simulated for various situations such as panels under full irradiance and partial shading conditions. After completing simulations, experiments were realized to support the simulation study. Both simulation and experimental results show that the proposed simulator will be very useful for researchers to carry out PV studies under laboratory conditions.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.207-209
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• 2019

This paper proposes a grid-tied photovoltaic (PV) system, consisting of Voltage-fed dual-active-bridge (DAB) dc-dc converter with single phase inverter. The proposed converter allows a small dc-link capacitor, so that system reliability can be improved by replacing electrolytic capacitors with film capacitors. The double line frequency free maximum power point tracking (MPPT) is also realized in the proposed converter by using Ripple Correlation method. First of all, to eliminate the double line frequency ripple which influence the reduction of DC source capacitance, control is developed. Then, a designing of Current control in DQ frame is analyzed and to fulfill the international harmonics standards such as IEEE 519 and P1547, $3^{rd}$ harmonic in the grid is directly compensated by the feedforward terms generated by the PR controller with the grid current in stationary frame to achieve desire Total Harmonic Distortion (THD). 5-kW PV converter and inverter module with a small dc-link film capacitor was built in the laboratory with the proposed control and MPPT algorithm. Experimental results are given to validate the converter performance.

• 한국항해항만학회지
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• 제42권3호
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• pp.167-176
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• 2018

해상에서 운용되는 일점계류형 해양플랜트의 태양광 발전 시스템은 독립 전원 체계를 가지고 있으며, 해상 환경, 부조일수 등의 영향으로 안정적인 전력을 공급하는 것이 중요하다. 이러한 이유로 태양광 패널을 여러 방향으로 설치하게 되는데, 이 때 각 패널마다 입사되는 광량이 달라지므로 부분음영현상이 발생하게 된다. 육상용 태양광 발전시스템의 발전량은 위도의 영향을 받으므로 우리나라의 경우 $30{\sim}36^{\circ}$ 사이의 각도로 설치하는 것이 일반적이나, 일점계류형 해양플랜트에 설치되는 태양광 발전 시스템의 경우 부분 음영 현상에 의해 최대전력점이 제어 가능 범위 밖에 존재하는 경우가 발생하게 되고 이는 전력 발전 손실이 된다. 이 때 두 패널의 광량차이를 줄임으로써, 최대 전력점을 MPPT 알고리즘이 추종 가능한 범위에 존재하게 하여 발전 효율을 더 높일 수 있으며, 시뮬레이션 결과 설치각도 $20^{\circ}$에서 가장 높은 발전 효율 가짐을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1390-1391
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• 2011

태양광 발전 시스템에서의 최대 전력점 추적(MPPT, Maximum Power Point Tracking)제어를 실험을 하기 위해 부분선형 다이오드 모델을 이용한 태블로 해석을 통해 태양광 발전 시스템의 태양전지 모듈의 특성을 시뮬레이션 하였다. 태양전지 모듈의 V-I 특성과 태양전지 패널을 직렬-병렬 어레이로 연결 시, 부분 그늘 문제(Partial Shading Problem)의 지역 최대 점(global peak)을 시뮬레이션을 통해 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.182-184
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• 2007

이 논문에서는 계통연계형 3KW 태양광 발전 시스템 개발에 필요한 기본적인 요소기술로서 MPPT(Maximum Power Point Tracking), 계통연계를 위한 단상 PLL(Phase Locked Loop), 피크전압검출법과 전류제어기법 등을 살펴보고 이를 시뮬레이션으로 검증하였다. 또한 검증된 기법등을 토대로 3kW 태양광 발전 PCS(Power Conditioning System)에 적용실험을 통해 결과를 확인하였다.