• 제목/요약/키워드: Local MPPT

검색결과 17건 처리시간 0.024초

계통연계형 소형풍력발전 시스템의 직렬운전을 고려한 개선된 MPPT 방법 (Advanced Maximum Power Point Tracking Method for the Series Operation Strategy of Grid-Connected Small Wind Turbines)

  • 김용휴;허홍준;김장목
    • 전력전자학회논문지
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    • 제21권6호
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    • pp.497-505
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    • 2016
  • Operating wind turbine generators at maximum power point requires maximum power point tracking (MPPT) control methods. However, conventional methods cannot track the appropriate maximum power point in situations involving wind turbine systems based on a series operation strategy. These systems comprise one or more local maximum power points, and conventional methods can detect only one local maximum power point closed by a current operation point. This study proposes an advanced MPPT method for the series operation strategy of a small, grid-connected wind turbine system. In determining the appropriate maximum point, operations at certain local maximum power points are analyzed. The results show one appropriate point, which is tracked by the proposed MPPT method. The effectiveness of the proposed method is verified by the experimental results.

MPPT Control and Architecture for PV Solar Panel with Sub-Module Integrated Converters

  • Abu Qahouq, Jaber A.;Jiang, Yuncong;Orabi, Mohamed
    • Journal of Power Electronics
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    • 제14권6호
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    • pp.1281-1292
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    • 2014
  • Photovoltaic (PV) solar systems with series-connected module integrated converters (MICs) are receiving increased attention because of their ability to create high output voltage while performing local maximum power point tracking (MPPT) control for individual solar panels, which is a solution for partial shading effects in PV systems at panel level. To eliminate the partial shading effects in PV system more effectively, sub-MICs are utilized at the cell level or grouped cell level within a PV solar panel. This study presents the results of a series-output-connection MPPT (SOC-MPPT) controller for sub-MIC architecture using a single sensor at the output and a single digital MPPT controller (sub-MIC SOC-MPPT controller and architecture). The sub-MIC SOC-MPPT controller and architecture are investigated based on boost type sub-MICs. Experimental results under steady-state and transient conditions are presented to verify the performance of the controller and the effectiveness of the architecture.

Maximum Power Point Tracking under Partial Shading condition

  • Kashif, Muhammad Fayyaz;Park, Yongsoon;Sul, Seung-Ki
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2011년도 추계학술대회
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    • pp.40-41
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    • 2011
  • Partial shading on a Photo Voltaic panel can generate the local maximum power points on the powervoltage curve of the panel. Presence of the local peaks can disturb the efficient operation of maximum power point tracking (MPPT).In this study, the MPPT under partial shading condition is investigated. To circumvent the trappings into the local peaks, the results of the study are enumerated and discussed.

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부분 음영에서의 태양광 발전 효율을 높이기 위한 MPPT 전략 (MPPT Strategy to Improve Photovoltaic Power Generation Efficiency in Partial Shadows)

  • 허철영;김용래;이영권;이동윤;최익;최주엽
    • 한국태양에너지학회 논문집
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    • 제39권2호
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    • pp.1-9
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    • 2019
  • In order to increase the power generation efficiency of the photovoltaic system, a new algorithm that can follow the maximum power point of the photovoltaic power generation system having nonlinear output characteristics is proposed. Conventional maximum power point tracking (MPPT) algorithms such as Perturbation and Observation (P&O) and InCond (Increment and Conductance) schemes can not find the global maximum power point at a plurality of pole points in the unmatched state of unbalanced PV modules. However, even if the global maximum power point is found at a plurality of pole points, the global maximum power that can not be the real maximum power by the photovoltaic generation system. In order to solve this problem, a few PV companies propose installing several small PV inverters instead of if big one. However, since this will require additional costs, we herein propose a Multi-MPPT system using individual 3-point MPPT to track true MPPT at a plurality of pole points in the unmatched state of unbalanced PV modules.

태양광 발전시스템의 새로운 하이브리드 MPPT 제어 (A Novel Hybrid MPPT Control for Photovoltaic System)

  • 김수빈;조영민;최주엽;송승호;최익;이영권
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2014년도 추계학술대회 논문집
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    • pp.7-8
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    • 2014
  • 본 논문에서는 보편적으로 태양광 시스템에 적용되는 MPPT(Maximum Power Point Tracking) 기술들이 가지는 단점을 상호 보완하는 하이브리드 MPPT 제어 알고리즘을 제안하였다. 널리 사용되고 있는 MPPT 기술들을 비교하여 분석하였고, 이를 바탕으로 각 기술들의 단점을 상호 보완할 수 있는 요소들을 추출하여 MPPT 알고리즘에 적용하였다. 구현된 알고리즘은 최대전력점으로부터 동작점이 떨어져 있는 경우 빠르게 추적할 수 있는 속응성을 가지며, 정상상태에서는 안정도를 높이고, 국부적인 최대전력점(LMPP; Local Maximum Power Point) 발생 시 이를 감지하여 전체 특성 곡선의 최대전력점(GMPP; Global Maximum Power Point)을 찾아가도록 하였다. 또한 시뮬레이션을 통해 그 특성을 확인하였다.

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Moth-Flame Optimization-Based Maximum Power Point Tracking for Photovoltaic Systems Under Partial Shading Conditions

  • Shi, Ji-Ying;Zhang, Deng-Yu;Xue, Fei;Li, Ya-Jing;Qiao, Wen;Yang, Wen-Jing;Xu, Yi-Ming;Yang, Ting
    • Journal of Power Electronics
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    • 제19권5호
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    • pp.1248-1258
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    • 2019
  • This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

Improved Global Maximum Power Point Tracking for Photovoltaic System via Cuckoo Search under Partial Shaded Conditions

  • Shi, Ji-Ying;Xue, Fei;Qin, Zi-Jian;Zhang, Wen;Ling, Le-Tao;Yang, Ting
    • Journal of Power Electronics
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    • 제16권1호
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    • pp.287-296
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    • 2016
  • Conventional maximum power point tracking (MPPT) methods are ineffective under partially shaded conditions because multiple local maximum can be exhibited on power-voltage characteristic curve. This study proposes an improved cuckoo search (ICS) MPPT method after investigating the cuckoo search (CS) algorithm applied in solving multiple MPPT. The algorithm eliminates the random step in the original CS algorithm, and the conception of low-power, high-power, normal and marked zones are introduced. The adaptive step adjustment is also realized according to the different stages of the nest position. This algorithm adopts the large step in low-power and marked zones to reduce search time, and a small step in high-power zone is used to improve search accuracy. Finally, simulation and experiment results indicate that the promoted ICS algorithm can immediately and accurately track the global maximum under partially shaded conditions, and the array output efficiency can be improved.

Smoothing Output Power Variations of Isolated Utility Connected Multiple PV Systems by Coordinated Control

  • Datta, Manoj;Senjyu, Tomonobu;Yona, Atsushi;Sekine, Hideomi;Funabashi, Toshihisa
    • Journal of Power Electronics
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    • 제9권2호
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    • pp.320-333
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    • 2009
  • A Photovoltaic (PV) system's power output varies with the change of climate. Frequency deviations, tie line voltage swings are caused by the varying PV power when large PV power from several PV systems is fed in the utility. In this paper, to overcome these problems, a simple coordinated control method for smoothing the variations of combined PV power from multiple PV systems is proposed. Here, output power command is formed in two steps: central and local. Fuzzy control is used to produce the central smoothing output power command considering insolation, variance of insolation and absolute average of frequency deviation. In local step, a simple coordination is kept between the central power command and the local power commands by producing a common tuning factor. Power converters are used to achieve the same output power as local command power employing PI control law for each of the PV generation systems. The proposed method is compared with the method where conventional Maximum Power Point Tracking (MPPT) control is used for each of the PV systems. Simulation results show that the proposed method is effective for smoothing the output power variations and feasible to reduce the frequency deviations of the power utility.

무변압기형 3상 계통연계 PV PCS (Transformerless Three-Phase Line-connected Photovoltaic PCS)

  • 서현우;권정민;권봉환
    • 전력전자학회논문지
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    • 제12권5호
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    • pp.355-363
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    • 2007
  • 본 논문에서는 무변압기형 3상 계통연계 PV PCS (photovoltaic power conditioning system)를 제안하였다. 태양전지의 국소 최대 전력점에서 발전하는 것을 방지하여 최대 전력점에서 발전을 하도록 개선한 P&O (perturb and observe) 방식의 MPPT (maximum power point tracking) 알고리즘을 제안하였다. 3상 전압형 인버터를 외부 직류 링크 전압제어기, 내부 전류제어기, 그리고 마이크로컨트롤러로 구현하기에 적합하도록 간단화한 공간벡터 변조법을 통해 제어하여 3상 계통연계 시 단위 역률을 실현하였다. 그리고 시스템의 안정성 향상과 역률 개선을 위해 직류 링크 전압을 더 빠르고 정확하게 제어하기 위한 알고리즘을 제안하였다. 모든 알고리즘과 제어기를 하나의 마이크로컨트롤러로 구현하고 제안된 알고리즘과 제어기의 우수성을 실험을 통해 검증하였다.

Enhanced Simulated Annealing-based Global MPPT for Different PV Systems in Mismatched Conditions

  • Wang, Feng;Zhu, Tianhua;Zhuo, Fang;Yi, Hao;Fan, Yusen
    • Journal of Power Electronics
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    • 제17권5호
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    • pp.1327-1337
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    • 2017
  • Photovoltaic (PV) systems are influenced by disproportionate impacts on energy production caused by frequent mismatch cases. The occurrence of multiple maximum power points (MPPs) adds complexity to the tracking process in various PV systems. However, current maximum-power point tracking (MPPT) techniques exhibit limited performance. This paper introduces an enhanced simulated annealing (ESA)-based GMPPT technique against multiple MPP issues in P-V curve with different PV system structures. The proposed technique not only distinguishes global and local MPPs but also performs rapid convergence speed and high tracking accuracy of irradiance changing and restart capability detection. Moreover, the proposed global maximum power tracking algorithm can be applied in the central converter of DMPPT and hybrid PV system to meet various application scenarios. Its effectiveness is verified by simulation and test results.