• Journal of Power Electronics
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• 제2권3호
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• pp.155-161
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• 2002

This paper presents a maximum power point tracking algorithm for Photovoltaic array using only instantaneous output current information. The conventional Hill climbing method of peak power tracking has a disadvantage of oscillations about the maximum power point. To overcome this problem, we have developed an algorithm that will estimate the duty ratio corresponding to maximum power operation of solar cell. The estimation of the optimal duty ratio involves, finding the duty ratio at which integral value of output current is maximum. For the estimation, we have used the well know Lagrange's interpolation method. This method can track maximum power point quickly even for changing solar isolation and avoids oscillations after reaching the maximum power point.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.617-621
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• 2001

This paper presents a maximum power point tracking algorithm for Photovoltaic array using only instantaneous output current information. The conventional Hill climbing method of peak power tracking has a disadvantage of oscillations about the maximum power point. To overcome this problem, we have developed a algorithm, that will estimate the duty ratio corresponding to maximum power operation of solar cell. The estimation of the optimal duty ratio involves, finding the duty ratio at which integral value of output current is maximum. For the estimation, we have used the well know Lagrange's interpolation method. This method can track maximum power point quickly even for changing solar insolations and avoids oscillations after reaching the maximum power point.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권3호
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• pp.133-141
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• 2002

Most maximum power point tracking(MPPT) control algorithm is based on Perturb and Observe(P&O) and Incremental Conductance(IncCond). In comparison with P&O and IncCond algorithm, the dynamic and tracking characteristic of IncCond algorithm is better than P&O algorithm in condition of rapidly changing solar radiation. But in the case of digital implementation, the InCond algorithm has error en decision of maximum power operation point(MPOP). To solve this problem, this paper proposes a improved IncCond algorithm, which can determine the MPOP correctly by inserting the test signal in control input. This paper proposes a novel MPPT control algorithm for the digitally implemented photovoltaic system in condition of rapidly changing solar radiation. To verify the validity of the proposed control algorithm. the computer simulation and experiment are carried out.

• 한국정보통신학회논문지
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• 제17권5호
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• pp.1187-1195
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• 2013

태양광 인버터는 항상 태양전지 어레이의 최대 전력을 추종하며 동작해야 한다. 또한 태양광 인버터는 폭넓은 태양전지의 최대 전력점 전압과 관계없이 최대 전력점을 추종해야 한다. 태양전지의 전류리플이 발생한다면 최대 전력점 추종 기능이 저하되고 일사량 변동이나 최대 전력점 변동 시 정상적으로 추종하기 어려워진다. 이러한 문제점을 해결하기 위해 본 논문에서는 고효율의 새로운 최대 전력점 추종 알고리즘과 태양전지의 전류리플 감소 알고리즘을 제안하였다. 4KW급 계통연계형 태양광 인버터에 적용하여 실험한 결과 최대 전력점 추종 효율이 99.97%, 인버터 출력 효율은 97.5%, 인버터 전류의 고조파 총 왜곡률은 1.05%로 우수한 성능을 보였다. 또한 0.5초 동안 일사량을 100% -> 10%, 10% -> 100%로 급격히 변동하였을 때에도 안정된 최대 전력점 추종이 가능함을 알 수 있었다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.299-303
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• 2011

This paper proposes a novel sensorless maximum power point tracking (11PPT) algorithm for PV systems. The method is based on dividing the operating time into several intervals in which the PV terminals are short circuited in one interval and the calculated short-current of the PV is obtained and used to determine the optimum operating point where the maximum output power can be obtained. The proposed MPPT algorithm has been introduced into a current-controlled boost converter whose duty ratio is controlled to the maintain MPP condition. The same sequence is then repeated regularly capturing the PV maximum power. The main advantage of this method is eliminating the current sensor. Meanwhile, this MPPT algorithm reduces the power oscillations around the peak power point which occurs with perturbation and observation algorithms. In addition, the total cost will decrease by removing the current sensor from the PV side. Finally, simulation results confirm the accuracy of the proposed method.

• 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.

• 조명전기설비학회논문지
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• 제26권8호
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• pp.27-34
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• 2012

This paper proposes variable incremental conductance(IC) algorithm for maximum power point tracking(MPPT) control of photovoltaic. The conventional perturbation & observation(PO) and IC MPPT control algorithm generally uses fixed step size. A small step size reduces a tracking error in the steady state but slows a tracking speed in the transient state. Also, a large step size is fast a tracking speed but increases a tracking error. Therefore, this paper proposes variable IC MPPT algorithm that adjust automatically step size according to operating conditions. To improve a tracking speed and accuracy, when operating point is far from the maximum power point(MPP), the step size uses maximum value and when a operating point is near from the MPP, the step size uses variable step size that adjust according to slope of P-V curve. The validity of MPPT algorithm proposed in this paper prove through compare with conventional PO and IC MPPT algorithm.

• Journal of Power Electronics
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• 제18권4호
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• pp.1201-1210
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• 2018

The applications of thermoelectric generators (TEGs) have received a lot of attention both in terms of harvesting waste thermal energy and the need for multi-levels of power. It is critical to track the optimum electrical operating point using DC to DC converters controlled by a pulse that is generated through a maximum power point tracking algorithm (MPPT). In this paper, the hardware implementation of a short-current pulse algorithm has been demonstrated under steady stated and transient conditions. In addition, the MPPT algorithm has been proposed, which is one of the most effective and applicable algorithms for obtaining the maximum power point of TEGs. During this study, the proposed prototype has been validated both analytically and experimentally. It has also demonstrated successful performance, which highlights the claimed advantages of the proposed MPPT solution.

• 전기학회논문지
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• 제62권3호
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• pp.342-348
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• 2013

It proposes an efficient control algorithm to increase electric power transmission efficiency between photovoltaic power generating system and the grid. The main controller finds a maximum efficiency condition by considering the quantity of power generated from PV arrays, the number of inverters, and efficiency of PV inverter. According to the condition, a relay board arranges a point of contract of PV arrays. By the disposition of PV arrays, it assigns the optimized power on each PV inverter. Operational principle of the proposed maximum efficiency point tracking algorithm is given in detail. To verify the validity of the proposed approach, computer-aided simulation and experiment carried out.

• 전력전자학회논문지
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• 제24권2호
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• pp.111-119
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• 2019

In this study, constant power generation (CPG) algorithms are introduced for whole range power point tracking in photovoltaic systems. Currently, maximum power point tracking (MPPT) algorithm is widely used for high-power photovoltaic systems. However, MPPT algorithm cannot flexibly control such systems according to changing grid conditions. Maintaining grid stability has become important as the capacity of grid-connected photovoltaic systems is increased. CPG algorithms are required to generate the desired power depending on grid conditions. A grid-connected photovoltaic system is configured, and CPG algorithms are implemented. The performances of the implemented algorithms are compared and analyzed by experimental results.