基于改进蜜獾优化算法的光伏MPPT研究

光伏阵列的输出功率易受外界影响而呈现功率多峰值现象,传统的最大功率追踪算法难以寻得最优功率输出。为了提升光伏发电系统的效率,提出一种改进的蜜獾优化算法作为光伏最大功率点追踪的方法。结合Tent映射,使种群在初始化过程中均匀分布,以增加算法全局寻优能力。在Matlab2018b/Simulink环境下仿真,基于Boost电路验证最大功率的追踪效果,结果显示,该方法在不同工况下,较粒子群算法的MPPT,均具有较好的追踪效果,且改进的HBA算法较HBA本身,追踪时间缩短了0.104 s。     

局部遮挡条件下的光伏阵列最大功率点跟踪

针对局部遮挡条件下光伏阵列存在多个局部峰值的问题,以准确跟踪到光伏阵列的全局最大功率点为目标,提出一种新型的局部遮挡条件下光伏阵列最大功率点跟踪方法。首先深入分析了局部遮挡条件下的光伏阵列输出特性,并构建了相应的数学模型,然后采用改进扰动观察法搜索到全局最优的光伏阵列最大功率点,防止陷入局部最优点难题,最后采用Matlab 2014仿真软件对其性能进行分析。结果表明,本文方法可以快速、准确找到光伏阵列最大功率点,提高了光伏阵列的输出效率。     

基于Fibonacci搜索的光伏发电MPPT控制策略

介绍一种采用Fibonacci数列搜索指导光伏发电最大功率点跟踪(MPPT)的方法,分析验证了Fibonacci搜索方法适用于时变P-V特性的光伏阵列.利用Fibonacci数列搜索算法可实现简化的MPPT实时控制,使其在非均匀或瞬变的日照条件下,能实现对最大功率点的快速准确跟踪.该方法可应用于多种光伏电站的电源变换控制,包括DC/DC及DC/AC变换器,优点是不需要测量温度和日照水平,也无需精确的光伏阵列模型.理论分析和仿真模拟验证表明,Fibonacci算法与目前被广泛应用的增量电导法相比,具有输出效率高,响应速度快,搜索范围大的特点,通常可以追踪到整个光伏阵列的真实最大功率,具有优良的控制性能.     

基于模糊控制的光伏并网逆变器MPPT控制研究

最大功率点跟踪控制的目的是为了将光伏阵列发出的最大能量实时地提供给负载,使光伏发电系统的能量利用率达到最大。在光伏阵列产生电能的应用中,有许多不确定因素,如太阳光照强度、光伏阵列温度的变化、负载的变化、光伏阵列输出特性的非线性,则建立模型分析光伏阵列输出最大功率要考虑很多的因素。从模糊控制技术的分析中知道,模糊控制不需要对被控对象建立精确的数学模型,是一种相对简单的智能控制方法,对处理非线性问题有很好的效果。因此,用模糊控制法来实现MPPT可以得到比较好的效果。本文基于此研究了光伏阵列的非线性功率输出特性,建立了基于Matlab simulink/Power system的光伏阵列仿真模型,对基于模糊控制采用扰动观察法进行光伏发电最大功率点跟踪进行了仿真验证。     

基于细菌觅食算法的光伏阵列MPPT控制方法

针对光照不均匀条件下光伏阵列P-V输出特征呈现多波峰,传统算法无法摆脱局部最优值的缺点,提出了一种基于细菌觅食的优化算法,并首次应用于光伏阵列的最大功率点跟踪(MPPT)。算法引入了趋向性操作,用以进行局部范围内的最优寻找。分析了光伏阵列在遮挡条件下输出功率的变化特性,然后使用细菌觅食算法进行了最大功率点跟踪控制方法实验。实验表明,该算法能够成功摆脱局部最优值的约束,快速寻找到全局最大功率点,控制精度高,为光伏阵列最大功率点跟踪提供了一种新的实现方法。     

光伏并网系统中的最大功率点追踪控制

太阳能电池阵列输出特性具有强烈的非线性,为了提高系统的整体效率,一个重要的途径就是实时调整光伏电池的工作点,进行最大功率点跟踪(MPPT),使之始终工作在最大功率点附近。对并网系统的DC-DC电路原理和控制方法进行了研究,利用增量电导算法,通过脉宽调制的办法实现最大功率点的追踪,并用实验证实了其可行性和正确性。     

三相光伏并网发电系统MPPT的研究

针对光伏发电系统中光伏阵列的输出功率易受外部环境影响而降低了系统效率的问题,文中采用了Buck-Boost电路和基于最优梯度法的最大功率点跟踪控制方法。该控制系统能使光伏发电系统输出功率快速跟踪外部环境的变化,同时能有效消除或减弱光伏阵列在最大功率点附近的功率振荡现象,从而提高了光伏阵列的利用率。利用Matlab/Simulink建立仿真模型,验证论文提出的方案并得出可行结果。     

部分遮挡下光伏组件MPPT技术研究

因云雾、植物、建筑等物体遮挡,或光伏器件本身的不一致性,可能导致多个功率极值出现,从而使传统的最大功率点跟踪方法失效。在光伏组件出现多功率极值的条件下,采用合理最大功率追踪算法,不陷入局部最大功率点,找到全局最大功率点值得研究。文中提出结合粒子群优化和常规最大功率点跟踪的复合算法,用于实现最大功率点跟踪,并与常规最大功率点跟踪算法进行仿真实验比较。以解决光伏组件工作在恶劣条件下的严重功率失配问题,提高光伏组件的能量转换率,保护光伏组件不受损坏。     

基于占空比模糊控制的光伏发电系统MPPT技术

为了有效地利用太阳能,有必要对光伏发电系统进行最大功率点跟踪(MPPT)控制研究。文中以两级式光伏并网发电系统为研究对象,建立了任意外界环境下的光伏阵列数学模型。由于光伏阵列的非线性输出特性,将模糊控制思想引入最大功率点跟踪,提出占空比模糊控制的扰动观察法的MPPT控制策略,并通过计算机进行仿真验证。与传统的占空比扰动观察法相比较,该方法能够更加快速、准确地跟踪上太阳能电池的最大功率点。     

基于改进扰动观察法的光伏阵列最大功率跟踪器的研究

光伏阵列由于输出特性具有非线性,为了提高发电效率,需要对其进行最大功率点跟踪（MPPT）。提出了一种基于改进扰动观察法的最大功率点跟踪器的设计方案,该方案在实现最大功率跟踪的基础上,解决了传统扰动观察法在响应速度与跟踪精度之间的矛盾。通过实验对比引入MPPT前后光伏阵列的输出,验证了方案的可行性与有效性。     

Integrated photovoltaic maximum power point tracking converter

A low-power low-cost highly efficient maximum power point tracker (MPPT) to be integrated into a photovoltaic (PV) panel is proposed. This can result in a 25% energy enhancement compared to a standard photovoltaic panel, while performing functions like battery voltage regulation and matching of the PV array with the load. Instead of using an externally connected MPPT, it is proposed to use an integrated MPPT converter as part of the PV panel. It is proposed that this integrated MPPT uses a simple controller in order to be cost effective. Furthermore, the power converter has to be very efficient, in order to transfer more energy to the load than a directly-coupled system. This is achieved by using a simple soft-switched topology. A much higher conversion efficiency at lower cost will then result, making the MPPT an affordable solution for small PV energy systems     

Combined low-cost, high-efficient inverter, peak power tracker andregulator for PV applications

A novel compound power converter that serves as a DC-to-AC inverter, maximum power point tracker (MPPT), and battery charger for stand-alone photovoltaic (PV) power systems is introduced. A theoretical analysis of the proposed converter is performed, and the results are compared with experimental results obtained from a 1.5 kW prototype. The overall cost of PV systems can thus be reduced by using load management control and efficiency-optimization techniques. Power flow through the converter is controlled by means of a combination of duty cycle and output frequency control. With load management, large domestic loads, such as single phase induction motors for water pumping, hold-over refrigerators, and freezers, can be driven by day at a much higher energy efficiency. This is due to the high efficiency of the inverter with high insolation, and because the inverter uses the energy directly from the solar array. The battery loss component is thus reduced     

Development of a microcontroller-based, photovoltaic maximum powerpoint tracking control system

Maximum power point tracking (MPPT) is used in photovoltaic (PV) systems to maximize the photovoltaic array output power, irrespective of the temperature and irradiation conditions and of the load electrical characteristics. A new MPPT system has been developed, consisting of a buck-type DC/DC converter, which is controlled by a microcontroller-based unit. The main difference between the method used in the proposed MPPT system and other techniques used in the past is that the PV array output power is used to directly control the DC/DC converter, thus reducing the complexity of the system. The resulting system has high-efficiency, lower-cost and can be easily modified to handle more energy sources (e.g., wind-generators). The experimental results show that the use of the proposed MPPT control increases the PV output power by as much as 15% compared to the case where the DC/DC converter duty cycle is set such that the PV array produces the maximum power at 1 kW/m² and 25°C     

A fuzzy-logic-controlled single-stage converter for PV-poweredlighting system applications

This paper presents a fuzzy-logic-controlled single-stage power converter (SSC) for photovoltaic (PV)-powered lighting system applications. The SSC is the integration of a bidirectional buck-boost charger/discharger and a class-D series resonant parallel loaded inverter. The designed fuzzy logic controller (FLC) can control both the charging and discharging current, and can improve its dynamic and steady-state performance. Furthermore, a maximum power point tracker (MPPT) based on a perturb-and-observe method is also realized to effectively draw power from PV arrays. Both the FLC and the MPPT are implemented on a single-chip microprocessor. Simulated and experimental results obtained from the proposed circuit with an FLC have verified the adaptivity, robustness and feasibility     

Residential photovoltaic energy storage system

This paper introduces a residential photovoltaic (PV) energy storage system, in which the PV power is controlled by a DC-DC power converter and transferred to a small battery energy storage system (BESS). For managing the power, a pattern of daily operation considering the load characteristic of the homeowner, the generation characteristic of the PV power, and the power-leveling demand of the electric utility is prescribed. The system looks up the pattern to select the operation mode, so that powers from the PV array, the batteries and the utility are utilized in a cost-effective manner. As for the control of the system, a novel control technique for the maximum power-point tracking (MPPT) of the PV array is proposed, in which the state-averaged model of the DC-DC power converter, including the dynamic model of the PV array, is derived. Accordingly, a high-performance discrete MPPT controller that tracks the maximum power point with zero-slope regulation and current-mode control is presented. With proposed arrangements on the control of the BESS and the current-to-power scaling factor setting, the DC-DC power converter is capable of combining with the BESS for performing the functions of power conditioning and active power filtering. An experimental 600 W system is implemented, and some simulation and experimental results are provided to demonstrate the effectiveness of the proposed system     

A PSO‐based maximum power point tracking for photovoltaic systems under environmental and partially shaded conditions

To increase the efficiency of photovoltaic (PV) systems, maximum power point (MPP) tracking of the solar arrays is needed. Solar arrays output power depends on the solar irradiance and temperature. Also the mismatch phenomenon caused by partial shade will affect the output power of solar systems and lead to the incorrect operation of conventional MPP tracker. Under partially shaded conditions, the solar array power–current characteristic has multiple maximum. This paper presents a maximum power point tracking (MPPT) with particle swarm optimization method for PV systems under partially shaded condition. The performance of the proposed method is compared with perturb and observe (P&O), improved P&O, voltage‐based maximum power point tracking and current‐based maximum power point tracking algorithms, especially, under partially shaded condition. Simulation results confirm that proposed MPPT algorithm with high accuracy can track the peak power point under different insolation, temperature and partially shaded conditions, and it has the best performance in comparison with four mentioned MPPT algorithms. Also under rapidly changing atmospheric conditions, the P&O algorithm is diverged. Copyright © 2013 John Wiley & Sons, Ltd.     

CMOS integrated MPP tracker with analog power measurement at the PV converter input

An integrated converter controller with maximum power point (MPP) regulation in 0.35 μm CMOS for photovoltaic (PV) applications is reported. The implemented MPP tracker bases on a perturb and observe algorithm and acquires the information concerning the power flow via an analog processing circuit which is connected at the switched mode converter input respectively the output of the attached PV string of nine cells. There the solar cell current is measured via a very low-ohmic shunt resistor of 1 mΩ and analogously multiplied with the cell voltage. As output the fabricated test chip directly generates a 530 kHz PWM signal for the external switched mode converter. Measurements show that under similar conditions analog MPP tracking of the converter input power improves the robustness with respect to settling times of the power path compared to those topologies at which the power is measured at the converter output. Between 0.4 and 7.5 A photocurrent the chip achieves tracking efficiencies better than 99.5 % while the power consumption is only 750 μW and a very low chip area demand of 0.043 mm² for the MPP tracking core is achieved.     

A low‐cost photovoltaic emulator for static and dynamic evaluation of photovoltaic power converters and facilities

In testing maximum power point tracking (MPPT) algorithms running on electronic power converters for photovoltaic (PV) applications, either a PV energy source (PV module or PV array) or a PV emulator is required. With a PV emulator, it is possible to control the testing conditions with accuracy so that it is the preferred option. The PV source is modeled as a current source; thus, the emulator has to work as a current source dependent on its output voltage. The proposed emulator is a buck converter with an average current mode control loop, which allows testing the static and dynamic performance of PV facilities up to 3 kW. To validate the concept, the emulator is used to evaluate the MPPT algorithm of a 230‐W experimental microinverter working from a single PV module. Copyright © 2012 John Wiley & Sons, Ltd.     

太阳电池最大功率点跟踪研究

根据太阳电池的特性,设计了一种基于“二次插值法”的太阳能电池最大功率跟踪器,并对设计的MPPT控制器进行了测试。实验结果表明它有较好的跟踪性能。