Photovoltaic Power Tracking Research Articles

Sampling Time Modulation of a Photovoltaic Power Tracking Controller Based Upon Real-Time Monitoring of Converter Dynamics

Sampling Time Modulation of a Photovoltaic Power Tracking Controller Based Upon Real-Time Monitoring of Converter Dynamics

Study on impact of photovoltaic power tracking modes on photovoltaic-photothermal performance of PV-PCM-Trombe wall system

Due to the lack of research on the impact of photovoltaic (PV) power tracking methods on the performance of Building-Integrated Photovoltaic-Thermal (BIPV/T) systems, this study comparatively analyzes the photovoltaic-photothermal performance of the PV-PCM-Trombe Wall system operating in Pulse Width Modulation (PWM) and Maximum Power Point Tracking (MPPT) modes during winter passive heating conditions. Additionally, the study investigates the influence of these modes on the thermal characteristics of buildings. The results indicate that the MPPT strategy achieved a PV efficiency of 15.50 %, while the PWM strategy resulted in a significant reduction to 12.72 % (a decrease of 2.78 % compared to MPPT). Importantly, both strategies effectively utilized solar energy for passive space heating without noticeable differences in photothermal performance. Furthermore, the study observed that the upper part of the PCM plate reached higher peak temperatures earlier in the vertical dimension. Experiment A exhibited peak temperatures ranging from 33.57 °C to 34.76 °C, while Experiment B had a wider range of 27.99 °C to 36.10 °C. Minimal temperature variations were observed across the PCM plate in the thickness direction, measuring only 0.60 °C in Experiment A and 0.70 °C in Experiment B. These research findings provide valuable insights into the roles and impacts of different PV power tracking strategies in PV-PCM-Trombe wall systems.

An experimental realization of improved grid integrated multilevel inverter based PV systems with MPPT

AbstractThis research work explains a sliding mode controller‐based multilevel inverter for grid integrated photovoltaic power structure. A gravitational search algorithm based on maximum power point tracking has also been discussed for optimal photovoltaic power achievement. Moreover, a two‐stage cascaded interleaved boost converter has been employed, which provides minimised voltage/current ripple, higher current/power density, better efficacy, faster response, and reduced electromagnetic interference as major benefits. The multilevel inverter's proposed constant frequency‐based sliding mode controller provides better transient responses, high photovoltaic power tracking, and good robust behaviour under changing operating conditions. The proposed sliding mode controller has a fixed frequency operation and has low reactivity to parameter divergence. The proposed multilevel diode clamped inverter for grid integrated photovoltaic system provides a reduced number of components and a power rating. The gravitational search algorithm‐based swarm technique as a maximum power point tracking provides high convergence velocity, better accuracy, and good local search capability. The experimentation was carried out to implement control algorithms using the dSPACE platform. The designed multilevel inverter system with proposed control provides average 89.2% inverter efficiency under variation of sun insolations.

A novel hybrid grey wolf optimized fuzzy logic control based photovoltaic water pumping system

AbstractThis paper describes the novel scientific contribution of a modified hybrid grey wolf optimization‐fuzzy logic controller (GWO‐FLC) based on maximum power point tracking (MPPT) for a photovoltaic (PV) system. The modified GWO eliminates the lower rank (δ) and lowest rank (Ψ) wolves, which provides a rapid search method to track global maximum point (GMPP) in a lesser period. The hybrid GWO‐FLC based MPPT technique provides tracking of GMPP with zero oscillations and high PV power tracking under rapid weather fluctuations. The GWO technique acquires GMPP and provides soft tuning of fuzzy parameters to achieve high PV power tracking with zero oscillations around GMPP. The experimental responses confirm changing environmental situations. The dSPACE real‐time platform has been employed to validate the proposed hybrid MPPT controller design, which provides optimal PV power tracking with accurate efficiency, fast convergence velocity, and less computational period. The switched reluctance motor (SRM) driven PV water pump is proposed in this research work. The proposed PV water pumping has low cost and no voltage, and current sensors are employed to generate a gating pattern of an SRM based mid‐point converter, which reduces the losses.

An adaptive TS‐fuzzy model based RBF neural network learning for grid integrated photovoltaic applications

In this research work, an adaptive TS-fuzzy based RBF neural network (ATSFRBFNN) algorithm based maximum power point tracker (MPPT) is employed for grid integrated photovoltaic (PV) system. The novel learning algorithm provides accurate and rapid PV power tracking under fluctuating solar insolation. However, an improved damping circulating current limiting inverter controller is employed to generate gating signal of voltage source inverter and to deliver reduced harmonic constant, less power loss, mitigation of power quality issues regulation of Dc-link voltage utilization for grid integrated PV system under steady, and transient weather conditions. The experimental results justify the improved system performance under varying operating conditions. The behaviour of novel hybrid PV MPPT structure is compared with TS-fuzzy, RBFNN, and GA-RBF for higher tracking efficacy, least tracking deviation, accurate responses, and zero steady-state power oscillation around MPP region.

Power reserve control strategy in the left‐side of maximum power point for primary frequency regulation of grid‐connected photovoltaic systems

The traditional method of operating photovoltaic (PV) systems on the right side of the maximum power point (MPP) may cause the voltage to be close to the open-circuit voltage of the PV panel, resulting in a large oscillation of the PV power. In contrast, the change in dP/dU value of the curve on the left of the MPP is small, which is more conducive to adjusting the output power of the PV. A frequency regulation control strategy is proposed for a single-stage PV power plant (PVPP), maintaining the PV string operating on the left side of the MPP. This paper proposes an optimal step-size calculation method based on the flexible power tracking evaluation function. This calculation method is suitable for PV operating on the left side of the MPP and can improve the dynamic and steady-state performance of the PV power tracking process. In addition, the system response is analyzed by establishing a small-signal model with PV operating on the left side of the MPP. Finally, simulations and experiments verify the correctness and accuracy of the proposed primary frequency regulation strategy and step-size calculation method.

A robust maximum power point tracking control for PV panel using adaptive PI controller based on fuzzy logic

Most methods of maximum power point tracking (MPPT) for photovoltaic (PV) focus only on tracking performance while robustness against disturbances hasrarely been addressed. This paper proposes a new MPPT control method that provides robustness against direct current (DC) link voltage disturbance as well as good tracking performance. The method uses indirect MPPT control topology which incorporates two controllers. For the external controller, we use an adaptive proportional-integral (PI) control which is real-time tuned by fuzzy logic (FL). New membership functions and rule base are proposed using only one fuzzy input variable and 10 fuzzy rules. The internal controller is a PI controller. The PV panelis connected to a boost DC-DC converter. The proposed MPPT control iscompared with the fuzzy logic controller (FLC). Performance is evaluated under DC link voltage disturbance, steady-state condition, and rapid solar radiation changes. Simulation results indicate that the proposed method provides 41.2 % better robustness against DC link voltage disturbance as compared to the direct FLC. Experimental results under natural climate conditions with real solar radiation validate that the proposed method works well in regulating the MPP at steady-state solar irradiance as well as in tracking the MPP towards rapid solar irradiance changes. It yields the PV power tracking speed of 95.75 W/s.

An Improved Particle Swarm Optimization Algorithm Suitable for Photovoltaic Power Tracking Under Partial Shading Conditions

The partial shading of a photovoltaic array repeatedly occurs in the natural environment, which can cause a failure of a conventional maximum power point tracking (MPPT) algorithm. In this paper, the convergence conditions of the standard particle swarm optimization (PSO) algorithm are deduced by the functional analysis, and then the influence of the random variables and inertia factor of the algorithm on the trajectory in the particle swarm optimization is analyzed. Based on the analysis results, an improved particle swarm optimization (IPSO) algorithm, which adopts both global and local modes to locate the maximum power point, is proposed. Compared to the standard PSO algorithm, in the improved PSO algorithm, many random and interfered variables are removed, and the structure is optimized significantly. The proposed algorithm is first simulated in MATLAB to ensure its capability. The feasibility of the approach is validated through physical implementation and experimentation. Results demonstrate that the proposed algorithm has the capability to track the global maximum power point within 3.3 s with an accuracy of 99%. Compared with five recently developed Global MPPT algorithms, the proposed IPSO algorithm achieved better performance in the maximum power tracking in the partial shading conditions.

A New Scheme Based on Climbing Method for Maximum Photovoltaic Power Tracking Control

The maximum power point tracking (MPPT) of photovoltaic arrays can increase the output power of the photovoltaic systerm, improve the utilization of solar energy. This paper describes the output characteristics of the photovoltaic arrays and the principle of maximum power point tracking,then,based on Incremental conductance method, proposes a sub-type of the variable step size MPPT algorithm. simulated using MATLAB/Simulink, the final results show that the proposed algorithm is able to quickly track the maximum power point and power concussion problem has been significantly improved.

Using Self-Synchronization Error Dynamics Formulation Based Controller for Maximum Photovoltaic Power Tracking in Micro-Grid Systems

This paper proposes a self-synchronization error dynamics formulation based controller for maximum photovoltaic power tracking (MPPT) of a photovoltaic (PV) array. The output power conversion of a PV array depends on atmospheric conditions, such as the solar radiation and ambient temperature, and its conversion efficiency is low. Therefore, a MPPT controller is necessary for a PV conversion system, in order to improve the output power. A PV cell is a p-n semiconductor junction. Photon motion, temperature, or electricity conduction cause anomalous diffusion phenomena in inhomogeneous media. In order to describe nonlinear-characteristics, fractional-order calculus can be used to express the dynamic behaviors using fractional-order incremental conductance and to adjust the terminal voltage to the maximum power point. Inspired by the synchronization of Sprott system, a voltage detector is formulated to trace the desired voltage and to control the duty cycle of a boost converter. For a small photovoltaic system, the numerical experiments demonstrate that the proposed method can reduce the tracking time and can improve the conversion efficiency.

A Fast PV Power Tracking Control Algorithm With Reduced Power Mode

This paper presents a fast maximum power point tracking (MPPT) control algorithm for the photovoltaic (PV) in a hybrid wind-PV system, in which the PV generatormay also need to work in a reduced power mode (RPM) to avoid dynamic overloading. The two control modes, MPPT and RPM, are inherently compatible and can be readily implemented, without the need of a dumping load for the RPM. Following the establishment of a dynamic system model, the study develops the guidelines to determine the variables of a direct hill-climbing method for MPPT: the perturbation time intervals and the magnitudes of the applied perturbations. These results are then used to optimally set up a variable-step size incremental conductance (VSIC) algorithm along with adaptive RPM control. The power tracking performance and power limiting capability are verified by simulation and experiment.

Maximum photovoltaic power tracking for the PV array using the fractional-order incremental conductance method

This paper proposes maximum photovoltaic power tracking (MPPT) for the photovoltaic (PV) array using the fractional-order incremental conductance method (FOICM). Since the PV array has low conversion efficiency, and the output power of PV array depends on the operation environments, such as various solar radiation, environment temperature, and weather conditions. Maximum charging power can be increased to a battery using a MPPT algorithm. The energy conversion of the absorbed solar light and cell temperature is directly transferred to the semiconductor, but electricity conduction has anomalous diffusion phenomena in inhomogeneous material. FOICM can provide a dynamic mathematical model to describe non-linear characteristics. The fractional-order incremental change as dynamic variable is used to adjust the PV array voltage toward the maximum power point. For a small-scale PV conversion system, the proposed method is validated by simulation with different operation environments. Compared with traditional methods, experimental results demonstrate the short tracking time and the practicality in MPPT of PV array.

Fourth-Order Buck Converter for Maximum Power Point Tracking Applications

Photovoltaic arrays (PVAs) need an intermediate maximum power point tracker as their v-i characteristics are nonlinear. Application of switch-mode dc-dc converters are popular in this area and the buck topology is widely used in these power tracking applications. However, the buck converter with an input L-C filter, with insufficient damping, will exhibit unwanted oscillations, or it may operate at suboptimal power points for certain solar insolations. Suitable damping must be designed otherwise the maximum power point (MPP) becomes unstable. Because of the variable impedance characteristic of PVA the design of optimal damping, suitable for all solar insolations, is a complex task. In order to eliminate these problems a fourth-order buck converter, which will track maximum power (MP) at all solar insolations, is proposed for the photovoltaic (PV) power tracking applications. Mathematical models of the proposed converter are formulated and then boundary conditions, under which the converter capable of tracking MP, are obtained. The combined PV power tracking scheme is simulated in PSIM and then power tracking performance characteristics are generated. Performance of the proposed topology is compared with the buck converter with input filter. The proposed converter effectiveness, in power tracking applications, is verified through experimental studies. Micro-controller, dsPIC30F6010, is employed in the real-time implementation of the perturb and observe (P & O) tracking algorithm.

Maximum photovoltaic power tracking: an algorithm for rapidly changing atmospheric conditions

As the maximum power operating point (MPOP) of photovoltaic (PV) power generation systems changes with changing atmospheric conditions (e.g. solar radiation and temperature), an important consideration in the design of efficient PV systems is to track the MPOP correctly. Many maximum power tracking (MPT) techniques have been considered in the past but techniques using microprocessors with appropriate MPT algorithms are favoured because of their flexibility and compatibility with different PV arrays. Although the efficiency of these MPT algorithms is usually high, it drops noticeably in cases of rapidly changing atmospheric conditions. The authors have developed a new MPT algorithm based on the fact that the MPOP of a PV generator can be tracked accurately by comparing the incremental and instantaneous conductances of the PV array. The work was carried out by both simulation and experiment, with results showing that the developed incremental conductance (IncCond) algorithm has successfully tracked the MPOP, even in cases of rapidly changing atmospheric conditions, and has higher efficiency than ordinary algorithms in terms of total PV energy transferred to the load.