Power loss due to soiling on solar panel: a review

The power output delivered from a photovoltaic module highly depends on the amount of irradiance, which reaches the solar cells. Many factors determine the ideal output or optimum yield in a photovoltaic module. However, the environment is one of the contributing parameters which directly affect the photovoltaic performance. The authors review and evaluate key contributions to the understanding, performance effects, and mitigation of power loss due to soiling on a solar panel. Electrical characteristics of PV (Voltage and current) are discussed with respect to shading due to soiling. Shading due to soiling is divided in two categories, namely, soft shading such as air pollution, and hard shading which occurs when a solid such as accumulated dust blocks the sunlight. The result shows that soft shading affects the current provided by the PV module, but the voltage remains the same. In hard shading, the performance of the PV module depends on whether some cells are shaded or all cells of the PV module are shaded. If some cells are shaded, then as long as the unshaded cells receive solar irradiance, there will be some output although there will be a decrease in the voltage output of the PV module. This study also present a few cleaning method to prevent from dust accumulation on the surface of solar arrays

Comparison of developed FLC and P&O MPPT algorithms for improving PV system performance at variable irradiance conditions

Purpose: This work aims to overcome the drawbacks of the nonlinear characteristics of the photo-voltaic (PV) system which are affected by the atmospheric variations. Design/methodology/approach: As a result, the optimum power point on these characteristics accordingly changes and the efficiency of photovoltaic systems reduces. Maximum power point tracking (MPPT) algorithms track this optimum point and enhance the efficiency despite the irradiance and temperature changes. Findings: The conventional perturbation and observation (P&O) algorithm uses fixed step sizes to increment and decrement the duty ratio that leads to slow response time and continuous oscillation around the MPP at steady state conditions. The paper proposes a fuzzy logic-based controller that overcomes the drawbacks of P&O algorithm in term of response time and the oscillation. Originality/value: MATLAB/Simulink environment was used to model and simulate the KC200GT PV module, direct current (DC)-DC boost converter and the MPPT algorithms

DC-DC converter for photovoltaic powered battery charger

Purpose: The purpose of this study is to show in power-voltage curve, a unique maximum power point (MPP) is existed which has the maximum power. Design/methodology/approach: This paper presents a MPP tracker algorithm for a standalone system includes DC-DC buck converter and battery storage. Findings: By using this algorithm, the maximum available power is achieved and simultaneously, the battery is charged and also protected against overcharge and discharge. The operation of the proposed algorithm is evaluated in with Proteus software to be sure that it can be implemented in microcontroller in reality. Originality/value: The simulations results show that the proposed algorithm is able to detect the MPP under different irradiations. Moreover, the battery is charged during the day by PV and protected against overcharge and discharge

Novel hybrid maximum power point tracking algorithm for PV systems under partially shaded conditions

Photovoltaic (PV) system has non-linear powervoltage (P-V) characteristic with single maximum power point (MPP) in uniform condition. The P-V curve would be more complicated during partially shaded (PS) conditions (PSCs) when multi-peak powers exist. The point with the highest value of power among the multi-peak powers is called global maximum power point (GMPP). In this paper, a novel hybrid method is proposed to obtain the GMPP in PSCs. In this method, if PS happens after reaching the MPP in uniform condition, the new operating point is specified based on modified linear function to reduce the searching zone and simultaneously the possible MPPs are recognized at the right side of the new obtained operating point. In the case where PS happens before reaching the MPP in uniform condition, the reference point is specified and then the location of GMPP is detected. Finally, after specifying the exact location of GMPP, the modified P&O is used to obtain the GMPP. To evaluate operation of the proposed method, simulation work has been carried out in MATLAB/Simulink where the GMPP is obtained in minimum time with high accuracy and minimum oscillation in power. Moreover, this method is not limited to any specific scenarios of shadowing

Evaluation of Fuzzy Logic Subsets Effects on Maximum Power Point Tracking for Photovoltaic System

Photovoltaic system (PV) has nonlinear characteristics which are affected by changing the climate conditions and, in these characteristics, there is an operating point in which the maximum available power of PV is obtained. Fuzzy logic controller (FLC) is the artificial intelligent based maximum power point tracking (MPPT) method for obtaining the maximum power point (MPP). In this method, defining the logical rule and specific range of membership function has the significant effect on achieving the best and desirable results. This paper presents a detailed comparative survey of five general and main fuzzy logic subsets used for FLC technique in DC-DC boost converter. These rules and specific range of membership functions are implemented in the same system and the best fuzzy subset is obtained from the simulation results carried out in MATLAB. The proposed subset is able to track the maximum power point in minimum time with small oscillations and the highest system efficiency (95.7%). This investigation provides valuable results for all users who want to implement the reliable fuzzy logic subset for their works

Implementing a Novel Hybrid Maximum Power Point Tracking Technique in DSP via Simulink/MATLAB under Partially Shaded Conditions

This paper presents a hybrid maximum power point tracking (MPPT) method to detect the global maximum power point (GMPP) under partially shaded conditions (PSCs), which have more complex characteristics with multiple peak power points. The hybrid method can track the GMPP when a partial shadow occurs either before or after acquiring the MPP under uniform conditions. When PS occurs after obtaining the MPP during uniform conditions, the new operating point should be specified by the modified linear function, which reduces the searching zone of the GMPP and has a significant effect on reducing the reaching time of the GMPP. Simultaneously, the possible MPPs are scanned and stored when shifting the operating point to a new reference voltage. Finally, after determining the possible location of the GMPP, the GMPP is obtained using the modified P&O. Conversely, when PS occurs before obtaining the MPP, the referenced MPP should be specified. Thus, after recognizing the possible location of the GMPP, the modified P&O can be used to obtain the GMPP. The simulation and experimental implementations for the proposed algorithm are performed with different scenarios of shadowing under different irradiations, which clearly indicate that the proposed method is robust and has a fast tracking speed. Moreover, this work presents the load sizing method for PSCs to avoid controller failure when detecting the GMPP. Additionally, in this paper, the user-friendly method for programming the digital signal processing (DSP) via Simulink/MATLAB is presented in detail

Dual search maximum power point algorithm based on mathematical analysis under partially-shaded conditions

Solar energy has drawn much attention in recent years because of high demand for green energy resources. Electrical power can be generated by using semiconductors in photovoltaic (PV) cells to convert solar irradiance into DC current. Each PV module has its own optimum point at which the power delivered from the PV is at its maximum value. Since the initial cost for using PV is high, it is essential to make the PV module to operate at its maximum power point (MPP). However, the non-linear relation between current and voltage for the PV system is a challengeable issue that results in a unique MPP for its power-voltage (P-V) curve. Under uniform conditions or without shading, there is a unique MPP on the P-V curve. By changing the irradiance and temperature, the value of MPP will be changed. The PV system is troubled with the weakness of nonlinearity between current and voltage under partially shaded conditions PSCs). Under PSCs, there are multi-peak powers. Only one of these peak powers has the highest power, which is called global maximum power point (GMPP), and other peak powers are the local maximum power point (LMPP).The maximum power point tracking (MPPT) algorithms under PSCs can be categorized generally in two groups. In the first group, the conventional techniques are combined with other techniques and the second group is based on the optimization methods. One of the main challenges of MPPT techniques under PSCs is ability of the algorithms to find the GMPP faster with minimal oscillation in power. Moreover, it is very important that the algorithms should be general and not so complicated which could be implemented for all systems.Therefore, this research presents design and development of a novel method, which is called dual search maximum power point (DSMPP) algorithm, for tracking the GMPP under PSCs. The proposed method is based on mathematical analysis that reduces the search zone and simultaneously identifies the possible MPPs in the specified zone that leads to determining the GMPP in minimum time. In this work, the perturb and observation (P&O) method based on duty cycle adjustment is introduced, which is modified to increase speed of the search and also to reduce the oscillation.The simulation and experimental works have been performed to investigate behavior and performance of the proposed algorithm. The PV array in series-parallel (SP)configuration is considered as an input of the standalone system and mathematical model of this PV array under PSC has been developed. Moreover, the load sizing method for PSCs is also presented to avoid controller failure when detecting the GMPP. In evaluation part, the DSMPP algorithm has been compared with two other methods.According to both simulation and experimental results, by implementing the DSMPP technique, the GMPP can be obtained faster. Moreover, the oscillation in power is reduced significantly. Interestingly, the experimental results under different irradiances also show that the proposed algorithm can detect the GMPP faster in comparison with other methods. The significant reduction of oscillation in power is observed to be due to implementation of the modified P&O.As a conclusion, the DSMPP algorithm has successfully been performed to detect the GMPP under PSCs in minimum time, with low oscillation in power, and high accuracy as detecting the GMPP for different scenarios of shadowing

Dual Search Maximum Power Point (DSMPP) Algorithm Based on Mathematical Analysis under Shaded Conditions

Photovoltaic (PV) systems represent a clean, renewable source of energy that has non-linear current-voltage (I-V) and power-voltage (P-V) characteristics. To increase the efficiency, a PV system must operate at the maximum power point (MPP) to produce the maximum available power. Under uniform conditions, there is only a single MPP in the P-V curve of a PV system; however, determining the MPP is more complicated under partially shaded conditions (PSCs) because multiple peak power points exist. In recent years, various studies have been performed to obtain the highest peak power point under PSCs, which is referred to as the global maximum power point (GMPP). In this paper, a novel method based on mathematical analysis that reduces the search zone and simultaneously identifies the possible MPPs in the specified zone is proposed; this proposed method is called the dual search maximum power point (DSMPP) algorithm. To evaluate the effectiveness of the proposed method, simulation and hardware implementations are carried out. The results show that the search time of GMPP is significantly reduced and the GMPP is detected in the minimum amount of time with high accuracy and minimum oscillation in the power produced

Evaluation of the 2013 Southeast Asian Haze on Solar Generation Performance.

Pollution in Southeast Asia is a major public energy problem and the cause of energy losses. A significant problem with respect to this type of pollution is that it decreases energy yield. In this study, two types of photovoltaic (PV) solar arrays were used to evaluate the effect of air pollution. The performance of two types of solar arrays were analysed in this research, namely, two units of a 1 kWp tracking flat photovoltaic (TFP) and two units of a 1 kWp fixed flat photovoltaic arrays (FFP). Data analysis was conducted on 2,190 samples at 30 min intervals from 01st June 2013, when both arrays were washed, until 30th June 2013. The performance was evaluated by using environmental data (irradiation, temperature, dust thickness, and air pollution index), power output, and energy yield. Multiple regression models were predicted in view of the environmental data and PV array output. Results showed that the fixed flat system was more affected by air pollution than the tracking flat plate. The contribution of this work is that it considers two types of photovoltaic arrays under the Southeast Asian pollution 2013