A review study of photovoltaic array maximum power tracking algorithms
Renewables: Wind, Water, and Solar volume 3, Article number: 3 (2016)
There are numerous maximum power point tracking (MPPT) algorithms for improving the energy efficiency of solar photovoltaic (PV) systems. The main differences between these algorithms are digital or analog implementation, simplicity of the design, sensor requirements, convergence speed, range of effectiveness, as well as hardware costs. Therefore, choosing the right algorithm is very important to the users, because it affects the electrical efficiency of PV system and reduces the costs by decreasing the number of solar panels needed to get the desired power. This paper provides the comparison of 62 different techniques used in tracking the maximum power based on literature survey. This paper is intended to be a reference for PV systems users.
Recently, renewable energy technology has been swiftly developed where it has an important role in clean energy application. An important type of renewable energy is solar energy that produces electrical energy directly using PV modules supported by MPPT algorithm to maximize the output power. The objective of obtaining MPP in PV systems is to regulate the actual operating voltage of PV panels to the voltage at MPP, by adjusting the output power of the inverter (Libo et al. 2007).
In literature, there are plentiful MPPT methods as in (Esram and Chapman 2007; Ali et al. 2012; Jusoh et al. 2014; Kamarzaman and Tan 2014; Liu et al. 2015; Lyden and Haque 2015). Kamarzaman and Tan (2014) used four categories to review MPPT algorithms as follows: conventional MPPT algorithms (perturb and observation P&O and incremental conductance IC); hill-climbing (open circuit voltage and short circuit current); ripple correlation current; and stochastic-based MPPT algorithms (particle swarm optimization, fuzzy logic controller, artificial neural network, and differential evolution). Liu et al. (2015) gave a review of MPPT techniques for use in partially shaded conditions. Lyden et al. (2015) divided the tracking techniques to three types: conventional MPPT techniques, global MPPT techniques, and power electronics-based approaches.
This paper presents a brief comparison between different techniques to help the users to choose an MPPT technique for a particular application. The comparison between the MPPT methods includes cost, analog or digital implementation, sensor dependence, convergence speed, hardware complexity, and effectiveness.
Second section illustrates the statement of the problem. Comparison between different MPPT techniques is given in third section. In fourth section, the methodology is presented followed by the fifth section in which results are introduced and three most popular algorithms are presented. Finally, the conclusion is presented in the last section.
Statement of the problem
In medium- and large-scale systems, sun tracking or MPPT or both are used to obtain maximum power (Tse et al. 2002). MPPT systems are considered the most popular in all PV systems. MPPT systems are used to reach MPP automatically from solar modules. That is the PV system will work at its maximum efficiency. The amount of energy gained by PV system depends on several factors including level of irradiance, temperature, and partial shading. Thus, these algorithms should consider the changes in these factors. The characteristic current–voltage curve and power–voltage curve are displayed in Fig. 1. These characteristic curves present the parameters that describe the operation of the PV cell such as the open-circuit voltage V OC , short circuit current I SC , and the cell voltage, current, and power at the maximum power point, V MPP , I MPP , and P MPP , respectively.
In addition, the fill factor FF and efficiency η are considered. FF measures the quality of the PV array. It is the ratio of the actual MPP (P MAX ) to the product of V OC and I SC as in (1) (Chen 2011).
While the efficiency, η, of a solar cell is defined as the ratio of the output electric power over the input solar radiation power under standard illumination conditions at the maximum power point (Chen 2011).
Comparison between MPPT techniques
The MPPT techniques vary in many aspects, which might help the users to decide the system that suits their unique applications. These parameters include hardware implementation, sensor, convergence speed, multiple local maximum, cost, application, and dependency on array parameter. Hardware implementation is simply the type of circuit: analog or digital (Esram and Chapman 2007). Sensors and their numbers affect the decision makers to decide which MPPT to use. The more precise MPPT requires more sensors (Reported issued by National Instruments 2009). Usually, it is easier to sense voltage than current. The irradiance or temperature sensors are very expensive and uncommon (Faranda and Leva 2008).
Convergence speed is the time taken to reach the MPP (Walker et al. 2011). For a high-performance MPPT system, the time taken to converge to the required operating voltage or current should be low. The lower time and periodic tuning taken to reach the MPP minimize power losses and maximize efficiency.
The ability to detect multiple local maxima when the system is under different irradiance levels is another important parameter. The power loss can reach 70 % under partial shading condition, if a local maximum is tracked instead of the real MPP (Reported issued by National Instruments 2009; Ji et al. 2009).
Performance cost is another parameter that concerns the users. It is usually cheaper to use analog system than digital system. Moreover, the number and type of sensors, using other power or electronic components, add extra cost to the system (Faranda and Leva 2008).
Different MPPTs are suitable for various applications. Depending on the application, different aspects may be considered important when choosing the PV system. As an example, in space satellites and orbital stations applications that involve a large amount of money, the costs and complexity of the MPP tracker are not as important as its performance and reliability. The tracker should be able to continuously track the true MPP in minimum amount of time and should not require periodic tuning (Khatib et al 2010).
The MPPT system might be independent (direct) or dependent (indirect) on array parameters. The direct methods use PV voltage and/or current measurements. These direct methods have the advantage of being independent from the prior knowledge of the PV array configuration and parameter values for their implementation. Thus, the operating point is independent of irradiance, temperature, or degradation levels. The indirect methods are based on the use of a database of parameters that include data of typical P–V curves of PV systems for different irradiances and temperatures, or on the use of mathematical functions obtained from empirical data to estimate the MPP (Khatib et al. 2010; Jain and Agarwa 2007). Table 1 summarizes the most important characteristics of MPPT algorithm that is used to compare between different techniques.
In this work, we conducted a literature review to what is available in terms of MPP tracking algorithms. We analyzed theoretically the work presented in each paper and fetch the parameters as indicated in Table 1. We collected 45 different algorithms. The differences between 45 MPPT algorithms are listed in Table 2. Table 2 is an extended work to what have been presented in (Ali et al. 2012). Further, algorithms are collected from other resources.
The comparison between 62 algorithms is shown in Table 2. According to the table, the most common algorithms are perturb and observe (P&O)/”hill-climbing,” incremental conductance algorithm, and fuzzy logic controller (FLC).
Below is a quick review of these three well-known algorithms.
Perturb and Observe (P&O)/”hill-climbing”
The P&O is the most popular for its low cost, ease of implantation, simple structure, and few measured parameters, which are required. It only measures the voltage (V) and current (I) of the PV array. PV system controller changes PV array output with a smaller step in each control cycle. The step size is generally fixed, while mode can be increased or decreased. Both PV array output voltage and output current can be the control object; this process is called “perturbation.” It depends on the fact that the derivative of power with respect to voltage is zero at MPP point (Sera et al. 2006; Busa et al. 2012). This method fails under rapidly changed atmospheric conditions and has a slow response speed oscillation around the MPP (Sera et al. 2006).
Incremental conductance algorithm
The incremental conductance method is based on the fact that the sum of the instantaneous conductance (I/V) and the incremental conductance is zero at MPP. Figure 2 shows the slope of the PV array power curve compared to (I/V). Thus, incremental conductance can determine that the MPPT has reached the MPP and stop perturbing the operating point of the PV array as explained in Fig. 2.
Although incremental conductance is an improved version of P&O, it can track rapidly increasing and decreasing irradiance conditions with higher accuracy than P&O. However, this algorithm is more complex than P&O. This increases computational time and slows down the sampling frequency of the array voltage and current (Esram and Chapman 2007; Chen 2011; Yadav et al. 2012; Rashid 2011; Zainudin and Mekhilef 2010).
Fuzzy logic controller (FLC)
FLC consists of four categories as fuzzification, inference engine, rule base, and defuzzification. The numerical input variables are converted into fuzzy variable known as linguistic variable based on a membership function similar to Fig. 3. In this case, five fuzzy levels are used: NB (negative big), NS (negative small), ZE (zero), PS (positive small), and PB (positive big). For more accuracy seven fuzzy levels are used. In Fig. 3, a and b are based on the range of values of the numerical variable. Conventional fuzzy MPPT consists of two inputs and one output. The two input variables are the error (E) and the error change (ΔE), at sampled times k. The input E (k) shows if the load operation point at the instant k is located on the left or on the right of the maximum power point on the PV characteristic, while the input ΔE(k) expresses the moving direction of this point (Esram and Chapman 2007; Ali et al. 2012; Faranda and Leva 2008; Brito et al. 2013).
In this work, we presented a comparison of 62 MPPT algorithms. In the comparison, we used several parameters including the complexity of the system, number of sensors, kind of circuitry (digital or analog), tuning, convergence speed, and the dependency of the parameters. The results are shown in the table to serve the users to choose the suitable system that suits their specific applications. Moreover, we presented a summary of three most common MPPT algorithms.
Abdalla, I., Zhang, L., & Corda, J. (2011). “Voltage-Hold Perturbation & Observation Maximum Power Point Tracking Algorithm (VH-P&O MPPT) for Improved Tracking over the Transient Atmospheric Changes,” presented at Power Electronics and Applications (EPE 2011) of the 2011-14th European Conference, (pp.1–10).
Abdulmajeed, Q. M., Kazem, H. A., Mazin, H., Abd Malek, M. F., Maizana, D., Alwaeli, A. H. A., Albadi, M. H., Sopian, K., & Said Al Busaidi, A. (2013). “Photovoltaic maximum tracking power point system: review and research challenges,” International Journal of Advanced Trends in Computer Science and Engineering (IJATCSE), Vol. 2, No. 5. (pp.16–21).
Ali, A., Saied, M., Mostafa, M., & Moneim, T. (2012). A survey of maximum PPT techniques of PV Systems. Energytech, 2012 IEEE.
Amrouche, B., Belhamel, M., & Guessoum, A. (2007). ”Artificial intelligence based P&O MPPT method for photovoltaic systems,” Revue des Energies Renouvelables ICRESD, Vol. 7, (pp. 11–16).
Azab, M. (2008). A new maximum power point tracking for photovoltaic systems. World Academy of Science, Engineering and Technology, 44, 571–574.
Brito, M., Galotto, L., Sampaio, L., Melo, G., & Canesin, C. (2013). Evaluation of the Main MPPT Techniques for Photovoltaic Applications. IEEE Transactions on Industrial Electronics, 60(3), 1156–1167.
Busa, V., Narsingoju, K. K., & Kumar, G. V. (2012). Simulation analysis of maximum power control of photo voltaic power system. International Journal on Advanced Electrical and Electronics Engineering (IJAEEE), 1(1), 9–14.
Chen, C. J. (2011). Physics of solar energy. New Jersey: Wiley.
Coelho, R., Concer, F., & Martins, D. (2010). ”A MPPT Approach Based on Temperature Measurements Applied in PV Systems,” IEEE/IAS International Conference on Industry Applications, (pp. 1–6).
Esram, T., & Chapman, P. (2007). Comparison of photovoltaic array maximum power point tracking techniques. IEEE Transactions on Energy Conversion, 22(2), 439–449.
Faranda, R., & Leva, S. (2008a). Energy comparison of MPPT techniques for PV systems. Wseas Transaction on Power Systems, 3, 446–455.
Faranda, R., & Leva, S. (2008b). Energy comparison of MPPT techniques for PV systems. Wseas Transaction on Power Systems, 3, 446–455.
Ghazanfari, J., & Farsangi, M. (2013). Maximum power point tracking using sliding mode control for photovoltaic array. Iranian Journal of Electrical & Electronic Engineering, 9(3), 189–196.
Go, S., Ahn, S., Choi, J., Jung, W., Yun Yun, S., & Song, II. “Simulation and Analysis of Existing MPPT Control Methods in a PV Generation System.” Journal of International Council on Electrical Engineering, Vol. 1, No. 4, pp. 446-451, 2011.
Hohm, D. P., & Ropp, M. E. (2003). ”Comparative Study of Maximum Power Point Tracking Algorithms,” Progress in Photovoltaic: Research and Application, (pp. 47–62).
Hu, J., Zhang, J., & Wu, H. (2009). “Novel MPPT control algorithm based on numerical calculation for PV generation systems,” presented at Power Electronics and Motion Control Conference (pp. 2103–2107). China: Baoding.
Israel, J. (2015). “Summary of maximum power point tracking methods for photovoltaic cells,” electronic matter, retrieved on May 2015.
Jain, S., & Agarwa, V. (2007). Comparison of the performance of maximum power point tracking schemes applied to single-stage grid-connected photovoltaic systems. The Institution of Engineering and Technology Power Appl., 1(5), 753–762.
Ji, Y. H., Jung, D. Y., Won, C. Y., Lee, B. K., & Kim, J. W. (2009). Maximum power point tracking method for PV array under partially shaded condition. Energy Conversion Congress and Exposition, 2009. ECCE 2009. IEEE. (pp. 307–312).
Jiang, J., Huang, T., Hsiao, Y., & Chen, Ch. (2005). Maximum power tracking for photovoltaic power systems. Tamkang Journal of Science and Engineering, 8(2), 147–153.
Jusoh, A., Sutikno, T., Guan, T. K., & Mekhilef, S. (2014). A Review on favourable maximum power point tracking systems in solar energy application. Telkomnika, 12(1), 6–22.
Kamarzaman, N., & Tan, C. W. (2014). A comprehensive review of maximum power point tracking algorithms for photovoltaic systems. Renewable and Sustainable Energy Reviews, 37, 585–598.
Khatib, T. T. N., Mohamed, A., & Amim, N. (2010). An improved indirect maximum power point tracking method for standalone photovoltaic systems,” presented at Proceedings of the 9th WSEAS International Conference on Applications of Electrical Engineering, Selangor, Malaysia, pp. (56–62).
Kulaksiz, A., & Akkaya, R. (2012). Training data optimization for ANNs using genetic algorithms to enhance MPPT efficiency of a stand-alone PV system. Turk J Elec Eng and Comp Sci, 20(2), 241–254.
Kumar, Ch., Dinesh, T., & Babu, S. (2013). Design and Modelling of PV System and Different MPPT Algorithms. International Journal of Engineering Trends and Technology (IJETT), 4, 4104–4112.
Kumari, J., & Babu, Ch. (2011). Comparison of maximum power point tracking algorithms for photovoltaic system. International Journal of Advances in Engineering and Technology, 1, 133–148.
Lapeña, O., Penella, M., & Gasulla, M. (2010). A New MPPT Method for Low-Power Solar Energy Harvesting. IEEE Transactions on Industrial Electronics, 57(9), 3129–3138.
Lee, J. (2011). Advanced electrical and electronic engineering. Berlin: Springer.
Lee, J. S., & Lee, K. B. (2013). Variable DC-link voltage algorithm with a wide range of maximum power point tracking for a two-string PV System. Energies, 6, 58–78.
Leyva, R., Olalla Martinez, C., Zazo, H., Cabal, C., Cid-Pastor, A., Queinnec, I., & Alonso, C. (2012). “MPPT Based on Sinusoidal Extremum-Seeking Control in PV Generation,”. International Journal of Photoenergy, 2012, 1–7.
Libo, W., Zhengming, Z., & Jianzheng, L. (2007). A single-stage three-phase grid-connected photovoltaic system with modified MPPT method and reactive power compensation. IEEE Transactions on Energy Conversion, 22(4), 881–886.
Liu, Y., Chen, J., & Huang, J. (2015). A review of maximum power point tracking techniques for use in partially shaded conditions. Renewable and Sustainable Energy Reviews, 41, 436–453.
Liu, C., Wu, B., & Cheung R. (2004). “Advanced Algorithm for MPPT Control of Photovoltaic System,” presented at Canadian Solar Buildings Conference, Montreal.
Lyden, S., & Haque, M. E. (2015). ” Maximum Power Point Tracking techniques for photovoltaic systems: A comprehensive review and comparative analysis,” Vol. 52, (pp.1504–1518).
Mandour, R., & Elamvazuthi, I. (2013). Optimization of maximum power point tracking (MPPT) of photovoltaic system using artificial intelligence (AI) algorithms.” Journal of Emerging Trends in Computing and Information Sciences, Vol. 4, No. 8.
Mastromauro, R., Liserre, M., & Aquila, A. (2012). Control issues in single-stage photovoltaic systems: MPPT, current and voltage control. IEEE Transactions on Industrial Informatics, 8(2), 241–254.
Morales, D. S. (2010). “Maximum power point tracking algorithms for photovoltaic applications, “A thesis presented to the faculty of electronics. Communications and Automation: Aalto University, Finland.
Qiang, F., & Nan, T. (2013). A Strategy Research on MPPT Technique in Photovoltaic Power Generation System. Telkomnika, 11(12), 7627–7633.
Rahman, Md, Poddar, S., Mamun, M., Mahmud, S., & Yeasin, Md. (2013). Efficiency comparison between different algorithms for maximum power point tracker of a solar system. International Journal of Scientific Research and Management (IJSRM), 1, 157–167.
Rahmani, R., Seyedmahmoudian, M., Mekhilef, S., & Yusof, R. (2013). Implementation of fuzzy logic maximum power point tracking controller for photovoltaic system. American Journal of Applied Sciences, 10, 209–218.
Rashid, M. H. (2011). Power Electronic Handbook (3rd ed.). USA: Butterworth-Heinemann.
Reisi, A., Moradi, M., & Jamasb, S. (2013). Classification and comparison of maximum power point tracking techniques for photovoltaic system: A review. Renewable and Sustainable Energy Reviews, 19, 433–443.
Rekioua, D., & Matagne, E. (2012). Optimization of photovoltaic power systems modelization, simulation and control. London: Springer.
Reported issued by National Instruments. (2009). Maximum power point tracking. http://www.ni.com/white-paper/8106/en.
Rezaei, A., & Gholamian, S. A. (2013). Optimization of New Fuzzy Logic Controller by Genetic Algorithm for Maximum Power Point Tracking in Photovoltaic System. Journal of Science and Technology, 9(1), 9–16.
Rodriguez, C., & Amaratunga, G. (2007). Analytic solution to the photovoltaic maximum power point problem. IEEE Transactions on Circuits and System, 54(9), 2054–2060.
Sera, D., Kerekes, T., Teodorescu, R., & Blaabjerg, F. (2006a). Improved MPPT algorithms for rapidly changing environmental conditions presented at Power Electronics and Motion Control Conference, 2006. EPE-PEMC, 2006, 1614–1619.
Sera, D., Kerekes, T., Teodorescu, R., & Blaabjerg, F. (2006b). “Improved MPPT Algorithms for Rapidly Changing Environmental Conditions,” presented at Power Electronics and Motion Control Conference, 2006. EPE-PEMC, 2006, 1614–1619.
Takun, P., Kaitwanidvilai, S., & Jettanasen, C. (2011)“Maximum power point tracking using fuzzy logic control for photovoltaic systems,” presented at International Multi Conference of Engineers and Computer Scientists, Hong Kong, Vol. 2.
Tse, K. K., Ho, M. T., Chung, H. S.-H., & Hui, S. Y. (2002). “A novel maximum power point tracker for PV panels using switching frequency modulation,”. IEEE Transactions on Power Electronics, 17(6), 980–989.
Vladimir V. R., Scarpa, S., Buso, G., & Spiazzi. (2009). “Low-complexity MPPT technique exploiting the PV module MPP locus characterization.” IEEE Transactions on Industrial Electronics, Vol. 56, No. 5.
Walker, S., Sooriyaarachchi, N., Liyanage, N., Abeynayake, P., & Abeyratne, S. (2011). Comparative analysis of speed of convergence of MPPT techniques. presented at 6th International Conference on Industrial and Information Systems, Sri Lanka, (pp. 522–526).
Walker, S., Sooriyaarachchi, N., Liyanage, N., Abeynayake, P., & Abeyratne, S. (2011)”Comparative Analysis of Speed of Convergence of MPPT Techniques,” presented at 6th International Conference on Industrial and Information Systems, Sri Lanka, (pp. 522-526).
Xiao, W., Dunford, W., Palmer, P., & Capel, A. (2007). Application of centered differentiation and steepest descent to maximum power point tracking. IEEE Transactions on Industrial Electronics, 54(5), 2539–2549.
Yadav, A., Thirumaliah, S., & Haritha, G. (2012). Comparison of MPPT algorithms for DC–DC converters based PV systems. International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering, 1, 18–23.
Yafaoui, A., Wu, B., & Cheung, R. (2007). ” Implementation of Maximum Power Point Tracking Algorithm For Residential Photovoltaic Systems,” presented at 2nd Canadian Solar Buildings Conference, Calgary.
Yang, Y., & Yan, Z. (2013). A MPPT method using piecewise linear approximation and temperature compensation. Journal of Computational Information Systems, 9(21), 8639–8647.
Zainudin, H., & Mekhilef, S. (2010). “Comparison study of maximum power point tracker techniques for PV systems,” presented at international middle east power systems conference (MEPCON’10) (pp. 750–755). Egypt: Cairo University.
Zazo, H., Leyva, R., & Castillo, E. (2012). “Analysis of Newton-Like Extremum Seeking Control in Photovoltaic Panels,” presented at International Conference on Renewable Energies and Power Quality (ICREPQ‘12), Santiago de Compostela, Spain.
Zhou, L., Chen, Y., Liu, Q., & Wu, J. (2012). Maximum power point tracking (MPPT) control of a photovoltaic system based on dual carrier chaotic search. J Control Theory Appl, 10(2), 244–250.
HJE and TS originated the problem idea. KM collected and demonstrated the idea. RE contributed in writing and reviewing the paper. All authors read and approved the final manuscript.
The authors declare that they have no competing interests.
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El-Khozondar, H.J., El-Khozondar, R.J., Matter, K. et al. A review study of photovoltaic array maximum power tracking algorithms. Renewables 3, 3 (2016). https://doi.org/10.1186/s40807-016-0022-8