A novel hybrid MPPT technique for solar PV applications using perturb & observe and fractional open circuit voltage techniques

Solar photovoltaic (PV) systems have been an area of active research for the last few decades to improve the efficiency of solar PV module. The non-linear nature of IV curve of solar PV module demands some technique to track the maximum voltage and maximum current point on IV curve corresponding to Maximum Power Point(MPP). Thus, Maximum Power Point Tracking (MPPT) techniques are widely deployed for this purpose. Lot of MPPT techniques have been developed in recent past but still most commercial systems utilizes the perturb & observe (P&O) MPPT technique because of its simple algorithm, low cost and ease of implementation. However, this technique is slow in tracking MPP under rapidly changing irradiance conditions and it also oscillates around the MPP. This paper addresses this problematic behavior of P&O technique and hence presents a novel MPPT hybrid technique that is combination of two basic techniques i.e. P&O and Fractional Open Circuit Voltage (FOCV) technique in order to overcome the inherited deficiencies found in P&O technique. The proposed MPPT technique is much more robust in tracking the MPP even under the frequent changing irradiance conditions and is less oscillatory around the MPP as compared to P&O. The technique is verified using MATLAB/SIMULNK and simulation results show a clear improvement in achieving the MPP when subjected to change in irradianc

A New Sensorless Hybrid MPPT Algorithm Based on Fractional Short-Circuit Current Measurement and P&O MPPT

This paper presents a new maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The proposed method improves the working of the conventional perturb and observe (P&O) method in changing environmental conditions by using the fractional short-circuit current (FSCC) method. It takes the initial operating point of a PV system by using the short-circuit current method and later shifts to the conventional P&O technique. The advantage of having this two-stage algorithm is rapid tracking under changing environmental conditions. In addition, this scheme offers low-power oscillations around MPP and, therefore, more power harvesting compared with the common P&O method. The proposed MPPT decides intelligently about the moment of measuring short-circuit current and is, therefore, an irradiance sensorless scheme. The proposed method is validated with computer software simulation followed by a dSPACE DS1104-based experimental setup. A buck-boost dc-dc converter is used for simulation and experimental confirmation. Furthermore, the reliability of the proposed method is also calculated. The results show that the proposed MPPT technique works satisfactorily under given environmental scenarios

A novel hybrid MPPT technique for solar PV applications using perturb & observe and fractional open circuit voltage techniques

Solar photovoltaic (PV) systems have been an area of active research for the last few decades to improve the efficiency of solar PV module. The non-linear nature of IV curve of solar PV module demands some technique to track the maximum voltage and maximum current point on IV curve corresponding to Maximum Power Point(MPP). Thus, Maximum Power Point Tracking (MPPT) techniques are widely deployed for this purpose. Lot of MPPT techniques have been developed in recent past but still most commercial systems utilizes the perturb & observe (P&O) MPPT technique because of its simple algorithm, low cost and ease of implementation. However, this technique is slow in tracking MPP under rapidly changing irradiance conditions and it also oscillates around the MPP. This paper addresses this problematic behavior of P&O technique and hence presents a novel MPPT hybrid technique that is combination of two basic techniques i.e. P&O and Fractional Open Circuit Voltage (FOCV) technique in order to overcome the inherited deficiencies found in P&O technique. The proposed MPPT technique is much more robust in tracking the MPP even under the frequent changing irradiance conditions and is less oscillatory around the MPP as compared to P&O. The technique is verified using MATLAB/SIMULNK and simulation results show a clear improvement in achieving the MPP when subjected to change in irradianc

An intelligent off-line MPPT technique for PV applications

Harnessing energy from the abundant and free sunlight is now a days a hot topic among the research community. The availability of cheap solar modules has made it possible to harvest solar energy with better efficiency. The nature of solar modules is non linear and therefore the process of impedance matching is essential. The proper impedance matching ensures extraction of the maximum power from solar PV module. Several algorithms are reported in literature that are used to operate the DC-DC converter around Maximum Power Point (MPP). Among those algorithms off-line techniques are considered the easiest to implement. However, intermittent measurement of Short Circuit Current (SCC)/Open Circuit Voltage (OCV) results in the power loss. The decision about the measurement of SCC/OCV is often based on the irradiance/temperature sensors. In this paper we propose a modified algorithm for off-line MPPT techniques. The proposed technique decides intelligently about the measurement of SCC/OCV. The technique is modeled and simulated in Matlab/Simulink and the results shows satisfactory performance against test conditions

Pakistan’s progress in solar PV based energy generation

Solar PV has been a cornerstone for the energy policy makers around the globe. It is because the environmental effects of solar energy are low as compared to the conventional energy sources. It is free and virtually inexhaustible. Developed countries have long been in the business of using solar energy for energy generation. However, for the third world countries like Pakistan, the use of solar energy for power generation is a relatively new experience. In recent months, Pakistan has shown a paradigm shift in its renewable energy policy and invested on mega power plants based on solar PV system. This paper reviews the recent exponential rise of using solar energy for power generation in Pakistan. The results of this paper will not only help in understanding and hence, curbing the power crisis in Pakistan, but will also be relevant to the other countries of the third world

A two stage hybrid maximum power point tracking technique for photovoltaic applications

Photovoltaic (PV) systems are widely used now a days for coping the growing energy demands all across the globe. The non-linear behavior of the characteristic curve of solar module requires special arrangement to harvest maximum amount of power. To track the Maximum Power Point (MPP) across the non linear IV curve of PV module, techniques are used in addition to the power electronic circuit and are called Maximum Power Point Tacking (MPPT). Various methods of MPPT exists in literature, each bearing its own pros and cons. In this paper we presents a novel technique to improve the performance of conventional Perturb and Observe (P&O) algorithm of MPPT. Our technique removes the drawbacks of P&O under rapidly changing environmental conditions. It also executes less power oscillations under steady state conditions. The algorithm is a hybrid of Fractional Short Circuit current (FSCC) and P&O algorithms. The system takes the advantage of rapid tracking near to MPP using the FSCC and then carry on to track the exact MPP using the traditional P&O technique. The technique is verified through simulation using Matlab/SIMULINK

A new irradiance sensorless hybrid MPPT technique for photovoltaic power plants

A hybrid Maximum Power Point Tracking (MPPT) method without using an irradiance sensor is proposed in this paper. The hybrid MPPT method is a combination of conventional Perturb and Observe (P&O) and Fractional Short Circuit Current (FSCC) MPPT technique. The proposed hybrid MPPT decides intelligently about the initial operating point of P&O by using the FSCC MPPT method. This method requires no sensor for irradiation measurement because it detects intelligently about the change in irradiance. Therefore, under dynamic weather conditions the decision about measuring the initial operating point of P&O is intelligent. After finding the initial operating point the system shifts to the conventional P&O method and starts to perturb with a small perturbation size. The use of small perturbation steps enables the system to work with less power oscillations around the Maximum Power Point (MPP), while the use of FSCC helps in rapid tracking of MPP especially under the varying environmental conditions. Thus, the proposed method is fast in tracking the MPP with less power oscillations and hence better performance in terms of energy harvesting when compared with the conventional P&O technique. Impedance matching between solar panel and load is achieved using a DC-DC boost converter and the proposed method is simulated in MATLAB/SIMULINK environment. The system is simulated against the steady and dynamic weather conditions. The results shows that under steady weather condition the proposed method harvests 5% extra energy as compared with the conventional P&O. For dynamic weather conditions the proposed method harness an additional 3.5% energy when compared with the P&O method, which makes it very promisin

Optimization of the perturb and observe maximum power point tracker for a distributed photovoltaic system

With everyday passing, power generation from photovoltaic (PV) systems are getting increased around the globe. One of the drawbacks of PV systems is that they exhibit non-linear I-V curves with respect to atmospheric conditions. Therefore, maximum power point tracker (MPPT) technique is installed in every PV system. One of the most popular technique is perturb & observe (P&O) but this technique has some shortcomings. In this paper, MPPT technique is proposed which will optimize the P&O with respect to distributed PV (DPV) plant. Such that the deficiencies of P&O are removed. The proposed technique is designed for DPV and is working in two modes. In mode-1, decision making of the proposed technique revolves around the mutual co-ordination between two modules/arrays. During this mode, one array will behave as leader (L) while other array as follower (F). In mode-2, proposed technique utilizes the individual P&O for both arrays. Model is the superior performance mode in which efficiency of the proposed technique is better than P&O. While, in mode-2 both techniques have same efficiency. Finally, the proposed technique is modeled in Matlab/Simulink. The proposed technique is tested under various weather conditions and superior performance of the proposed technique is proved through simulation results