Prototype Of Photovoltaic System Research Articles

MPPT Operation Performance of Automotive Photovoltaic System during Driving

In this study, an automotive photovoltaic (PV) system was fabricated for electric vehicles. The PV panel for the PV system prototype comprises modules. Each module is equipped with a converter for maintaining maximum power point tracking (MPPT) operation. This configuration allows performing the MPPT operation individually for each PV module. Furthermore, the MPPT operation performance during driving was verified. The PV system prototype maintained power generation during driving using the MPPT operation. In situations where the solar radiation varies frequently, the range of the MPPT voltage search influences the tracking achievement ratio (TAR). In addition, a TAR of 97% was achieved by optimizing the range of the MPPT voltage search.

Performance analysis of polycrystalline floating photovoltaic array: The concept and prototype development for irrigation purpose

AbstractThe concept and design of the 2 kWp polycrystalline floating photovoltaic (PV) system for agricultural irrigation purposes are presented in this paper. The well‐known major advantage of the floating PV system is its installation in the presence of water, which leads to cooling of the PV system that improves its efficiency. In addition to that, the floating PV system reduces the wastage of cultivation area required for its installation, and also, it reduces evaporation of water (for 20% of float cover) by the factor of 22.23 cm/year. But the floating PV systems face some confrontations such as low electrical reliability and reduced life of the mechanical structure due to nearby water surface. As an attempt to overcome the above issues, a small‐scale floating PV system prototype in a water reservoir at Kothavadi village, Tamil Nadu, India has been developed. The system comprises of a floater, mechanical structure, PV module, supporting anchor, under water cable, and motor. The power generated out of this proposed system is utilized for pumping the water from a nearby bore well, and pumped water is stored in the same reservoir where the floating PV system is installed. The water in the reservoir can be used by the farmer for their necessity. In this study, the energy production (month by month) is monitored. Furthermore, the economic analysis and PV modeling have been performed along with some maintenance aspects. The study helps the scientists and engineers to comprehend the performance and commercial viability of floating PV for rural farmers. It is anticipated that this work will inspire and direct farmers to install a floating PV irrigation system as a perfect alternate for the conventional systems.

Prototype of photovoltaic system with dual axis tracker and flat mirror concentrators

Use of a solar tracker and concentrator of solar radiation flow is distinguished among the most efficient ways to improve electric efficiency of a photovoltaic system. The aim of the research is to detect the effect of each of the ways to improve efficiency of photovoltaic system by comparing installations of different structure (stationary oriented panel, a panel with two-axis tracker and a panel with two-axis tracker and flat mirror concentrator). Basing on the carried analysis of the existing constructions of solar tracking systems, the research substantiates structure of the studied prototype, which moves around the polar axis in a day cycle of tracking, and makes a change of the zenith in a seasonal cycle of the system operation. To secure the function of solar tracking by a photovoltaic panel the research has developed a construction, an algorithm and a program of intellectual microprocessing control system, which supplies tracking of azimuth and zenith angles and protection of the tracker from destruction in case of stormy winds. To argue size dimensions and profile of the principal elements of the tracker construction, the researchers have developed a virtual 3D model and proposed a kinematic-constructive scheme of a rotation gear drive. The work proposes methods of automation of a comparative examination of photovoltaic systems with different structural scheme, which are based on the hardware platform Arduino and software LabVIEW of the company National Instruments.

Direct Connection of Supercapacitor–Battery Hybrid Storage System to the Grid-Tied Photovoltaic System

Penetration rate of grid-connected photovoltaic (PV) generation to the existing utility grid is rapidly increasing over the years. Since the power generated from PV systems fluctuates according to the weather condition, e.g., cloud passing, this can significantly disturb the stability of a weak utility grid. The integration of energy storage devices and its ramp-rate control technique are required to reduce the impact of PV systems output fluctuations and augment the stability of the utility grid. In this paper, ramp-rate control is applied to the direct connection of energy storage devices in PV generation system configuration. The direct connection of supercapacitors string and battery combination scheme is proposed to reduce the number of power converters so that the efficiency of the system is increased. In this work, the PV system output is controlled by directly controlling the energy storage system (ESS) to limit the changing rate of the PV output to a desired ramp-rate value, hence reducing the battery charge/discharge cycles and extending the expected lifetime of the ESS. The performance of the proposed direct connection scheme of the ESS and its ramp-rate control strategy is verified using a 1-kW PV system prototype.

Adaptive pseudo‐linear control for grid‐supportive PV system

This work demonstrates a grid-supportive photovoltaic (PV) system with an adaptive pseudo-linear control. The proposed PV system utilises a boost converter and a voltage source converter (VSC). The VSC performs multitasks such as load balancing, harmonics suppression and enhancing active power penetration to the grid. Wherein, a perturb and observe based technique serves the function of maximum power point tracking through the control of a boost converter. However, an adaptive pseudo-linear control is used for control of VSC. The adaptive pseudo-linear algorithm is used for the evaluation of fundamental components of load currents and it estimates the reference grid currents. The grid currents are controlled to generate the insulated gate bipolar transistors firing signals for VSC. A prototype of PV system is developed in the laboratory and implemented under different loads and solar insolation levels. The total harmonic distortions of grid currents are preserved within the limits in accordance with the IEEE-519 standard.

PV System Control to Provide Active Power Reserves Under Partial Shading Conditions

The challenges of modern power systems will inevitably impose increased ancillary service requirements to photovoltaic (PV) plants in the future, including operating reserves. Recent studies have investigated methods to maintain active power reserves without energy storage in the standard case of uniform illumination. In this paper, this functionality is extended to partial shading conditions, often encountered in PV systems. A new control scheme is proposed that permits operation at a reduced power level, estimating at the same time the shading conditions and maximum available power. This is achieved by applying a least-squares curve fitting algorithm on voltage and current measurements, without relying on any irradiance or temperature sensors. To the best of our knowledge, this is the first power reserves control scheme for PV systems under partial shading presented in the literature. The robustness and effectiveness of the proposed method are validated under rapidly changing shading conditions through simulations and experimental tests on a 2-kW PV system prototype.

A High-Performance Adaptive Incremental Conductance MPPT Algorithm for Photovoltaic Systems

The output characteristics of photovoltaic (PV) arrays vary with the change of environment, and maximum power point (MPP) tracking (MPPT) techniques are thus employed to extract the peak power from PV arrays. Based on the analysis of existing MPPT methods, a novel incremental conductance (INC) MPPT algorithm is proposed with an adaptive variable step size. The proposed algorithm automatically regulates the step size to track the MPP through a step size adjustment coefficient, and a user predefined constant is unnecessary for the convergence of the MPPT method, thus simplifying the design of the PV system. A tuning method of initial step sizes is also presented, which is derived from the approximate linear relationship between the open-circuit voltage and MPP voltage. Compared with the conventional INC method, the proposed method can achieve faster dynamic response and better steady state performance simultaneously under the conditions of extreme irradiance changes. A Matlab/Simulink model and a 5 kW PV system prototype controlled by a digital signal controller (TMS320F28035) were established. Simulations and experimental results further validate the effectiveness of the proposed method.

Adaptive Dead-Time Compensation for Grid-Connected PWM Inverters of Single-Stage PV Systems

This study presents a new software-based plug-in dead-time compensator for grid-connected pulsewidth modulated voltage-source inverters of single-stage photovoltaic (PV) systems using predictive current controllers (PCCs) to regulate phase currents. First, a nonlinear dead-time disturbance model is reviewed, which is then used for the generation of a feed-forward compensation signal that eliminates the current distortion associated with current clamping effects around zero-current crossing points. A novel closed-loop adaptive adjustment scheme is proposed for fine tuning in real time the compensation model parameters, thereby ensuring accurate results even under the highly varying operating conditions typically found in PV systems due to insolation, temperature, and shadowing effects, among others. The algorithm implementation is straightforward and computationally efficient, and can be easily attached to an existent PCC to enhance its dead-time rejection capability without modifying its internal structure. Experimental results with a 5-kW PV system prototype are presented.

A New Maximum Power Point Tracking Control Scheme in Photovoltaic Systems for Energy Saving

Maximum power point tracking (MPPT) control could significantly increase the overall reliability and conversion efficiency of grid-connected photovoltaic (PV) systems, so it can reduce energy loss in the photoelectric conversion. In this paper, a new MPPT (Zero Average Incremental Conductance) control algorithm is proposed. This method has the advantages of traditional IncCond MPPT. Moreover, it is stable against interference and not sensitive to system models. Therefore the proposed algorithm could be available and widely used in practical MPPT systems. A 200W grid-connected PV system prototype is built in lab. Experiment results verify the effectiveness of the proposed MPPT method.