Operation Of PV Plants Research Articles

Comparing solar inverter design rules to subhourly solar resource simulations

The input of a solar inverter depends on multiple factors: the solar resource, weather conditions, and control strategies. Traditional design calculations specify the maximum current either as 125% of the rated module current or as the maximum 3 h average current from hourly simulations over a typical year, neglecting extreme irradiance conditions: cloud enhancement events that usually last minutes. Inverter power-limiting control strategies usually prevent extreme events to cause strong currents at the inverter, but in some cases, they can fail, leading to high currents. In this study, we aim to report how frequent and strong these high currents could be. We use 10 years of 1 min data from seven stations across the United States to estimate the photovoltaic string output through modeling the short-circuit current Isc, and the maximum-power point current Imp, and compare them to traditional inverter design values. We consider different configurations: minutely to hourly resolution; 5 min to 3 h averaging time intervals; monofacial and bifacial modules (with a case of enhanced albedo); and 3 fixed-tilt angles and horizontal single-axis tracking. The bifacial modules with enhanced albedo lead to the highest currents for 1 min data, exceeding 3 h averages by 53% for Isc and 38% for Imp. The 3 h average maxima surpass the conservative 125% design rule for bifacial modules. Inverter ratings at either a 200% of the rated current or 1.55 times the 3 h maximum could withstand all events regardless of control strategies. In summary, for some locations it is prudent to compare current design rules to subhourly simulations to guarantee the fault-free operation of solar PV plants.

Towards the development of an optimized Decision Support System for the PV industry: A comprehensive statistical and economical assessment of over 35,000 O&M tickets

AbstractDue to the overall declining costs of photovoltaic systems, market players in the operation and maintenance sector are under increasing price pressure when offering their services. The automation and standardization of maintenance and failure tickets as well as their statistical and economical evaluation are key to ensure optimal yield and long lifetime. A thorough understanding of typical faults, classified through a standardized taxonomy, can be a pathway of developing location and technology specific decision support, offering cost‐time efficient solutions to reduce component downtime and costs in case of failure appearance. A useful method for this approach is the Cost Priority Number, a methodology to assess technical failures and their economic impact in energy systems. In this work, this method is further improved to be applied to individual use cases to make it useful in the actual operation of PV plants. A standardized ticket taxonomy for the operational phase of PV systems has been developed where more than 35,000 PV systems' tickets have been statistically evaluated, and a fully automated methodology to calculate the cost of individual maintenance tickets has been developed.

Modelling and Analysis of Three Phase Grid Photo Voltic System for Electric Vehicle

Abstract: Renewable energy systems area unit seemingly to become wide spread within the future thanks to adverse environmental impacts and step-up in energy prices connected with the exercise of established energy sources. Solar and grid energy resources area unit various to every different which can have the particular potential to satisfy the load quandary to a point. However, such solutions any time researched severally aren't entirely trustworthy thanks to their impact of unstable nature. During this perspective, autonomous electrical phenomenon and grid hybrid energy systems are found to be a lot of economically viable various to meet the energy demands of diverse isolated shoppers worldwide. Conservation of energy is extremely traditional these days however management of energy is extremely essential issue to figure on the idea of change to energy generation devices for continuous provide of dc storage conjointly demand of electricity is increasing day by day however accessible wattage plants aren't ready to provide electricity as per the strain wants. The main objective of the project is to supply a framework for promotion of enormous grid connected grid - solar PV hybrid system for optimum and economical utilization of transmission infrastructure and land. Project conjointly aims to encourage new technologies, ways and way-outs involving military operation of grid and solar PV plants. Battery storage could also be other to the hybrid project to cut back the variability of output power from grid solar hybrid plant, for providing higher energy output for a given capability at delivery purpose, by putting in further capability of grid and solar energy in an exceedingly grid solar hybrid plant and making certain handiness of firm power for a specific amount. Keywords: Electric vehicle, solar power, vehicle-to-grid, management of power.

Comparison of Environmental Impact Assessment Methods in the Assembly and Operation of Photovoltaic Power Plants: A Systematic Review in the Castilla—La Mancha Region

Solar energy is in high demand due to its environmental benefits and economic potential; however, concerns remain about the total impact it holds. In 2020, for Spain, Castilla-La Mancha was the second autonomous community with the highest photovoltaic energy production. Thus, a systematic review on 15 large-scale PV solar energy projects was carried out to assess the industry impacts, through environmental impact assessment (EIA), within the Autonomous Community of Castilla—La Mancha. An estimation of these impacts from a pre-operational approach is presented, based on primary energy needs and emissions discarded during its life cycle due to the manufacture, operation, and recycling of the photovoltaic modules. Based on both the life cycle assessment (LCA) and EIA, the approaches were compared with the results obtained. The obtained results suggest that determining the actual impacts of power plants in this region could provide justified information for the public administration and technicians in the measures for the installation and operation of PV plants and the future benefits of renewable solar technologies. Furthermore, the results indicate the possibility to recognize the relationship between the size of the plant and a high generation capacity, with a shorter time to pay for emissions from the manufacture and recycling of panels, suggesting that it is around 1.66–2.08 years for the Castilla-La Mancha region.

Solar PV-Wind Hybrid Energy Generation System

Renewable energy systems area unit seemingly to become wide spread within the future thanks to adverse environmental impacts and step-up in energy prices connected with the exercise of established energy sources. Solar and wind energy resources area unit various to every different which can have the particular potential to satisfy the load quandary to a point. However, such solutions any time researched severally aren't entirely trustworthy thanks to their impact of unstable nature. During this perspective, autonomous electrical phenomenon and wind hybrid energy systems are found to be a lot of economically viable various to meet the energy demands of diverse isolated shoppers worldwide. Conservation of energy is extremely traditional these days however management of energy is extremely essential issue to figure on the idea of change to energy generation devices for continuous provide of dc storage conjointly demand of electricity is increasing day by day however accessible wattage plants aren't ready to provide electricity as per the strain wants. The main objective of the project is to supply a framework for promotion of enormous grid connected wind - solar PV hybrid system for optimum and economical utilization of transmission infrastructure and land. Project conjointly aims to encourage new technologies, ways and way-outs involving military operation of wind and solar PV plants. Battery storage could also be other to the hybrid project to cut back the variability of output power from wind solar hybrid plant, for providing higher energy output for a given capability at delivery purpose, by putting in further capability of wind and solar energy in an exceedingly wind solar hybrid plant and making certain handiness of firm power for a specific amount.

Outdoor PV System Monitoring—Input Data Quality, Data Imputation and Filtering Approaches

Photovoltaic monitoring data are the primary source for studying photovoltaic plant behavior. In particular, performance loss and remaining-useful-lifetime calculations rely on trustful input data. Furthermore, a regular stream of high quality is the basis for pro-active operation and management activities which ensure a smooth operation of PV plants. The raw data under investigation are electrical measurements and usually meteorological data such as in-plane irradiance and temperature. Usually, performance analyses follow a strict pattern of checking input data quality followed by the application of appropriate filter, choosing a key performance indicator and the application of certain methodologies to receive a final result. In this context, this paper focuses on four main objectives. We present common photovoltaics monitoring data quality issues, provide visual guidelines on how to detect and evaluate these, provide new data imputation approaches, and discuss common filtering approaches. Data imputation techniques for module temperature and irradiance data are discussed and compared to classical approaches. This work is intended to be a soft introduction into PV monitoring data analysis discussing best practices and issues an analyst might face. It was seen that if a sufficient amount of training data is available, multivariate adaptive regression splines yields good results for module temperature imputation while histogram-based gradient boosting regression outperforms classical approaches for in-plane irradiance transposition. Based on tested filtering procedures, it is believed that standards should be developed including relatively low irradiance thresholds together with strict power-irradiance pair filters.

A Copula Function Based Monte Carlo Simulation Method of Multivariate Wind Speed and PV Power Spatio-Temporal Series

As high penetration of uncertain wind and solar energy into power system, spatio-temporal correlation of wind and solar energy is of great necessity for planning and operation of wind farms and PV plants. A Copula function and first order Markov process based Monte Carlo simulation method of multivariate wind speed and PV power spatio-temporal series is proposed in this paper. In the proposed approach, either spatial correlation or temporal correlation of wind speed and PV power series is considered including cross-correlation between all series and self-correlation of every series. The results of case study based on National Renewable Energy Laboratory (NREL) of the U.S. Department of Energy are analyzed, which verify the scientific and feasibility of the proposed approach.

ANALYSIS OF MONITORING DATA ON THE OPERATION OF PV-INVERTERS CONNECTED TO DISTRIBUTION NETWORK

The article deals with the problems of the PV plants operation in the low voltage network (LVN), namely the influence of PV generation on bus voltages and stability of network, as well as disconnecting the inverters from network in order to avoid overvoltages. The operating of PV inverter tied to LVN is considered on the framework of the reduced two-bus equivalent circuit. One bus of this circuit describes the inverter which is connected to the step-up transformer via short line and second one is the equivalent representation of LVN. The reduced two-bus circuit in contrast to the multi-bus schemes has exact solutions for power flows between PV plant and network. The analytical solutions obtained for this model allows us to determine the voltage stability region, the disconnecting conditions from the network (islanding), the dependence of the bus voltages on the levels of generation and load. On the base of this model, the monitoring data for power and output voltages of three-phase Growatt 30 kW inverter were analyzed. The inverter is tied to LVN by a relatively short line segment with known parameters which is typical for private and small industrial photovoltaic systems. The stable operation of PV plant in the network depends on the ratio of generation and consumption levels at the bus on the plant side, as well as on the capacity of the connecting line. Under analyzing of an overvoltage in the inverter bus appearing due to large solar radiation, one should take into account the limited inverter’s possibility to reduce the output power by changing the operating point on the curve “voltagepower”. The article performs the optimization calculations which determine the parameters characterizing the inverter and line capacity. The developed method for analyzing monitoring data of modern inverters can be a useful tool in solving problems of PV plant equipment diagnostics, as well as of predicting the electricity amount supplied to the network.