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oe1(光电查) - 科学论文

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?? 中文(中国)
  • [IEEE 2018 International Conference on Electronics, Control, Optimization and Computer Science (ICECOCS) - Kenitra, Morocco (2018.12.5-2018.12.6)] 2018 International Conference on Electronics, Control, Optimization and Computer Science (ICECOCS) - Backstepping Control for Three Phase Single Stage Grid Connected PV System with Improved Power Quality

    摘要: The development of PV-systems has increased due to the high demand for clean energy. Used worldwide in the distributed power generation markets, the photovoltaic energy must not only be maximized, but also adapted to the global standards on harmonic emissions towards the power utility. Hence, the tracking of the maximum power point and the harmonic filtering becomes necessary. A three-phase single stage grid-connected Photovoltaic system consisting of a photovoltaic array and a three-phase PWM inverter coupled through the LCL-filter to the electrical grid is studied in this paper. A new control design is developed to maximize power in the side of PV panels and to ensure a unit power factor at the grid side. Grid synchronization is provided by a three-phase PLL (Phase-Locked Loop) and the closed-loop stability is demonstrated using Lyapunov analysis. Simulation results clearly illustrate that the proposed controller has achieved all of its objectives. In order to demonstrate the performance of the LCL-filter in minimizing the harmonics produced by the photovoltaic inverter, the frequency response of the injected currents was compared to that obtained using a simple L-filter.

    关键词: backstepping controller,PV systems,maximum power point tracking,three-phase inverter,LCL-filter,unity power factor,grid connection

    更新于2025-09-23 15:22:29

  • An Improved Frequency Measurement Method from the Digital PLL Structure for Single-Phase Grid-Connected PV Applications

    摘要: The Phase Locked Loop (PLL) technique has been studied to obtain the phase and frequency information in grid-connected distributed generations for the sake of synchronizing the grid voltage and the inverter output current. In particular, the line frequency information, such as the anti-islanding function, is very important for the grid connection requirement. This paper presents a novel frequency measurement method from the digital PLL control structure for single-phase grid-connected PV applications. The conventional PLL controller uses the phase information to calculate the frequency of PV inverter output voltage after every line cycle and has shown a relatively low accuracy. This paper uses the angular frequency to directly measure the frequency after every line cycle. To verify the validity of the proposed method compared with the conventional method, a simulation was conducted. According to the simulation results, the measurement error of the proposed method is 80 times lower than the conventional one.

    关键词: phase locked loop,frequency measurement,photovoltaic generation,grid-connection,PV inverter

    更新于2025-09-23 15:21:01

  • Territorial planning for photovoltaic power plants using an outranking approach and GIS

    摘要: In 2015 the Paris Agreement set the goals for reducing greenhouse gas emissions. To achieve these objectives, it is necessary to boost electricity generation coming from renewable energy sources, particularly solar energy. Finding areas that are suitable for solar farm development is crucial for the economic feasibility of these projects and the sustainable use of land. This research investigates how to identify optimal sites for the development of solar plants. A GIS-based approach combined with a Multi-Criteria Evaluation methodology is used to create a map which shows a ranking of areas with high potential for solar farm development. The GIS-based methodology is employed in the treatment of the legal and environmental criteria and sub-criteria to delimit the suitable locations. These locations are evaluated and ranked by order using the PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluations). The importance of each criteria and sub-criteria is determined by an Analytic Hierarchy Process (AHP). In the Valencian Community the most discriminating criterion, when selecting the best locations, is the intensity of solar radiation, while temperature is the least discriminant. In terms of areas, the most suitable are located in the province of Alicante, while the least suitable are in the north of the Castellón province. It is also observed that the most appropriate locations are those that have greater solar radiation, and/or are at a lower altitude.

    关键词: AHP,MCDM,solar energy,Solar farms,grid connection,best sites,PROMETHEE,GIS

    更新于2025-09-19 17:13:59

  • Analyzing territory for the sustainable development of solar photovoltaic power using GIS databases

    摘要: Solar energy generated by grid-connected photovoltaic (GCPV) systems is considered an important alternative electric energy source because of its clean energy production system, easy installation, and low operating and maintenance costs. This has led to it becoming more popular compared with other resources. However, finding optimal sites for the construction of solar farms is a complex task with many factors to be taken into account (environmental, social, legal and political, technical-economic, etc.), which classic site selection models do not address efficiently. There are few studies on the criteria that should be used when identifying sites for solar energy installations (large grid-connected photovoltaic systems which have more than 100 kWp of installed capacity). It is therefore essential to change the way site selection processes are approached and to seek new methodologies for location analysis. A geographic information system (GIS) is a tool which can provide an effective solution to this problem. Here, we combine legal, political, and environmental criteria, which include solar radiation intensity, local physical terrain, environment, and climate, as well as location criteria such as the distance from roads and the nearest power substations. Additionally, we use GIS data (time series of solar radiation, digital elevation models (DEM), land cover, and temperature) as further input parameters. Each individual site is assessed using a unique and cohesive approach to select the most appropriate locations for solar farm development in the Valencian Community, a Spanish region in the east of Spain.

    关键词: Solar energy,Solar radiation,Grid connection,Solar farms

    更新于2025-09-11 14:15:04

  • [IEEE 2018 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC) - Kota Kinabalu, Malaysia (2018.10.7-2018.10.10)] 2018 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC) - Transformer-less Single Phase H2D4 Inverter with Voltage Controller for Grid-tied PV System

    摘要: Nowadays the transformer-less photovoltaic (PV) grid connected inverter is more popular because of its higher efficiency, compact size and lower cost. The issue of leakage current is a technical challenge, which needs to be controlled carefully. Moreover, many inverter topologies have been proposed to proficient the inverter to control the reactive power to a certain point in order to maintain the power factor (PF) close to one. In case of solar PV system, voltage fluctuation and synchronization with the utility grid is the challenging issue. Therefore, in this paper a new transformer-less inverter is proposed consisting of four diodes and two IGBT switches called H2D4 topology. The proposed topology can overcome the issue of leakage current by maintaining the common mode (CM) voltage constant while maintain low total harmonic distortion (THD) and higher PF. Because of the minimum number of IGBT switches, the leakage current and the conduction loss decrease. Besides, the size of the system is also decreased. Additionally, voltage fluctuation and synchronization are controlled by a newly proposed voltage controlled closed loop system where duty ratio is controlled. The proposed topology and the existing neutral point clamped (NPC) and H6 topologies are simulated in MATLAB/Simulink software, to clarify the theoretical analysis. It is found that the voltage controller closed loop control system of H2D4 inverter topology more efficiently control the voltage fluctuation problems while maintaining a low current THD with higher efficiency and high PF as compared with the system without control topology.

    关键词: Grid connection,voltage synchronization,utility grid,total harmonic distortion,transformer-less inverter,power factor,leakage current,reactive power

    更新于2025-09-04 15:30:14