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oe1(光电查) - 科学论文

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?? 中文(中国)
  • [IEEE 2018 2nd International Conference on Trends in Electronics and Informatics (ICOEI) - Tirunelveli, India (2018.5.11-2018.5.12)] 2018 2nd International Conference on Trends in Electronics and Informatics (ICOEI) - Highly Efficient Constant Power Generation Using Solar Tree

    摘要: In the solar system which is connected to the grid; it is essential to select reliable and efficient solar converter and inverter with higher efficiency. The electrical converter ought to management the injecting power to the inverter and the inverter ought to be in the position to control the injecting power to the grid. This paper discusses an efficient concept of solar power generation called as Solar Tree and also the ZVT-ZCT-PWM boost converter topology and HERIC inverter topology for highly efficient system. Also we have done a simulation for this system which has desirable results.

    关键词: Solar Tree,PV system,ZVT-ZCT-PWM boost converter,HERIC inverter

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE Power & Energy Society General Meeting (PESGM) - Portland, OR, USA (2018.8.5-2018.8.10)] 2018 IEEE Power & Energy Society General Meeting (PESGM) - Experimental Determination of PV Inverter Response to Grid Phase Shift Events

    摘要: With the continued growth of renewable energy resources which interface to the electric grid via inverters, the understanding of such devices becomes ever more important to the safe and reliable operation of the bulk power system. This work investigates the specific response of a utility-scale PV inverter to grid voltage phase shift-type disturbances which sometimes occur during grid fault events. The role of the PV inverter’s phase-locked-loop (PLL) is identified as important to modeling the response. Switching-level simulations of a utility-scale PV inverter with a modeled PLL show a characteristic response when phase shift disturbances require the PLL to track what appear as fast frequency changes. Additionally, in this work a full-scale laboratory testing was carried out using the Opal real time (RT) OP5142 real time simulator and a large grid simulator to create phase shift disturbances with a high degree of repeatability. A photovoltaic (PV) inverter was connected to a grid simulator, and phase shifts were instantaneously implemented on the simulated grid, the results of the currents were then obtained. The experimental results obtained were validated with simulation results obtained from MATLAB/Simulink.

    关键词: frequency response,photovoltaics,phase-locked loops,harmonics,inverter,DER

    更新于2025-09-23 15:23:52

  • An Improved Proposed Single Phase Transformerless Inverter with Leakage Current Elimination and Reactive Power Capability for PV Systems Application

    摘要: Single-phase transformerless inverters are broadly studied in literature for residential-scale PV applications due to their great advantages in reducing system weight, cost and elevating system efficiency. The design of transformerless inverters is based on the galvanic isolation method to eliminate the generation of leakage current. Unfortunately, the use of the galvanic isolation method alone cannot achieve constant common mode voltage (CMV). Therefore, a complete elimination of leakage current cannot be achieved. In addition, modulation techniques of single-phase transformerless inverters are designed for the application of the unity power factor. Indeed, next-generation PV systems are required to support reactive power to enable connectivity to the utility grid. In this paper, a proposed single-phase transformerless inverter is modified with the clamping method to achieve constant CMV during all inverter operating modes. Furthermore, the modulation technique is modified by creating a new current path in the negative power region. As a result, a bidirectional current path is created in the negative power region to achieve reactive power generation. The simulation results show that the CMV is completely clamped at half the DC link voltage and the leakage current is almost completely eliminated. Furthermore, a reactive power generation is achieved with the modified modulation techniques. Additionally, the total harmonic distortion (THD) of the grid current with the conventional and a modified modulation technique is analyzed. The efficiency of the system is enhanced by using wide-bandgap (WBG) switching devices such as SiC MOSFET. It is observed that the efficiency of the system decreased with reactive power generation due to the bidirectional current path, which leads to increasing conduction losses.

    关键词: leakage current,transformerless inverter,reactive power,wide-bandgap (WBG),silicon carbide (SiC),photovoltaic (PV) power system

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE PES/IAS PowerAfrica - Cape Town (2018.6.28-2018.6.29)] 2018 IEEE PES/IAS PowerAfrica - Estimation of Inverter-Based Solar PV Penetration on Medium Voltage Networks Using Grid Impedance

    摘要: Installation and control of connecting inverter-based generation to medium voltage networks are constrained by network grid structure and by technical regulations that limits its penetration into the network. Medium voltage networks form the backbone to which low-voltage inverter-based generation such as solar PV systems are connect to. However, these networks generally have inconsistent impedances that vary with line lengths, conductor types and load distribution and therefore make them not as flexible and cost effective to efficiently allow adequate penetration of solar PV type distributed generation (capacity in kW) to be integrated. A generic model that mimics a medium voltage network is analyzed in this paper to determine how inverter-based generation can be maximized on the network in terms of its location by focusing on line impedance ratios to achieve voltage regulation.

    关键词: voltage regulation,Inverter-based generation,line impedance ratio,conductor type,medium voltage,line lengths

    更新于2025-09-23 15:23:52

  • Modulating Electrical Performances of In <sub/>2</sub> O <sub/>3</sub> Nanofiber Channel Thin Film Transistors via Sr Doping

    摘要: Although In2O3 nanofibers (NFs) are considered as one of the fundamental building blocks for future electronics, the further development of these NFs devices is still seriously hindered by the large leakage current, low on/off current ratio (Ion/Ioff), and large negative threshold voltage (VTH) due to the excess carriers existed in the NFs. A simple one-step electrospinning process is employed here to effectively control the carrier concentration of In2O3 NFs by selectively doping strontium (Sr) element to improve their electrical device performance. The optimal devices (3.6 mol% Sr doping concentration) can yield the high field-effect mobility (μfe ≈ 3.67 cm2 V?1 s?1), superior Ion/Ioff ratio (≈108), and operation in the energy-efficient enhancement-mode. High-κ Al2O3 thin films can also be employed as the gate dielectric to give the gate voltage greatly reduced by 10× (from 40 to 4 V) and the μfe substantially increased by 4.8× (to 17.2 cm2 V?1 s?1). The electrospun E-mode Sr-In2O3 NF field-effect transistors (NFFETs) can as well be integrated into full swing of inverters with excellent performances, further elucidating the significant advance of this electrospinning technique toward practical applications for future low-cost, energy-efficient, large-scale, and high-performance electronics.

    关键词: enhancement mode,Sr element,high performance,In2O3 nanofiber,inverter

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Portland, OR, USA (2018.9.23-2018.9.27)] 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - High-Efficiency Weight-Optimized Fault-Tolerant Modular Multi-Cell Three-Phase GaN Inverter for Next Generation Aerospace Applications

    摘要: The aircraft industry demands a significant increase in terms of efficiency and gravimetric power density of power converters for next generation aerospace applications. Between the two minimum targets, i.e. an efficiency > 98 % and a gravimetric power density > 10 kW/kg, the specification concerning the converter weight is the most challenging to fulfill. Since cooling systems and magnetic components dominate the weight breakdown of conventional converter concepts, multi-cell topologies, enabling improved semiconductors performance and reduced filtering requirements, are foreseen as promising solutions for the power electronics on board of More Electric Aircraft. On the other hand, the necessary simultaneous operation of a high number of cells inevitably limits the reliability of multi-cell converters if redundancy is not provided. In this paper, a favorable scaling trend of power density with respect to reliability, aiming to guarantee fault-tolerant operation without affecting the performance figures, is identified in modular multi-cell converters. Thus, a 45 kW weight-optimized modular multi-cell three-phase inverter featuring a redundant power stage is optimized, achieving an efficiency of 99 % and a gravimetric power density of 22.8 kW/kg.

    关键词: Multi-Objective Optimization,Figure of Merit of Power Semiconductors,Power Converters Reliability,Modular Multi-Cell Inverter,More Electric Aircraft

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Portland, OR, USA (2018.9.23-2018.9.27)] 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Current-Fed Quasi Z-Source Inverter Based PV Distributed Generation Controller

    摘要: Recently, the renewable photovoltaic distributed generation (PV-DG) enjoys a rapid growth globally due to the advancement in solar systems and power electronics technologies. However, the intermittent nature of solar radiation and performance of the attached power converters, inevitably poses some challenges to the power grids integrated large-scale solar-farms (SF). These challenges include frequency oscillations, voltage variation and power quality issues. To overcome these problems, this study proposes a Current-Fed quasi Z-source Inverter (CF-qZSI) as an alternative converter for distribution generation controllers to facilitate the integration of a PV energy source into a weak power system. The detailed model of the CF-qZSI-based distribution controller (CqZDC) and its control system are developed. The dynamic performance of the CqZDC device is evaluated to validate different objectives using an actual field data and RTDS simulation platform.

    关键词: frequency stability,current source inverter,wide band gap devices,Accommodation of renewable energy resources,power quality improving,facilitating of distributed electricity generations

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Portland, OR, USA (2018.9.23-2018.9.27)] 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Comparative Analysis of Non-Isolated and Isolated Type Partial-Power Optimizers for PV-Battery Series Inverter Architecture

    摘要: A seamless battery integration with higher power conversion efficiency and lower system power rating can be achieved by adopting the DC-series battery integration topology into a photovoltaic (PV) string inverter system, the PV-battery series inverter. The PV-battery series inverter uses the partial-power processing technique to achieve flexible current control between PV string and battery. In the process of designing the partial-power DC-DC optimizer, different types of DC-DC converters and different size of batteries can be considered, and the system efficiency and the power rating vary based on the system design. This paper presents a comparative analysis of the different type partial-power optimizers for the PV-battery series inverter in residential rooftop applications (< 10kW PV output power, < 500V DC-bus voltage), in consideration of the DC-DC converter topology. Non-isolated and isolated bidirectional DC-DC converters are considered and selection of battery voltage in each case is made to have the optimized system design. The operation of the designed DC-DC optimizer is verified through controller hardware-in-the-loop test.

    关键词: pv-battery series inverter,residential rooftop PV application,comparative analysis,non-isolated and isolated bidirectional dc-dc converters,partial-power dc-dc optimizer,PV-battery integration,dc-series

    更新于2025-09-23 15:23:52

  • [IEEE 2018 International Conference on Control, Power, Communication and Computing Technologies (ICCPCCT) - Kannur,Kerala, India (2018.3.23-2018.3.24)] 2018 International Conference on Control, Power, Communication and Computing Technologies (ICCPCCT) - Four Switch Three-Phase Inverter Fed Induction Motor for Economical and Efficient Stand Alone Solar Water Pump

    摘要: Induction motors are commonly used in industries due to its reduced cost and minimum maintenance. In this proposed system induction motor is used for the purpose of solar based water pumping application. As the energy consumption is increasing, the energy generated is alone is not able to supply the entire load requirement. Among the available renewable energy sources, solar energy is the leading one. The work proposes a three-phase four-switch inverter for photovoltaic (PV) water pumping or treatment systems. The use of batteries can be avoided, since the converter used in this proposed work is two inductor boost converter. By considering the economic factor and life span of the device, electro-chemical storage elements are avoided. Also an effective intelligent hill climbing algorithmis used to extract maximum power from PV cell. The use of a three- phase induction motor is a better solution to the dc motor for water pumping application.

    关键词: MPPT,photovoltaic (PV) power systems,Induction motor,three-phase four switch inverter,two-inductor boost converter

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE Power & Energy Society General Meeting (PESGM) - Portland, OR, USA (2018.8.5-2018.8.10)] 2018 IEEE Power & Energy Society General Meeting (PESGM) - Comparative Study of Active Power Curtailment Methods of PVs for Preventing Overvoltage on Distribution Feeders

    摘要: Overvoltage is one of the major issues on distribution grids with high penetration of photovoltaic (PV) generation. Overvoltage could be prevented through the control of active/reactive power of PVs. However, given the high R/X ratio of low voltage feeders, voltage control by using reactive power would not be as effective as using active power. Therefore, active power curtailment (APC) of PVs, though not desirable, becomes necessary at times to prevent the overvoltage issues. Existing literature is rich in centralized and droop-based methods for APC and/or reactive power control of PVs to prevent overvoltage issues. In this context, this paper revisits the most popular existing methods, and evaluates the performance of droop-based and centralized methods using a typical North American 240 V low voltage feeder with 24 residential homes. In this work, our key findings are: a) droop-based methods provided conservative solutions or did not eliminate the overvoltages completely, b) power flow sensitivity based droop approach led to 13% more curtailment than the centralized approaches, c) centralized approach had 40% less energy curtailed compared with standard droop while no overvoltages were observed, and d) operating PVs at non-unity power factor in centralized approach led to 5% less energy curtailment.

    关键词: Inverter,Overvoltage,Photovoltaic,Power Curtailment,Voltage Control,Distribution Grid

    更新于2025-09-23 15:23:52