- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Highly Stretchable, High‐Mobility, Free‐Standing All‐Organic Transistors Modulated by Solid‐State Elastomer Electrolytes
摘要: Highly stretchable, high-mobility, and free-standing coplanar-type all-organic transistors based on deformable solid-state elastomer electrolytes are demonstrated using ionic thermoplastic polyurethane (i-TPU), thereby showing high reliability under mechanical stimuli as well as low-voltage operation. Unlike conventional ionic dielectrics, the i-TPU electrolyte prepared herein has remarkable characteristics, i.e., a large specific capacitance of 5.5 μF cm?2, despite the low weight ratio (20 wt%) of the ionic liquid, high transparency, and even stretchability. These i-TPU-based organic transistors exhibit a mobility as high as 7.9 cm2 V?1 s?1, high bendability (Rc, radius of curvature: 7.2 mm), and good stretchability (60% tensile strain). Moreover, they are suitable for low-voltage operation (VDS = ?1.0 V, VGS = ?2.5 V). In addition, the electrical characteristics such as mobility, on-current, and threshold voltage are maintained even in the concave and convex bending state (bending tensile strain of ≈3.4%), respectively. Finally, free-standing, fully stretchable, and semi-transparent coplanar-type all-organic transistors can be fabricated by introducing a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid layer as source/drain and gate electrodes, thus achieving low-voltage operation (VDS = ?1.5 V, VGS = ?2.5 V) and an even higher mobility of up to 17.8 cm2 V?1 s?1. Moreover, these devices withstand stretching up to 80% tensile strain.
关键词: free-standing all-organic transistors,stretchable and conformal electronics,high-mobility,elastomer electrolyte,low-voltage operation
更新于2025-11-14 17:28:48
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Novel High Gain, High Efficiency DC–DC Converter Suitable for Solar PV Module Integration With Three-Phase Grid Tied Inverters
摘要: This paper proposes a novel configuration for high gain, high efficiency dc–dc converter comprising a single switch, two intermediate capacitors, and a coupled inductor for low voltage solar PV module fed applications. The high voltage gain is achieved by charging the intermediate capacitors through the coupled inductor in parallel and discharging in series. In a two winding coupled inductor, considered in the presented work, maximum two intermediate capacitors can be integrated with the secondary winding. A passive lossless clamped circuit is also provided in the converter, which recovers the leakage energy to improve the efficiency and alleviate large voltage spike. The structure of the circuit is such that the power device voltage stress is reduced thereby increasing the efficiency. The maximum power point tracking at various irradiation levels is implemented in the proposed converter. Laboratory prototype of a 300-W system with 30–45-V input and 700-V output was built to validate the theoretical claims. All the detailed analysis, simulation, and experimental waveforms are presented. A maximum converter efficiency of around 95% is achieved.
关键词: maximum power point tracking (MPPT),switched capacitor,solar PV,coupled inductor,dc micro-grid,step-up,high efficiency,3-φ inverter,low voltage,high gain,dc–dc converters
更新于2025-09-23 15:22:29
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[IEEE 2018 International Semiconductor Conference (CAS) - Sinaia (2018.10.10-2018.10.12)] 2018 International Semiconductor Conference (CAS) - Duty Cycle Adjustment for the Low Cost High Frequency Charge/Discharge CMOS Oscillator
摘要: A new technique for adjusting the duty cycle in low cost 70MHz charge/discharge based oscillator topology is proposed. Added circuitry is optimized in order to maintain the frequency variation of the initial oscillator topology (without duty cycle adjustment) for a supply voltage range between 1.6V and 2V. The circuit uses different bias currents for each stage and it is implemented using Cadence design suite. It features reduces sensitivity to supply voltage range of the output frequency and low duty cycle variation.
关键词: low voltage,duty cycle,charge/discharge oscillator,bias
更新于2025-09-23 15:22:29
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Short-term Voltage Stability Enhancement in Residential Grid with High Penetration of Rooftop PV units
摘要: Short-term voltage instability (STVI) imposes a severe threat to modern distribution networks (DNs) where a large number of intermittent distributed generator (DG) units, like rooftop photovoltaic (PV), is being integrated. Consequently, most of the international standards have been revised by incorporating the requirement of dynamic voltage support (DVS) through DG units, which is a promising approach to alleviate the STVI. In this paper, a novel DVS strategy is proposed to improve the short-term voltage stability (STVS) in residential grids. In comparison with other DVS strategies, the proposed DVS scheme maximizes the active power support from PV units following a contingency utilizing maximum allowable current of the PV inverters. Moreover, the inverter design margin is taken into account in designing the proposed scheme to limit the injected grid current within maximum allowable inverter current. The impact of inverter design margin on the STVS is explained, and the effectiveness of the proposed strategy compared with conventional DVS is demonstrated. The feasibility of the DVS control strategies in practical application is studied. Several case studies are carried out on benchmark IEEE 4 bus and IEEE 13 node test feeder systems, and finally on a ring-type DN. The results show that the proposed DVS scheme is feasible, and achieved superior performance compared to the other strategies. Furthermore, it has been shown that implementation of the proposed DVS scheme can avoid the installation of an expensive 1200 kVA D-STATCOM for STVS improvement in the target system.
关键词: Distributed generators,fault induced delayed voltage recovery,low voltage ride-through,dynamic voltage support,short-term voltage stability,distribution system
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Optimization Methods for Evaluating PV Hosting Capacity of Distribution Circuits
摘要: We propose a new transmitter architecture for ultra-low power radios in which the most energy-hungry RF circuits operate at a supply just above a threshold voltage of CMOS transistors. An all-digital PLL employs a digitally controlled oscillator with switching current sources to reduce supply voltage and power without sacrificing its startup margin. It also reduces 1/f noise and supply pushing, thus allowing the ADPLL, after settling, to reduce its sampling rate or shut it off entirely during a direct DCO data modulation. The switching power amplifier integrates its matching network while operating in class-E/F2 to maximally enhance its efficiency at low voltage. The transmitter is realized in 28 nm digital CMOS and satisfies all metal density and other manufacturing rules. It consumes 3.6 mW/5.5 mW while delivering 0 dBm/3 dBm RF power in Bluetooth Low-Energy mode.
关键词: Bluetooth Low-Energy,low-voltage oscillator,class-E/F2 power amplifier,All-digital PLL,low-power switching current-source transmitter,Internet of Things (IoT)
更新于2025-09-23 15:21:01
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[IEEE 2020 IEEE International Conference on Power Electronics, Smart Grid and Renewable Energy (PESGRE) - Cochin, India (2020.1.2-2020.1.4)] 2020 IEEE International Conference on Power Electronics, Smart Grid and Renewable Energy (PESGRE2020) - Analysis of Low Voltage Ride Through Techniques for Grid-Connected Photovoltaic Systems
摘要: This paper presents a comparative analysis of different low voltage ride though strategies proposed for operation of a grid connected two stage photovoltaic system under low voltages. The existing grid codes mandate that, under the presence of low voltages, a distributed energy resource (DER) must stay connected to the grid for a minimum amount of time. This results in abnormally high currents though the inverter of a PV system, which can potentially damage the semiconductor switches. To avoid this, low voltage ride through techniques are proposed in the literature to ensure that the DER stays connected to the grid. Traditionally, the performance of LVRT techniques is evaluated by assuming an ideal voltage dip at the point of common coupling. In this work, comparative evaluation of different LVRT techniques is carried out on the CERTS testbed with an objective to highlight the impact of network transients on their performance.
关键词: active power,reactive power,inverter.,Low voltage ride through,DC-link voltage
更新于2025-09-23 15:21:01
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[IEEE 2018 IEEE PES/IAS PowerAfrica - Cape Town, South Africa (2018.6.28-2018.6.29)] 2018 IEEE PES/IAS PowerAfrica - A Review of Grid Tied PV Generation on LV Distribution Networks
摘要: Renewable generation, at the customer side of the meter, continue to gain interest worldwide. Distribution network (DN) performance analysis, under distributed photovoltaic generation (DPVG), is paramount important to ensure DN security and reliability. This paper presents a broad review of issues, with an emphasis on grid voltage, associated with DSPVG, and proposed solutions. There has not been a comprehensive literature review of DSPVG, particularly in South Africa (SA). There is a need to quantify impacts and expectations of DSPVG connection on three phase radial low voltage (LV) DNs. In this paper, circuit diagrams and mathematical expressions for voltage rise and drop analyses, are detailed, with a comprehensive range of proposed and commercially available mitigation solutions. These include; active power curtailment (APC), reactive power control (RPC) and droop-based voltage control. APC is more ef?cient and effective for LV DNs. Sophisticated strategies combining different standalone control methods, were proposed in literature, for increase of DSPVG penetration, both locally, in residential home, and globally.
关键词: Distribution network,low voltage,voltage control,photovoltaic
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE International Conference on Smart Instrumentation, Measurement and Application (ICSIMA) - Kuala Lumpur, Malaysia (2019.8.27-2019.8.29)] 2019 IEEE International Conference on Smart Instrumentation, Measurement and Application (ICSIMA) - Power Electronic Interface for Low Voltage DC Link Using Photovoltaic Cells with ANN based MPPT
摘要: The aim of this paper is to design and develop low voltage direct current system within building structures to cater to low power load demands like LED lights, BLDC fans, desktops computers etc. The intended system comprises of a solar panel, a buck converter, a battery and a boost converter. The output of boost converter will be 48 V direct current which can cater to loads below 1 kw. The buck converter regulates the output of solar panel to constant voltage, which is stored in a battery and boosted to 48 V direct current as per household requirements. The proposed system will simplify the transmission and distribution of energy by ensuring direct current supply to appliances which are devised to run on the same. This will rule out the need for rectifier within household appliances, thereby reducing their size and cost. The future scope of this project lies in the fact that the entire system can be integrated into a module which can be used in inaccessible and rural areas by dint of a solar panel that will serve as source and the output of module will be 48V which can be directly used for household purposes. The concept of artificial neural network is incorporated for maximum power point tracking, maintaining constant output voltage.
关键词: MPPT,Low Voltage DC,ANN
更新于2025-09-23 15:21:01
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[IEEE 2020 11th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC) - Tehran, Iran (2020.2.4-2020.2.6)] 2020 11th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC) - A New Non-isolated High Gain DC-DC Converter for Grid-Connected Photovoltaic Systems
摘要: a non-coupled high gain DC-DC converter is introduced in this article. It is based on ?uk converter, also consists of two inductors, which are charged in parallel by input source and discharged in series. The voltage gain of the proposed converter is improved, while it has no transformers and coupled inductors. Furthermore, the voltage stress across the switches is decreased. Hence, switches with lower voltage level can be used in the proposed converter. Fortunately, these switches have low ON-state resistance ((cid:1792)(cid:1804)(cid:1819).(cid:1815)(cid:1814) ), which causes decreasing in switch conduction losses. Furthermore, the proposed converter has high efficiency as well as simple control system. Finally, the principle operation and simulation results are presented.
关键词: high step-up gain,high efficiency,?uk-based converter,low voltage stress,non-isolated inductor
更新于2025-09-23 15:21:01
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Low-Power-Operating 3C-SiC Ultraviolet Photodetector fora?£Elevated Temperature Applications
摘要: This work demonstrates the systematic investigation of the effects of high temperature on key performance parameters including speed, sensitivity, stability, and repeatability of a 3C-SiC/Si ultraviolet (UV) photodetector (PD) at various operating temperatures ranging from 50°C to 200°C. The device with very low dark current (≈ 0.08 pA) exhibited high sensitivity of 4466 and fast rise and decay times of 0.34 s and 0.30 s at 50°C to exposure of 254 nm UV light at a bias voltage of 20 V. Additionally, the device showed very good performance at a low operating voltage of 0.5 V and high temperature of 200°C, with a rise time of 2.68 s and decay time of 1.44 s, while maintaining good stability and repeatability. The slight decrease in performance (sensitivity from 4466 to 932) at 200°C was attributed to the increase in lattice scattering at elevated temperatures, leading to a decrease in carrier mobility. Moreover, the device was fabricated using a very cost-effective process flow. Consequently, this study can contribute to the development of low-power, fast, highly sensitive, and cost-effective 3C-SiC UVPDs for use in high-temperature photonic applications.
关键词: fast response,high sensitivity,High-temperature UVPD,low-voltage operation,3C-SiC
更新于2025-09-23 15:21:01