- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Polarization-independent Tunable Optical Filter with Variable Bandwidth Based on Silicon-on-insulator Waveguides
摘要： User-centric network (UCN), which organizes a dynamic transmission point group (TPG) for each user, is regarded as a promising candidate to meet the exponential growth of mobile data traffic for 5G system. However, the severe interference under dense TP deployment in UCN from co-channel neighbor cell worsens the user performance. In this paper, to combat the fluctuation of user rate, a user-centric power control strategy is proposed, where TPs will take power control coefficient β to effectively mitigate the strong interference for each user within TPG of radius coefficient μ. Based on the strategy, semi-closed expressions of network downlink performance metric are first derived, including coverage probability and average achievable rate to the typical user, and average spectral efficiency of TP with the consideration of the impact of TPG overlapping on the signal link. The TPs and the users are modeled as independent 2-D Poisson point processes. The theoretical analysis confirms that the optimization of β and μ, which determine the area and intensity for power control, respectively, can realize the tradeoff between interference mitigation and resource utilization. Numerical results demonstrate significant performance gains of the user-centric power control strategy in coverage probability, average achievable user rate, and TP spectral efficiency, which can be improved at most by 30%, 15%, and 42%, respectively. In addition, the analysis gives the optimal values of β and μ according to the distance between TP and user.
关键词： power control,Poisson point processes,interference mitigation,User-centric network
更新于2025-09-23 15:19:57
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[IEEE 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Xiamen, China (2019.12.17-2019.12.20)] 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Digital-coded Unit Cell for Dual-band and Dual-polarized Programmable Metasurface
摘要： This paper investigates a multi-pair two-way massive MIMO amplify-and-forward full-duplex relay (FDR) system over Ricean fading channels, where multiple pairs of full-duplex users exchange information within pair through a full-duplex relay with a very large number of antennas (M for transmission and M for reception). First, the zero-forcing reception/zero-forcing transmission and maximum-ratio combining/maximum-ratio transmission processing matrices with imperfect channel state information at the relay are presented. Then, the corresponding asymptotic expressions (in M ) of the end-to-end signal-to-interference-plus-noise ratio are derived. Finally, the asymptotic spectral ef?ciency (SE) and energy ef?ciency (EE) at the general power scaling schemes when the number of the relay antennas tends to in?nity is analyzed. Theoretical analyses and simulation results show that, when M → ∞, the effects of channel estimation error, the self-loop of each user as well as the relay, inter-user interferences, the noise at users and the relay can be eliminated, respectively, if the power scaling scheme is properly selected. Besides, the considered multi-pair two-way FDR outperforms the multi-pair two-way half-duplex relaying on SE and EE performances when M is large. Moreover, a low complexity power control scheme is proposed to optimize the SE and we analyze the impact of the number of user pairs on the SE.
关键词： power control,imperfect CSI,Ricean fading channels,full-duplex,Massive MIMO
更新于2025-09-23 15:19:57
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3-Phase grid-connected building integrated photovoltaic system with reactive power control capability
摘要： Recently, a tendency in the growing of grid-connected building integrated photovoltaic (BIPV) systems has been noticed in most countries. Hence, high penetration of PV power into the system network can be observed in many points in the network. This may cause severe problems on the distribution network due to the intermittent nature of PV systems. As a feasible solution, the reactive power capability of voltage source inverter in PV systems can be employed rather than approaching expensive grid infrastructures in the distribution network. The purpose of this study is to implement a 3-phase grid-connected (BIPV) system with reactive power control to regulate the system voltage and improve the system power factor. Subsequent to this, a specific system model has been designed and developed in MATLAB Simulink application. The selection of PV system specifications is based on practical system implementation. The inverter control system along with the reactive power control has been developed for the proper system operation at different system conditions to reduce the var compensation on the utility grid. Better system accuracy of the developed system model has been found by validating with real system data. The overall system performance has indicated that the effective utilization of reactive power control of a grid-connected PV system yields to a stable, reliable and cost-effective system network operation which reduces the heavy burden on the utility grid to control the PV system effects.
关键词： Reactive power control,Voltage source inverter,Grid-connected PV system,Voltage regulation
更新于2025-09-23 15:19:57
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A Procedure for Mitigating the Light Flicker in Office LED Lighting Caused by Voltage Fluctuations
摘要： Progress in the development of LED technologies has reached a state which justifies the replacement of lighting with traditional light sources, not only in new buildings but also in existing, older ones. One of such replacements was used as an example of a lighting flicker study presented in this paper. The results of initial measurements indicated that Rapid Voltage Changes (RVCs) are the cause of light flicker. The procedure was introduced and described in this paper to provide the necessary actions to mitigate the light flicker in LED lighting. In order to fulfil this task, the source of locally induced voltage fluctuations has to be identified. A method of identification was developed and a multi-function office printer was identified as the source of RVCs. Using a less sensitive LED driver, changing the connection point of the interfering device, and improving the electrical installation were considered as a set of possible solutions. Laboratory measurements have shown significant sensitivity of the LED driver to RVCs. The identified source of voltage disturbances was confirmed by a simulation of supply voltage variation in the presence of such device in Matlab Simulink with the use of digital flickermeter.
关键词： voltage fluctuations,light flicker,sensitivity of LED drivers,digital flickermeter,power control with zero voltage crossing
更新于2025-09-23 15:19:57
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[IEEE 2018 International Conference on Smart Grid and Clean Energy Technologies (ICSGCE) - Sg. Long, Cheras, Kajang, Malaysia (2018.5.29-2018.6.1)] 2018 International Conference on Smart Grid and Clean Energy Technologies (ICSGCE) - A Novel Five-Level Inverter Topology with Reactive Power Control for Grid-Connected PV System
摘要： These days multilevel inverters are more popular for grid-connected photovoltaic (PV) systems due to their low cost and high efficiency, as they effectively reduce total harmonic distortion (THD) and electromagnetic interference which results leakage current. Traditional multi-level inverters can only inject real power that cannot provide quality output power. A new international standard VDE-AR-N4105 states that for a grid tied inverter of power rating below 3.68kVA, a power factor (PF) of 0.95 leading to 0.95 lagging should be achieved. So, in this paper the proposed five-level inverter topology for grid-tie PV is controlled using a reactive power control method that ensures higher efficiency while enhancing the stability of the system. The proposed closed loop reactive power control technique additionally provides the ability to inject reactive power into the system. In this proposed topology the reactive power flow standard of operation is explained in details in relation to the proposed multi-level inverter topology. To validate the accuracy of the theoretical analysis, the control technique was applied to the existing multi-level inverter topology and then has been simulated in MATLAB/Simulink software. Comparisons were done on the basis of using and not using PLL for the existing multilevel topology and it is found that, synchronization is achieved with current and voltage if PLL is used, as a result PF is maintained close to unity whereas without PLL the PF decreases. Moreover the five-level output provides a much better output and better PF then other existing topologies.
关键词： phase-locked loop (PLL),multi-level inverters,solar PV,reactive power control
更新于2025-09-23 15:19:57
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Secondary-side-only Phase-shifting Voltage Stabilization Control with a Single Converter for WPT Systems with Constant Power Load
摘要： In recent years, wireless power transfer technology has received considerable attention because of its wide range of applications. Most of the literature focuses on the resistance load or constant voltage load, and the constant power load is almost never considered. The open loop transfer function of a constant power load is unstable, and therefore closed loop stabilization is required. Furthermore, communication between the two sides is often used but it may not be available. In order to stabilize the load voltage without resorting to coordination with the primary side and discontinuous operation causing big voltage transients, this paper proposes a control strategy for only the secondary side using a single converter. It is based on the combination of synchronous rectification and symmetric phase shift, without communication with the primary side. While the primary side is not manipulated, the AC/DC converter regulates the amplitude of the secondary coil voltage and stabilizes the constant power load voltage on the DC side via a simple PI control. In this paper, the control concept, design and stability analysis are provided. The proposed control is verified through experimental results in both static and dynamic scenarios, achieving a controller that is simple to design and has smooth waveforms.
关键词： secondary side,wireless power transfer,phase shifting,constant power load,power control
更新于2025-09-19 17:15:36
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Auto-Tuning PID Distributed Power Control for Next-Generation Passive Optical Networks
摘要： This work proposes an adaptive auto-tuning distributed power control strategy aided by proportional-integral-derivative (PID) and by Adaline artificial neural network (AANN) approaches. The power control mechanism is realized for the upstream of next-generation passive optical networks (NG-PON), primarily deployed in the context of optical code division multiplexing access passive networks. The primary results demonstrate the ability of control and adaptive auto-tuning of the proposed AANN-based DPCA, considering realistic error estimates in the optical channel. For the sake of comparison, an adaptive auto-tuning procedure through the Tyreus–Lyuben method is included, indicating superior Euclidean norm of the NMSE performance combined with the lower complexity of the proposed NN-based DPCA method.
关键词： Tyreus-Lyuben (TL),Adaptive auto-tuning,Distributed power control algorithm (DPCA),Proportional-integral-derivative (PID),Adaline Neural Network (AANN),Next-generation passive optical networks (NG-PONs)
更新于2025-09-19 17:15:36
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Direct Synthesis and Design of Dispersive Waveguide Bandpass Filters
摘要： Wireless power transfer (WPT) is an emerging technology with an increasing number of potential applications to transfer power from a transmitter to a mobile receiver over a relatively large air gap. However, its widespread application is hampered due to the relatively low efficiency of current Wireless power transfer (WPT) systems. This study presents a concept to maximize the efficiency as well as to increase the amount of extractable power of a WPT system operating in nonresonant operation. The proposed method is based on actively modifying the equivalent secondary-side load impedance by controlling the phase-shift of the active rectifier and its output voltage level. The presented hardware prototype represents a complete wireless charging system, including a dc–dc converter which is used to charge a battery at the output of the system. Experimental results are shown for the proposed concept in comparison to a conventional synchronous rectification approach. The presented optimization method clearly outperforms state-of-the-art solutions in terms of efficiency and extractable power.
关键词： wireless charging,inductive power transmission,Dc-dc power converters,reactive power control,phase-shift control,rectifiers,impedance matching
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 2nd British and Irish Conference on Optics and Photonics (BICOP) - London, United Kingdom (2019.12.11-2019.12.13)] 2019 IEEE 2nd British and Irish Conference on Optics and Photonics (BICOP) - Temperature Stability of Elastomeric Colloidal Quantum Dot Colour Converter
摘要： Underwater wireless optical communications are an emerging solution to the expanding demand for broadband links in oceans and seas. In this paper, a cellular underwater wireless optical code division multiple-access network is proposed to provide broadband links for commercial and military applications. The optical orthogonal codes are employed as signature codes of underwater mobile users. Fundamental key aspects of the network, such as its backhaul architecture, its potential applications, and its design challenges, are presented. In particular, a promising underwater localization and positioning scheme based on this cellular network is presented. Furthermore, the proposed network is used as infrastructure of centralized, decentralized and relay-assisted underwater sensor networks for high-speed real-time monitoring. Finally, probable design challenges, such as cell edge coverage, blockage avoidance, power control, and network capacity, are addressed.
关键词： power control,optical CDMA networks,undersea localization and positioning,underwater sensor networks,Underwater wireless optical communications,relay-assisted transmission
更新于2025-09-19 17:13:59
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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) - A new approach for Multi junction solar cells from off the shelf individual cells: GaAs/Si
摘要： Interference is one of the major obstacles to improving the performance in wireless communication systems. As the ever-growing data traffic is carried over extremely dense networks, how to deal with interference becomes even more relevant. In this paper, we investigate a network with N pairs of users transmitting on the same channel simultaneously from the energy efficiency (EE) perspective. For such an interference network, we aim to address two issues: what is the EE tradeoff between users and how to design energy-efficient resource allocation scheme? To answer these two questions, we formulate a non-concave multi-objective optimization problem (MOOP) to investigate the EE tradeoff, taking into account the minimum data rate requirement of each user. The weighted Tchebycheff method is utilized to solve the MOOP by converting it into a single-objective optimization problem, which is then solved by the Dinkelbach method and the concave-convex procedure method. Based on the above, a power control algorithm is developed for the interference network to achieve at least a local optimum. The proposed algorithm is compared with the orthogonal bandwidth sharing, where each user orthogonally shares the whole bandwidth without interfering each other. In this scenario, the weighted Tchebycheff and the Dinkelbach methods are also utilized to develop the optimal bandwidth allocation and power control algorithm. The performance of the proposed algorithms is verified by numerical results, which show that it is better to share the bandwidth orthogonally rather than non-orthogonally if the interference between each user pair is stronger than a given threshold.
关键词： multi-objective optimization,energy efficiency,Interference channel,bandwidth allocation and power control
更新于2025-09-19 17:13:59