- 标题
- 摘要
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- 实验方案
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An analog-to-digital converter and intelligent controller for use in a DAQ system processing PMT signals from very high energy astrophysics experiments
摘要： Modern instrumentation for very high energy gamma-ray astronomy and astrophysics requires efficient and precise digitisation of PMT signals from Cherenkov light generated by incoming cosmic ray particles over the energy range from hundreds of GeV up to several hundred TeV. This dynamic range of more than 1000 is coupled with a requirement for very low noise operation. We have developed modern multi-channel analog-to-digital converters (model BPA-8) together with a data acquisition system managed with an intelligent crate-controller (model K-167) which controls the measurement modules. The electronics described in this paper is accepted to be used to record PMT signals with high precision and efficiency, allowing reliable extraction and precise analysis of Cherenkov signals from high energy gamma-rays emitted by astrophysical objects.
关键词： intelligent crate-controller,astroparticle detectors,analog-to-digital converter
更新于2025-09-23 15:23:52
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Performance Analysis of Maximum Power Point Tracking Algorithms Under Varying Irradiation
摘要： Photovoltaic (PV) system is one of the reliable alternative sources of energy and its contribution in energy sector is growing rapidly. The performance of PV system depends upon the solar insolation, which will be varying throughout the day, season and year. The biggest challenge is to obtain the maximum power from PV array at varying insolation levels. The maximum power point tracking (MPPT) controller, in association with tracking algorithm will act as a principal element in driving the PV system at maximum power point (MPP). In this paper, the simulation model has been developed and the results were compared for perturb and observe, incremental conductance, extremum seeking control and fuzzy logic controller based MPPT algorithms at different irradiation levels on a 10.2 kW PV array. The results obtained were analysed in terms of convergence rate and their efficiency to track the MPP.
关键词： perturb and observe,fuzzy logic controller,scalar gradient extremum seeking control,Photovoltaic system,incremental conductance,MPPT algorithms
更新于2025-09-23 15:23:52
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[IEEE 2018 15th International Conference on Control, Automation, Robotics and Vision (ICARCV) - Singapore, Singapore (2018.11.18-2018.11.21)] 2018 15th International Conference on Control, Automation, Robotics and Vision (ICARCV) - Quadrotors' Low-cost Vision-based Autonomous Landing Architecture on a Moving Platform
摘要： In this paper, a low-cost vision-based autonomous landing architecture for an unmanned aerial vehicle (UAV) on a moving platform is presented. First, a novel landing pad was designed for a monocular camera to robustly detect the pad in both high and low altitudes. In order to solve mirror effect and occasional misidentification, a 3D points cluster algorithm for relative position estimation is presented. Second, the dynamics of the quadrotor is simplified for this landing task and a PD controller is designed based on the estimated relative position. Finally, the low-cost system architecture of the quadrotor and the experiment results are both presented to show the effectiveness of the proposed method.
关键词： landing pad design,PD controller,quadrotor,moving platform,low-cost,vision-based,3D points cluster algorithm,autonomous landing
更新于2025-09-23 15:23:52
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An interferometric structure with a dual-resonance long period grating for strain sensing
摘要： Spectral characteristics and amplitude tunability of a long period grating with a dual-resonance inside fiber loop mirror are studied in terms of applied stress caused by elongation. Inserting the polarization controller between grating and part of polarization maintaining fiber in the loop structure enables tuning of resonance and interferometric peaks. The maximum sensitivity of demonstrated sensor is of 1.943 dB/mε for the range of 1.1–4.4 mε. Combination of these two optical components allows to measure strain in a wider range comparing with sensors based on standard long period grating.
关键词： Fiber loop mirror,Polarization controller,Polarization maintaining fiber,Strain sensor,Long period grating
更新于2025-09-23 15:23:52
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An Efficient Technique using Modified p-q Theory for Controlling Power Flow in a Single-Stage Single-Phase Grid-Connected PV System
摘要： In this paper, an efficient power conditioning unit (PCU) is presented for a single-phase grid-connected photovoltaic system (GCPVS) incorporating both maximum power-point tracking (MPPT) and current control algorithms in a single-stage. Modified p-q theory is applied to derive the reference signal for a hysteresis band current (HBC) controller so that independently the active and reactive power sharing between the photovoltaic (PV) system and the grid can be controlled. Enhanced stability during the internal dynamics, caused by the variations in PV generation and load conditions, is the prime aspect of the controller. The performance of the proposed p-q theory correlated HBC controller is evaluated against tracking of maximum PV power and compensation of load reactive power under the changeable atmospheric and load conditions, and also compared with the widely used conventional proportional resonant (PR) controller to justify superiority. Simulation and experiment are carried-out under variable weather and different load conditions to validate acceptability of the proposed control scheme.
关键词： modified p-q theory,Single-stage,hysteresis band current (HBC) controller,grid-connected photovoltaic system (GCPVS),power flow controlling
更新于2025-09-23 15:23:52
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AIP Conference Proceedings [Author(s) EMERGING TRENDS IN MATHEMATICAL SCIENCES AND ITS APPLICATIONS: Proceedings of the 3rd International Conference on Recent Advances in Mathematical Sciences and its Applications (RAMSA-2019) - Noida, India (17–19 January 2019)] - Modeling and fuzzy logic control of photovoltaic-fuel cell-battery hybrid vehicle
摘要： In this paper, modelling of hybrid photovoltaic fuel cell and battery included vehicle were done apart from designing of fuzzy logic controller for the above system. Here, photovoltaic (PV) generator and proton exchange membrane fuel cell (PEMFC) were connected in parallel that is further connected to the battery (which is used as an energy reservoir). Modelling was done using Simulink? software; and different models of PV, PEMFC and battery had been done using the defining equation available in the literature. A rule-based fuzzy logic controller was modelled in the Simulink? software. Finally, using different parameters; simulation of the complete system had been done and results were analysed.
关键词： Fuzzy Logic Controller,Hybrid Vehicle,PEMFC
更新于2025-09-23 15:23:52
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dSPACE Controller Based Enhanced Piezoelectric Energy Harvesting System Using PI-Lightning Search Algorithm
摘要： This paper presents a new lightning search algorithm (LSA) to enhance the piezoelectric energy harvesting system converter (PEHSC) using the dSPACE DS1104 controller board as the proportional-integral voltage controller (PIVC). To extract the energy from the vibration is challenging and difficult due to the uncertain behavior of vibration. Since the piezoelectric vibration transducer generates low AC voltage output with fluctuations and harmonics, it is difficult to control this low-level signal of various magnitudes. Therefore, the behavior of the converter is governed by its controller. The traditional PIVC process for improved parameter values of proportional gain (Kp) and integral gain (Ki) is commonly implemented via trial and error, which does not lead to an acceptable response in several conditions. Hence, this paper offers a method for finding the optimal Kp and Ki values for PIVC that eliminates the time-consuming conventional trial-and-error process. This method is applied to PEHSC development by producing values of Kp and Ki performed in the PIVC depending on the estimated outcomes of the objective function defined via LSA. The mean absolute error (MAE) is used as the objective function for reducing the output error of the PEHSC. The LSA optimizes the Kp and Ki values that give the minimum MAE, and the effect on the PEHSC is in terms of the rising and settling times. The development process and efficiency of the PIVC are demonstrated and examined via simulations using the MATLAB tools. The LSA-based PIVC (LSA-PI) is compared with the particle swarm optimization (PSO)-based PIVC (PSO-PI) and the backtracking search algorithm (BSA)-based PIVC (BSA-PI). The performance of the LSA-PI-based PIVC is then validated through hardware implementation using the dSPACE DS1104 control board. The simulation results are compared with the hardware results of PEHSC to validate the overall efficiency of the system. Finally, the results are regulated at an output of 7 V DC from an input range of 150 mV～250 mV AC at 30 Hz through a closed-loop using the LSA-PIVC.
关键词： PI controller,optimization,Piezoelectric energy harvesting,dSPACE controller
更新于2025-09-23 15:22:29
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[IEEE 2018 53rd International Universities Power Engineering Conference (UPEC) - Glasgow, United Kingdom (2018.9.4-2018.9.7)] 2018 53rd International Universities Power Engineering Conference (UPEC) - A PV interface system based on high-gain high-frequency link converter
摘要： this paper presents a PV interface system based on an isolated high-gain high-frequency dc/dc converter. The PV array is connected to a square pulse high-frequency H-bridge. The Pulse Width (PW) of the output square voltage from the H-bridge inverter is controlled to extract the maximum power from the PV array using any of the Maximum Power Point Tracking (MPPT) schemes. The output of the H-bridge inverter is connected to the primary winding of a multi-secondary high-frequency transformer where each secondary winding is connected to a bridge rectifier. The bridge rectifiers are connected in series to boost the output dc-link voltage which is interfaced with the grid using a Voltage Source Inverter (VSI). During normal operating conditions, the VSI is controlled to regulate the dc-link voltage to transfer the harvested maximum power from the PV array to the grid at unity power factor. Moreover, the paper presents a Low Voltage Ride Through (LVRT) controller to meet the grid-code requirements and simultaneously protecting the proposed interface system from overvoltage. Simulation results based on PSCAD/EMTDC software are provided to assess the proposed PV interface system during different modes of operations
关键词： PV interface system,High frequency link,MPPT,LVRT controller
更新于2025-09-23 15:22:29
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Impact Analysis of DSSC on Distance Relay Performance under Fault Conditions
摘要： This paper demonstrates the impact analysis of the Distributed Static Series Compensator (DSSC), on the performance of distance relay protection of high voltage transmission lines. The concept of DSSC model with its control circuit and distance relay are described. A five bus test system with DSSC and distance relay is designed with the help of MATLAB/SIMULINK software. The impact of DSSC on distance protection relay for different fault conditions and various fault locations is analyzed. The results of simulation show that the connection of DSSC in the transmission system changes the transmission line impedance greatly as estimated by the distance relay to be less or greater than the actual impedance in fault conditions. Hence, the distance relay performance changes, either over reaches or under reaches.
关键词： FACTS Controller,Distributed FACTS Devices,Distributed Static Series Compensator,High Voltage Transmission Line,Distance Relay
更新于2025-09-23 15:22:29
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Precisely Automatic Time Window Locating for an Interferometric Fiber-Optic Sensor Array Based on a TDM Scheme
摘要： Interferometric fiber-optic sensors are often organized in the form of large-scale arrays by lending the technique of time division multiplexing (TDM) to reduce the system cost. Discriminating the time windows for different sensor units is the prerequisite to successfully demodulate the sensing message, but it traditionally calls for a very time-consuming manual calibration process. To combat this problem, a novel automatic time window locating method is proposed in this paper. It introduces the concept of shape function and carries out the cross-correlation operation between the shape function and the sensor signal. The shape function is defined as the function whose curve profile reflects the main data characteristics of the sensor signal. The time window information is then extracted from the correlation result. This whole process is carried out automatically by the interrogation controller of the sensor system without any manual intervene. Experiments are conducted to validate this method. The proposed method can greatly reduce the complexity of locating time windows in large-scale TDM sensor arrays, and make the practical use of the TDM scheme much more convenient.
关键词： fiber-optic sensor,interrogation controller,time division multiplexing (TDM),time window,cross correlation
更新于2025-09-23 15:22:29