- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Low-frame-rate single camera system for 3D full-field high-frequency vibration measurements
摘要： A single-camera stereo-digital image correlation (stereo-DIC) system to obtain 3D full-field vibration measurements is proposed. The optical setup is composed of two planar mirrors and a single low frame rate camera, thus resulting in a compact and low-cost equipment. The two mirrors are used to create pseudo-stereo images of a target surface on the camera sensor, which are then correlated by using stereo-DIC. The image acquisition process is carried out at low frame rates and the Nyquist-Shannon frequency limitation is overcome by adopting a down-sampling approach under the hypothesis that the vibration signal is characterized by a single known frequency component. The developed pseudo-stereo DIC system allows to obtain 3D full-field vibration measurements in a frequency range up to 4 kHz even with an available frame rate (at full resolution) of 178 fps. The effectiveness of the described approach has been verified by performing vibration measurements on a cantilever plate and a turbine blade.
关键词： Single low-speed camera,Vibration measurement,Down-sampling approach,Digital image correlation
更新于2025-09-19 17:15:36
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[IEEE 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Harbin, China (2019.8.11-2019.8.14)] 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Research on maximum power point contrast tracking of photovoltaic system based on improved particle swarm algorithm
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： prediction,sampling approach,unintentional electromagnetic radiator,Emission measurement,maximum directivity
更新于2025-09-19 17:13:59
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A Non-Isolated Step-up DC-AC Converter With Reduced Leakage Current for Grid-Connected Photovoltaic Systems
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： Emission measurement,sampling approach,prediction,unintentional electromagnetic radiator,maximum directivity
更新于2025-09-19 17:13:59
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[IEEE 2019 7th International Japan-Africa Conference on Electronics, Communications, and Computations, (JAC-ECC) - Alexandria, Egypt (2019.12.15-2019.12.16)] 2019 7th International Japan-Africa Conference on Electronics, Communications, and Computations, (JAC-ECC) - Broadside/Endfire Switched Beam Double Ridge-Gap Waveguide H-plane Horn Antenna
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： Emission measurement,sampling approach,prediction,unintentional electromagnetic radiator,maximum directivity
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) - Room temperature photoluminescence analysis of alkali treated single-stage thin Cu(In,Ga)Se <sub/>2</sub> absorber layers
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： prediction,sampling approach,unintentional electromagnetic radiator,Emission measurement,maximum directivity
更新于2025-09-16 10:30:52