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11th China Satellite Navigation Conference, CSNC 2020

作者： Zheng, Yingchun Zhang, Jianwei State Key Laboratory of Satellite Navigation System and Equipment Technology No.589 Zhongshan West Road Qiaoxi District Shijiazhuang CityHebei Province China The 54th Research Institute of CETC Shijiazhuang China

ISBN: (纸本)9789811537141

Using real-time broadcast ephemeris to calculate satellite orbit information and clock parameters is an important calculation work in GNSS terminal positioning solution. Considering the development trend of GNSS terminal’s low power consumption and Soc, the application and implementation of satellite orbit interpolation algorithm in GNSS receiver are analyzed. From the aspects of computing efficiency, application strategy and continuity, the performance of interpolation algorithm in GNSS real-time operation is analyzed. An implementation of GNSS satellite orbit interpolation algorithm is given to meet the needs of GNSS high frequency sub-location applications. The calculation results show that the method can fit the position and velocity parameter information of GNSS satellites orbit operation in real time. The satellite position accuracy is better than 1e-4 m and the velocity accuracy is better than 1e-3 m/s. It basically meets the requirements of high-frequency real-time calculation of GNSS receivers, and continuity. © 2020, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Global positioning system

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Evaluation on Suitability of Oil and Gas Zoning in Nansha Sea 7th

Evaluation on Suitability of Oil and Gas Zoning in Nansha Se...

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7th International Conference on Geoinformatics in Sustainable Ecosystem and Society, GSES 2019, and 1st International Conference on Geospatial Artificial Intelligence for Urban Computing, GeoAI 2019

作者： Ji, Min Liu, Xiaojia Zhang, Yu Su, Fenzhen Sun, Yong College of Geomatics Shandong University of Science and Technology Qingdao266590 China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China

ISBN: (纸本)9789811561054

The Nansha Sea (NSS) is rich in oil and gas resources, which has caused great concern to neighboring countries and large-scale mining that brings a huge negative impact on the maintenance of China’s marine right. In lack of marine functional zoning of the NSS and natural/social considerations in suitability evaluation of oil and gas zoning, this paper constructed a suitability evaluation model that involves resource conditions, topographic conditions, climate conditions, hydrological conditions, natural disasters, traffic conditions, social conditions. Based on the comprehensive score, the suitability was divided into four grades including the high suitable, the suitable, the less suitable and the unsuitable. Results showed that high suitable area are mainly distributed in Beikang basin;suitable area are mainly distributed in Lile basin, East Nanwei basin, Zhongjiannan basin and others in West Nanwei basin;less suitable area are mainly distributed in Nansha Trough basin and others are in West Nanwei basin. The paper would be helpful to the future exploration of oil and natural gas in the NSS. © 2020, Springer Nature Singapore Pte Ltd.

关键词： Energy resources

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An online measurement method for noise-source impedance of electrical equipment

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Progress In Electromagnetics Research C 2020年 100卷 95-103页

作者： Du, Mingxing Li, Yang Wang, Hongbin Ouyang, Ziwei Wei, Kexin Tianjin Key Laboratory of Control Theory & Applications in Complicated System Tianjin University of Technology Tianjin China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology Tianjin China

The paper presents a method of extracting noise source impedance of electrical equipment under working condition. Firstly, based on the theory of two-port network, the measurement method of noise impedance is analyzed theoretically, and the injection probe and receiving probe are calibrated by two known resistors. No special calibration fixture is needed to calibrate the injection probe and receiving probe. Secondly, the port structure of the noise impedance measurement method is analyzed, and the noise source impedance is calculated by using the theory of microwave transmission. Compared with the traditional method, this method does not require calibration fixture and simplifies the experimental process. Finally, passive devices and active systems are tested respectively, and the experimental results show that the method is effective and feasible. © 2020, Electromagnetics Academy. All rights reserved.

关键词： Probes

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A Recognition Method of Excitation Waveforms for Core Loss Analysis of Renewable Generation Converter Based on Magnetic Flux Density Peak Location and Feature-Optimized Random Forest

A Recognition Method of Excitation Waveforms for Core Loss A...

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Energy, Electrical and Power Engineering (CEEPE), International Conference on

作者： Shuolin Zhang Ye Tao Yaci Yu Jiongcheng Yan Chao Song Pengming Zhai Chihan Zhou Lisen Feng School of Electrical Engineeringm Shandong University Jinan China Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University Jinan China Technology Co. Ltd Shandong Future Intelligent Jinan China Wenshan Power Supply Bureau of Yunnan Power Grid Co. Ltd. Wenshan China State Grid Kunming Power Supply Company Kunming China Shandong Electric Power Engineering Consulting Co. Ltd. Jinan China

ISBN: (数字)9798331521844

ISBN: (纸本)9798331521851

The study of core loss characteristics is essential for improving the performance of renewable generation converters, and the classification and identification of excitation waveforms is fundamental to analyzing core loss characteristics. The excitation waveform is primarily characterized by the temporal distribution pattern of magnetic flux density. To accurately identify different excitation waveforms, it is necessary to extract feature variables that reflect the temporal distribution of the magnetic flux density and select an appropriate artificial intelligence algorithm to establish a classification and recognition model for excitation waveforms. However, current feature extraction methods have difficulty capturing deep features beyond traditional characteristics, which results in inaccurate classification outcomes. In response, a classification and recognition method for excitation waveforms based on magnetic flux density peak location and feature-optimized random forest is proposed. Firstly, the magnetic flux density peak location after being normalized along the time axis is extracted as a deep feature. Secondly, an excitation waveform classification model is established using artificial intelligence methods such as feature-optimized random forest. Finally, the effectiveness of the proposed method is verified using magnetic flux density sampling data from four types of core materials as examples.

关键词： Magnetic flux density Renewable energy sources Accuracy Magnetic cores Core loss Feature extraction Robustness Classification algorithms Artificial intelligence Random forests

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Research on Non-contact Pollution Monitoring Method of Composite Insulator Based on Space Electric Field 7

Research on Non-contact Pollution Monitoring Method of Compo...

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7th IEEE International Conference on High Voltage Engineering and Application, ICHVE 2020

作者： Zhang, Dongdong Liu, Jin Fengbo, Tao Huang, Xiaoning Yang, Chengshun Zhang, Zhijin School of Electrical Engineering Nanjing Institute of Technology Nanjing China Electric Power Research Institute State Grid Jiangsu Electric Power Co. Ltd. Nanjing China State Key Laboratory of Power Transmission Equipment System Security and New Technology Chongqing University Chongqing China

ISBN: (纸本)9781728155111

Insulator contamination directly threatens the safe and stable operation of the overhead line. Through spatial electric field monitoring, it is expected to realize insulator pollution condition monitoring and contamination flashover warning in a non-contact way. So in this paper, the spatial electric field distribution characteristics of 110 kV composite insulators are simulated, where the effects of different surface states and their discharge levels on the spatial electric field of insulators are analyzed. On this basis, a non-contact monitoring method for composite insulator pollution based on the spatial electric field is proposed. The results show that there are significant differences in the spatial electric field of the composite insulator among three conditions of clean, pollution layer wetting, and dry band arcing. With the increase of pollution layer wetting and dry band arcing, it would lead to an increase of the amplitude of the spatial electric field of the insulator. It is feasible to identify the degree of pollution layer wetting as well as dry band arcing of the insulator string, by fixed-point monitoring the spatial electric field signal at the cross-strand of d = 0.5 m and directly opposite the last three positions. Research results can provide references for the online monitoring of overhead line pollution insulators and its flashover warning. © 2020 IEEE.

关键词： Insulator contamination

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A High Linearity TH circuit for 1GHz Pipeline ADC in 65nm CMOS 15

A High Linearity TH circuit for 1GHz Pipeline ADC in 65nm CM...

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15th IEEE International Conference on Solid-state and Integrated Circuit technology, ICSICT 2020

作者： Wu, H.J. Zeng, Y.P. Xing, X.L. Lin, N. Li, Q. Fudan Microelectronics Co. Ltd Shanghai200433 China No.58 China Electronic Technology Group Corporation Wuxi214035 China State Key Laboratory of Asic and System Fudan University Shanghai200433 China

ISBN: (纸本)9781728162355

A 3.3/2.5V/1.2V high linearity track-And-hold (TH) circuit for 1GHz Pipeline analog to digital converter (ADC) in 65nm CMOS is implemented. It includes the two input buffer with source follower, bias and common mode voltage and generated part, input-impedance matching network and SPI part. Input-impedance matching network include a 50-O /100-O /200-O resistor controlled with SPI. The simulated results show that the SFDR and SNDR of the input buffer can get 89dB and 88dB, respectively. The power consumption is 158mW with typical 3.3V/2.5V/1.2V supply. © 2020 IEEE.

关键词： Pipelines

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A Matching Based Escape Routing Algorithm with Variable Design Rules and Constraints 23

A Matching Based Escape Routing Algorithm with Variable Desi...

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Proceedings of the 60th Annual ACM/IEEE Design Automation Conference

作者： Qinghai Liu Disi Lin Chuandong Chen Huan He Jianli Chen Yao-Wen Chang Center for Discrete Mathematics Fuzhou University Fuzhou China and Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou Fujian China Department of Microelectronics Fuzhou University Fuzhou China Hangzhou Huawei Enterprises Telecommunication Technologies Co. Ltd Hangzhou China State Key Lab of ASIC & System Fudan University Shanghai China Graduate Institute of Electronics Engineering National Taiwan University Taipei Taiwan and Department of Electrical Engineering National Taiwan University Taipei Taiwan

ISBN: (纸本)9798350323481

Escape routing is a critical problem in PCB routing, and its quality greatly affects the PCB design cost. Unlike the traditional escape routing that works mainly for the BGA package with unique line width and space, this paper presents a high-performance escape routing algorithm to handle problems with variable design rules and manual constraints, including variable line widths/spaces, the neck mode of wires, and the pad entry for differential pairs. We first propose a novel obstacle-avoiding method to project pins to the boundary and construct a channel projection graph. We then construct a bi-projection graph and propose a matching-based hierarchical sequencing algorithm to consider manual constraints. We perform global routing for each pin/differential pair by congestion-avoiding path initialization and rip-up and reroute path optimization. Finally, we complete detailed routing in every face, ensuring the wire angle and pad entry constraints. Experimental results show that our algorithm can achieve 100% routability without any design rule violation for all given industrial PCB instances, while two state-of-the-art routers cannot complete routing.

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Multi-GNSS simulation and its positioning performance for static and dynamic users

Multi-GNSS simulation and its positioning performance for st...

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International Symposium on Autonomous systems (ISAS)

作者： Kun Li Mengzhi Gao Shuaiyong Zheng Xuanwen Wang Xiaoqin Jin Peng Yang Jianlei Yang Jing Lu Gaole Yao School of Integrated Circuit Science and Engineering Tianjin University of Technology Tianjin China College of Artificial Intelligence Nankai University Tianjin China School of Computer Science and Engineering Tianjin University of Technology Tianjin China State Key Laboratory of Satellite Navigation System and Equipment Technology The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang China Land Satellite Remote Sensing Application Center Ministry of Natural Resources Beijing China Tianjin AtoN Division The Navigation Guarantee Centre of North China Sea Tianjin China

Global navigation satellite system plays an important role in military and civil fields, providing global positioning, navigation and timing services in real time. Unfortunately, the services provided by single constellation or double constellations cannot meet the requirements of high-level navigation, and there are still some problems such as low positioning accuracy and low number of visible satellites at specific circumstances to be solved. In this paper, multi-GNSSs are constructed and their global positioning performance is analyzed with respect to static and dynamic users. Results show that with more constellations, the position dilution of precision is decreased, and the number of visible satellites and the positioning accuracy are improved, which reveals that compared with single constellation or double constellations, multi-GNSSs can obviously improve the positioning performance. The methodology proposed can serve as a technical reference for national integrated PNT systems.

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Improved Scheme for Single-Ground Fault Suppression Based on Grounded-Fault Transfer Device 7

Improved Scheme for Single-Ground Fault Suppression Based on...

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7th IEEE International Conference on High Voltage Engineering and Application, ICHVE 2020

作者： Liu, Hongwen Wang, Ke Ran, Jiaquan Yang, Qing He, Lewei Electric Power Research Institute Yunnan Power Grid Co. Ltd. Kunming China School of Electrical Engineering State Key Laboratory of Power Transmission Equipment System Security and New Technology Chongqing China

ISBN: (纸本)9781728155111

For the sake of reliability of power distribution, medium voltage distribution networks apply small-current earthed mostly. However, traditional resonant earthed methods applied arc suppression coil have poor performance as capacitive current growing rapidly. In order to eliminate single-ground fault effectively, a full-compensation method based on controllable voltage source is therefore proposed and grounded-fault transfer device is applied. Controllable voltage source proposed based on high power electronic devices could inject compensation voltage with specific phase and amplitude into neutral point, which could realize single-ground fault self-extinguish. And grounded-fault transfer device applied in the improved scheme could improve the efficiency of full-compensation method. The verification of the improved scheme for single-ground fault full-compensation is supported by PSCAD/EMTP. Results acquired indicate that the improved scheme for single-ground fault suppression method based on grounded-fault transfer device could eliminate single-ground fault efficiently. © 2020 IEEE.

关键词： Electric grounding

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Influence of manufacturing errors of bearing components on rotational accuracy of cylindrical roller bearings

Research Square

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Research Square 2021年

作者： Yu, Yongjian Li, Jishun Xue, Yujun School of Mechatronics Engineering Henan University of Science and Technology Luoyang471003 China Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang471003 China Luoyang LYC Bearings Co. Ltd State Key Laboratory of Aviation Precision Bearings Luoyang471039 China

Understanding the influence of bearing component manufacturing errors and roller number on the rotational accuracy of rolling bearings is crucial in the design of high precision bearings. The rotational accuracy of an assembled bearing is dependent upon roller number and manufacturing error of the bearing components. We propose a model for calculating the rotational accuracy of a cylindrical roller bearing;we experimentally verified the effectiveness of the model in predicting the radial run-out of the inner ring proposed in the previous paper in this series. We sought to define the key contributing factors to the rotational accuracy by studying both the influence of the coupling effect of the roller number and the influence of the manufacturing errors in the inner raceway, outer raceway, and rollers on the motion error. The model and results will help engineers choose reasonable manufacturing tolerances for bearing components to achieve the required rotational accuracy. © 2021, CC BY.

关键词： Rollers (machine components)

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