Results 221 to 230 of about 9,007 (253)

Emergency Control Strategy of Ultra-low Frequency Oscillations Based on WAMS

2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia), 2019
In this paper, an emergency control strategy of ultra-low frequency oscillations (ULFO) is presented. The multi-signal Prony algorithm is used to identify frequency signals from WAMS. Then the criterion of ULFO is proposed based on the Prony analysis results.
Qin LIU, Gang CHEN, Baisi LIU, Yudong ZHANG, Chuyu LIU, Zhuolin ZENG, Chengwei FAN, Xiaoyan HAN   +7 more
openaire   +1 more source

Mode Identification and Damping Torque Analysis of Ultra-Low Frequency Oscillations

2019 IEEE Sustainable Power and Energy Conference (iSPEC), 2019
After the asynchronous interconnection of Yunnan and South China Power Grid, a long period of ultra-low frequency oscillation occurred, which seriously affected the safe and stable operation of the system. This paper presents the damping analysis of hydraulic turbine governing systems under ultra-low frequency oscillations.
Junfeng Zhang, Yanjun Zhao, Yanhui Xu, Zhen Li, Wei Bai   +4 more
openaire   +1 more source

Analysis of ultra-low frequency oscillation in yunnan asynchronous sending system

2017 IEEE Power & Energy Society General Meeting, 2017
Yunnan power grid has a large-scale hydropower station whereby the power generated at the station is been transmitted via high-voltage direct current (HVDC) transmission lines under asynchronous operation mode. In the system performance test of Yunnan asynchronous operation, 0.05 Hz ultra-low frequency oscillation occurred in the grid.
Yiping Chen, Yingshang Liu, Zhuoyao Tang, Jun Hou, Yong Zhang, Weike Mo, Haoyong Chen   +6 more
openaire   +1 more source

Ultra Low-Frequency Oscillations of a Solar Filament Observed by the GONG Network

Solar Physics, 2016
The data of ground-based telescopes of the Global Oscillation Network Group (GONG) obtained in the $\mathrm{H}\upalpha$ line provide an opportunity to study the long-period oscillations of chromospheric ...
V. I. Efremov, L. D. Parfinenko, A. A. Solov’ev   +2 more
openaire   +1 more source

Ultra low-power, -area and -frequency CMOS thyristor based oscillator for autonomous microsystems

2015 Nordic Circuits and Systems Conference (NORCAS): NORCHIP & International Symposium on System-on-Chip (SoC), 2015
In this paper we present a minimal sized CMOS thyristor based oscillator, which is able to provide a clock signal of $$\approx$$ź20 Hz. The oscillator was designed as a timer or clock generator for autonomous microsystem applications. The chip area of the oscillator is 18 µm by 35 µm and it is able to run for more than 10 min when supplied from a 10 nF
Dominic A. Funke, Jürgen Oehm, Pierre Mayr, Thomas Maeke, John S. McCaskill, Abhishek Sharma 0004, Lukas Straczek   +6 more
openaire   +2 more sources

An ultra-low frequency ring oscillator with programmable tracking using a phase-locked loop

2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), 2012
This paper presents a programmable ultra-low frequency ring oscillator designed in a 0.5µm CMOS technology with 3.3 V power supply. In normal operation, the oscillator produces a periodic signal without external inputs (other than power and ground).
Tsung-Hsueh Lee, Pamela Abshire
openaire   +2 more sources

Low-frequency noise properties of SiGe HBT's and application to ultra-low phase-noise oscillators

IEEE Transactions on Microwave Theory and Techniques, 1998
This paper presents an extensive electrical characterization of Si/SiGe/Si heterojunction bipolar transistors (HBT's) grown by molecular beam epitaxy (MBE). These devices are designed for microwave and millimeter-wave applications since they present a maximum oscillation frequency in the 40-GHz range. The processing technology, featuring a high-quality
B. Van Haaren, M. Regis, O. Llopis, L. Escotte, A. Gruhle, C. Mahner, R. Plana, J. Graffeuil   +7 more
openaire   +1 more source

Ultra-low power frequency synthesizer based on a dual-locking ring oscillator

2016 13th IEEE International Conference on Solid-State and Integrated Circuit Technology (ICSICT), 2016
An ultra-low power frequency synthesizer based on a 28-nm CMOS dual-voltage controlled ring oscillator is presented. The technological dispersion and temperature effects are tackled thanks to a Delay locked loop (DLL) which sets a coarse tuning voltage.
Yann Deval, Yoan Veyrac, Herve Lapuyade, Francois Rivet   +3 more
openaire   +1 more source

Suppression Strategy of Ultra-Low Frequency Oscillation in Yunnan Power Grid with BESS

2019 North American Power Symposium (NAPS), 2019
Many problems related to power system frequency have occurred in Yunnan Province ─a province in southwestern China with high proportion of hydro-turbine generators. Yunnan Power Grid is a typical direct-current (DC) sending grid and the installed capacity of hydro-generators has accounted for more than 70% of the total capacity after asynchronous ...
Yixuan Chen, Yuanxiao Zhao, Guangchao Geng, Quanyuan Jiang, Wenlong Liu, Lingfang Li   +5 more
openaire   +1 more source

Oscillation Source Location of Ultra-low Frequency Oscillations Based on Random Forest Algorithm

2022 International Conference on Cyber-Physical Social Intelligence (ICCSI), 2022
Tao Zhou, Jie Sun, Hao Quan, Dexu Zou, Qingjun Peng   +4 more
openaire   +1 more source