A5028742574- HVDC Systems and Fault Protection
- Power Systems Fault Detection
- High-Voltage Power Transmission Systems
- Full-Duplex Wireless Communications
- Islanding Detection in Power Systems
- Advanced Sensor and Energy Harvesting Materials
- Direction-of-Arrival Estimation Techniques
- Innovative Energy Harvesting Technologies
- Microwave Engineering and Waveguides
- Microgrid Control and Optimization
- Transportation Planning and Optimization
- Magnetic Bearings and Levitation Dynamics
- Conducting polymers and applications
- Acoustic Wave Resonator Technologies
- Power Quality and Harmonics
- Lightning and Electromagnetic Phenomena
- Smart Grid and Power Systems
- Power System Optimization and Stability
- Smart Grid Security and Resilience
- Transportation and Mobility Innovations
- Antenna Design and Analysis
- Indoor and Outdoor Localization Technologies
- Aviation Industry Analysis and Trends
- Power Systems and Renewable Energy
- Urban Transport Systems Analysis
Northwest University
2025
Hangzhou Dianzi University
2023-2024
Xi'an Jiaotong University
2017-2024
Monash University
2024
Southeast University
2022
Chang'an University
2022
Huazhong Agricultural University
2021
Guilin University of Electronic Technology
2020
Southwest Jiaotong University
2018-2019
Ministry of Education of the People's Republic of China
2019
The result of single-ended traveling wave fault location method based on wavelet transform will be affected by false modulus maxima (WTMM) points. In this paper, distance/impedance information contained in the front is analyzed first. Then, fitting generalized logistic function proposed to extract information. Based results, a predictor-corrector proposed, which includes following content. First, coefficients zero-mode current are used estimate distance and impedance interval. Second,...
Hybrid AC/DC transmission grids require high-speed operation and high reliability for relay protection. Traditional derivative-based traveling wave protection methods have exposed the problems of low sensitivity reliability. In this paper, fault is analyzed considering attenuation, distortion, boundary effect DC line as well three converter types. The expressions initial are derived conclusions show that 1) at end formation a(1 - exp(-bt)); 2) index exponential function in expression related...
The performance of the traditional derivative-based non-unit traveling wave protection (TWP) in high voltage dc (HVDC) grids shows problem low-sensitivity when high-impedance faults occur. In this article, characteristics fault initial are analyzed first, two conclusions can be drawn: i) distortion degree is related to location, ii) amplitude impedance. Then a zero-sequence current fitting method proposed obtain parameters respectively reflecting impedance and distance. When occurs,...
The fast and selective protection using dc circuit breaker to break the fault current isolate faulty lines satisfies requirement of clearance in HVDC grids. However, traditional derivative-based traveling wave suffers from low-sensitivity problem when high-impedance faults occur. Based on analysis initial wave, it is concluded that distortion degree related location fault, amplitude impedance. Then a Levenberg-Marquart (LM) optimal approximation method proposed extract distance information...
High voltage dc grids are raised high-speed operation and high reliability requirement for relay protection. This article aims at proposing a protection scheme with speed, sensitivity, reliability. First, the symbolic expressions of line-mode fault component traveling wave in case internal external faults derived, which consist propagation term line boundary term. It is theoretically demonstrated that index greater than faults, independent impedance. Second, Levenberg–Marquardt algorithm...
To examine the form of harnesses from Shang and Western Zhou dynasties (16th–8th century B.C.) in China, this study analyzed black-brown granular thin-striped organic residues found on bronze 韅 (Xian, a leather belt around horse's abdomen) ornaments unearthed Shangmiao Cemetery Xitou Site Xunyi (Shaanxi, China). The were investigated by microscope, scanning electron microscopy (SEM), Raman spectroscopy (Raman), Fourier transform infrared (FTIR), Matrix-assisted laser desorption/ionization...
The high-speed and selective dc line protection method is required for the safe operation of HVDC grids. In this paper, expressions line-mode fault component voltage at end as well its first peak time (FPT) when different internal external faults occur are derived respectively. conclusion proves that FPT smaller than backward forward faults, which independent impedance type well. Then a FPT-based non-unit ultra-high-speed grids proposed. algorithm verified by four terminal ±400 kV MMC-HVDC...
Existing nonunit protection schemes inevitably require setting, which is a serious problem in practical engineering. Faults occurred at different fault zones will result equivalent models, therefore, the zone can be determined by recognizing model fits well with. In this article, "model recognition" idea introduced identification and "setting-less" method proposed. First, Peterson circuits when faults occur backward external zone, internal forward are presented, respectively. Accordingly,...
A novel miniaturized and reconfigurable coplanar waveguide (CPW) square-ring slot antenna is presented in this paper. The miniaturization achieved via a hybrid approach including ferroelectric varactor loadings, high dielectric constant materials, tuning stub for impedance matching. For the first time, nine shunt (FE) BST (Ba <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(1-x)</sub> Sr xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> TiO...
The multi-terminal hybrid LCC/MMC HVDC has been applied to overcome the simultaneous commutation failure problem caused by multi-infeed LCC-HVDCs in East China. high-speed and selectivity line protection method is required for system. In this paper, reflection refraction of fault traveling waves at different kinds terminals are characterized transfer functions. Then voltage as well its first peak time when internal external faults occur derived respectively. conclusion proves that line-mode...
Identifying and locating the single-pole-to-ground fault for non-effectively grounded DC distribution networks is highly challenging due to topology arrangement limitations grounding mode. To solve this problem, a ground section location method based on active detection approach proposed. Firstly, an additional control strategy in coordination with resonant branch setup proposed inject signals. Then, parameters of signals be injected are obtained after careful consideration ensure optimal...
This study presents a single-ended fault location method that does not need the information of remote-end system. As foundation proposed method, equations under different types are derived based on loops. The distance, impedance, and equivalent resistance inductance system considered as unknowns equation. Then equation can be solved using Gauss-Newton by which four obtained. Therefore, is sensitive to impedance parameters. A two-terminal 500 kV ac transmission line test built in PSCAD verify...
Abstract There exist problems of hard coordination and threshold setting as well low sensitivity in overcurrent relay due to the bidirectional small fault current when distributed generators are integrated into distribution network. This paper introduces ferrite rings (FRs) act boundaries feeders, a peak time voltage traveling wave‐based protection is proposed. The characteristics FRs analyzed their feasibility line boundary validated. internal external faults installed at both ends...
High voltage dc (HVDC) transmission, especially source converter (VSC)‐based HVDC transmission requires high‐speed operation for relay protection. However, traditional derivative‐based non‐unit travelling wave‐based protection (TWP) methods are sensitive to the fault impedance, resulting in low sensitivity case of high‐impedance fault. First, information containing wavefront is analysed based on frequency‐dependent parameters line and broadband characteristic fault‐point initial wave. It can...
As the second part of two series paper, protection scheme is proposed. First all theoretical analysis and threshold calculation methods are introduced. Aiming to problem that relay needs send alert signal instead trip in non-effectively grounded system when single pole ground fault occurs, a type identification method introduced based on ratio absolute values poles voltage derivatives. Then 1 mode developed feasibility design criterion voltages, impact sampling frequency, types, resistance...
Feeder automation is important to improve the reliability of power supply for distribution network. Existing voltage-time feeder scheme exists problems long fault processing time and upstream switches point need tolerate current twice sections experience two short outage. In this paper, a quick location isolation method network based on adaptive reclosing proposed. Three key technologies strategy are introduced, including phase segregated switch permanent magnet operating structure, selector...
This paper proposes multi-phase full wave and half type voltage resonant converters with automatic current balance against the LC elements variation. For converters, construction is very complicated because its operating frequency not stable. We have developed dual-phase four-phase technique of peak hold method saw-tooth signal. On other hand, important to make output ripple smaller, but it easy be imbalance variation CR elements. for both using in or four- phase converter.