Ice Accretion of Glaze Loads Model on Wires of Power Transmission Lines

2011 ◽  
Vol 189-193 ◽  
pp. 3225-3229
Author(s):  
Chun Cheng Liu ◽  
Jiao Liu
Keyword(s):  
Wind Speed ◽  
Transmission Lines ◽  
Prediction Models ◽  
Power Transmission ◽  
Time Dependent ◽  
Ice Accretion ◽  
Power Transmission Lines ◽  
Collision Efficiency ◽  
Accretion Model ◽  
Median Volume

In connection with the process of glaze ice, prediction models about height and thickness of ice coating under uniform and non-uniform ice accretion of wire are presented by taking into account local collision efficiency, freeze coefficient and collection coefficient based on the existing model at home and abroad. The time-dependent ice models on the conditions of different median volume diameter of super-cooled droplets, wind speed and wire diameter are analyzed. Compared with the existing model, the proposed ice accretion model performed well in predicting ice’s weight and thickness. At the same time, it can give some lights on ice disaster and anti-icing design for power transmission lines.

Experimental Researches on Micro-Droplet Freezing on a Solid Surface Under Atmospheric Conditions: Part I

2008 ◽  
Author(s):  
Heyun Liu ◽  
Xiaohui Ma
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Electrostatic Force ◽  
Droplet Diameter ◽  
Ccd Camera ◽  
Freezing Process ◽  
Ice Accretion ◽  
Power Transmission Lines ◽  
Atmospheric Conditions ◽  
Air Stream

Atmospheric ice accretion on structures is a problem of fundamental importance to a number of industries. Examples of engineering problems caused by ice accretion involving aircraft, power transmission lines, telecommunication towers, electrical railway contact-wires, and other structures. Under atmospheric icing conditions two basic types of ice may form; rime or glaze. The supercooled micro-droplets in clouds are an important factor in icing. The objective of this study was to develop a new experimental method to investigate a single supercooled micro-droplet freezing process, in order to better understand the mechanism of rime or glaze ice accretion. The experimental device and principles are described in this paper. The experimental set has two small cold rooms, which is separated by a board with a central hole. A droplet with diameter of 15∼40 μm, temperature of 0∼−5°C was levitated in the cold air stream by electrostatic force. A CCD camera tracked its trace. The air temperature is from 0∼−10°C, the micro-droplet diameter is from 15∼40μm, and its temperature is from 0∼−5°C in the experimental study. This article focused on the experimental set and the experimental principles, and the next article will focus on the experimental data analysis.

Ice Accretion Cause and Mechanism of Glaze on Wires of Power Transmission Lines

2011 ◽  
Vol 189-193 ◽  
pp. 3238-3242 ◽  
Author(s):  
Chun Cheng Liu ◽  
Jiao Liu
Keyword(s):  
Electric Field ◽  
Fluid Mechanics ◽  
Transmission Line ◽  
Transmission Lines ◽  
Power Transmission ◽  
Ice Accretion ◽  
Power Transmission Lines ◽  
Field Coupling ◽  
Ice Disaster ◽  
Current Electric Field

The cause of ice accretion of transmission line and ice accretion mechanism are both summarized systematically. The mechanism of ice coating of wire caused by thermodynamics, fluid mechanics and the current electric field coupling is pointed out. In connection with the process of glaze ice, the existing models at home and abroad for the prediction of height and thickness of ice coating are summarized and analyzed, it can give some advises on further study of ice accretion prediction and some lights on ice disaster and anti-icing design for power transmission lines.

METHOD OF SYNTHESIS OF CLOSED-LOOP SYSTEMS OF ACTIVE SHIELDING MAGNETIC FIELD OF POWER TRANSMISSION LINES

2016 ◽  
Vol 2016 (4) ◽  
pp. 8-10 ◽  
Author(s):  
B.I. Kuznetsov ◽  
◽  
A.N. Turenko ◽  
T.B. Nikitina ◽  
A.V. Voloshko ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Transmission Lines ◽  
Closed Loop ◽  
Power Transmission ◽  
Power Transmission Lines ◽  
Closed Loop Systems ◽  
Active Shielding

scholarly journals Time-Multiplexed Self-Powered Wireless Current Sensor for Power Transmission Lines

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1561
Author(s):  
Hao Chen ◽  
Zhongnan Qian ◽  
Chengyin Liu ◽  
Jiande Wu ◽  
Wuhua Li ◽  
...  
Keyword(s):  
Energy Harvesting ◽  
Transmission Line ◽  
Transmission Lines ◽  
Power Transmission ◽  
Current Measurement ◽  
Current Sensor ◽  
Power Transmission Line ◽  
Power Transmission Lines ◽  
Current Sensing ◽  
Self Powered

Current measurement is a key part of the monitoring system for power transmission lines. Compared with the conventional current sensor, the distributed, self-powered and contactless current sensor has great advantages of safety and reliability. By integrating the current sensing function and the energy harvesting function of current transformer (CT), a time-multiplexed self-powered wireless sensor that can measure the power transmission line current is presented in this paper. Two operating modes of CT, including current sensing mode and energy harvesting mode, are analyzed in detail. Through the design of mode-switching circuit, harvesting circuit and measurement circuit are isolated using only one CT secondary coil, which eliminates the interference between energy harvesting and current measurement. Thus, the accurate measurement in the current sensing mode and the maximum energy collection in the energy harvesting mode are both realized, all of which simplify the online power transmission line monitoring. The designed time-multiplexed working mode allows the sensor to work at a lower transmission line current, at the expense of a lower working frequency. Finally, the proposed sensor is verified by experiments.

scholarly journals Decentralized Estimation of Two-port Equivalents for Power Transmission Lines

IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Vedanta Pradhan ◽  
O. D. Naidu ◽  
Sinisa Zubic ◽  
Patrick Cost
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Power Transmission Lines ◽  
Decentralized Estimation
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