8/6/2019 VRC Power Line de-Icing Video Narration Chinese.english

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Victor F. Petrenko, Professor of Engineering, Thayer School of Engineering

Dartmouth College, Hanover, NH 03755 603-646-0296

July 3, 2008.

3 Power Line De-icing tests, recorded in 3 video files. Explanation was given in Chinese

in the videos, transcription are given here in both English and Chinese.

Video- VRC Demonstration One (Separated Bundle) Power Line De-icing test 1

Youre attending a de-icing test with variable resistance conductor for distribution lines.

Here you can see a single loop of that conductor which has an Ampacity of 200 amps.

The current in both sides of the conductors is 60 amps. The conductor is constructed of3mm diameter aluminum strands and the conductors resistance can be electronically

switched from the very low value, that is when the conductor is in normal operation, to

resistance which can be 10, 25, or even 50 times greater, and this is used for rapid de-icing. The switching is done by control electronics placed at both sides of the conductor

section. Such a section can be as short as one span between two conducting poles, or

towers, and as long as 2 kms. In case of any failure or over-heating, the conductor

automatically returns to normal operations mode. This test is being conducted at -10 Cwith dense wet snow frozen in and around the conductor.

200

60 3

1025 50

2

10

The conductor further away from us, will be switched in the rapid de-icing mode;while the conductor close to us will remain in the normal operation mode.

Begin test.

End of test.

(De-icing time is from 1:25 to 4:32)

As you can see, the conductor in rapid de-icing mode is free of ice while the one further

away from us, which is the one in normal mode did not heat, and therefore, still has the

ice attached to it.

http://vimeo.com/27208892http://vimeo.com/27208892http://vimeo.com/27208892

8/6/2019 VRC Power Line de-Icing Video Narration Chinese.english

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Victor F. Petrenko, Professor of Engineering, Thayer School of Engineering

Dartmouth College, Hanover, NH 03755 603-646-0296

Video- VRC Demonstration Two (Stranded Bundle) (Power Line de-icing test2.)

Youre attending a de-icing test with variable resistance conductor for distribution lines.Here you can see a single loop of that conductor which has an Ampacity of 200 amps.

The current in both sides of the conductors is 120 amps. The conductor is constructed of1/8 `` diameter aluminum strands twisted around the steel core in the center, like the one

shown in the video. The conductors resistance can be electronically switched from thevery low value, that is when the conductor is in normal operation, to resistance which can

be 10, 25, or even 50 times greater, and this is used for rapid de-icing. The switching is

done by control electronics placed at both sides of the conductor section. Such a sectioncan be as short as one span between two conducting poles, or towers, and as long as 2

kms. In case of any failure or over-heating, the conductor automatically returns to normal

operations mode. This test is being conducted at -10 C with dense wet snow frozen inand around the conductor.

200120 1/8

1025 50

2

10

The conductor further away from us, will be switched in the rapid de-icing mode;

while the conductor closer to us will remain in the normal operation mode.

Begin test. Turn on the power. Both sides are in normal operation mode. Lets turn on therapid de-icing mode for the further away side.

End of test.

(de-icing time is from 2:05 to 3:20)

As you can see, the conductor in rapid de-icing mode is free of ice while the one furtheraway from us, which is the one in normal mode did not heat, and therefore, still has the

ice attached to it.

http://vimeo.com/27208974http://vimeo.com/27208974http://vimeo.com/27208974

8/6/2019 VRC Power Line de-Icing Video Narration Chinese.english

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