Study of Mitigation Measures of Galloping in the Use of Interphase Spacers
- Approach to Adopt Lightweight Interphase Spacers -
Electric Power,
Information Communications Technology,
Civil Engineering Research Section
Interphase spacers are common as a galloping control for transmission lines, but when the interphase spacers are installed to exiting transmission lines, they may burden towers due to increased conductor tension, and the towers may need to be reinforced.
Therefore, we have studied lightweight interphase spacers to reduce the burden on towers.
Outline of the Study
Most of the interphase spacers are now made of non-porcelain (polymer), and they are much lighter than conventional porcelain interphase spacers. Even so, they weigh as much as about 190 kg per unit for 275 kV system transmission lines.
In this study, the core (made of FRP) of the interphase spacer are made thinner and much lighter. We are now evaluating the effects of mitigation of galloping, mechanical strength (compressive strength and bending strength), and electric strength (insulation performance, characteristics under contamination conditions, and snow and salt-resistant performance) in the case where these lightweight interphase spacers are installed.
Fig.1 Interphase spacer (Left: Usual type Right: Lightweight type)
Fig.2 An example of analysis simulation (300m
3 span with three lightweight interphase spacers)
Plan for the Future
We will continue to evaluate the galloping vibration property, mechanical strength, and electrical strength, and aim at adopting it to our 275kV system transmission lines in the FY 2009.
We will also seek a way to lighten the spacers besides making them thinner; weigh galloping vibration property in each facility condition； and study the optimal kind, number, and location of interphase spacers.
