Four-phase overhead transmission lines have special advantages in high phase order transmission lines, because of the good symmetry and the simple structure of its lines and poles.

四相架空输电线路对称性好，线路及杆塔结构简单，在多相输电线路中具有独特的优势。

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With the traffic situation changed, the method makes the phase order, the ratio of green signal and the cycle adaptively change.

本方法实现了相位顺序、绿信比、周期均随着交通条件的变化而自适应变化。

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With the traffic situation changed, the method makes the phase order, the ratio of green signal and the cycle adaptively change.

本方法实现了相位顺序、绿信比、周期均随着交通条件的变化而自适应变化。

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