Dead-end-to-dead-end overhead electrical power transmission line with at least two different conductors, and method of selecting and installing the conductors.

Overhead electrical power transmission line

The invention provides an overhead construction process, which comprises the following steps of measuring data and calculating the wire length, wherein field data and the influencing quantity of the pressure welding length of a strain clamp are collected and the length of a strain insulator-string is measured; and calculating the wire length according to a formula, wherein L is the wire length; H is the conductor tension; omega is the weight of the conductor per unit length; l is the horizontal distance between the hanging points of the conductor; h is the altitude difference between the hanging points of the conductor; performing fixed-length manufacturing and machining wires, wherein the length of each conductor is calculated according to a wire length calculation formula, the conductor allocation is performed based on the control of the longest conductor of each phase, and the length of the conductor of each coil to be machined is determined; releasing the wires; and tightly hanging the wires. In the overhead construction process, the length of the required wire of each span can be measured directly on the ground, the installation position of a suspension clamp is demarcated, and thus the wires are suspended to achieve the preset completion sag without wire sag observation. Meanwhile, the overhead construction process and the quality level are improved, while the construction quality and the safety are ensured.

Assembly type overhead construction process

A high voltage outdoor power line includes at least one stranded conductor, and at least one damping device for damping mechanical Karman vibrations of the stranded conductor. The damping device includes a plurality of vibration dampers mounted on the stranded conductor by being suspended from respective suspension points on the stranded conductor, a spacing between the suspension points of two directly adjacent vibration dampers in a mounted state being smaller than half of a smallest anticipated wavelength of the Karman vibrations.

Outdoor power line having a damping device

Method of damping the vibrations of at least one pair of stay cables ( 4 a , 4 b ) of a civil engineering structure ( 1 ), in which the stay cables of said pair are linked by a damper ( 6 ) having a first stiffness in response to tensile stress and a second stiffness in response to compressive stress, the first stiffness being greater than the second stiffness.

Method of damping the vibrations of stay cables and associated system

Methods for selecting a conductor configuration of an overhead power transmission line tension section between two dead-end towers when the conductor configuration includes at least two different types of conductors. Geographical profile information and overhead power transmission line preferences are used along with predetermined selection rules when selecting the appropriate conductor configuration. Some examples of overhead power transmission line preferences include electrical characteristics and conductor sag between towers, while examples of selection rules include conductor costs and conductor tension.

Method for selecting conductors of an overhead power transmission line

In a vibration absorber for use with aerially suspended conductors and cables, there is described an improved vibration absorber wherein wind or turbulence induced vibrations resulting in travelling waves on conductors and cables are absorbed so as to prevent damage to or failure of conductors and related hardware due to fatigue. Known devices, particularly dampers and spacer dampers, attempt to control merely the amplitude of the waves produced on the conductor and are therefore ineffective in preventing the formation of such waves and the damage that may result. In this invention, a vibration absorber comprises a piston and cylinder device whereby a travelling wave displaces the piston or the cylinder relative to one another causing a fluid contained within the cylinder to be displaced through an orifice in the piston. The absorbing system thus defined has a mechanical dissipative impedance of value R to inhibit the reflection of a wave propagated on the conductor whereby the wave is absorbed. The value of R is in the range of 0.5√TM to 3.0√TM where T is the tension of the conductor and M is the mass of the conductor per unit length.

Overhead electrical conductor system including subspan oscillation and aeolian vibration absorber for single and bundle conductors

In a vibration absorber for use with aerially suspended conductors and cables, there is described an improved vibration absorber wherein wind or turbulence induced vibrations resulting in travelling waves on conductors cables are absorbed so as to prevent damage to or failure of conductors and related hardware due to fatigue. Known devices, particularly dampers and spacer dampers, attempt to control merely the amplitude of the waves produced on the conductor and are therefore ineffective in preventing the formation of such waves and the damage that may result. In this invention, a vibration absorber comprising a piston and cylinder device whereby a travelling wave displaces the piston orthe cylinder relative to one another causing a fluid contained within the cylinder to be displaced through an orifice in the piston. The absorbing system thus defined has a mechanical dissipative impedance of value R to inhibit the reflection of a wave propagated on the conductor whereby the wave is absorbed. The value of R is in the range of .5 TM to 2.0 TM where T is the tension of the conductor and M is the mass of the conductor per unit length.

Vibration absorber for aerially suspended conductors and cables

In a vibration absorber for use with aerially suspended conductors and cables, there is described an improved vibration absorber wherein wind or turbulence induced vibrations resulting in travelling waves on conductors cables are absorbed so as to prevent damage to or failure of conductors and related hardware due to fatigue. Known devices, particularly dampers and spacer dampers, attempt to control merely the amplitude of the waves produced on the conductor and are therefore ineffective in preventing the formation of such waves and the damage that may result. In this invention, a vibration absorber comprising a piston and cylinder device whereby a travelling wave displaces the piston or the cylinder relative to one another causing a fluid contained within the cylinder to be displaced through an orifice in the piston. The absorbing system thus defined has a mechanical dissipative impedance of value R to inhibit the reflection of a wave propagated on the conductor whereby the wave is absorbed. The value of R is in the range of to where T is the tension of the conductor and M is the mass of the conductor per unit length.

Olaf Nigol

Papers

Overhead electrical conductor system including subspan oscillation and aeolian vibration absorber for single and bundle conductors

Vibration absorber for aerially suspended conductors and cables

Subspan oscillation and aeolian vibration absorber for single and bundle conductors