SU1631649A1 - Pendulum damper for bunch of split wires of aerial power line - Google Patents

Abstract

The invention relates to electric power industry, in particular, to the systems of vibration suppression of split wires. The purpose of the invention is to increase the reliability of the wire bundle by preventing fatigue failures of the bundle and strut wires. Rotary dampers are simultaneously vibration dampers of split wires due to the proposed spatial structure of the elements, consisting of two concentrated struts located at a predetermined distance from one another and connected to a two-support balcony for placing cargoes, such as: does not transmit vibrations along the wire, in which the half-wave length does not fit an integer number of times between the spacers, as a result, the vibration does not reach a dangerous level at which The fastening of vibration dampers to the wire would accumulate fatigue damage. 1 il., 1 s.p. .

Description

The invention relates to electric power engineering, mainly to air power transmission lines (OHL), in particular, to damping systems of split wires.

The purpose of the invention is to increase the reliability of the beam. Wires by preventing fatigue damage of the beam wires and struts.

The drawing shows a pendulum damper of split wires of overhead power lines attached to a bundle of phase splitting wires.

A load represented as a combination of several components 1 with the center of mass c. the lower point of a circle located in a plane perpendicular to the axis of the beam and passing through the centers of the section of the beam wires is suspended on a double support beam | 2 connecting two concentrated struts. 3, mounted on wires 4 at a distance of.

The principle of operation of the pendulum damper according to the invention is as follows.

In a span of length 1 of a phase of radius r, split into JU wires, there are ί pendulum loads with masses M _(| M'j ·, centers of gravity.

which are respectively at distances Xp ..., x £ from the left end of the span. The load with the number j (j1,. ,,, J) is placed on a double-beam, which is fixed on two concentrated struts, with a total mass mj. If, m is the linear mass of the wire with ice, and T is the traction of one wire in the beam, then the ratio of the frequency W kJ of natural torsional vibrations to the frequency of natural vertical vibrations for the form with the number d (d = 1, 2, 3, 4) determined from ~ the following equality:

ι ₊ ______! ___ 1 ^{1 +}

X

Wkd ^w W where g is the gravitational acceleration. According to equality, the efficiency of the absorber will be determined by the second term in. on the right-hand side of (1), since it is this term that characterizes the frequency detuning of the eigenstates of vertical and torsional vibrations together with the damping of vibrations for 3 * AC 400/51.

3

Ϊ2 ’4’ split wire bodies of dance.

Specific example: pendulum damper: three-wire bundle

In a span of 294.2 m in length, there are 6 pendulum dampers of oscillations 1 * 1 13 ““ at a distance -, -, -, ^ of the span length from one of the ends. Each absorber is a load weighing 20 kg, four identical components 1 with masses along its kg, the center of mass of which is found on the axis of the lower beam wire. The components 1 of the load are suspended by a double support beam 2, which is mounted on two concentrated struts 3 weighing 2.5 kg each, located at a distance of ^{β β} 0.6 m from each other.

If the linear mass of the wire with goK and ice is equal to 1.957 -, the splitting step is 0.4 m, the tension of one wire is 31400 N, then the ratios of the frequencies of the natural torsional and vertical “- Wkd oscillations are a bundle of three wires ^w bd dots, estimated according to the formula (1), for 1, 2, 3, 4 forms are 2.195, respectively; 1.307; 1,130;

1,060. Thus, the use of pendulum vibration absorbers eliminates one of the necessary conditions for the existence dancing coincidence frequency identical forms vertical and torsional vibrations, ι The experiments showed that the frequency detuning, which is reached ⁰ "when installing dampers Guy construction described in the test span, is sufficient to a decrease of about 2 times. the amplitudes of the two-half-wave 'oscillations established in a transverse wind _: split-phase vibrations equipped with aerodynamic nozzles simulating icy deposits. In addition, pendulum dampers with a spatial design, containing 2 concentrated struts located at a distance of 0.6 m and connected by a double support beam, are a frequency filter (damper) of vibration for all its forms, except for those with a distance of 0, 6 m fits an integer number of half-waves. The forms of vibration realized on the overhead lines have half-wavelengths from 1 to 20 m and, therefore, any of them is attenuated by the spatial structure of the vibration damper with a distance between the concentrated spacers of 0.6 m.

Technical Efficiency Retention consists in the fact that through the use of a pendulum vibration damper of split wires of a spatial structure consisting of two concentrated spacers connected by a double support beam on which the load is attached, fatigue damage of the beam wires and spacers is prevented, and the dances of the wires are successfully quenched.

Claims (2)

Claim 1. A bundle of split wires of an overhead power line with a pendulum damper containing a load with a center of mass located under the longitudinal axis of the beam of split wires and a main concentrated spacer that attaches the load to the bundle of split wires, characterized in that, in order to increase reliability 1Q of work by preventing fatigue damage of the beam wires and spacers, it is equipped with an additional concentrated spacer and a double support beam installed between the main 15 and additional concentrated struts, on which the specified load is fixed, while the center of mass of the load is located in a vertical plane passing through the longitudinal 20 axis of the bundle of split wires at a distance from the longitudinal axis of the bundle equal to or greater than the radius of the bundle of split wires; 2. A bundle of split wires 25 pop. 1, characterized in that, in order to increase the reliability of the double-beam, the load is made in the form of separate components.