RU2522423C2 - Mobile current generator for ice melting on wires of overhead transmission lines - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: application: in the field of electric engineering. A mobile current generator comprises an electric energy source in the form of two diesel generators of alternating current, an alternating current rectifier, conductors with terminals to connect it to the overhead transmission line wires and bus lines to connect wires of the overhead transmission line in the span between the supports as per an ice-melting scheme, at that by means of a semiconductor converter with a control circuit ensuring a mode of the electric energy source the mild operation mode is achieved for the diesel generators, the semiconductor converter provides the preset constant current for ice melting notwithstanding electrical resistance of the wire circuits and earthing circuits and its circuit design ensures ice melting at the section equal to the length of two spans for the overhead transmission lines on phase wires and the lightening protection cable, including design of the lightening protection cable with earthing made at each support.

EFFECT: improving reliability and safety.

2 dwg

Description

FIELD OF THE INVENTION

The invention relates to the equipment of overhead power lines (VL) of voltage up to 220 kV and higher, located in areas with possible icy formations on the wires.

A mobile current generator for melting ice has a number of advantages compared to stationary means for melting ice on OL wires, which allows for reliable operation of power supply networks with lower costs.

State of the art

Currently, for smelting ice on OL wires, exclusively stationary current sources are used [1], which are connected to long sections of OHL that are prone to ice formation. However, the practice of operating a 110-220 kV overhead line showed that only 7 to 30% of the length of the heated wire during melting is really covered with ice. Electricity losses are significant. Using a mobile installation for melting ice allows you to travel to those sections of overhead lines where icing of wires is detected.

SUMMARY OF THE INVENTION

Proposed as an invention, a mobile current generator for melting ice is shown in general form in Figure 1, where:

1 - Car.

2 - Power rectifier converter.

3 - Two diesel generators ADV320 of 320 kW.

4 - Lift APT-50.

The presented version of the power secondary converter compares favorably with the classical circuit with a controlled thyristor rectifier. The main advantages of this solution are the following aspects:

- Lack of power transformer;

- Simplified circuitry and manufacturing;

- Increased reliability;

- Decrease in losses;

- Work of diesel generators in the soft mode of a direct current source;

- Ease of implementation of the control algorithm.

The circuit diagram of the secondary Converter shown in figure 2, where:

1 - A, B, C phase voltage 400 V;

2 - L1 inductance of the input filter;

3 - C1 input filter capacity;

4 - K1 power semiconductor converter

5 - Cx. Control Converter control circuit;

6 - C2 - output filter capacity;

7 - Rn Load.

As a result of model studies and preliminary calculations, an installation option has been formed that has unique properties and has no analogues in world practice.

The use of two diesel generators and the rejection of the use of a traditional power transformer in melting systems makes it possible to simplify the control of a power plant, increase its reliability and significantly reduce weight and size characteristics, as well as its cost.

Given that the mobile current generator for melting ice includes a lifting mechanism, for example APT-50, which, in the end, gives it the following differences:

1. Installation for smelting ice provides independent movement to the place of production of smelting.

2. The proposed solution provides quick assembly of the circuit, and after melting ice, it restores the normal operation of the network.

3. The selected layout includes a lifting mechanism, which provides quick switching of the supply wires to the overhead lines and significantly expands the functionality of the installation.

4. Two diesel-generators provide redundancy of the main component of the system, while maintaining the possibility of melting with increasing process time.

5. The deployment time of one set, from the moment of arrival at the place - 20-30 minutes. (with a manipulator).

6. Installation for melting ice provides melting at a distance of at least two spans.

7. Provides operational melting on grounded lightning protection cables without dismantling the suspension.

8. The life of the system is at least 8 years.

9. The operating modes of the device - semi-automatic - under the control of the operator.

A mobile current generator for melting ice on wires of overhead power lines differs from the known circuit solutions [2] for stabilizing the load current as follows:

- two diesel electric generators were used as a source of electrical energy, the rectified voltage of which is connected either in series or in parallel, depending on the current value required for melting, providing an increase in the output voltage at high circuit resistances.

- by means of a semiconductor converter providing a current source mode, a soft mode of operation of diesel generators is achieved.

- the current source mode of the semiconductor converter ensures the constancy of a given current of melting ice, regardless of the electrical resistance of the wire circuits and ground circuits.

- its circuit design provides ice melting on phase wires and a lightning protection cable for overhead lines, including the performance of a lightning protection cable with grounding on each support, for a length of up to two overhead spans.

Industrial applicability

The use of the invention in the cleaning of overhead lines of existing power supply systems, electrical substations, power lines and other power facilities, especially for 110 and 220 kV networks, will eliminate the human factor in the causes of accidents, increase their operational reliability and safety.

A mobile current generator for melting ice allows not only to significantly reduce the cost of operating the overhead line, but also to provide quick cleaning of the overhead line from ice.

References:

1. METHODOLOGICAL INSTRUCTIONS FOR GLASS MELTING BY AC. Part 1. RD 34.20.511 (MU 34-70-027-82). Developed by the All-Union Scientific Research Institute of Electric Power Industry (VNIIE) and the Lviv Order of Lenin Polytechnic Institute. Approved by the Main Technical Department for Power Systems Operation Deputy Chief K.M. Antipov. Date of introduction: 01-01-1983 to 31-12-1999

2. Rectifiers with thyristor voltage regulator. A. Fedyukov. fedjukov@mail.ru http://www.fedjukov.narod.ru/. Aug 22 2006.

Claims (1)

A mobile current generator for melting ice on wires of overhead power transmission lines (OHL), containing an electric energy source in the form of two diesel electric alternating voltage generators, an alternating voltage rectifier, conductors with terminals for connecting it to OHL wires and busbars for connecting OHL wires on the span between supports according to the ice melting scheme, characterized in that by means of a semiconductor converter with a control circuit providing a current source mode, soft operation of diesel electric generators is ensured, that the semiconductor converter ensures the constancy of a given current of melting ice irrespective of the electrical resistance of the wire circuits and ground circuits, that its circuit solution provides melting of ice on the length of up to two overhead spans on phase wires and a lightning protection cable for overhead lines, including including when performing a lightning protection cable with grounding on each support.

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