CN104716613B - De-icing method based on 500kV transmission line of electricity - Google Patents

Abstract

The invention discloses a kind of de-icing method based on 500kV transmission line of electricity, comprise the steps: (1), record strain section and conductor spacer quantity, optimize conductor spacer and realize sub-conductor all insulation；(2), test platform is built；(3), carry out A phase conductor ice-melt test, the high-voltage output end of movable DC ice melting device and earth terminal are connected respectively one or two in A phase quadripartion sub-conductor；(4), call through test ring current carries out the ice-melt test of A phase quadripartion sub-conductor；(5) open test power supply, connects remaining one by the high-voltage output end of movable DC ice melting device, and earth terminal connects any two in another root remaining or step 3, repeats step 4, until A phase conductor icing melts away completely；(6) repeat step 3～5, carry out B phase conductor ice-melt test；(7), repeat step 3～5, carry out C phase conductor ice-melt test.The present invention can meet the demand of 500kV transmission line de-icing capacity.

Description

Ice melting method based on 500kV transmission line

technical field

The invention belongs to the technical field of electrical engineering, and in particular relates to a method for melting ice based on a 500kV transmission line.

Background technique

With the sharp increase in the demand for electricity in modern society, the power grid transmission adopts the long-distance and large-capacity transmission method. Hunan has formed a backbone transmission network with a voltage level of 500kV, and the distance between adjacent towers is very large; on the other hand, my country in 2007 From the end of 2008 to the beginning of 2008, many provinces and cities in the south of the country caused huge losses to people's lives and national property due to line disconnection and tower collapse accidents caused by rainy, snowy and freezing weather. The increase in ice capacity will inevitably increase the weight and volume of the ice-melting device, which is not only expensive, but also not easy to carry on site. The limitation of the special and complex terrain on site also affects its ability to resist ice disasters to a certain extent.

At present, my country's AC 500kV transmission lines generally use four-split sub-conductors, and a four-split spacer bar must be installed every 40 to 100 meters between the four-split sub-conductors to keep the distance between the four sub-conductors constant and suppress vibration. At present, domestic The four-split spacer is made of metal material, and it is difficult to maintain the insulation between the four sub-conductors in the tension section.

Contents of the invention

The object of the present invention is to provide a kind of can reduce the capacity of ice-melting device on the basis of full insulation of four-splitting sub-conductors, realize phase-by-phase melting of ice for three-phase transmission lines, realize miniaturization and portable design of ice-melting device, make melting The ice device is more flexibly applied to the ice-melting method based on 500kV transmission lines in ultra-high voltage lines with large spans.

This deicing method based on the 500kV transmission line provided by the present invention comprises the following steps:

(1) Record the number of tension sections of each phase conductor of the 500kV four-split transmission line to be transformed, the number of spans in each stretch section, and the number of four-split spacers between the four-split sub-conductors in each span. Equipped with four-split fully insulated spacers equal to the number of recorded four-split spacers to realize full insulation of four-split sub-conductors of 500kV four-split transmission lines;

(2) Build a test platform, which has a voltage regulator, a power transformer, a mobile DC ice-melting device, a wine glass-shaped iron tower and four-split conductors of a 500kV four-split transmission line;

(3) Carry out the ice-melting test of the A-phase wire of the 500kV four-split transmission line, connect the circuit of the test platform, and connect its high-voltage output end to the A-phase four-split sub-wire according to the capacity requirements of the mobile DC ice-melting device One or two, and the corresponding ground terminal is connected to the other one or two of the A-phase four-split sub-conductor;

(4) Connect the loop power supply of the test platform, and increase the voltage slowly and uniformly through the voltage regulator until the output voltage of the power transformer reaches the rated voltage of the mobile DC ice melting device. Keep the voltage constant. Carry out the ice-melting test of the A-phase four-split wire, and record the ambient temperature and ice-melting time;

(5) When there is a four-split wire in phase A of step 3 that has not been subjected to the ice-melting test, disconnect the loop power supply of the test platform, and connect the high-voltage output terminal or ground terminal of the mobile DC ice-melting device to the four-split wire of phase A. For one of the wires that has not been subjected to the ice-melting test, connect its corresponding ground terminal or high-voltage output terminal to the other of the A-phase four-split sub-conductors that have not been subjected to the ice-melting test or to the two wires that have undergone the ice-melting test. Repeat step 4 until the ice on the phase A conductor is completely melted, and disconnect the loop power supply of the test platform;

(6) Carry out the ice-melting test of the B-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice on the B-phase conductor is completely melted, and disconnect the loop power supply of the test platform;

(7) Carry out the ice-melting test of the C-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice of the C-phase conductor is completely melted, disconnect the loop power supply of the test platform, and complete the 500kV Four-split transmission line A, B, C three-phase ice melting.

The four-split fully insulated spacers in step 1 are made of epoxy resin insulating material.

Compared with the prior art, the present invention has the following advantages:

1. Create conditions for 500kV ultra-high voltage fully insulated four-split sub-conductor DC ice melting;

2. The present invention can realize the miniaturized design of the capacity and volume of the mobile direct current ice-melting device, which is suitable for complex mountainous terrain;

3. Reduce the capacity of the mobile DC ice melting device to ensure the safety of the test. In the 500kV power transmission system, the ice melting current of the mobile DC ice melting device can be reduced to a minimum of 1/4 of the traditional equipment;

4. The method is simple and easy, and does not require large-scale modification of the line;

5. The present invention is suitable to be extended to the DC deicing of UHV multi-splitting conductors.

detailed description

Example 1——Two sub-conductors melt ice at the same time:

This ice-melting method based on 500kV transmission line of the present invention comprises the following steps:

(1) Record the number of tension sections of each phase conductor of the 500kV four-split transmission line to be transformed, the number of spans in each stretch section, and the number of four-split spacers between the four-split sub-conductors in each span. Equipped with four-split fully insulated spacers equal to the number of recorded four-split spacers to realize full insulation of four-split sub-conductors of 500kV four-split transmission lines;

(2) Build a test platform, which has a voltage regulator, a power transformer, a mobile DC ice-melting device, a wine glass-shaped iron tower and four-split conductors of a 500kV four-split transmission line;

(3) Carry out the ice-melting test of the A-phase wire of the 500kV four-split transmission line, connect the circuit of the test platform, and connect its high-voltage output end to the A-phase four-split sub-wire according to the capacity requirements of the mobile DC ice-melting device For the first sub-conductor, the corresponding ground terminal is connected to the second sub-conductor of the four-split sub-conductor of phase A;

(4) Connect the loop power supply of the test platform, and increase the voltage slowly and uniformly through the voltage regulator until the output voltage of the power transformer reaches the rated voltage of the mobile DC ice melting device. Keep the voltage constant. Carry out the ice-melting test of the A-phase four-split wire, and record the ambient temperature and ice-melting time;

(5) Disconnect the loop power supply of the test platform, connect the high-voltage output terminal or ground terminal of the mobile DC ice-melting device to the third sub-conductor of the A-phase four-split sub-conductor, and connect its corresponding ground terminal or high-voltage output terminal to The fourth sub-conductor of the phase A four-split sub-conductor. Repeat step 4 until the ice on the phase A conductor is completely melted, and disconnect the loop power supply of the test platform;

(6) Carry out the ice-melting test of the B-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice on the B-phase conductor is completely melted, and disconnect the loop power supply of the test platform;

(7) Carry out the ice-melting test of the C-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice of the C-phase conductor is completely melted, disconnect the loop power supply of the test platform, and complete the 500kV Four-split transmission line A, B, C three-phase ice melting.

The four-split fully insulated spacers in step 1 of the present invention are made of epoxy resin insulating material.

Example 2—Three sub-conductors melt ice at the same time:

This ice-melting method based on 500kV transmission line of the present invention comprises the following steps:

(1) Record the number of tension sections of each phase conductor of the 500kV four-split transmission line to be transformed, the number of spans in each stretch section, and the number of four-split spacers between the four-split sub-conductors in each span. Equipped with four-split fully insulated spacers equal to the number of recorded four-split spacers to realize full insulation of four-split sub-conductors of 500kV four-split transmission lines;

(2) Build a test platform, which has a voltage regulator, a power transformer, a mobile DC ice-melting device, a wine glass-shaped iron tower and four-split conductors of a 500kV four-split transmission line;

(3) Carry out the ice-melting test of the A-phase wire of the 500kV four-split transmission line, connect the circuit of the test platform, and connect its high-voltage output end to the A-phase four-split sub-wire according to the capacity requirements of the mobile DC ice-melting device The first and second sub-conductors, the corresponding ground terminal is connected to the third sub-conductor of the four-split sub-conductor of phase A;

(4) Connect the loop power supply of the test platform, and increase the voltage slowly and uniformly through the voltage regulator until the output voltage of the power transformer reaches the rated voltage of the mobile DC ice melting device. Keep the voltage constant. Carry out the ice-melting test of the A-phase four-split wire, and record the ambient temperature and ice-melting time;

(5) Disconnect the loop power supply of the test platform, connect the high-voltage output terminal or ground terminal of the mobile DC ice-melting device to the fourth sub-conductor of the A-phase four-split sub-conductor, and connect its corresponding ground terminal or high-voltage output terminal to The first and second sub-conductors of the four-split sub-conductor of phase A. Repeat step 4 until the ice on the phase A conductor is completely melted, and disconnect the loop power supply of the test platform;

(6) Carry out the ice-melting test of the B-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice on the B-phase conductor is completely melted, and disconnect the loop power supply of the test platform;

(7) Carry out the ice-melting test of the C-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice of the C-phase conductor is completely melted, disconnect the loop power supply of the test platform, and complete the 500kV Four-split transmission line A, B, C three-phase ice melting.

The four-split fully insulated spacers in step 1 of the present invention are made of epoxy resin insulating material.

Embodiment 3——Four sub-conductors melt ice at the same time:

This ice-melting method based on 500kV transmission line of the present invention comprises the following steps:

(1) Record the number of tension sections of each phase conductor of the 500kV four-split transmission line to be transformed, the number of spans in each stretch section, and the number of four-split spacers between the four-split sub-conductors in each span. Equipped with four-split fully insulated spacers equal to the number of recorded four-split spacers to realize full insulation of four-split sub-conductors of 500kV four-split transmission lines;

(2) Build a test platform, which has a voltage regulator, a power transformer, a mobile DC ice-melting device, a wine glass-shaped iron tower and four-split conductors of a 500kV four-split transmission line;

(3) Carry out the ice-melting test of the A-phase wire of the 500kV four-split transmission line, connect the circuit of the test platform, and connect its high-voltage output end to the A-phase four-split sub-wire according to the capacity requirements of the mobile DC ice-melting device For the first and second sub-conductors, the corresponding grounding terminals are connected to the third and fourth sub-conductors of the four-split sub-conductors of phase A;

(4) Connect the loop power supply of the test platform, and increase the voltage slowly and uniformly through the voltage regulator until the output voltage of the power transformer reaches the rated voltage of the mobile DC ice melting device. Keep the voltage constant. Carry out the ice-melting test of the A-phase four-split wire, record the ambient temperature and the ice-melting time until the ice on the A-phase wire is completely melted, and disconnect the loop power supply of the test platform;

(5) Carry out the ice-melting test of the B-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice on the B-phase conductor is completely melted, and disconnect the loop power supply of the test platform;

(6) Carry out the ice-melting test of the C-phase wire of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice of the C-phase wire is completely melted, disconnect the loop power supply of the test platform, and complete the 500kV Four-split transmission line A, B, C three-phase ice melting.

The four-split fully insulated spacers in step 1 of the present invention are made of epoxy resin insulating material.

After long-term test records, in the above embodiments, the ice-melting current can be reduced to 1/4 of the ice-melting current of the traditional device.

Claims (2)

1. A method for melting ice based on 500kV transmission line, comprising the steps: (1) Record the number of tension sections of each phase conductor of the 500kV four-split transmission line to be transformed, the number of spans in each stretch section, and the number of four-split spacers between the four-split sub-conductors in each span; Equipped with four-split fully insulated spacers equal to the number of recorded four-split spacers to realize full insulation of four-split sub-conductors of 500kV four-split transmission lines; (2) Build a test platform, which has a voltage regulator, a power transformer, a mobile DC ice-melting device, a wine glass-shaped iron tower and four-split conductors of a 500kV four-split transmission line; (3) Carry out the ice-melting test of the A-phase wire of the 500kV four-split transmission line, connect the circuit of the test platform, and connect its high-voltage output end to the A-phase four-split sub-wire according to the capacity requirements of the mobile DC ice-melting device One or two, and the corresponding ground terminal is connected to the other one or two of the A-phase four-split sub-conductor; (4) Connect the loop power supply of the test platform, and increase the voltage slowly and uniformly through the voltage regulator until the output voltage of the power transformer reaches the rated voltage of the mobile DC ice-melting device. The ice melting test, record the ambient temperature and ice melting time; (5) When there is a four-split wire in phase A of step 3 that has not been subjected to the ice-melting test, disconnect the loop power supply of the test platform, and connect the high-voltage output terminal or ground terminal of the mobile DC ice-melting device to the four-split wire of phase A. One of the wires that has not been subjected to the ice-melting test, connect its corresponding ground terminal or high-voltage output terminal to the other wire that has not been subjected to the ice-melting test or the two wires that have been subjected to the ice-melting test, and repeat Step 4, until the ice on the A-phase conductor is completely melted, disconnect the loop power supply of the test platform; (6) Carry out the ice-melting test of the B-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice on the B-phase conductor is completely melted, and disconnect the loop power supply of the test platform; (7) Carry out the ice-melting test of the C-phase conductor of the 500kV four-split transmission line, change the loop wiring of the test platform and repeat steps 3 to 5 until the ice of the C-phase conductor is completely melted, disconnect the loop power supply of the test platform, and complete the 500kV Four-split transmission line A, B, C three-phase ice melting. 2. The ice-melting method based on 500kV transmission line according to claim 1, characterized in that: in the step 1, the four-split fully insulated spacers are made of epoxy resin insulating material.