A high-voltage cable (HV Cable) is a type of cable used for high-voltage electric power transmission. Insulation and a conductor are components of a cable. Cables are thought to be completely insulated. This indicates that they have a fully rated insulation system, which will include metallic shield, insulation, and semi-conductor layers. An overhead line, on the other hand, might have insulation but is only partially qualified for operational voltage (EG: tree wire). Numerous instruments, ignition systems, and alternating current (AC) and direct current (DC) power transmission systems use high-voltage cables of various types. The cable's insulation must not deteriorate in any application because of high-voltage stress, ozone created by electric discharges in the air, or tracking.

The cable system must contain and manage leakage current as well as prevent the high-voltage conductor from coming into contact with other things or people. To stop the breakdown of the insulation, cable couplings and terminals must be made to control the high-voltage stress.

High-Voltage Cables can be cut to lengths ranging from a few feet to hundreds of feet, with shorter cables used in equipment and larger cables run within buildings, buried in an industrial complex, or used for power distribution. The longest cut lengths of cable will generally be submarine cables under the ocean for electricity transmission

Depending on the length of the circuit and whether a semiconducting jacket is used on direct buried wires, splices in the middle of the cable may also be grounded.

Any voltage greater than 1000 volts is considered a high voltage. Medium voltage cables are typically those between 2 and 33 kV, and high voltage cables are those over 50 kV.

The conductor, the conductor shield, the insulation, the insulation shield, the metallic shield, and the jacket are the only components of modern HV cables. Ripcords, armour wires, and water-blocking tapes are examples of additional layers. Wires made of copper or aluminium carry the current (For a detailed discussion on copper cables, see main article: Copper conductor.) With a few uncommon exceptions, the insulation, insulation shield, and conductor shield are typically made of polymers.

Design of HV Cable

Two qualities emerged as being crucial throughout the development of high voltage insulation, which took around fifty years. The introduction of the semi-conductive layers comes first. These layers must be completely smooth, without even the slightest protrusions of a few micrometers. Furthermore, there must be complete fusion between the insulation and these layers; any fission, air-pocket, or other imperfection, even by a few micrometers, is harmful to the cable. Second, there must be no inclusions, cavities, or other problems of a similar size in the insulation. Any such flaw reduces the cable's voltage life, which is meant to be in the range of 30 years or more.

As a result of collaboration between cable manufacturers and material producers, XLPE grades with exacting standards already exist. The majority of XLPE-compound manufacturers specify an "extremely clean" grade with guaranteed foreign particle quantity and size. It is necessary to pack and unload the raw materials into the cable-making machines in a clean-room setting. Cable-making installations for producing pure and defect-free insulation have been made possible by the introduction of extruders for plastic extrusion and cross-linking.

High Voltage Cable in Brief;

Knowing the actual and physical power of high voltage makes it simple to remember how it operates and is built. For the transmission of electric power, a particular high-voltage power cable is needed because individual conductors carry high voltage. For a standard high-voltage power cable, the following is necessary:

• An operator, or conductor,

• Insulation that can be applied both above and below water

• Ensuring that the high voltage effect is controlled and doesn't cause the insulation to fail in the cable and joints

Structure or appearance of HV cables

The structure of a high-voltage power cable includes one or more conductors, suitable insulation, and a protective jacket. The number of layers in the insulation jacket of the cables might vary depending on the voltage power level in order to control the electric field in the conductor.

Conductors that operate at voltages higher than 2,000 volts frequently employ high-voltage power cables. With this amount in mind, each insulator conductor will have a conductive shield that aids in distributing electrical stress. Because Martin Hochstadter patented this method in 1916, this shield is occasionally referred to as the Hochstadter shield.

• "Stress relief cones" are mounted at the ends of shields.

• 100,000 V power distribution cables have good oil insulation.

(This view will change according to HV Cable Suppliers.)

Types of High Voltage Cable

High voltage cables come in a variety of types to suit various uses. Some are essential for the operation of instruments, the transmission of AC and DC power, and ignition systems. A high voltage power cable system is intended to prevent any contact.

• HVDC

Similar to the AC cable, a high-voltage cable for high-voltage direct current (HVDC) transmission has the same design. The test requirements are different from the physics. The semiconducting layers (2) and (4) must be as smooth as possible in this situation. The insulation must still be kept clean.

Since AC can no longer be used at distances of more than about 100 km, many HVDC cables are used for DC undersea connections. The North Sea Link cable, which runs 720 kilometers (450 miles) between Norway and the UK as of 2021, is the longest submarine cable in existence.

Features of HV cables

• High voltage power cables have a few unique characteristics and are designed to function with particular switching and distribution panels.

• They make it possible to manually or remotely switch and control control rooms for the testing of individual supply systems.

• High voltage power cable substations have the ability to reduce the voltage in an effort to distribute it to nearby locations.

• The semiconducting layers should be a few micrometers thick and smooth. Any fission or gap between the layers' fusion and insulation can be extremely hazardous.

   

Maintenance Tips from The Cable Manufacturer

It is essential to make sure the high-voltage power cable you install for the underground electric transmission system is of the highest caliber.

Make sure the high-voltage power cord you choose is strong enough to resist harsh environments. The materials used for these cables should be of the highest quality and incorporate a variety of energy-efficient technologies because they deal with high voltage and have the potential to deliver severe electric shocks.

Keep track of every cable you use, especially if the environment is industrial. If you keep a record of all your wires and cables, you should have a good idea of when the next maintenance or repair check is due.

High Voltage Cable Manufacturers in Australia: Znergy Cables

Znergy Cable, the leading high-voltage cable producer in Australia, has a cutting-edge high-voltage cable plant that uses upgraded technology. Znergy Cable manufactures high-voltage cables in accordance with AS1802 Cable specifications and standards. Additionally, our knowledgeable research and development staff can help with manufacturing to an international standard for safety purposes.

 

Also Read: What is High Voltage Cable and Its Used?