Single-stranded conductors are often used for 230 kV or higher system overhead transmission lines; above this voltage, multi-stranded systems such as two, three, or four strands with bundle conductor spacers are required. Single-stranded conductors can be from 3 mm to 12 mm in diameter, while multistranded conductors are usually from 6 mm to 20 mm in diameter.
The choice of conductor size depends on several factors such as line length, loading, environmental conditions, and power distribution density. Longer lines require larger conductors to avoid electrical field concentrations that could lead to breakdown. Larger cross sections are also necessary to carry more current without overheating. Environmentally sensitive areas such as parks or forests may only allow certain sizes of conductors to be used. Power distribution density determines the number of conductors required for a given distance, since each conductor must be able to support its share of the load.
For example, if it is known that a line will carry 15 amperes between two points 10 miles apart, then it can be calculated that this line needs to be at least 3/0.15 = 20 mm in diameter. If the line is actually located 20 miles away from where it was estimated to be, then it becomes clear that this size conductor cannot be used because it would be too small to carry the current.
Overhead Transmission Conductor, 132 KV ACSR, Aluminium Conductor Steel Reinforced.
|Rated Voltage:||132kV||Aluminium And Steel|
|Application:||Overhead Transmission Line||Circular|
|Type:||High Voltage||10-800 Sq Mm|
|High Light:||transmission conductor , overhead line Conductor|
Bundled conductors are used for power transmission over 400 kV. Bundled Conductors Have Many Advantages: Bundled conductors are generally used to decrease corona loss and radio interference. They also provide an effective method of control since if one section of cable fails, the entire length remains in service.
The main advantage of using bundled conductors is that the overall voltage drop across them is less due to lower resistance per unit length. This means that a given amount of current can be transmitted through the line. Transmitting at higher currents is important because it leads to reduced wire weight and size requirements. It has been estimated that if all of Europe's electricity were transmitted over single wires, they would need to be more than 200 km long! The actual distance between poles varies with height but usually ranges from 50-100 km.
At very high voltages, such as those found on power lines, electrical energy cannot travel along a single conductor. It must be transmitted in stages from one end of the line to the other. A single conductor cannot carry both a positive charge and a negative charge at the same time, nor can it transmit radio waves. To overcome these problems, two parallel conductors are used instead. These are called "pairs" or "groups" of conductors.
Bundled conductors are used in Extra High Voltage (EHV) transmission because the corona effect is prominent at higher levels. This minimizes corona discharge loss and interferes with surrounding communication connections. EHV transmission lines usually have 100 or 200 kv insulation between them.
The advantage of using bundled conductors is that they can be formed into large numbers of small sections, which makes them suitable for high voltage applications. Also, their effective cross-section area is larger than that of solid conductors of equal diameter. This means that more current can be carried by the cable if it is not overloaded. Finally, bundled conductors are less likely to fail by thermal stress as they operate at lower temperatures than solid conductors of equal diameter.
Bundled conductors are used in power transmission cables because they offer some protection against short circuits by allowing an arc to jump from one conductor within the bundle to another. This protects other cables or parts of the circuit from being damaged by the current flowing through the shorted section of cable.
Solid conductors are used in low voltage distribution networks because they are cheaper and easier to install than bundled conductors. However, they cannot be used for transmission lines because they would be unable to carry the required amount of current.
A wire is often defined as a single solid metal strand, whereas a cable is defined as numerous strands or bundles of wire. In both circumstances, they act as electrical signal conductors. They are available in a variety of shapes and sizes for power transmission and telecommunication. Cable is used to connect electrical components together while wire is used at lower voltages where the risk of electrical shock is greater.
Cables consist of multiple insulated wires or fiber-optic cables surrounded by a protective jacket. Cables can be rigid, such as steel cable, or flexible, such as copper wire rope. The term "cord" is used for both types of cable unless otherwise specified. A group of individual wires or fibers that are bound together with a plastic braid is called a "bundle". The word "trunk" is also used for this type of cable. Cord is used to connect electrical equipment together; wire is used at lower voltages where the risk of electric shock is greater.
Wire comes in several forms: straight, bent, taped, and woven. Straight wire is most commonly used for wiring buildings because it can be easily inserted into holes and concealed under floors and ceilings. It can also be cut to length without being removed from its packaging. Bent wire is used when a piece of wire must make a sharp turn. For example, it is necessary to bend a cable so that it will fit under a dashboard or cabinet door.