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Why overhead transmission lines would be more economical than underground transmission lines in high voltage transmission?
Wiki User
∙ 15y ago
Overhead wires do not require insulation, and it is easier to plant poles than dig miles of trenches.
Wiki User
∙ 15y ago
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Why we can't send current or voltage without transmission line?
Well, there is no way of doing it without an overhead or underground transmission line.
Why overhead lines are far cheaper than underground cables for long distances and less economical for short distances?
First of all, the overhead lines are cheaper because they are bare, while underground cables are armoured and insulated, hence explaining the higher price. Overhead cables come of course with accessories like poles and insulators (mostly porcelain). For shorter distance, underground cables are preferred as the cost of pole erection does not exist.It's also worth pointing out that the cost of excavating a trench is more expensive than erecting an overhead line, and this cost escalates dramatically with higher voltage systems. For example, a 132-kV double-circuit underground line is between 5 and 8 times the cost of an overhead tower line, whereas an 11-kV single-circuit underground line is up to twice the cost of a wooden-pole overhead line.
How is electrical transmission loss?
Tramsission losses are due to the inherent resistivity of the transmission medium (the wire in overhead and underground transmission lines). All substances have a specific resistance. As current is pushed through that substance, a voltage drop across that resistance will result that follows ohm's law: V = I * R. Power is equivalent to P = V * I, thus P = I^2 * R.
Why are high voltage poles are kept above ground?
A couple of reasons I can think of include: High voltage overhead cable is much cheaper than underground cable Easier to reconductor (upgrade current carrying capacity) Easier to find faults
Are distribution feeders overhead or underground?
High voltage above 25 kV are usually overhead feeders. Below 25 kV can be both overhead and underground. The lower voltage feeders are brought into a transformer vault that is usually located in the basement or first floor of a many storied building.
What is the induced voltage on a deenergized ungrounded circuit 60 feet from a 230000 volt circuit?
This question has not enough information for an answer. Is the 230 kV line overhead or underground? The voltage induced in a passive wire also depends on the amount of current in the high-power line.
What are the two basic categories of transmission?
The two basic categories of transmission are:High voltage transmission andLow voltage transmission.
What is the voltage on a railway?
Overhead wires on the railways are 250v
How capacitance effects are taken into account in transmission lines?
Natural capacitance exists between conductors at different potentials, including between those conductors and earth (ground). The value of such capacitance is significantly higher with underground cables than with overhead lines, due to the close proximity of the individual conductors in an underground cable. Capacitance results in line losses in both a.c. overhead and underground systems, due to the corresponding capacitive reactance (opposition to a.c.). In the case of long, high-voltage, underground or under-sea cables, the capacitance losses can be so high that d.c. transmission is used instead of a.c. (d.c. eliminates capacitive line losses). In addition to the line losses, the electric fields resulting from the capacitance can lead to insulation breakdown -making it essential that 'sharp corners', etc., are avoided in their design and construction. One of the reasons that high-voltage overhead conductors are 'bundled' (i.e. more than one conductor per line) is to reduce the stress on individual line conductors that would otherwise occur due to their relatively small diameters.
What is the largest transmission voltage for WECC?
The highest transmission voltage in the Western Interconnection (2011) is 500kv.
Why transmitting of power at high voltage is economical?
For a given load, the higher the supply voltage, the lower the resulting load current. So, using high-voltages in transmission systems (1) avoid enormous voltage drops along the line, (2) enable cables of realistic cross-sectional area and weight to be used, and (3) minimise line losses. So, high-voltage transmission requires less copper and avoid line losses -resulting in lower costs.
Where is the highest transmission voltage in India?
the highest transmission volatage in India is 765kV ac. The highest voltage in the case of DC transmission is +/- 600 kV.
