High voltage reduces current and losses over long distances.
Overhead lines and cables carry bulk power at high voltage (110–765 kV) to cut I²R losses. Corona, sag, clearances and right of way affect design. Long lines show Ferranti effect and need compensation.
Doubling voltage quarters the current for the same power.
High voltage transmission reduces current for the same power, which cuts resistive losses and lets long lines be built economically.
High voltage reduces current and losses over long distances.
High voltage transmission reduces current for the same power, which cuts resistive losses and lets long lines be built economically.
For a given power, current falls as voltage rises, and losses depend on the square of current, so losses fall rapidly.
Insulation, corona discharge and equipment costs rise, so the voltage is chosen to balance losses against these costs.
Typical applications include choosing a transmission voltage for a 100 km line carrying 100 MW, explaining why power lines use high voltage instead of thick cables and estimating the losses of a rural grid extension.
Study "Power generation methods" first (topic 66 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Surge impedance loading. Underground cables have high capacitance. Thermal rating.
Doubling voltage quarters the current for the same power.
The next topic is "Per-unit system", which builds directly on this one.
It is classed as Intermediate in Electrical Engineering (topic 67 of 106). It is an intermediate topic. Work through the beginner topics in Electrical Engineering first.
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