Electric power transmission is the bulk movement of electrical energy from a generating site, such as a power plant i.e wind,geothermal,hydro.., over long distances to an electrical substation. The interconnected lines which facilitate this movement are known as a transmission network.
Svalbard Cables portfolio for an efficient power transmission and installations comprises high-voltage transmission solutions, high-voltage switching products and systems as well as power and distribution transformers.
During the construction of generating stations a number of factors are to be considered from the economic point of view. These all factors may not be easily available at load center; hence generating stations are not normally situated very nearer to load center.
Load center is the place which consumes maximum power. Hence there must be some means by which we can transmit the generated power
to the load center.
Electrical transmission system is the means of transmitting power from generating station to different load centers.
During the planning of construction of generating stations the following factors are to be considered for the economical generation of electrical power.
Easy availability of water for thermal power generating station.
Easy availability of land for construction of power station including its staff township.
For hydro power station there must be a dam on river. So proper place on the river must be chosen in such a way that the construction of the dam can be done in most optimum way.
For thermal power station easy availability of fuel is one of the most important factors to be considered.
Better communication for goods as well as employees of the power station also to be kept into consideration.
For transporting very large spare parts of turbines, alternators, etc., there must be wide roadways, train communication, and deep and wide river must pass away nearby the power station.
For nuclear power plant, it must be situated in such a distance from common location so that there may not be any effect from nuclear reaction the heath of common people.
The power generated at a generating station is in low voltage level as low voltage power generation has some economical values.
Low voltage power generation is more economical than high voltage power generation. At low voltage level, both weight and insulation are less in the alternator; this directly reduces the cost and size of an alternator. But this low voltage level power cannot be transmitted directly to the consumer end as because this low voltage power transmission is not at all economical.
Hence although low voltage power generation is economical but low voltage electrical power transmission is not economical. Electrical power is directly proportional to the product of electrical current and voltage of the system. So for transmitting certain electrical power from one place to another, if the voltage of the power is increased then associated current of this power reduces.
Reduced current means less I2R loss in the system, less cross-sectional area of the conductor means less capital involvement and decreased current causes improvement in voltage regulation of power transmission system and improved voltage regulation indicates quality power.
Because of these three reasons electrical power mainly transmitted at high voltage level.
Again at the distribution end for efficient distribution of the transmitted power, it is stepped down to it's desired low voltage level.
So it can be concluded that first the electrical power is generated at low voltage level then it is stepped up to high voltage for efficient transmission of electrical energy. Lastly, for the distribution of electrical energy or power to different consumers, it is stepped down to the desired low voltage level.
Fundamentally there are two systems by which electrical energy can be transmitted.
High voltage DC electrical transmission system.
High AC electrical transmission system.