Low voltage and medium voltage power cables (often abbreviated as LV and MV) are the two most common types of power cables typically used to power wind turbines and wind farms. Let's describe the differences between their applications.
How are LV cables used in wind farms?
Low voltage cables are cables up to 1000 V. In wind turbines, low-voltage cables are used in a limited range of applications. In particular, low-voltage cables are used:
For connecting generators to transformers
for converting power from the wind turbine to the generator (both LV and MV cables are used for this purpose)
For lighting in the tower and throughout the wind farm
In standard size turbine generators (typical voltages around 700 – 1000 volts)
How are MV cables used in wind farms?
Medium voltage is a cable with a voltage higher than 1000v. In wind farms, medium voltage cables can be used as a compromise between low and high-voltage solutions. Medium voltage cables are used for budgetary reasons, as high voltage cables are expensive, and not all wind farms are allowed to rely exclusively on high voltage wires and cables. Medium-voltage cable systems are also sometimes more beneficial than low-voltage cable systems because they are compact.
Depending on the situation, all types of medium-voltage cables can be used to power wind farms. This includes 2.4 KV, 5 KV/8 KV, 15 KV, and 25 KV/KV. However, typical voltages for MV cables in the U.S. are 10 KV to 35 KV. If you are in any doubt, use the standard MV cable voltage for your country/region.
Medium voltage MV cables for wind farms are used for:
Underground and overhead power lines (underground is the most common of the two)
Bringing power from the nacelle to the bottom of the tower
Inside large turbine generators (3kV voltage generators)
In summary, medium voltage cables are by far the most common cables used in wind farms, while low voltage cables are used for some limited applications. If you would like to learn more about the cables used in wind turbines (not just power cables), please read the blog dedicated to this subject. This blog focuses on the differences between power cables used in offshore wind farms and onshore wind farms. This information is essential for choosing a cable for a specific voltage for a wind farm.
Comments