Line Differential Protection in three-terminal…

Renewable energy plants are usually connected to an already existing transmission line in what is usually called a T-connection. One of the particularities of this type of connection is that, in the case of having a line differential function (87L) enabled, the protection relays must support its three ends and be able to form a ring between them.
Read more

Power Quality Solutions for Grid Connection…

Grid Codes include a series of requirements associated with voltage and reactive power control which must be fulfilled, for the most part, at the generation unit level. In the case of renewable plants, the usual problems are related to the inability to comply with reactive power delivery and voltage control at the point of connection and to a possible excess of harmonic distortion. As detailed below, different solutions are available to solve these problems.
Read more

Distance protection schemes with teleprotection…

The power generated in renewable plants is evacuated via transmission lines that must be protected against any electrical fault that may originate in the system. Traditionally, protection schemes based on Directional Overcurrent (50/51 with 67), Distance (21) or Differential (87) have been used.
Read more

High Voltage harmonic measurement with…

Power quality monitoring, and in particular harmonic measurement, is becoming more and more critical in the power system. This is going around for many years, but recently it has also arrived to High Voltage systems. With the increased presence of Renewable Energies, in particular solar and wind power, and their use of inverter-based technologies, harmonic presence in High Voltage substations, particularly those connected to RE plants, has become an issue that needs to be addressed.
Read more

Preliminary PQ Measurement Importance and its…

According to global energy trends, sources of both low and high order harmonics are increasing continuously, not only in distribution grids but also in transmission levels (wind farms, photovoltaic parks, HVDC links, and FACTS devices).
Read more

NTS 2.1. and 2.0. Are you aware of the…

As you may know, the certification procedure for renewable plants in Spain is mandatory for connecting generation plants to the grid and it is in constant evolution.  In this article we explain the most important changes that have been made in the new technical standard (NTS) and how they can affect the grid connection of renewable plants. 
Read more