Prefeasibility Study for Technical Solution of Connection of Wind Farms (72MW) to the EPS of Montenegro

Objective of the Pre-feasibility study is realization of first phase of connection of wind farms (WF) in Niksic area, with a power of 72MW, to the transmission network of Montenegro, taking into consideration transmission development plans of 400, 220 and 110kV network until 2014.

The study answers and give evidence, using a model calculation, under which conditions it is possible to install, operate with and connect objected wind farms to the transmission network of Montenegro in Krnovo site. Two connection variants have been analyzed.

Taking into consideration the lack of space in existing SS Niksic (currently, there is not enough space for more than one bay), for one of the variant, as a starting point for analysis, new substation Ozrinići near Niksic on 110 kV voltage level was considered.

Power plants will be connected to the transmission network on one of the following ways:

1. Connection to new SS 110 kV Ozrinici through two 110kV OHLs
2. Connection to SS Brezna through one 110kV OHL and to SS Niksic through one 110kV OHL

For Variant 2 existing SS Brezna is necessary to be in operation on 110 kV (currently operate under 35 kV voltage level). For each variant load flow, voltage profile analyzes (including static security analysis) and assessments of investment costs were performed, based on which the potential variant is proposed. In other words, the proposal that meet both, the technical requirements of connecting and low investments, is given. For all variants short circuit calculations have been performed, where results pointed out to a certain level of increase in the value of short circuit and their impact on existing and new equipment of lines and transformer stations.

Instalation of “phase shift” transformer in HPP Perucica and its influence on load flows through transmission network of EPS of Montenegro was also analyzed. Results have shown that “phase shift” transformers installation in HPP Perucica enable realization of second phase of wind farms in Krnovo site, with total capacity 139.2MW (72+67.2MW).

Type of services provided:

• Load flow and voltage profile studies
• (n-1) static security analysis
• Techno-economical aspects
• Short circuit analyses according to IEC 60909
• Installation of “phase shift” transformers in HPP Perucica and its influence on second phase installation of WFs in Krnovo location