Connection of switching station 20/110kV Sastavci to the transmission network of Bosnia and Herzegovina

Bosnia and Herzegovina
Connection of switching station 20/110kV Sastavci to the transmission network of Bosnia and Herzegovina

client: HYDROENERGY, Gacko and DRINA HYDROENERGY, Ugljevik (B&H)

type: Project Analyses (Renewable, Transmission, Generation)

finishing date: May 2010

team: M. Cokorilo - Project Leader, M. Vukovic and S. Markovic – Consultants, A. Oros, N. Jovic, B. Sijakovic

Objective of the Study is connection of 6 new small hydro power plants in Tjentiste region (estimated total power 19.15 MW) to the transmission network of Bosnia and Herzegovina, through switching station 20/110 kV Sastavci, taking into consideration transmission development plans of 400, 220 and 110 kV network until 2011. In accordance to that all analyses were performed for that year.

Study of technical solutions for the connection switching station 20/110 kV Sastavci, is made from the aspect of electricity evacuation to the EES BiH, taking in consideration security criteria and respecting the criteria of least cost for building the connections.

Switching station will be connected to the transmission network through a 110 kV OHL two different variants were analyzed for the connection to the transmission network:

  1. connection with double 110 kV OHL to SS Gacko
  2. connection with single 110 kV OHL to SS Gacko

Load flow, voltage profile analyzes and assessments of investment costs were performed for each variant, based on the proposed potential variants. In other words, the proposal that meet both the technical requirements of connecting and low investments is given. On the basis of the proposed variant, parameters of block transformer (power, ratio, regulation) and generator power factor are defined. Calculation results pointed out the value of short circuit in internal 20 kV network and its impact on existing and new equipment in connection point.

Static stability analyses (for small disturbances) have been performed with analysis of eigenvalues. As a result of the analysis of the stability for small disturbances, Study has provided the basic parameters of generators and block-transformer on the connection site, as well as the estimation of static stability and the possibility of synchronization power in the expected conditions.

Type of services provided:

  • Definition of parameters of block transformer (power, ratio, regulation)
  • Load flow and voltage profile calculations
  • Static security analyses
  • Techno-economical aspects
  • Short circuit analyses according to IEC 60909
  • Static stability analyses