Security and Reliability Analysis for the Transmission System of Elektroprenos BiH and Measures for their Improvement

Aim of the Study is to carry out a protection system coordination analysis for the transmission system of Elektroprenos BiH, in both quasi-static and time domain. The subject of conducted analyzes is relay protection on all voltage levels within the transmission system in Bosnia and Herzegovina.

For the purpose of the Study, modeling of transmission system elements and relay protection was conducted, and systematization and coordination analysis with current relay settings was performed, in order to define measures for achieving complete selectivity of the protection system. Special attention was put on analyzing the influence of the protection system on dynamic behavior of the power system, and power system stability in general, as well as on investigating the influence of transients on specific types of protection, especially out-of step relays. For this purpose, integration between dynamic model in PSS/E software tool, and protection system model of Bosnia and Herzegovina in CAPE software tool was carried out.

Additional analyzes were conducted in order to assess the influence of planned power plants and sub stations on current relay system settings. In line with the Power system defense plan, wide-area disturbances were simulated in order to evaluate the efficiency of the protection system, and potentially define recommendations for relay system re-setting in order to preserve power system stability. According to Power system restoration plan after total system black-out, influence of re-connecting specific parts of the power system on protection system’s operation was analyzed, in order to potentially define recommendations for relay re-setting before commencing restoration procedure.

Type of services provided:

• Protection system data collection, systematization and data-base organization
• Creation of protection system model which includes relay models and protection telecommunication schemes (PUTT, POTT)
• Protection system validation according to recorder chronology of specific events
• Relay setting analysis and relay coordination analysis
• Analyzing the influence of protection system on power system stability and the influence of transients on specific relay operation (out-of-step protection)
• Defining recommendations for protection system re-setting for achieving complete protection system selectivity
• Analysis of wide-area disturbances defined in Power system defense plan, on protection system operation
• Analysis of Power system restoration plan after total system black-out, on protection system operation