Pursuant to Article 116 of the Energy Law

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CIRCUIT CURRENTS
 
3.2.6.1. Equipment in transmission facilities and facilities of the transmission system users 
must be dimensioned to meet calculated values of short circuit currents. 
3.2.6.2. In case of a short circuit, the stabile operation of transmission system must not be 
compromised. 
3.2.7.
 
S
TABILITY 
 
3.2.7.1. It has to be ensured that the transmission system operates in conditions of satisfied 
stability. In that sense, the following types of stability are analysed: 

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- stability of the rotor angle when the system is exposed to small and great 
disturbances in short time interval; 
- frequency stability in short and long time intervals; 
- voltage stability when the system is exposed to small and great disturbances in 
short and long time intervals; 
in accordance with definitions in classification IEEE/CIGRE. Short time interval is 
considered to be the first 3-5 seconds after disturbance has occurred, i.e. 10-20 seconds for 
very large systems with dominant oscillations between the areas. Long time interval is 
considered to be the first 30 seconds for oscillations of synchronisation power between 
machines, i.e. 15 minutes after disturbance has occurred for transient processes of secondary 
control. 
3.3.
 
TRANSMISSION
 
SYSTEM
 
DEVELOPMENT
 
PLAN 
3.3.1.
 
M
ETHOD OF TRANSMISSION SYSTEM DEVELOPMENT PLANNING
 
3.3.1.1. JSC EMS develops and publishes the Transmission System Development Plan every 
year. The Transmission System Development Plan is prepared for the upcoming ten-year 
period, taking into consideration investment needs for the first five year individually, and for 
the remaining five years indicatively.
3.3.1.2. Development of transmission system is planned in a way that allows flexible 
operation of generation capacities in all foreseeable modes of the transmission system 
operation.