Transelectrica SA core activity is electricity transmission through the Power Transmission Grid (PTG) consisting of power substations and lines. PTG is the power grid of national and strategic interest with a rated voltage higher than 110 kV.
The equipment park managed by Transelectrica SA consists of :
78 power substations, of which :
1 substation of 750 kV
35 substations of 400 kV
42 substations of 220 kV
9028.8 km of overhead lines, of which:
154.6 km 750 kV
4740.3 km 400 kV
4095.9 km 220 kV
38 km 110 kV (lines of interconnection with the neighboring power systems)
and 212 main transforming units totaling 36.343 MVA, as follows:
2 x 1250 MVA
2 x 500 MVA
22 x 400 MVA
25 x 250 MVA
80 x 200 MVA
1 x 100 MVA
2 x 63 MVA
7 x 40 MVA
26 x 25 MVA
1 x 20 MVA
31 x 16 MVA
11 x 10 MVA
2 x 5.6 MVA
To observe the quality requirements included in the Technical Grid Code and in the License of Power Transmission and System Operator granted to CNTEE Transelectrica, the company is running a rigorous maintenance program for the PTG facilities technical condition. The maintenance program mainly aims to increase the operational reliability of the PTG and prevent unexpected accidental events for the power grid, for the people or the environment.
The maintenance actions shall be determined by considering the investment programs (retrofitting, modernising and development) and are correlated with them – as regards both the stations and the electrical lines. The maintenance programs developed within the PTG included also major maintenance actions, based on some projects on the substation or OHL in full, considering activities developed practically at all the functional units and which also enable by the investment component the development, modernization or retrofitting and preparation of the substations for being telecontroled.
Due to the extremely fast technological progress and when the life cycle of the most equipment is more than 30 years, there have been implemented modernizing and retrofitting elements enabling the operation at the latest technical level by replacing the obsolete items and installing additional facilities, new technologies inclusively.
Services/activities of maintenance are carried out in the PTG as follows:
corrective – post fault detection, including all actions needed to restore an equipment for operating at the required level;
preventive – prophylactic to prevent faults and to diminish the fault potential, aiming to reach an appropriate balance of these activities, function of the influence of various facilities on the goals proposed for the PTG: operational reliability, availability, efficiency.
The maintenance services/activities are meant to promote the new solutions both to develop and implicitly to maintain corridors, live work techniques, on-line treating the insulation of the transforming units, to shorten the outage periods and avoiding the congestion costs and the ancillary consumption etc.).
Out of the underway maintenance projects on power substations and OHLs it is worth mentioning the work carried out at the substations FAI, Baia Mare 3, Stupărei, Peştiş and at the 220 kV Bucureşti Sud – Ghizdaru OHL, 220 kV Dumbrava – Stejaru OHL, 220 kV Peştiş – Mintia OHL.
The trend by months of the fault number in between 2002 - 2008
Balancing market operator
