Construction of 220 kV Lafarge substation. Book 1 “Electrical solutions”, страница 11

The calculated cross sections and distribution feeder cables are checked for a valid long-term current loads, taking into account the reduction factors (if necessary), thermal stability, protection against overload and shut down a single-phase short circuit at the end of the line and to the terms of the most remote electric start. Supply and distribution cables protection against overloads and short circuits is performed by automatic circuit breakers

5.11 Building equipment layout

power supply 35kV voltage on Lafarge substation is provided complete installation of 35 kV switchgear.

35kV switchgear, according to the design brief is performed as a single partitioned  buses system and is done from cubicles F400.

Cubicles must qualify the following requirements:

- Cubicle design must provide easy replacement of damaged items, and easy maintenance works in the cubicles;

- cable line compartment must provide easy cable connections, as well as ease of work on testing and fault location of cable lines

- cubicle construction must ensure safe operation in cubicle if there is voltage on the buses

- cubicles must be provided with a stationary set of mechanical interlocks to prevent incorrect operation

35 kV cubicles in the account of nine pieces (9 pieces) are installed in 35 kV switchgear . Connection of the power transformer capacity of 63 MVA with introductory cubicles 35kV are implemented by cable lines with XLPE insulation between adjacent cubicles - copper bars.

35 kV switchgear section is consist of the following cubicles:

K1H section- 5 cubicles

-introductory- 1 item

- section switch- 1 item

- line cubicle -3 item

- voltage transformer-1 item

K2H section- 5 cubicles

- introductory- 1 item

- section switch- 1 item

- line cubicle -1 item

- voltage transformer-1 item

In the building the installation of the earthing resistor 35 kV in separate premise is provided

5.11.2. 6,6 kV switchgear

Power supply 6,6 kV voltage  on Lafarge substation is provided complete installation of 6,6 kV switchgear.

6,6kV switchgear, according to the design brief is performed as a single partitioned  buses.

Cubicles must qualify the following requirements:

- Cubicle design must provide easy replacement of damaged items, and easy maintenance works in the cubicles

- cable line compartment must provide easy cable connections, as well as ease of work on testing and fault location of cable lines

- cubicle construction must ensure safe operation in cubicle if there is voltage on the buses

- cubicles must be provided with a stationary set of mechanical interlocks to prevent incorrect operation

6,6 kV cubicles in the account of twenty five pieces (25 pieces) are installed in 6,6 kV switchgear . Connection of the power transformer capacity of 63 MVA with introductory cubicles 35kV are implemented by cable lines with XLPE insulation between adjacent cubicles - copper bars.

6,6 kV switchgear section is consist of the following cubicles:

K1P section- 5 items

- introductory- 1 item

- section switch- 1 item

- line cubicle -10 item

- voltage transformer-1 item

K2P section- 11 items

- introductory- 1 item

- section switch- 1 item

- line cubicle -8 item

- voltage transformer-1 item

5.11.3. Auxiliaries board

To supply auxiliaries consumers Lafarge substation in the building of the substation are placed two auxiliary transformers 6,6 / 0,4 kV power of 630 kVa each, and auxiliaries boards

Auxiliaries transformers installation is provided in separate rooms

The premises  also provide installation of neutral grounding resistors of 6.6 kV.

Auxiliaries board is completed a set from separate panels. The arrangement of panels is provided inside the building.

As a reserve power supply of buses switchegar-6,6kV is provided  feeding from diesel-generator installation 0,4 кВ of capacity 1600 кVА. Diesel generator installation is provided in a separate diesel generator room.

Feeding from diesel generator installation is carried out through raising transformer 0,4/6,6 кВ by capacity 1600 кVА which also is established in a separate premise