Prerequisites for synchronisation

The following conditions must be met before synchronisation:

  • Elering has issued an energisation operational notification, and the client has obtained an approval for and verified the functioning of signals and controls in Elering’s direction at least seven days before the requested date of synchronisation of the generating unit.
  • The grid connection to be ensured by Elering and the consumption point are ready to be taken into generation-oriented use.
  • The client’s electrical installation is ready to be taken into generation-oriented use and the client’s generating unit is ready to be synchronised.
  • The client submits a synchronisation application to Elering at least seven days before the requested date of synchronisation of the generating unit.
  • Elering has approved the comprehensive electrical design documentation for an electrical installation drawn up by the client, which has been approved by Elering seven days before the requested date of synchronisation. The electrical design documentation includes, among other things:
  • type test reports for every type of power-generating facility;
  • report on the simulation of cooperation between the generating unit and the electricity network;
  • PSS/E and PSCAD models.
  • Elering has approved the acceptance test plan for the generating unit drawn up by the client, which must be approved by Elering seven days before synchronisation.
  • In the case of synchronous generators, Elering has approved the results of no-load tests of the generating unit, which must be submitted at least fourteen days before the requested date of synchronisation of the generating unit.
  • The client has made all the payments required by the date of energisation to Elering and properly performed all other obligations provided for in legislation and the contract entered into between the client and the transmission system operator.
  • The client has obtained an approval for and verified the functioning of signals and controls in Elering’s direction and the form for information volume table provided in section 5 of this guideline at least seven days before the requested date of synchronisation of the generating unit.
  • A temporary network contract has been entered into, permitting the generation-oriented capacity of the grid connection.

Following synchronisation, the client verifies the correct functioning of all the signals, including measurements and controls, set out in the technical design documentation with the energy system control centre and submits the signal test report to Elering following the synchronisation.

The verification and certification of the conformity of a generating unit shall take place in accordance with the provisions of the connection contract, the Connection Conditions, the RfG, the Grid Code, and the Electricity Market Act. The conformity of a generating unit with the established requirements is assessed at the connection point between Elering and the client.

Carrying out tests

Tests are generally carried out in three stages:

Certification of conformity

Once all the agreed tests have been successfully carried out, Elering shall provide an assessment of the conformity of the client’s generating unit with the requirements set out in the Grid Code, the RfG, and the connection contract. The final operational notification is issued by Elering once the requirements specified in the connection conditions have been met.