Generating unit testing

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

If generation equipment with different types of technology and which must meet different requirements are connected to one connection point, e.g. a synchronous module and a power park module (collectively referred to as a hybrid module), tests are carried out both on the generation equipment separately to demonstrate compliance with the RfG requirements at the connection point and on the entire installation as a whole.

NB! Power park modules are generation equipment based on wind, solar and battery storage, and all others are synchronous modules.

Tests are generally carried out in three stages:

• quality measurements;
• functional tests of the generating unit, after which the client submits a report on the test results to the network operator and the network operator gives its assessment on the report. Elering has drawn up a sample test report for power park modules and a sample test report for synchronous power-generating modules, which can be used as a basis for drawing up the test report;
• FRT test.

Certification of conformity

The granting of the synchronization permit also starts the temporary operation notice period, which lasts a total of 24 months, or 2 years. During this period, the client must submit verified models to the transmission system operator. Verified models can be submitted after the production equipment has been declared compliant.

After verifying the models, the transmission system operator issues a final operation notice and concludes a permanent network contract with the subscriber.