Requirements for commissioning

Commissioning is the process of testing that every element of a plant is properly installed and functioning correctly. This takes place at the end of construction, before beginning production operations and handing the plant over to the owner or to the operations manager. For the purposes of the GPM PPC, commissioning involves testing only the inverters.

Important:

The grid operator and GPM must agree on the requirements for the acceptance tests before commissioning the GPM PPC.

The GPM Power Plant Controller (GPM PPC) controls the entire renewable power plant (RPP) according to your plant's specifications. At the time of commissioning, the plant must meet the following requirements:

  • All connected devices are commissioned and feeding electric current into the utility grid.

  • The communication network is installed, and the system can reach all devices involved in the control system.

  • Remote access to the system network is available.

  • Scheduling takes the weather forecast into consideration.

  • Depending on the cybersecurity policies of your organization, it may be necessary to be able to connect to the system through a VPN for commissioning, services and maintenance purposes.

Depending on the behavior of the inverters, it may be necessary to adjust their parameters to fine-tune their performance.

The following points must be guaranteed before the GPM PPC commissioning:

  1. The Power Meter is measuring at the Point of Interconnection (POI).

  2. The Power Meter has a scale factor that allows measuring from the minimum and maximum readable parameters according to the power flow specifications at the POI.

  3. The Power Meter can publish at least the following measurements:

    • Total AC Active Power
    • Total AC Reactive Power
    • Frequency
    • Power Factor
    • Voltage A-N
    • Voltage B-N
    • Voltage C-N

  4. The Power Meter is available through Modbus TCP protocol and reachable from the GPM monitoring devices.

  5. The Power Meter publishes the new measuring values at the Modbus Map within the timeframes stipulated by the grid operator (for example, less than 100 ms).

  6. The Power Meter is successfully commissioned and tested.

  7. At least, the 90% of the power converters are successfully commissioned and energized.

  8. The Power Converters or Controllers are available through Modbus TCP protocol and reachable from the GPM monitoring devices.
    Note: If the inverters use protocols other than Modbus TCP, a protocol converter is required. The protocol converter may be provided by GPM or a third-party provider.

  9. The Power Converters or Controllers must be successfully configured and tested to:

    • Respond to the external setpoints for active power (P) and reactive power (Q) through Modbus TCP protocol.

    • Not respond with a power ramp dynamic. If this feature is necessary, the power ramp response must be performed by the GPM PPC.

    • Not have any limitation of Power Factor.

  10. In an open-loop test, the Power Converters or Controllers must reach the steady state response in less than a fifth part of the Grid Code specification within the accuracy established.
  11. The available active power to tune the controllers of the GPM PPC must be greater than the 50% of the rated power of the plant.
  12. The minimum time window required to perform to perform the full commissioning of the GPM PPC with the utility grid permissions is equal to six hours.
    Important: The time frames may change depending on the specific requirements of each client, as well as limitations of the plant and its grid.
    Item Name Description Tentative schedule [min]
    1 GPM Monitoring GPM services testing. 60
    2 Open loop Setpoint sending directly over the inverters. 30
    3 Active Power P loop calibration with 0.1 per-unit (pu) steps. 60
    4 Reactive Power Q loop calibration with 0.05 steps. 60
    5
    1. Voltage setpoint

    2. Voltage reference
    1. Vs loop calibration with 0.005 steps of Vnom.
    2. AVR test within the Grid Code with V simulated.
    		 60
    Note: Depending on the Grid Code, the voltage regulation is done either though a voltage reference or through a setpoint control. Only one control will be scheduled.
    6 Power Factor PF test within the Grid Code bounds. 30
    7 Frequency Droop Over & Underfrequency tests with simulated values. 60