SCOPE
Design, Supply, Erection Supervision and Commissioning of 11 kV, 2x ±4 MVAr Containerized Statcom Systems for 66 kV Bus Voltage Regulation.
PROBLEM
66 kV voltage will vary after installation of Nevertire SF rated 105 MW, which is connected to the Essential Energy network.
REQUIREMENT
Fluctuations in Solar Farm output must not produce more than the allowable voltage changes as per AS 61000.3.7
SOLUTION
- Installation of 2 Statcom Systems rated ±4 MVAr at Eulomogo Substation at 11 kV bus.
- Each Statcom System is connected to 11 kV bus via 4.5 MVA, 11/0.48 kV coupling transformer.
- Parallel operation of 480 V, ±400 kVAr forced air-cooled Statcom Panels are implemented.
- 20 panels inside 4 air-conditioned containers are operated in parallel by a Master Controller, which generates a set point for inductive/capacitive reactive power as per droop characteristics specified for 66 kV bus.
- The overload rating of the Statcom System is 3xInom for 2s.
TEST RESULTS
The voltage reference test was completed successfully at the of December 2019 in coordination with Essential Energy. Test results showed the ability of the Statcom System to operate according to the required droop control characteristics.
ACCEPTANCE CRITERIA | Pass |
The reactive power output at 11KV busbar voltage level corresponds to the expected output as per the given droop characteristic within acceptable tolerance limits (+/- 10%) | Yes |
The output of the STATCOM unit can be maintained for the duration that the tap is held. |
Yes |
The settling time of voltage response to the tap change is sufficient for the Nevertire solar farm to comply with its GPS requirements. | Yes |
Measurement data is successfully downloaded and confirmed. | Yes |
BENEFIT
Grid Requirement Meet
Grid Operator allowed solar power plant to connect
to the grid.
Safe Operations
Safe Operation for all equipment in the system
is achieved.
Revenue
As grid requirement is met, Nevertire solar farm can operate.