News Article
PV Powers Into French Grid
The power plant controller skycontrol has been installed into a photovoltaic installation that feeds directly into France's 63 kV high-voltage grid. Drawing from experience in the control of utility-scale PV plants connected to medium-voltage grids, Berlin-based company skytron energy fine tuned the plant controller of the 34 MWac PV power plant in the south-west of France to the stringent grid connection specifications of RTE, the French transmission system operator. In addition to the control functions that by now are standard to the plant controller, such as active power curbing and power factor adjustment, the controller is empowered to meet a number of new challenges.
The four plant sections spaced from each other as far as 30 kilometres require active compensation of the reactive power load caused by long cable lines. Another trying task is the injection of reactive power into the grid for voltage stabilization, and this even at nights when no power is being generated. This is ensured by meticulously adapted control algorithms and phase-shift capability of the inverters. A further important aspect: frequency control makes sure that the frequency stays within the predefined characteristics and power generation is throttled in the event of over frequency.
During on-site commissioning and on-grid test runs, the controller was finely tuned to follow a comprehensive plant simulation model. "First we were a little apprehensive. For everybody involved, these control requirements meant treading new trails", admits Gerald Freymann, Technical Manager of GP Joule, the EPC contractor for the entire project. "But our minds were quickly set at rest by the flexibility of the power plant controller. Right now we are in the approval phase during which we have to provide the plant's logged and recorded control responses to the French RTE company. We are confident to pass this final test."
Following this successful completion of controlled PV power feed-in, skytron energy GmbH is now installing another power plant controller in a 40 MWp project in the south-east of France, this time injecting into RTE's 225 kV grid. "We are happy about the growing importance of photovoltaic power plants connected to France's high-voltage grid. And with the controllable provision of PV power we make an important contribution to grid stability," explains Marco Wirnsberger, Managing Director of skytron energy
"To date, our company has equipped 1.3 GW of installed PV capacity with the skycontrol plant controller, which clearly puts us on the market leading scale."
