GODA - grid optimisation with decentralised actors

Limiting a PV system’s output relieves the strain on grids while resulting in barely any loss of energy yield. As part of the project, a decentralised system will be set up where PV systems are comprehensively fitted with P(U) regulators.

Factsheet

  • Lead school School of Engineering and Computer Science
  • Institute Institute for Energy and Mobility Research IEM
  • Research unit IEM / Photovoltaic systems
  • Funding organisation Schweizerische Eidgenossenschaft (Bundesverwaltung)
  • Duration (planned) 01.11.2021 - 01.07.2023
  • Project management Prof. Dr. Christof Bucher
  • Head of project David Joss
  • Project staff Peter Wüthrich
    Luciano Borgna
    Marco Pascal Zaugg
  • Partner Bundesamt für Energie BFE
    Groupe E SA
  • Keywords Active power control; grid connection of photovoltaic systems; P(U); SmartGrid; grid stability; grid integration; renewable energies; decentralised connection of energy generation systems

Situation

Distribution grids are still scaled to almost worst-case scenarios in terms of decentralised feed-in. However, these scenarios are both unrealistic and irrelevant from an energy perspective. Smart inverters with local regulation mean such scenarios are now outdated. This is why Groupe E wants to configure decentralised photovoltaic inverters to enable them to reduce their output independently and in a controlled way when grid voltage is too high. This is to be monitored and solar power producers compensated based on smart-meter data. If the project proves successful, future investment in grid expansion for decentralised energy-generation plants could be postponed for years or even decades.

Die Berner Fachhochschule prüft exemplarisch Wechselrichter im PV-Labor bezüglich der Stabilität der P(U)-Regelung.
Die Berner Fachhochschule prüft exemplarisch Wechselrichter im PV-Labor bezüglich der Stabilität der P(U)-Regelung.

Course of action

In this project, a decentralised system will be set up where PV systems will be comprehensively fitted with P(U) regulators instead of expanding the grid. Using an algorithm yet to be defined, the grid operator calculates the yield loss through the P(U) regulator and compensates the system operator. Bern University of Applied Sciences is using test cases to analyse inverters in relation to the stability of the P(U) regulator at the Laboratory for Photovoltaic Systems. The aim is to set droop control as high as possible so that the regulation of energy can be kept to a minimum.

Untersuchte Wechselrichter mit den variablen DC- und AC-Simulatoren
Untersuchte Wechselrichter (vorne) mit den variablen DC- und AC-Simulatoren

Result

P(U) could be successfully adjusted and tested on 5 PV systems in the field. The inverters show the desired reduction in active power when the grid voltage is too high. Using self-learning algorithms that evaluate the data from the smart meters, the production losses can be calculated and the producers compensated. The measurements in the laboratory show stable behaviour of the inverters - both individually and in groups - when the control parameters are set reasonably.

P(U)-Regelverhalten von 3 Wechselrichtern bei variierender Einstrahlung
P(U)-Regelverhalten von 3 Wechselrichtern bei variierender Einstrahlung

This project contributes to the following SDGs

  • 7: Affordable and clean energy
  • 12: Responsible consumption and production
  • 13: Climate action