Principal Investigators: Dr. Roy McCann, Dr. Alan Mantooth
The increasing capacity coming from inverter-based generation presents many challenges to maintaining NERC-mandated reliability levels in the bulk electric power system while also supporting the operation of electricity markets. Given that much of the increased renewable generation will come from solar PV plants with increasing capacity in battery energy storage, there is increased consideration for hybrid ac and dc transmission systems. In particular, integrating dc power sources through multi-terminal configurations potentially has many advantages for meeting future electricity demands. This research proposes a power electronic circuit configuration that enables hybrid ac and dc transmission operations with improved reliability compared to existing methods.
There have been numerous publications with multi-terminal HVDC systems. This research provides a new approach that overcomes concerns over integrating ac and dc transmission systems. The completion of this project will provide a higher degree of grid stability and ensure reliable and continued operation of utility-scale power systems that include increasingly large amounts of inverter-based generation. The integration of PV plants and BESS with the proposed multi-purpose back-to-back multilevel inverter will provide operation at transmission-level voltages. The proposed configuration will also enable increased use of demand response programs while providing for stable and reliable operation of future electric power systems with increasing amounts of distributed generation. This will be achieved in a cost-effective manner by integrating multiple applications such as the BESS (voltage/frequency regulation, peak shaving), PV plants (injecting active power) and grid stabilization features.