A NEW SUBSTATION LEVEL DISPATCHING APPROACH TO INCREASE THE NETWORK CONTROL AND PERFORMANCES IN PRESENCE OF DISPERSED GENERATION

摘要

Digital Substation Automation Systems (SAS), which have been operating in the Italian EHV and HVsubstations from about ten years, can now answer to new power system functional requirementsconcerning grid operation, power quality and enhanced equipment monitoring.The dispatching and control opportunities offered by the digital technology appear suitable to face thenew operation needs of transmission and distribution grids, arising from the connection of a growingamount of dispersed generation, even more supplied by the so called Renewable Energy Sources(RES), that, generally, are highly intermittent, with limited frequency and voltage control capabilitiesand often concentrated in areas with a weak and unmeshed transmission system, so leading to criticaloperating conditions.A possible solution to the above mentioned issues could come from a new decentralized and smartapproach to network control, in normal and emergency condition. The proposed decentralizedapproach can help the TSO to exploit the distributed generation in order to improve the supplyreliability, to optimize the use of the available network resources and, finally, to defer gridinvestments.This paper shows some innovative applications for a decentralized active and reactive power control ina portion of the HV network, as a first results of a research activity carried on by the italian division ofSiemens with the technical support of Terna, the Italian TSO. The described innovative applicationsare finalized to decentralize the voltage control, to the management of power flows and to theislanding operation, with the aim to optimize the RES integration in the electrical system.The new proposed algorithms will be then implemented and tested in a digital Substation AutomationSystem (SAS) framework, a prototype of a Terna standard digital SAS project.Afterwards, new functions will be spread, shared and able to operate in many interconnectedsubstations, so that the new grid management opportunities will be available to a higher extent.