Transmission expansion planning in presence of large RES penetration: The case of Italy

Advanced Technologies for Future Transmission Grids

“…Power electronics has revolutionised the use of phase shifters in power system control because the replacement of the traditional mechanical tap changers by thyristor valves (to obtain the thyristor-controlled PST or TCPST) has increased the response speed of phase shifters and made them effective for the enhancement of both small disturbance and transient stability (see [184,193,195,11,206] [193]. This element consists of two (or more) SSSCs [206] installed in two (or more) lines and connected at their DC terminals.…”

“…Nowadays, an estimation of worldwide installed SVCs exceeds 600 devices for a total installed power of over 90 GVA [184,204,206].…”

“…In this application (operating since 1999), the TCSC system is utilised for oscillation damping and transient stability enhancements. The newest applications have been carried out in India and in China [184,204]. Nowadays, an estimation of worldwide installed TCSCs amounts to 10-15 devices (of which only one in Europe so far, at Stöde substation in Sweden) for a total installed power of over 2,000 MVA [184,206].…”

Topological Considerations on the Use of Batteries to Enhance the Reliability of HV-Grids

“…As a consequence, the uncontrollable and uncertain nature of RES poses new challenges to the operation of power systems, possibly affecting their reliability. Several viable solutions have been investigated in the recent scientific literature, such as demand management [3], the upgrade and expansion of the transmission grid [4], and energy storage systems. As network renovation and expansion may not be always technically feasible [5] and encounter strong public opposition [6], energy storage systems can defer large investment in high-voltage and distribution grid assets [7,8], while increasing transmission capability [9].…”