TSO/DSO Coordination for Voltage Regulation on Transmission Level: A Greek Case Study

This paper primarily aims to demonstrate how TSO, and DSO shall act in a coordinated manner to procure, and activate innovative flexibility services in a reliable, and efficient way. The objective of this paper is to demonstrate the financial, and system reliability benefits the TSO can exhibit by leveraging flexibility, under different coordination frameworks between the operators, in order to alleviate overvoltages caused by Ferranti effect. For this purpose, a service-oriented flexibility market is introduced. A case study from the Greek power system is used to conduct a cost-benefit analysis of the proposed market solution to the Business as Usual voltage regulation practice, under a spectrum of different technoeconomical parameters. The results indicate that the proposed flexibility solution can have significant economical benefits for TSO to regulate voltage through DSO or TSO connected assets.