5. Conclusion

The opening up of electricity markets and the strengthening of interconnections are factors that could lead to greater active (and, by contrast, reactive) power flows, and above all, more variable over time. The role of frequency and voltage control is therefore unlikely to diminish.

Controlling system safety (ensuring normal system operation, avoiding major incidents, which 2003 showed were still possible in North America and Italy) remains a fundamental challenge.

While the technical principles for controlling and regulating voltage and frequency, and ensuring stability, have been tried and tested (although technical advances are always possible), one area of work consists in precisely defining the needs of network operators to perform these functions, as well as the technical, contractual and financial relationships to be set up between...