Hydro-Quebec experience with PSS tuning

Hydro-Quebec has added several facilities on its transmission system, including a sixth 735 kV 950 km AC line from the James Bay region, a HVDC link of 1050 km at 450 kV with 3 rectifier-inverter substations between Radisson-Nicolet-Sandy-Ponds, 11200 MVArs of series-compensation and 4680 MW of new generation. These additions modified the overall system behavior significantly. Therefore, a task force was initiated to assess the adequacy and revise on a large scale basis the AVR and PSS settings. This paper first presents the tuning and coordination approach used by the task force. Then the benefits achieved are illustrated with the new settings installed on all 26 stabilizers present in the system. From this number, 21 will be modified during scheduled maintenance over the next few years. TransEnergie expects a significant damping improvement of the major oscillatory modes, with a corresponding ≃400 MW increase of its transmission capability on several 735 kV corridors