Application of interruptible contracts to increase wind-power penetration in congested areas

Wind-power penetration in many cases faces significant barriers due to limited transmission capability. In Greece (and in most countries in Europe), the guaranteed access to the grid offered to wind parks, in conjunction with the existing planning practices, has led to severe limitations in wind power installed in certain congested areas. This paper presents some simple ideas that are currently being applied to the Hellenic Interconnected System, in order to increase the wind-power penetration. The main concept is the introduction of interruptible generator contracts and the control of the power flow through congested corridors by issuing power reduction commands, whenever security limits are violated., The proposed control is implemented using common PLCs of low cost and the existing SCADA system, and is both simple and transparent. The paper presents also a methodology to assess the impact of the proposed techniques on the wind penetration achieved.