Planning and operation of multi-area power systems under market conditions: a direct method to differentiate the market price on each node of a triangular mesh

The Italian ISO is going to update the multi-area representation of the Italian electric system with meshed interconnection schemes, whose maximum complication may reach a certain number of triangular meshes, each other radially interconnected. This paper proposes a direct (non-iterative) method to settle the market price in each area at the vertices of a triangular mesh, with the objective of maximizing the overall social benefit. The problem is a quadratic programming one, and it is solved implementing the Kuhn-Tucker optimality conditions by means of a particular technique avoiding iterations, called "geometric engine" and already well experienced on radial interconnection schemes. This approach is rigorous and first of all rapid, as well as robust and rather simple. The technique is described in detail and numeric examples are provided. It is applicable not only to problems of price clearing in multi-area power systems under market conditions, but also to problems of conventional dispatching. This paper has been funded as a "Ricerca di Sistema", according to the decree of the Italian Ministry of Industry DM MICA 26/01/2000.