Coordinated reactive compensation in a Wind Park

Abstract

In wind energy, an incentive payment related to the reactive power compensation is applied. In the past, the maximum incentive was achieved when the cos phi, that was calculated as a monthly mean, was almost unitary (cos phi = 1.00). The payment is a percentage of the average reference tariff (ART). Since the 1st of January 2007, the Spanish regulation RD 436 /2004 has modified the incentive payment. Nowadays, it is calculated each 15 minutes from the energy during this period, and its maximum value depends on the achievement of a objective power factor (cos phi) which is defined in three time frames: peak hours (cos phi < 0,95 cap.), valley hours (cos phi < 0.95 ind.) and flat hours (cos phi = 1.00). To maximize the incentive payment, in the Sotavento Experimental Wind Park (Spain) a configuration with a central controller that coordinates the actuation over all the capacitor steps in the wind park has been installed. In this article, a central controller algorithm which is based on a dynamic programming is proposed. Its main objectives are: to maximize the incentive payment, or achieve the equivalent objective PF, and to minimize the number of connection operations over the capacitor steps (especially those in substation). At the present time, the algorithm is being tested in the wind park.