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A Study of the Parameters Influencing the Capacity Credit of WECS- A Simplified Approach
Sushil Patil, Student Member, IEEE, and R. Ramakumar, Life Fellow, IEEE
Abstract--In recent years, penetration of wind generated electricity into power grids has been increasing significantly. During the last few decades, wind energy has doubled in capacity every three years. Because of the intermittent characteristics of wind power, it is usually difficult to determine an acceptable penetration level to maintain specific reliability requirements. The need for better capacity credit assessment for wind electric conversion systems is clear. Considerable work has been done in the past to estimate the capacity credit of WECS (wind electric conversion system) and several approaches have been proposed. This paper examines the influence of different parameters on the Capacity Credit using a simplified approach based on an effective forced outage rate (FOR) for WECS. The parameters considered are penetration level, amount and variability of load, generation configuration and wind regimes. Index Terms— Capacity Credit, Wind Electric Conversion System, Annual Load Duration Curve, Wind Penetration, Generation Configuration Electric power systems must have sufficient reserves so that generation is always adequate to meet varying customer demand. Because electricity demand cannot be known in advance with certainty, and also because generators, transmission lines and distribution systems can experience forced outages, a capacity margin requirement is necessary to maintain reliability [4]. Capacity Credit (CC) assigned to WECS is the fraction of its installed capacity by which conventional power generation capacity can be reduced without affecting the benchmark quality of supply [5]. It can always be thought of as the amount of conventional generation that could be ‘replaced’ by