'Case Study: Minnkota Power’s Milton R. Young Station Electrical System Assessment'

摘要

Minnkota Power’s Milton R. Young Station Unit 1 was put into service in 1970 the original electrical distribution equipment is approaching 40 years of age. Over the years, it has been expanded to support plant additions. Electrical distribution equipment typically has a 20 to 30 year reliable life, after that period, life extension measures such as retrofitting, refurbishment, or equipment replacement is necessary to maintain a reliable electrical system. With the demand for electric power expected to increase by about 25 percent, over the next ten years. Minnkota Power’s Milton R. Young Station has begun major efforts to perform life extension projects of major equipment such as the turbines and generators. In addition, over the next few years Milton R. Young Station will install mandated air quality control equipment. For these types of projects to be successful, the electrical distribution equipment at Milton R. Young Station needed to be evaluated. The evaluation included a feasibility assessment to analyze alternatives ranging from replacing the existing electrical equipment with new equipment to continuing to perform maintenance on the aging equipment until failure occurs. This paper will discuss how Milton R. Young Station developed a strategic plan for electrical system replacement projects, by performing a feasibility study. The paper will detail how qualitative and quantitative assessments of existing electrical equipment were used to develop a Master Plan for electrical equipment replacement. This paper includes details on evaluating the mechanical integrity of the equipment and discusses how load flow, short circuit, and arc fault studies were used in evaluating the existing equipment. The concepts of reliable electrical systems and the use of IEEE Std 493, "IEEE Recommended Practice for the Design of Reliable Industrial and Commercial Power Systems" are detailed. The conversion of failure probability to risk cost will also be discussed. Finally, this paper will cover the implementation process including performing equipment risk ranking, and developing a generic phased approach for completing the upgrade program.