Siemens Energy, Inc. recently and successfully commissioned its pad-mount transformers at the Flat Water Wind Farm. The transformers, rated at 1,750 kVA, three-phase at 60 Hz, are connected to wind turbines and are used as generation step-up transformers. They are meeting three unique wind farm electrical requirements that affect the usage of pad-mounted transformers: operation as a step-up transformer, over-excitation requirements and the need for enhanced insulation with greater basic impulse insulation level BIL. Siemens was responsible for design, manufacturing, delivery and commissioning.
Located in southern Nebraska's Richardson County and Kansas' Nemaha County, the 60-megawatt (MW) Flat Water Wind Farm comprises 40 1.5-MW wind turbines and has the capacity to power more than 16,000 homes with clean, renewable energy. The project is owned by Flat Water Wind Farm, LLC, which is a partnership between Gestamp Wind North America, a subsidiary of Gestamp Renewables, and Banco Santander, S.A. Siemens was sub-contracted by Renewable Energy Systems Americas Inc. (RES Americas), the balance of plant (BOP) construction contractor.
"Siemens has been a strong and reliable technology partner that did an excellent job in identifying and creating the best transformer solution for this project," said Chris Hills, Vice President Construction of Renewable Energy Systems Americas Inc. "We are proud that the Flat Water Wind Farm is online and that it will now create a significant amount of clean energy for Nebraska."
The peak elevation for the installation is 3,280 feet with a maximum ambient temperature of 40 degrees Celsius. The pad-mount transformer is compartmental type, self-cooled, as well as tamper- and weather-resistant, and it conforms to the enclosure security requirements of ANSI Standard C57.12.28 (Pad-Mounted Equipment-Enclosure Integrity).
"Our broad range of products and solutions enables our customers to become more energy efficient, environmentally friendly and competitive," said Andrew Lawless, Vice President and General Manager of the Transformers business at Siemens Energy, Inc. "Our participation in projects like the Flat Water Wind Farm underscore the company's commitment to sustainability, and we are committed to growing the pad-mount transformer market in the USA to support integrating renewable energy into the (smart) grid."
Step-up transformers for wind farms require a different design than typical distribution pad-mount usage. Due to generator harmonics, wind farm transformer designs will be subjected to generator-related duties not seen in typical four-wire utility applications. Siemens anticipates the possibility of over-excitation when wind gusts create turbine over-speed beyond rated range, thus sustained overvoltage is automatically incorporated in its wind farm pad-mount transformer designs. Because wind farms are frequently sited on ridges and in isolated areas where lightning strikes are fairly common, another wind farm pad-mount development is "reinforced" insulation rated at 200 kV BIL for superior insulation safety margin.
Siemens understands the complete energy conversion chain and is able to transform today's grid into a living infrastructure that is smart enough to respond quickly, flexibly and comprehensively to society's energy needs. Siemens also incorporates solutions for commercial and industrial applications as well as smart homes, including building automation, IT systems integration, advanced lighting technology and energy efficient appliances for a comprehensive Smart Grid solution.
The Siemens Energy Sector is the world's leading supplier of a complete spectrum of products, services and solutions for the generation, transmission and distribution of power and for the extraction, conversion and transport of oil and gas. In fiscal 2010 (ended September 30), the Energy Sector had revenues of approximately EUR25.5 billion and received new orders totaling more than EUR30.1 billion and posted a profit of more than EUR3.6 billion. On September 30, 2010, the Energy Sector had a work force of more than 88,000. Further information is available at: www.siemens.com/energy.
Source: PR Newswire