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Ultracapacitors Improve Reliability for Industrial wind turbine Pitch Systems

By Adrian Schneuwly Maxwell Technologies, SA – Rossens, Switzerland

Introduction

Today’s advanced wind turbines are three-bladed, variable speed turbines. The rotor blades are adjusted and controlled via three independent electro-mechanical propulsion units for the pitch systems. On a pitch controlled wind turbine the turbine's electronic controller checks the power output of the turbine several times per second. When the power output becomes too high, it sends an order to the blade pitch mechanism, which immediately turns the rotor blades slightly out of the wind. Conversely, the blades are turned back into the wind whenever the wind drops again. Thus aerodynamic efficiency and reduced loads on the drive train is assured, providing reduced maintenance and longer turbine life. To enhance the level of safety, newer wind turbine technology uses the wind not only to produce wind energy but also for its own safety. The converters feature aerodynamic braking by individual pitch control. The rotor attains the full braking effect with a 90 degree off position of all three blades. Even if a blade pitch unit fails, the other two rotor blades finish off the braking process safely. To enhance the level of safety each of the autonomous pitch systems is equipped with an emergency power supply manufacturer to immediately ensure the reliable functioning of the fast blade pitch system in the event of a total power failure or for maintenance purposes.

Three bladed wind turbines Independent electro-mechanical pitch propulsion units

Maxwell Technologies, Inc. Maxwell Technologies SA 9244 Balboa Avenue, San Diego, CA 92123 CH1728 Rossens United States Switzerland Phone: +1-858-503-3300 Phone: +41 (0) 26 411 85 00 Fax: +1-858-503-3301 Fax: +41 (0) 26 411 85 05 © Maxwell Technologies, Inc. | www.maxwell.com | info@maxwell.com |