WIND TURBINE PITCH

Part 2 in the BETTER WIND series of articles about the innards of wind energy: Each story is a small example of the parts and products necessary to turn wind into wind energy. Each one adds to the economic boom that is renewable energy. (And, in this case, it ironically seems that the German multinational is outsourcing work to the U.S.)

Hydraulic Pitch Drives for Wind Energy Turbines
August 3, 2007 (Automation)

WHO
Bosch Rexroth, part of the Bosch Group.

A see-through model of the complex three-dimensional gearing mechanism the pitch drive helps operate.

WHAT
The company’s pitch drive automatically guides a wind turbine’s mechanism through wind shifts to maximize efficiency. As the wind speed increases, the pitch drive turns the blades away from the wind to maintain a steady energy output. If the wind becomes destructively powerful, the pitch drive brings the blades to neutral.

WHEN
2006: Bosch-Rexroth earned $2.6 billion. (They are apparently doing something right.)

WHERE
Bosch Rexroth has 500,000 customers in 80+ countries. It is based in Hoffman Estates, Illinois. The Bosch Group is based in Germany.

A view into the turbine.

WHY
- The pitch drive allows wind farm operators to match energy output to grid demand.
- The essential mechanism is smooth hydraulic drives combined with computerized intelligence to respond automatically or to programming. (Click through to article for engineering details.)
- Rexroth pitch drives are designed to require little maintenance.
- Parts are engineered to function in extreme conditions and backup systems prevent failure.

The pitch drive.

QUOTES
“Wind turbine pitch drives significantly reduce the forces that act on the basic structure and the mechanics of the wind turbine, protecting it from damage, excess wear and tear, and generator malfunction.”