Performance and cost

Strategy is worked out for market introduction and integration in wind turbines.

Benchmark to other drive train solutions are carried out:

  • In cost per torque unit
  • Costs of active materials: lamination, windings, permanent magnets
  • Cost of supporting mechanical parts and frame
  • Cost of cooling devices: Fans, heat exchangers

The benchmark to conventional geared drive trains expressed in cost per kNm torque is essential and challenging. Furthermore efficiency and maintenance and repair costs are important in order to benchmark life cycle cost.

Planning of lean production and assembly based on deliveries of parts from various manufactures.

Creation of functional specification and interfaces towards the frequency converter and mechanical support.

The direct drive train has a higher efficiency than the geared train resulting in lower heat losses and around 2% higher energy efficiency. The permanent magnets are based on rare earth elements (REE), where the price fluctuated largely in 2011 due to speculation in raw materials. The REE neodymium is not rare, but has natural resources as large as lead. The challenge is to secure the pricing of permanent magnets in purchase for longer periods.

Simplicity is the characterizing keyword for direct drive, minimizing the number of parts and elements compared to a geared

drive train.