Model guide

Enercon E-70 E4

Enercon’s gearless 2 MW-class model: 2.3 MW rated power, 71 m rotor. The rotor drives a multi-pole synchronous annular generator directly; there is no gearbox in between. In the field, attention moves from the gearbox to the generator, the pitch system and the converter.

What defines this model

In the Enercon design the inner ring of the generator turns together with the rotor. Speed is low (6–21 rpm), so the generator is multi-pole and large in diameter. The variable-frequency power is rectified and converted to grid frequency by the Enercon converter.

Without a gearbox, gear oil changes, oil sampling and gearbox bearing failures drop off the list. Generator cooling, the pitch system’s emergency supply and the converter modules take their place.

Key technical data

Drivetrain and systems

Annular generator

• Large-diameter and multi-pole; heat and clean air paths are the most critical periodic items in this design. On dusty and salty sites a clogged air path comes straight back as a temperature warning.

Storm control

• Classic designs stop the turbine completely at a set speed. Enercon reduces speed and power gradually as the wind rises, so the turbine keeps producing partially in high wind.
• Low power in high wind can look like a fault; the control system may simply be working as designed.

Pitch and emergency supply

• Each blade has its own pitch system and emergency energy source. The capacity test of that source, which feathers the blades on grid loss, should never be skipped.

E-70 and E-82 (Enercon)

Maintenance topics that matter in the field

• A slow rise in generator temperature: check the cooling air paths and filters first.
• Pitch emergency supply: capacity test and connections.
• Yaw: adjustment gears and lubrication; the first place to look for hunting and noise.
• Converter modules and cooling: read temperature and fault logs together under load.

Sources

• ENERCON E-70 E4 teknik veri (BAPE dosyası, PR1)