12.0 Troubleshooting

100

12.2Generator

The generator is a 66 kW, 3-phase induction type generator. It is connected to the grid as follows once the PLC controller signals that the relevant conditions have been met: the brakes are released, the rotor freewheels (coasts) up to synchronization speed and the main contactor closes.

Various components can affect generator operation, which need to be checked if a generator problem is suspected. They include the wiring between the control box and the generator, the parking brake solenoid, the main contactor and the dynamic brake.

12.3Gearbox

The gearbox is a speed increaser converting the low speed blade rotation to approximately 1500 rpm (50Hz) or 1800 rpm (60Hz). The gearbox is a two-stage planetary gear type and runs with Texaco Pinnacle 150 synthetic oil (normal conditions) or Texaco Pinnacle 68 Synthetic Oil (cold environments).

When investigating gearbox noise, all fasteners on the machine should first be checked for tightness. Noises due the fasteners vibrating have been interpreted as gearbox noise in the past. The oil level in the sight glass should be checked and any oil leaks should be looked for.

Total seizure of the gears causes either the control system to sense a fault or the circuit breakers to open; the blades then no longer move. A failing parking brake exhibits the same symptoms. Conversely, an internal failure can cause the blades to freewheel independently of the drive train.

12.4Blades

The three wood/epoxy laminate or fiberglass composite blades transmit wind energy to the drive train. The blades are attached to the hub, which is held in place on the low speed shaft by a locking ring. The end of each blade is fitted with a tip brake that can be deployed to slow down the rotor, should the parking and dynamic braking systems fail to do so, due to a fault with the gearbox or the dynamic brake capacitors. Minor blade damage can be repaired by epoxying, sanding and painting.

12.5Twist Cable

NOTICE: Use of the material contained in this document is subject to the warning on page Iv and the disclaimer on page v of this document.

DOC012R02

AOC 15/50 User Manual

Nov 2001

Page 108
Image 108
AOC 15 user manual Generator, Gearbox, Blades, Twist Cable