Question

(a) Explain the advantages and disadvantages of fitting shaft driven generators.

(b) Outline FOUR methods of installation for shaft generators.

Advantages.

Reduced fuel cost. Reduced maintenance. Reduced spare consumption. Can reduce no of diesel generator thus capital cost less. Reduction in space, weight, and noise

Disadvantages.

No direct frequency control

Separate frequency regulator required. [ synchro compensator used to control voltage and frequency]

Method of installation.

Shaft generator positioned directly in line between main engine and propeller.

Large diameter multi-pole shaft length alternator mounted on forward end of main engine.

Coupling alternator to free end of main engine. [HV system]

V – belt driven.

Pneumatic friction type gear

Power taken from free end of main engine.

Chain driven.