The test results were expected. The vessel undergoing various engine loading, due to manoeuver, affected the performance of the shaft generator which in turn affected the ships service generator. The main engine's governor responded sluggishly, resulting in a slight overspeed of the engine. This in turn affected the shaft generator which began to take more of the main bus load than the service generator. The governor was slow in response, this caused the a slight speed reduction which affected the shaft generator by dropping it's load on the service generator.
Further maneuver provide same results but with more severity.
On the graph, Appendix 01, the 'non essential trip' can twice be observed, and toward the end of the exercise the shaft generator circuit breaker trips, shock loading the service generator. This experiment illustrates the need to keep the shaft generator off the main bus while undergoing engine loading. An example of separate operation of the shaft generator and service generator can be seen in Appendix 03 where the bus tie is not closed. Leduc Copyright 2000 MartinCorp . All rights reserved.