The Low Duty Centrifugal Compressor Control System and its Impact on the Surge Pressure

This paper presents an analysis of the low duty compressor for marine steam generators and its running conditions. The analysed low duty compressor was observed under three different running zones caused by a throttled flow towards main steam generators. All examples were explained according to real exploitation conditions. As the low duty compressor has the highest influence on the flame stability for the main steam generators while running, it is very important to observe the constant flow towards the main steam generators. Possible flow fluctuation implies instabilities which are explained in the article and the same have to be avoided in order to assure a reliable life span of the low duty compressor and smooth operation of the main steam generators. Furthermore, for preventing efficiency losses of a steam power plant, some methods for avoiding surge effects are emphasized and recommended.