ABSTRACT
Common auxiliary power (AP), which is also known as station AP, is the power used to drive the auxiliary equipment that is utilized by more than one unit in the entire power station. The running of common auxiliary equipment does not depend on the operation of a particular unit. So, the change in plant load on a particular unit will not directly vary the power used by common auxiliary equipment. The power to this equipment is fed from station transformers (STs). Common AP is subclassified based on voltage level into high tension (HT) AP and low tension (LT) AP; it is also subclassified based on utilities such as the coal-handling plant (CHP), ash-handling plant (AHP), air compressor system, and water treatment plant (WTP). The average total common AP varies between 1.1% and 2.7% of gross generation. The average common AP of a typical 210 MW power plant is about 1.78% of gross power generation (17.4% of total AP). The common (outlying) AP P CAP (MW) is computed as follows: P CAP = ∑ j = 1 j = p ( P ST ) j PL × n × 100 https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9781315371467/69b18755-037e-4db3-b5c5-1c57b9f63490/content/equ4_1.jpg"/>
