Electric Power Quality in Isolated Systems - Requirements and Examples of Analysis

The paper analyses power quality requirements for isolated systems. Standards used within this framework are taken from widely used classification societies rules, international standards applied to shore and off-shore units. The norms can be also divided into merchant and navy ships, both are analyzed. The requirements themselves are just a simple indication tool of the electric power quality. Hence, four real time examples are presented: 1) a navy ship with regular propeller, 2) an all electric ship with power network exceeded 1 MVA, 3) a passenger ship with 6.6 kV network and 4) equipment installed on shore, i.e. 120 kVA uninterruptible power supply system. For some of the presented examples standards are not fulfilled, which is discussed and some remarks are given.