Modelling the interaction of multiple small harmonic current sources in an isolated power distribution system

Given the growing number of interactive nonlinear loads in power distribution systems, some techniques to monitor the spread of harmonics through the system need to be developed. This paper examines the nature of harmonics in a naval power distribution system and develops a harmonic model using the CYMHARMO package to monitor current sources and the interaction that can occur in the Canadian Patrol Frigate (CPF) power distribution system. The results indicate that a significant level of harmonics can exist in the CPF system due to 43 identified harmonic current sources. The presence of any capacitive loads will only serve to increase the level of distortion if resonance occurs. With shipboard testing to confirm equipment loading and identify capacitive elements, the model will be a useful tool for naval engineers to examine and modify the CPF system.