Harmonics Assesment at Demand Site Through a 220V Wall Outlet

Abstract

In recent year, non-linear loads, such as televisions, micro-computers and robotic equipments are increasingly connected to the system. These non-linear load inject a large amount of harmonics, especially third, fifth and seventh.Formerly, people just paid attention to the harmonics problem in the high voltage area. However, now a days the effects of harmonics in the distribution system become more significant.Sometimes, the harmonics ratio and the total harmonics distortion exceed the national harmonics standard for the public supply network. For this reason, we need to measure and asses the level of harmonics in the Distribution System. This paper will discuss about harmonics and how to deal with it. It also considers how we assess the harmonics in a distribution feeder. This project used both hardware and software to build the system. The RMS900 from Hathaway is used to record the snapshot data from the line. A computer program,called HAP that is written in MATLAB is used to analyze the data and Modbus protocol make possible the communication the RMS900 and the PC.