Harmonic load identification and determination of load composition using a least squares method

Presently, the process of harmonic load identification is limited to identification of one load at a time since it uses measurements of voltage and current at that load bus. Given measurements of the current at any load bus that has one or more loads attached at that bus, this paper addresses two issues. First, a simple method for identifying different types of loads on line is described. Second, a quantitative metric that describes the contribution of each individual load type to the total load at that bus is developed (load composition). A least squares algorithm is then used to perform the task of correctly identifying different load types on line and to obtain a value for the metric that describes the individual contribution of each load type to the total load seen at that bus. This concept of harmonic load identification can naturally be extended to include the case of using substation measurements.