Applying and comparing the general power theory compensation for unbalance and harmonics

Abstract

The general power theory (GPT) was formulated to provide metering and optimal compensation solutions for practical power delivery systems with unbalance, harmonic distortion, and dc components. Despite the availability of a detailed derivation and description of the GPT, there is still some uncertainty about how to apply it a) in measurement and b) to control a compensator. This paper summarizes the implementation of the GPT and demonstrates its compensation in a power system with equipment generating distortion and unbalance. A model of the physical behavior of a variable speed drive (VSD) and an unbalanced load was developed in MATLAB/Simulink in conjunction with the GPT’s approach to measurement and compensation. The application of the GPT and the results of the modeling indicate that it is possible to achieve optimum compensation for power delivery loss, distortion, and unbalance. A comparison of the novel GPT approach with conventional theory showed the GPT’s better loss reduction and general capability.