Applications of real-time simulation techniques for harmonics study of an industrial power system

Due to the increasing use of nonlinear loads, the associated power quality (PQ) problems have become a major concern to many electric utilities and their customers. For efficient and accurate analysis, the performance of computer simulation has been recognized as an important and necessary procedure to the power quality study. With the advanced development of computer and communication technologies, the real-time simulation becomes matured and provides better computational efficiency, flexible and scalable programming, and preserves a preciseness as good as conventional off-line simulation. This paper presents an application example of real-time simulation to harmonics study of an industrial power system. A cluster-based real-time simulator is executed under MATLAB/SIMULINK environment, where an industrial power system including the arc furnace and motor drives, as well as PQ mitigation devices is under test by real-time simulation techniques. In addition, the conventional off-line simulation with variable-step solver is included to compare the performance of the real-time simulation. Results indicate that the real-time simulation has a great advantage in both the computational efficiency and the system size under study than the off-line simulation, while the solution accuracy is maintained.