A fast harmonic load flow method for industrial distribution systems

A fast harmonic load flow method for industrial distribution systems is presented in this paper. The proposed method is designed to save computational time and to accomplish real-time harmonic analysis. Based on the network structures of distribution systems, current-injection formulation and Kirchhoff's Law, the relationships between the bus voltages, branch currents and harmonic sources can be formulated, and then the fundamental voltage and harmonic voltage for each bus can all be solved by the simple forward/backward sweep techniques. The total harmonic distortion can also be calculated easily. The proposed method is very efficient, since the computational time for the LU decomposition of the Jacobian matrix (or admittance matrix) could be saved. Test results, which are compared with the conventional harmonic load flow method, show that the proposed method is an efficient method and is suitable for real-time harmonic analysis.