Extended Newton–Raphson Algorithm for Accurate Power-Flow Calculation of Industrial Facilities Based on Induction Motor Catalog Information

Abstract

An accurate operating point is crucial when planning and operating industrial process plants that have numerous induction motor loads. Most commercial software tools currently adopt a static PQ load model for power-flow studies, which doesn’t fully capture the true active and reactive demands of the induction motors. Integrating the motor’s equivalent circuits into the power-flow algorithm can resolve this issue. However, the required data for a set of motor’s equivalent-circuit parameters is often unavailable for such studies. Additionally, directly measuring or identifying the parameters of all installed motors in the plant is neither cost-effective nor efficient. To address this limitation, this paper presents a comprehensive unified power-flow computational technique that allows for straightforward determination of the exact operating condition of induction motors using readily available catalog information. To achieve this objective, Kloss’s formulas of single-cage induction motors are further developed to formulate the mismatch function of the Newton–Raphson method. The extended algorithm and Kloss’s equations are thoroughly validated. Good agreements with acceptable accuracy are observed in a satisfactory manner.