Asymmetric Dynamic Modeling and Parameter Evaluation of Complex Load Model for Power System Stability Analysis

Due to their crucial impacts on the stability of the power system and their significant power demand, industrial loads, with their symmetrical and asymmetrical properties, have been gaining more recognition in the composite load modeling field. The established composite load model, known as the complex load (CLOD) model and used in commercial simulators (Power System Simulation for Engineering (PSS®E) and PowerWorld Simulator), has been used to represent composite loads efficiently. This model has a limited number of parameters combined with high accuracy. In the literature, the mathematical representation of this model is incomplete due to the complexity of some components of this model. This paper proposes a detailed mathematical representation of the CLOD model to enhance its capability and efficiency in capturing the dynamic response. Heuristic and regression techniques are utilized to estimate and tune the parameters of the proposed model. Compared with existing composite models, the proposed model requires a minimum set of parameters and low computational demand while ensuring accuracy with ease of implementation in large-scale industrial circuits. For model verifications, the output of the proposed model is compared with the output from the PSS®E model under different symmetric and asymmetric load distribution structures representing common customer classes, including residential, commercial, and industrial loads.