1.Wuhan University Wuhan 430072 China; 2. Central South University Changsha 410083 China; 3. Hunan University of Science and Technology Xiangtan 411201 China
Abstract The random perturbation of power load can influence the accuracy of load model. By considering the measurement error and random perturbation of power load as an unknown-but-bounded (UBB) error, a load modeling method was proposed based on the Hardy space theory and Carathéodory-Fejér interpolation (CFI). The load model was mapped into linear load model set with prior information in Hardy space. Consistency problem between measured data and model set was formulated to a linear matrix inequality. The feasible solution here was used to construct a high-order transfer function. Simulation results show that when the random perturbation error range from 1%~10%, the output root mean square error（RMSE）is below 0.03, and the model can still match the output well under inaccurate UBB error boundary. The variations of load composition in a certain scale have little effect on model parameters. Simulations using measured data from the phase measurement unit in a power station demonstrate the practicality and validation of the proposed method when exiting UBB error.
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2015, Vol. 30 
