晶闸管辅助式有载分接开关的Sen变压器谐波模型OA

To address the difficulty in accurately modeling and uniformly analyzing the complex harmonic characteris-tics of a thyristor-assisted on-load tap changer based Sen transformer under switching and fault conditions,a harmonic model based on an extended T-type equivalent circuit and a state-space method is proposed.First,the electromagnetic coupling relationship among the primary and secondary windings and the excitation branch is characterized based on the extended T-type equivalent circuit,and the thyristor switching and reverse-recovery processes are taken into account to establish a time-domain dynamic model.Then,fast Fourier transform is combined to extract the amplitudes,phase an-gles and total harmonic distortion of individual harmonic components,enabling the unified solution of harmonic respons-es under complex operating conditions.Finally,the proposed model is validated using PSCAD/EMTDC simulations.Re-sults indicate that this model can accurately characterize the harmonic responses under quasi-steady-state,switching and fault conditions,and the harmonic distortion exhibits clear differences among different fault types.Therefore,the model can provide reliable technical support for the unified analysis of harmonic characteristics of the thyristor-assisted on-load tap changer based Sen transformer under complex operating conditions.