Average-Value-Based Integrated Induction Machine-Rotor Side Converter System Model in EMTP-type Programs

In this paper, an average-value-based IM-RSC model is proposed based on a modified phase domain machine model and the average-value based converter model. The system conductance matrix for the proposed model becomes constant due to the parameter and space symmetry of the rotor windings, consequently, the simulation efficiency is improved significantly. Besides, the AC- and DC- circuits of the proposed model are decoupled by using one time-step delay to avoid the prediction of rotor voltages. The time-delay can be ignored when using sufficiently small integration time step, while a prediction of electrical variables is applied to enhance accuracy for simulations using large integration time-steps. A study case for DFIG system, which embeds the proposed IM-RSC model, is created in an EMTP-type program, and a same case is built using detailed switch model and qd- induction model in PSCAD. Simulation results compared with PSCAD show that the proposed model maintains good accuracy during both slow and fast transient studies. In addition, it shows more efficient than the detailed models.