Abstract
The stationary-frame complex-valued frequency-domain modeling has been applied to characterize the frequency-coupling dynamics of three-phase converters. Yet, those models are generally derived through mathematical transformations of the linearized time-invariant models in the rotating dq -frame. A step-by-step modeling method with clear physical insight in the stationary frame is still missing. This article attempts to fill in the void by introducing a general stationary ( αβ )-frame, three-port equivalent circuit model for the converter power stage, based on the direct linearization around time-periodic trajectories. The model not only reveals the frequency-coupling effect of the ac–dc dynamic interaction but also provides an explicit theoretical basis for incorporating the control dynamics. Moreover, the dependence of the frequency-coupling terms on the initial phase of the input voltage is pointed out. Considering the phase-dependent feature, a frequency scan method that can accurately measure the αβ -frame converter model is proposed. The measured frequency responses in both the nonlinear time-domain simulations and experimental tests validate the effectiveness of the frequency scan method and the theoretical analysis.
Original language | English |
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Article number | 8938712 |
Journal | IEEE Journal of Emerging and Selected Topics in Power Electronics |
Volume | 8 |
Issue number | 2 |
Pages (from-to) | 1922-1933 |
Number of pages | 12 |
ISSN | 2168-6777 |
DOIs | |
Publication status | Published - Jun 2020 |
Keywords
- Complex vector
- frequency coupling
- impedance measurement
- phase dependence
- stationary(αβ)-frame model
- voltage-source converter (VSC).