Average model of the bootstrap variable inductance (BVI)

The BVI is a recently introduced FACTS controller which can emulate positive and negative inductance. Here it is modelled using an averaging approach, resulting in an equivalent circuit model. Theoretical considerations show that the averaged model should agree well with the original system, and this is confirmed by MATLAB and PSpice simulations. The average model can be improved by adding a switching-ripple approximation, produced by an auxiliary state-space equation. The solution is expandable as a Fourier series which can be suitably truncated. The average-plus-ripple model gives good agreement with the original system