Floating voltages estimation in three-cell converters using a discrete-time Kalman filter

This paper aims at reducing the number of sensors in multicell converters by estimating the capacitor voltages using a load current measurement. To achieve this purpose, we first develop a simple discrete-time model which correctly represents the behavior of the converter in closed loop operation. A discrete Kalman filter (KF) is then detailed for the state estimation in a three-cell converter. Simulation results in the presence of measurement noises are presented to validate this observer. The experimental results for the real-time implementation of the KF are then presented to confirm these simulation results.