Predictive control with efficiency optimization and normalization for a multilevel converter

The good performances of model predictive control for power converters were demonstrated for multi-objective control. A relevant example is the multilevel flying capacitor electronic converter in which both capacitor voltages and output current have to be controlled. Moreover, the efficiency is an essential factor in electrical converter design but few papers focused on it in the control point of view. This paper presents a predictive control scheme for a multilevel converter which minimizes a cost function including a loss related term. The inclusion of a large number of elements into the cost function requires the tuning of many parameters. Normalization of the cost function is introduced in order to help the control designer to choose suitable parameters. Simulation and experimental tests prove that a trade-off between efficiency and accuracy can be achieved by controller adjustment.