Predictive current control of voltage-source inverters

A new predictive current controller for a voltage-source inverter is presented in this paper. Practical aspects of realizing the new controller in a system with a digital signal processor (DSP) are considered. Delays introduced by measurements are considered and an improved algorithm with one-period prediction of current is presented. The controller was realized in an experimental system with DSP and field-programmable gate array circuits. Results of the simulations and experiments are presented.

I. Introduction

IN vector-controlled ac motors the first-order component of the inverter output voltage, which is set up by the control system, has an essential meaning. All deviations of this voltage from the reference value have an effect on the quality of the drive performance. These deviations are caused by dead time and by minimum switching times during implementation [12]. The compensation principle of the dead-time effect is well known and used in many systems [9], [11]. However, the problem of minimum switching time of the switches is not well known and needs serious investigation.