Deadtime Compensation for Model Predictive Control of Power Inverters

When employed as a modulator in power inverters, model predictive control has an equivalence to a recently proposed modulation technique known as feedback quantizer modulation (FBQM). Both schemes produce a random-like switching pattern that can facilitate explicit control over the shape of frequency spectra associated with inverter output voltages and currents. This is useful to satisfy electromagnetic interference and acoustic noise requirements, and to avoid excitation of external system resonances. However, it will be shown in this paper that inverter deadtime introduces a disturbance into FBQM that significantly degrades the ability to shape the frequency spectra. Several compensation techniques, designed to model the effect of deadtime inside the formulation of FBQM, are proposed and experimentally verified on a two-level three-phase inverter.