Oversampled dead-beat current controller for voltage source converters

A digital current controller for voltage source converters is presented in this paper that, exploiting a discrete time, internal model of the converter output filter, guarantees a dead-beat type reference tracking dynamic response. It can be considered an example of a novel digital control paradigm that takes full advantage of the currently available high performance digital control hardware, in particular of field programmable gate arrays and large bandwidth analog to digital converters. The controller can be easily specified in any digital hardware description language, synthesized and implemented on a tiny field programmable gate array chip, which guarantees flexibility, high performance and low cost. It is able to achieve wide small signal bandwidth and, exploiting oversampling, almost ideal large signal response. Its intended application areas include both voltage source inverter applications, such as active filters, uninterruptible power supplies, micro-grid distributed energy resource controllers, and DC-DC converter applications, such as interface converters for renewable energy sources, laboratory battery chargers, electronic welding machines.