Implementation issues of a fuzzy-logic-based three-phase active rectifier employing only Voltage sensors

Switch-mode rectifiers are becoming more and more interesting in those applications where bidirectional power flow, power-factor correction, and electromagnetic interference reduction are required. Typical active rectifiers include current or voltage sensors, however, in order to obtain low-cost systems, their number should be reduced. In this paper, a current-sensorless active rectifier with feedforward fuzzy logic control is presented and discussed. The mathematical description of the system and the design of the fuzzy logic controller are introduced and analyzed; moreover the implementation on a SH7047 microcontroller is presented with emphasis on the most significant implementation issues. Experimental results are reported and discussed.