Implementation of FPGA based Three Phase Phase-Locked Loop System

A fully digitized hardware design scheme of three phase phase-locked loop controller base on a field pro-grammable gate arrays (FPGA) is presented.This scheme integrated d,q transformation,PI controller,VCO module and other test modules which were all written in Verilog HDL.Simulation results based on Simulink indicate the three-phase PLL controller can lock the phase and frequency within two basic periods.Experimental results verify this controller base on FPGA can provides satisfied dynamic and static performances under aberrant three phase voltage inputs and has min sensi-tive with harmonics and unbalanced voltage caused by the nonlinear load conditions and measurement errors.The controller can satisfy the Flexible AC Transmission System (FACTS) equipments with realtime and accuracy require-ments.