Improvement and Implementation of One Phase Power Phase-locked Loop based on FPGA

A control scheme for one phase Phase-Locked Loop(PLL) and the way for implementing it on a Field Pro-grammable Gate Arrays(FPGA) were presented according to one phase power supply applications.The schemes consists of cycle integrator,PI controller,sinus and cosine module and other control module were written in verilog Hardware De-scription Language(HDL).Results of software analysis indicated the control scheme can lock the basic phase of power net fast,and has a minimum sensitivity to harmonics.Experiments based on FPGA proved the perfect performance.The funda-mental phase can be locked well when the input distorted seriously and the phase can be locked again fast when the input phase changed suddenly.The controller can satisfy the Flexible AC Transmission System(FACTS) equipments with accu-racy requirements.