The design of software phase-locked loop for PWM converters based on fractional integrated controller

Abstract

Three-phase rectifier voltage often use software phase-locked loop, input voltage is appropriate. However, the software phase-locked loop had previously most locks can only perform accurate voltage in order that agreement cannot be done accurately lock in reverse order (lost key). To overcome this drawback in this article combines the principle of phase locked loop voltage argued upon, examined the nature of change of voltage vector angle reverse order, analyze the causes loss of lock reverse order part of a program to design self-adaptive phase locked loop can be done in the correct key sequence voltage and voltage upon reverse order. Also in this article also offer solutions using fractional integrated controller PIX to improve software self-adaptive phase locked loop instead of using the traditional PI controller as the software was designed before. Experimental results have demonstrated the method using fractional controllers to improve software PI phase locked loop three-phase self-adaptive software makes the phase locked loop to work more flexible, done properly locked voltage law in order upon agreement or otherwise. Carry extra one further step, analysis and experiments demonstrated using software adapts phase locked loop can make PWM (pulses width modulation) rectifiers work without influenced by the phase sequence of input voltage.