The invention discloses a 
digital control device for three-phase AC 
voltage regulation. The primary side of a three-phase 
transformer is connected to a three-phase 
AC power supply, and the 
secondary side is electrically connected to a zero-crossing detection module and a three-phase 
rectifier circuit; the zero-crossing detection module, 
data acquisition  The output ends of the modules are respectively connected to the host computer, and the host computer controls the three-phase rectification circuit through the pulse trigger module; the invention also discloses a 
digital control method for three-phase AC 
voltage regulation: the 
data acquisition module collects the measured 
voltage signal and the measured current of the load  
signal, the upper computer calculates the deviation between the measured voltage 
signal and the given voltage signal, and obtains the current control amount through 
voltage loop adjustment control; calculates the deviation between the current control amount and the measured current signal, and obtains the 
voltage control amount through current adjustment control, and the upper computer refers to  The zero-crossing pulse signal output by the zero detection module enables the pulse trigger module to output a pulse signal to control the three-phase rectification circuit to realize three-phase AC 
voltage regulation.  The invention has the characteristics of precise zero-crossing detection, stable triggering and the like.