How to Design a Digital AVR for a 208v, 400 hz, 3 Phase Generator

i have a rotary converter generator (208v, 400 hz, 3 phase, 30 kva)

can you lease help me out with a circuit for designing its avr module,

its old avr module has burnt out

previous avr used to take input feedback from all three phases of main winding

and neutral

line voltage = 208v u-v, v-w, w-u

phase voltage =120v u-n, v-n, w-n

the exciter field resistance =129 ohms
the three main windings are healthy and are showing equal ohmic value of 0.3 ohms

with previous avr module following were the exciter field current an exciter field

voltage at no load

exciter field current = approx 0.3 amps

exciter field voltage = approx 36v-38v