I am build a 40KVA permanent magnet generator for diesel engine. the customer request the voltage is DC 28V after an rectifier. may be this 28V dc charge for the battery. can someone help me how much AC voltage should be output by the permanent magnet generator?permanent magnet generator----AC ???V----rectifier---28VDC---charge to battery.
In AC side connect a series high current Choke with less no of turns take the out put use a High current bridge Diodes with suitable heat sink.For regulating out put ,In the series choke place a Dc winding that can be excited by a separate dc circuit, Increase saturation will give same voltage decrease excitation will give drop in voltage.It is like magnetic Amplifier.Set the out put voltage with pre set point or a regulating circuit.I have given rough Idea If you want further detail PM me (This only cheapest method unless you have use thyristor or others to con troll may be expensive)