Kawboy wrote: I was curious as to how one would control permanent magnet alternators working in parallel...
Off the top of my head I would think that if you thought you could use 2 regulators with the same part number there could be some extensive surging due to the fact they would both be trying to regulate output voltage simultaneously.
Kawboy, you make two excellent points here.
First, our Kaw alternators are permanent magnet units as compared to automotive alternators, so their methods of regulation are totally different. On a car alternator they control the voltage to the rotor to control the overall output, but on the Kaw regulator they control the output of the alternator windings directly somehow, and it is this "somehow" that I think makes the difference in simply coupling two units together. Looking at the ZN1300's wiring diagram in the supplemental manual, there appears to be a wire between the two regulators that must carry some kind of coordinating signal between the two. Each stator feeds into each regulator directly, but the outputs are paralleled.
Secondly, Kawboy, your point about extensive surging is probably the problem they had on the external alternator trying to work with the built in one on that Wing. Trying to make the two different regulators work together would present a problem, but then add to that the fact that there is no connection between them for coordinating them, and no wonder they failed.
Lucien, the earlier 1300 engines had a crank balancer at one end of the crank and the rotor of the alternator at the other. For the redesign of the ZN1300 engines for the Voyagers, they decided they could add another alternator at the balancer end and use it's rotor for balancing, too! It didn't take much, so that was easy. According to the manuals, the stock KZ's give 28 amps of output and the ZN's give out 45.5 amps. Just a 17.5 amp increase. Not a lot by today's standards. But, driving lights can sure suck up a lot of juice! The headlight alone on a KZ takes up 18% of the output. Add two more of those and you have used more than half of the alternator's total output. OR MORE, depending on what lights you like to use!