JC refrigeration AC or DC upgrade?
Just wondering if any of you could tell me whether I should buy the AC or DC conversion for my dometic rm2652. We are on shore power almost always except for traveling. Would the truck charge batt...
Forum Discussion
NRALIFR wrote:
Yeah, that would have to be a very special inverter to produce 3-phase AC from 12v DC. The curiosity in me wonders how they do it. I’m familiar with rotary and static AC phase converters, but not DC.
It's not much different than a single phase inverter--there are just three sets of output transistors rather than one set. In either case, you have a DC-DC converter that produces high voltage DC rails, and then some output devices--likely MOSFETs or IGBTs--that switch them to produce an AC waveform. For an MSW inverter, these are just switched on and off per cycle to make a sort of squared off waveform; for a PSW inverter, they would be synthesizing a sine wave using a PWM drive circuit (and perhaps a simple filter circuit).
Brushless DC motors use basically the same sort of technology, just not always with a higher voltage supply. It's entirely possible that the compressor is using a brushless DC motor rather than a three phase induction motor; either one would be quite practical for the application.
