It amounts to the fact that they arenít needed. The only advantage a variable speed compressor
would give is that it could run continuously varying speed to control the amount of cooling
necessary as opposed to the current
on and off system.
Very similar thing in Inverter
generators, why arenít larger generators inverter generators and take advantage of the variable speed? Well Iíve asked that question only to be told there isnít any advantage once you get beyond small generators, that Diesels in particular donít use much less fuel
at lower RPM
I can infer that a variable speed compressor
for air conditioning
wouldnít add much that one that shuts off and on does.
One thing I really liked about our Toyota Prius is the airconditioner, being electric
itís output wasnít tied to engine RPM
, and Iím almost certain itís a variable speed compressor by using a brushless DC motor
Now what confuses most people is that a brushless DC motor
like our refrigerators are actually AC motors. A brushless DC motor is lighter, lasts longer and is more efficient than a brushed DC motor or an AC motor.
But Iím not sure how one would be run from AC power, it is first converted back to DC, to just then be converted to variable frequency AC again? Or would it take AC at a set frequency and then convert the frequency to drive motor speed?