We are going through a quart of oil every 100 to 150 miles.there is no oil stain

At that rate of consumption , you should see some smoke (maybe have someone 'goose' the gas pedal a few times , while you watch the exhaust), or it could be a leak only under 'load' conditions, that is simply blowing off as you move? OR yes , the PCV system(Positive Crankcase Ventilation) system could be at least a partial cause(restricted/blocked off).

If the engine is not leaking the oil, it is eating the oil. Common areas to inspect is the PCV system, a faulty valve can draw more oil vapors from the crankcase than normal. The piston oil control rings can get gummed up causing too much oil to remain on the cylinder walls and will be consumed in the combustion cycle. The intake valve stem seals and the exhaust valve stem seals can also leak too much oil and be consumed in the combustion cycle. Sometimes inspecting the spark plugs can give some indication of how the oil is being consumed.