The U.S. Department of Energy provides this definition of a line commutated inverter:
An inverter that is tied to a power grid or line. The commutation of power (conversion from direct current to alternating current) is controlled by the power line, so that, if there is a failure in the power grid, the photovoltaic system cannot feed power into the line.
The DOE definition goes the opposite direction (dc to ac) for commutation, suggesting that a synonym for "line commutated inverter" would be "line inverted inverter."
However, all of this to me sounds just like a grid following inverter, that requires an ac grid connection in order to convert dc to ac. Do these two terms mean the same thing, or is there more nuance that I'm missing? Why the use of "commutated" in this odd way?