ringo wrote:IThe MGUH as stated before is a load and it still doesn't address the problem with back pressure and exhaust mass flow.
What i have learnt from these articles though, is that there are physical limitations to the generator, which caps its output, hence the small gains in fuel efficiency from it.
I don't know why you keep categorizing the MGUH as a load
the existence or non-existence of this conceptual load will be determined by actual MGUH behaviour in use
the MGUH will be the sharp end of a velocity-controlled 'servo' system
that will continuously (ie progressively and powerfully) control the ''turbo' rpm to be always matched to the engine's needs
this matching is crucial and must be dominant by design
the rpm being ideal for the engine, the only MGUH loading of the engine is exactly what the engine 'wants' to do its designed job
the 'turbo rpm' demand will be continuously generated ie appropriately time-varied by part-intelligent control
this appropriate time-variation of rpm constitutes the matching of 'turbo rpm' to the engines time-varying needs and capabilities
the MGUHs essential job is to implement this match (generating/consuming electricity always determined by this match))
seamless and progressively proportionate transition from motoring to generation is what makes a servo-type control system
(a servo drive will always have onboard (capacitive) energy storage for this, it's essential for good control performance)
all servo motors and their drives are MGUs
this means 4 quadrant drive design features (specific to allowing continuous bidirectional drive and bidirectional regeneration)
although we have only unidirectional rotation
there's no significant discontinuities, delays, or deadbands
of course the rpm control could fail to match rpm eg if there is insufficient or excess stored electrical energy
that sort of thing is an issue in what must be a subordinate area of design, it does not invalidate the concept
there's nothing that's 'not to like' about the MGUH control concept, under these rules
these rules were designed by people who knew what they were doing, and knew what they wanted