Arrangement or mounting of plural diverse prime-movers for mutual or common propulsion, e.g. hybrid propulsion systems comprising electric motors and internal combustion engines {; Control systems therefor, i.e. systems controlling two or more prime movers, or controlling one of these prime movers and any of the transmission, drive or drive units Informative references: mechanical gearings with secondary electric drive [CPC: F16H3/72]; arrangements for handling mechanical energy structurally associated with the dynamo-electric machine [CPC: H02K7/00]; machines comprising structurally interrelated motor and generator parts [CPC: H02K51/00]; dynamo-electric machines not otherwise provided for in [CPC: H02K] see [CPC: H02K99/00]} the prime-movers consisting of electric motors and internal combustion engines, e.g. HEVs characterised by apparatus, components or means specially adapted for HEVs characterised by the assembly or relative disposition of components