Patent ID: 7561949

Claim:
A split series-parallel hybrid dual-power drive system operable alternatively as a series power drive system or a parallel power drive system comprising: a first drive system for driving a first load, the first drive system including an engine and a first dynamo-electric unit, the engine having a rotary part coupled to the first dynamo-electric unit directly or through a first transmission unit; a second drive system for driving a second load; the second drive system including a second dynamo-electric unit, the second load being couple to the second dynamo-electric unit directly or through a second transmission unit; a second clutch provided between and coupled to the first dynamo-electric unit and the first load; a rechargeable device coupled to at least one of the first and second dynamo-electric units, the rechargeable device being rechargeable, when driven by the engine and a first load is a light load that is less than a normal load, by power from the first dynamo-electric unit, the rechargeable device driving at least one of the first and second dynamo-electric units to function as a motor when driven by the engine and the first load is a heavy load that is more than the normal load; and a drive control unit for controlling the first drive system, the second drive system, the second clutch, and the rechargeable device; wherein when the system operates as the series power drive system, the second clutch is disengaged, so that the engine runs at lower fuel consumption with higher fuel saving so as to reach brake specific fuel consumption, and at this time an electric power from the first dynamo-electric unit drives the second dynamo-electric unit via the control unit to drive the second load.