Output power split hybrid electric drive system

A vehicle drive system for a vehicle having a driving engine with an output shaft and at least one set of driven wheels, comprising:

• a planetary gear train coupled to the driving engine output shaft;
• a primary electric machine coupled to said planetary gear train;
• a mechanical differential gearbox coupled between said planetary gear train and each of said driven wheels in said at least one set of driven wheels;
• at least a pair of secondary electric machines, each of said secondary electric machines coupled to one of said driven wheels in said at least one set of driven wheels;
• an electronic controller interposed between said primary electric machine and each of said secondary electric machines, said electronic controller configured to selectively route power between said primary electric machine and at least one of said secondary electric machines to provide mechanical power at a driven wheel associated with said at least one secondary electric machine in a first operational state, and to selectively route power between said primary electric machine and at least one of said secondary electric machines to drive said primary electric machine in a second operational state;
• a mechanical clutch interposed between said mechanical differential gearbox and said planetary gear train;
• a braking system operatively coupled to said planetary gear train;
• wherein said mechanical clutch and braking system cooperate to regulate a flow of mechanical power to said mechanical differential gearbox;
• wherein said planetary gear train and said mechanical differential gearbox define a mechanical power path from said driving engine to said driven wheels;
• and
• wherein said planetary gear train, said primary electric machine, and each of said secondary electric machines define an electrical power path from said driving engine to said driven wheels.