Flywheel to recover kinetic energy for hybrid vehicle which has two planetary gears mechanisms for power derivation

摘要

A series-parallel hybrid vehicle which uses two planetary gear mechanisms, the first one (4) dedicated to low vehicle speeds and the second (5) dedicated to high vehicle speeds. The two planetary gear mechanisms include pilot shafts (3rd shafts) which are alternatively coupled to an electric generator (3); output shafts which drive the wheels (9) through a differential (6); and input shafts which receive power from an engine (1). An electrical motor (2) drives the wheels in parallel with the two planetary gear mechanisms. A flywheel (85), less than 1% of the vehicle weight, is coupled to the generator (3) to store kinetic energy of the vehicle during decelerations. The planetary gear mechanisms makes possible higher efficiency at low vehicle speeds where decelerations are frequents. The energy storage performance of the flywheel equals that of ultra-capacitors.;The system provides improvements regarding over torque protection and power-train arrangement.

主权项

1. A power transmitting system for hybrid vehicle comprising:
first and second planetary gear mechanisms for power derivation, each having an input shaft, an output shaft and a pilot shaft, the first planetary gear mechanism (5) having a gear ratio dedicated to high vehicle speeds, the second planetary gear mechanism (4) having a gear ratio dedicated to low vehicle speeds; a selector (7) for choosing one of the first and second planetary gear mechanisms (4) or (5) to be in operation; an electric generator (3), capable of working as a motor, having a rotor coupled to a flywheel (85); an electric motor (2) able to absorb power from the generator (3) and work as a generator; a battery able to absorb or to restitute a balance of electric power from at least one of the electric generator and the electric motor; an engine (1) including an engine shaft; the input shafts of the first and second planetary gear mechanisms (4) and (5) are connected to the engine shaft (1) to receive power; the output shafts of the first and second planetary gear mechanisms (4) and (5) and the electric motor (2) are connected to an axle (6) which drives vehicle wheels;the selector (7) alternatively connects and disconnects each one the pilot shafts of the first and second planetary gear mechanisms (4) and (5) to the generator (3).