Abstract:

To solve the problem that a single-stage reduction hub drive system cannot meet the performance specifications of specialized vehicles， and that a two-stage reduction would require the addition of extra control mechanisms， a novel coupled dual motor hub drive system scheme which is composed of two motors， a planetary gear mechanism， and a one-way clutch is proposed in this paper. The system is designed to operate in two coupling modes： torque coupling mode at low speed and speed coupling mode at medium and high speed with an autonomous mode switching capability as a functional requirement. Parameter matching is conducted with the objective of maximizing power utilization rate， and a control strategy for autonomous mode switching is developed. Under the same simulation initial condition， compared to the single motor two speed hub drive system， the coupled dual motor hub drive system exhibits an 81.25% reduction in maximum vehicle speed fluctuation and an 81.58% decrease in maximum acceleration during the mode switching process. An instantaneous optimal control strategy is established. Under the same operating conditions， the coupled dual motor hub drive system demonstrates a 21.42% reduction in energy consumption compared to the single motor two-speed hub drive system. Experimental tests are conducted using a prototype model to further validate the functionality and feasibility of the novel coupled dual motor hub drive system.

Key words: hub drive, coupled dual motor, planetary gear, mode automatic switching