| 摘要 |
A hydraulic control system for distributing pressurized fluid to a multi-mode hybrid-type power transmission is provided, as well as a method for regulating the same. The hydraulic control system includes an engine-driven main pump in fluid communication with a main regulator valve, and an electrically-driven auxiliary pump in fluid communication with an auxiliary regulator valve. One pressure control solenoid provides feedback (boost) pressure to both regulator valves, and thereby modify output of the main and auxiliary pumps. A controller selectively modifies distribution of boost pressure to ensure a continuous and controllable feed of hydraulic pressure to the transmission during all vehicle operations. The method includes: determining if the vehicle is transitioning to engine auto-start or auto-stop; determining the line pressure requirements of the transmission under current operating conditions; starting the oncoming-pump; adjusting PCS command so started oncoming-pump pressure equals line pressure requirements; and shutting down off-going-pump. |
