Line pressure control apparatus and method for vehicle

Abstract

In line pressure control apparatus and method for a vehicle, a line pressure controller outputs a line pressure command to reduce an indicated pressure toward a required indicated pressure by which a required pressure can be secured and which is lower than an initial stage indicated pressure from the initial stage indicated pressure preset to be higher than the required pressure, while a state of each of an electrically driven oil pump (s-O / P) and a mechanical oil pump (M-O / P) enters a first region (a) and outputs the line pressure command to hold the indicated pressure at a time point at which the first region is ended, while the state enters a second region (b), when a hydraulic pressure source is transitioned from the electrically driven oil pump to the mechanical oil pump.

Description

technical field [0001] The present invention relates to a vehicle line pressure (Pressure of Line) control device for generating a line pressure, which is an initial pressure for controlling oil pressure to a hydraulic engagement friction element, based on discharge pressures from two oil pumps. Background technique [0002] At present, in a hybrid vehicle in which the engine, first clutch, motor generator, second clutch (automatic transmission), and driving wheels are connected in series to form a hybrid drive system, both the first clutch and the second clutch are operated by Oil to control the connection and release of the hydraulic clutch. In such a hybrid vehicle, in the EV mode in which the engine is stopped and only the motor generator is used as the power source, the first clutch is released, and in the HEV mode in which the engine and the motor generator are used as the power source, the first clutch is engaged. clutch (for example, refer to Patent Document 1). ...

AI Technical Summary

Problems solved by technology

In this case, when the line pressure drop control is executed, when the coasting control that feedback-controls the clutch pressure is performed so that the second clutch becomes a predetermined differential rotation, the drop of the line pressure command and the feedback of the clutch pressure during the coasting control Interference in the control causes a change in the actual clutch pressure, and as a result, the second clutch pressure fluctuates, causing a chattering feeling.

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