CONTROL SYSTEM FOR HYBRID VEHICLE

摘要

A control system for hybrid vehicles that ensures high motor power while limiting damage on a planetary gear unit is provided. In a planetary gear unit, a sun gear is connected to a first motor, a ring gear is connected to a second motor, and a carrier is connected to an engine. An operating mode of the hybrid vehicle can be selected from a hybrid mode, a single-motor mode, and a dual-motor mode. The control system is configured to shift the operating mode to the hybrid mode if an estimated temperature of the pinion gear is higher than a threshold temperature (step S5), and to the single-motor mode if the estimated temperature of the pinion gear is lower than a threshold temperature (step S7).

主权项

1. A control system for a hybrid vehicle that is applied to a hybrid vehicle comprising:
a prime mover including an engine, a first motor, and a second motor; a planetary gear unit, in which a sun gear is connected to the first motor, a ring gear is connected to the second motor, and a carrier is connected to the engine, in which a driveshaft is connected to the sun gear or the ring gear, and in which a rotation of the carrier is selectively halted by a brake; and a mechanical oil pump that is driven by the engine to deliver oil to the planetary gear unit; wherein an operating mode of the hybrid vehicle is selected from a hybrid mode in which the hybrid vehicle is powered at least by the engine, a first electric vehicle mode in which the hybrid vehicle is powered by the second motor, and a second electric vehicle mode in which the hybrid vehicle is powered by the first motor and the second motor while halting rotation of the carrier by the brake; and wherein the control system comprising a controller that is configured: to estimate a temperature of a pinion gear of the planetary gear unit; to determine an availability of the second electric vehicle mode; to inhibit the second electric vehicle mode if the second electric vehicle mode is unavailable; and to shift the operating mode to the hybrid mode if the estimated temperature of the pinion gear is higher than a threshold temperature, and to the first electric vehicle mode if the estimated temperature of the pinion gear is lower than a threshold temperature.