Control device for hybrid vehicle

Abstract

A control device for a hybrid vehicle, comprising a mode whereby the vehicle runs using a motor only, and a mode whereby the vehicle uses both the motor and an engine. When the motor temperature of an MG (2) (300B) exceeds a threshold temperature, an ECU (400) moves from a running mode that uses the MG (2) (300B) only, to a running mode that limits the load on the MG (2) (300B). When the charging state of a battery (310) for running exceeds a threshold value, the ECU (400) performs control such that in addition to the system voltage for driving the MG (2) (300B) being reduced, the threshold temperature is increased, and the running mode whereby only the MG (2) (300B) is used is maintained.

Description

Technical field [0001] The invention relates to a control device for a hybrid vehicle. Background technique [0002] There is known a hybrid vehicle that uses the power of at least one of an engine and an electric motor to travel. In a hybrid vehicle, the power storage amount or state of charge (SC) of the battery that is controlled to supply electric power to the electric motor is within a predetermined range. When the SOC of the battery is below the lower limit of the predetermined range, the engine is forcibly driven, and the battery is charged with electric power obtained by generating power using the driving force of the engine to restore the SOC of the battery. [0003] On the other hand, in hybrid vehicles, in order to improve fuel efficiency, it is required to increase the distance that can be traveled using only the electric motor as much as possible. However, it is known that when the temperature of the electric motor exceeds a predetermined allowable temperature, in ord...

AI Technical Summary

Problems solved by technology

[0008] However, load limiting control that limits the load applied to the motor when the temperature of the motor exceeds a predetermined temperature is effective in protecting the motor. However, if the load on the motor is uniformly limited, there will be The problem that the distance traveled with only electric motors ends up being shortened

For example, when the SOC of the battery that supplies power to the motor is sufficiently high, there is a margin in the power supplied from the battery to the motor, but when the temperature of the motor reaches a predetermined temperature, the control shifts to load limiting control, even though it could have been sufficient. The electric power of the battery is used, but due to the situation on the motor side, it is impossible to maintain the running only by the power of the electric motor, and there is a problem that the electric power of the battery cannot be effectively used

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