Control device for hybrid electric vehicle

Abstract

A hybrid electric vehicle is arranged such that a driving force of an electric motor can be transmitted to driving wheels, and a rotary shaft of the motor can be coupled with an output shaft of an engine. When a starting switch is switched from the first to the second position, a start control unit starts power supply from a battery to a power control unit. When the starting switch is switched from the second to the third position, the start control unit starts the engine by the electric motor if a control of the power supply to the electric motor can be executed by the power control unit, and, on the other hand, starts the engine by a starter motor if the control of the power supply to the electric motor is not possible to be executed by the power control unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus, are not limitative of the present invention, and wherein:

FIG. 1 shows a substantial part of a hybrid electric vehicle having a control device according to one embodiment of the present invention;

FIG. 2 shows an inverter and its associated elements in the hybrid electric vehicle of FIG. 1; and

FIG. 3 is a flowchart illustrating start control executed in the hybrid electric vehicle of FIG. 1.

Claims

1. A control device for a hybrid electric vehicle which includes an electric motor and an engine and which is arranged such that a driving force of the electric motor can be transmitted to driving wheels and a rotary shaft of the electric motor can be coupled with an output shaft of the engine, the control device comprising: a battery which stores electric power to be supplied to the electric motor;power control means adapted to be supplied with electric power from the battery, for executing a control of power supply to the electric motor;control judging means for judging whether or not the control of the power supply to the electric motor can be executed by the power control means;a starter motor provided separately from the electric motor and capable of starting the engine by transmitting driving force generated thereby to the output shaft of the engine;a starting switch adapted to be switched to one of at least three positions including first, second and third positions; andstart control means for starting power supply from the battery to the power control means when the starting switch is switched from the first position to the second position, wherein,when the starting switch is switched from the second position to the third position, the start control means causes the power control means to execute the control of the power supply to the electric motor to start the engine by the electric motor if it is judged by the control judging means that the control of the power supply to the electric motor can be executed by the power control means, and, on the other hand, the start control means starts the engine by the starter motor if it is judged by the control judging means that the control of the power supply to the electric motor is not possible to be executed by the power control means.

2. The control device for a hybrid electric vehicle according to claim 1, wherein the power control means includes an inverter circuit for adjusting electric power supplied from the battery to the electric motor, and connection means for connecting the battery and the inverter circuit;the start control means causes the connection means to start connection between the battery and the inverter circuit when the starting switch is switched from the first position to the second position; andwhen the connection between the battery and the inverter circuit by the connection means is completed, the control judging means judges that the control of the power supply to the electric motor can be executed by the power control means.

3. The control device for a hybrid electric vehicle according to claim 2, wherein the connection means includes an inrush current suppression circuit arranged for suppressing an inrush current that flows when the battery is connected to the inverter circuit; andwhen the suppression of the inrush current by the inrush current suppression circuit is finished, the control judging means judges that the control of the power supply to the electric motor can be executed by the power control means.

4. The control device for a hybrid electric vehicle according to claim 1, further comprising confirmation means for providing an indication and/or a notification based on a result of judgment by the control judging means as to whether or not the control of the power supply to the electric motor can be executed by the power control means.