Vehicle control apparatus

A vehicle control apparatus to be mounted on a vehicle, the vehicle control apparatus comprising:

• a power supply circuit comprising a first electricity storage device, a second electricity storage device configured to be coupled to the power supply circuit in parallel to the first electricity storage device and having internal resistance that is larger than internal resistance of the first electricity storage device, and a motor generator coupled to the and second electricity storage devices;
• a switch disposed in the power supply circuit and switchable between an electrically conductive state that allows the first electricity storage device to be coupled to the motor generator and a cutoff state that allows the first electricity storage device to be isolated from the motor generator;
• a drive circuit configured to control the switch into the electrically conductive state upon receiving an electric-conduction signal, and configured to control the switch into the cutoff state upon receiving a cutoff signal;
• a battery controller including a first switch controller and a self-diagnostic unit, the first switch controller being configured to transmit the electric-conduction signal or the cutoff signal to the drive circuit, the self-diagnostic unit being configured to detect a malfunction of the first switch controller;
• and
• an engine controller coupled to the battery controller through a communication network and configured to control an engine of the vehicle, the engine controller including a second switch controller configured to transmit the cutoff signal to the drive circuit, wherein
• the battery controller transmits the electric-conduction signal to the drive circuit to control the switch into the electrically conductive state in a case where the motor generator is controlled with charge and discharge of the first electricity storage device, while the battery controller transmits the cutoff signal to the drive circuit to control the switch into the cutoff state from the electrically conductive state in a case where the charge and discharge of the first electricity storage device is stopped to protect the first electricity storage device,
• in a case where the engine controller determines the first switch controller, the self-diagnostic unit, or the communication network as being malfunctioning in accordance with a fail-safe control performed at every predetermined cycle, the engine controller transmits the cutoff signal from the second switch controller to the drive circuit to control the switch into the cutoff state from the electrically conductive state even in a state where the first switch controller transmits the electric-conduction signal to the drive circuit, so that the first electricity storage device is isolated from the motor generator with the second electricity storage device coupled to the motor generator, and
• in the fail-safe control,
• a determination is made as to whether a malfunction signal is received from the self-diagnostic unit, the malfunction signal indicating that the first switch controller is malfunctioning, and when the first switch controller is determined as being malfunctioning with a receipt of the malfunction signal, the switch is controlled into the cutoff state from the electrically conductive state,
• a determination is made as to whether a response signal is received from the self-diagnostic unit after a confirmation signal is transmitted to the self-diagnostic unit, and, when the self-diagnostic unit is determined as being malfunctioning with no receipt of the response signal, the switch is controlled into the cutoff state from the electrically conductive state, and
• a determination is made as to whether the communication network is malfunctioning and, when the communication network is determined as being malfunctioning, the switch is controlled into the cutoff state from the electrically conductive state.