Abstract: A main power supply having a large capacity and a backup power supply having a small capacity are switchable by a power supply switching determination unit in a system. A motor control device drives a motor by the main power supply or the backup power supply. A drive control unit outputs a drive signal, calculated by feedback control of the current detection value with respect to the current command value, to an inverter circuit. When the power supply switching determination unit switches from the main power supply to the backup power supply, the drive control unit moves from a normal control using the main power supply to a backup control that restricts an electric power consumption and prevents the backup power supply from stopping.

Abstract: A power supply system includes a system control unit, an auxiliary power supply, and an auxiliary-power-supply control unit. The system control unit and the auxiliary-power-supply control unit are configured such that information of at least one control unit of the system control unit and the auxiliary-power-supply control unit is able to be output to another control unit of the system control unit and the auxiliary-power-supply control unit. The at least one control unit is configured to output information indicating that an operation of the at least one control unit is stopped to the other control unit when the at least one control unit stops the operation of the at least one control unit.

Abstract: A steer-by-wire steering system includes: a steering device including a steering motor powered by a main power source and/or a backup power source; and a controller configured to control the steering device based on a steering request. When the backup power source is normal, the controller executes an abnormal-situation control based on electric power supplied to the steering motor by the main power source and/or the backup power source when the controller determines that the voltage of the main power source is less than a first threshold. When the backup power source is abnormal, the controller executes the abnormal-situation control based on electric power supplied to the steering motor by the main power source when the controller determines that the voltage of the main power source is less than a second threshold that is greater than the first threshold.

Abstract: A steer-by-wire steering system, including a steering device including a dual-system steering motor including a main system and a sub system, wherein a power supply to the main system is conducted selectively by a main power source and a backup power source, and a power supply to the sub system is conducted by only the main power source, wherein, in a normal power-supply situation in which the power supply to the main system and to the sub system is conducted by the main power source, a controller controls the sub system to operate in accordance with the main system, and wherein, in a backup power-supply situation in which the power supply to the main system is conducted by the backup power source, the controller controls the main system not to operate or to operate while limiting the power supply to the main system and controls the sub system independently.

Abstract: A main power supply having a large capacity and a backup power supply having a small capacity are switchable by a power supply switching determination unit in a system. A motor control device drives a motor by the main power supply or the backup power supply. A drive control unit outputs a drive signal, calculated by feedback control of the current detection value with respect to the current command value, to an inverter circuit. When the power supply switching determination unit switches from the main power supply to the backup power supply, the drive control unit moves from a normal control using the main power supply to a backup control that restricts an electric power consumption and prevents the backup power supply from stopping.

Abstract: A power supply system includes a system control unit, an auxiliary power supply, and an auxiliary-power-supply control unit. The system control unit and the auxiliary-power-supply control unit are configured such that information of at least one control unit of the system control unit and the auxiliary-power-supply control unit is able to be output to another control unit of the system control unit and the auxiliary-power-supply control unit. The at least one control unit is configured to output information indicating that an operation of the at least one control unit is stopped to the other control unit when the at least one control unit stops the operation of the at least one control unit.