Abstract: Provided is a redundant system capable of executing a start request received during update of a microcomputer control program even when an external nonvolatile memory is employed in a redundant system in which one load is controlled by a plurality of control circuits having a redundant configuration, the redundant system being low in cost and excellent in responsiveness. In the redundant system that controls one load by a plurality of control systems having a redundant configuration, when an update program signal for the plurality of control systems is received, update of a control program for each of the plurality of control systems in a predetermined order is individually executed, and when a start request of the load is received during the execution of the update of a control program of one predetermined system, the load is controlled by a system other than the one predetermined system, and during the control, the update of the control program of the one predetermined system is continued.

Abstract: The drive controller for the electric motor according to the present invention comprises two drive control systems for two winding sets of the electric motor, each drive control system includes a control circuit, an inverter, a power supply connector and a ground connector, the two control circuits are connected to an internal common ground, each rectifying element that passes a current from the common ground to each ground connector is provided in a line that connects the ground connector and the common ground, each current detection element is provided in a line that connects each positive power supply and a line between the rectifying element and the ground connector, and whether an open fault has occurred in the ground connector is diagnosed based on the voltage that is applied to the current detection element.

Abstract: The drive controller for the electric motor according to the present invention comprises two drive control systems for two winding sets of the electric motor, each drive control system includes a control circuit, an inverter, a power supply connector and a ground connector, the two control circuits are connected to an internal common ground, each rectifying element that passes a current from the common ground to each ground connector is provided in a line that connects the ground connector and the common ground, each current detection element is provided in a line that connects each positive power supply and a line between the rectifying element and the ground connector, and whether an open fault has occurred in the ground connector is diagnosed based on the voltage that is applied to the current detection element.

Abstract: The electronic control unit includes first and second power connectors, first and second ground connectors, first and second inverters, first and second control circuits, and first and second current-voltage conversion elements. Each current-voltage conversion element is provided between a ground of the corresponding first or second inverter and a common ground of the first and second control circuits, and measures a ground current of the corresponding first or second control circuit. Then, each control circuit determines that the corresponding first or second ground connector is in an abnormal state based on a current flowing through the corresponding first or second current-voltage conversion element.

Abstract: The electronic control unit includes first and second power connectors, first and second ground connectors, first and second inverters, first and second control circuits, and first and second current-voltage conversion elements. Each current-voltage conversion element is provided between a ground of the corresponding first or second inverter and a common ground of the first and second control circuits, and measures a ground current of the corresponding first or second control circuit. Then, each control circuit determines that the corresponding first or second ground connector is in an abnormal state based on a current flowing through the corresponding first or second current-voltage conversion element.

Abstract: Control data storage apparatus includes a memory section including a plurality of control data memory blocks to store control data. There is further provided a control section to determine a selected memory block to store control data by selecting from the control data memory blocks.