Vehicle state information is input, and a control amount, which is control state information, is calculated from the vehicle state information to control a controlled device. A control state is monitored by a monitor unit, and an abnormality is detected based on a state where the vehicle state information or the control state information exists in an abnormality region in which the vehicle state information or the control state information has not reached a failure region corresponding to a failure. The vehicle state information, the control state information, and monitor information are stored in a buffer for a period set in advance while always updating the latest vehicle state information, control state information, and monitor information. When the abnormality is detected, the above respective information before and after the abnormality detection including the information stored in the buffer are stored in a nonvolatile storage unit.

A motor control device includes temperature detection elements that are mounted on a circuit board on which a first power conversion circuit and a second power conversion circuit are mounted and are arranged at a position between the first power conversion circuit and the second power conversion circuit.

Methods for estimation of lost temperature increment after system restart for motor coil temperature estimation in an electric power steering apparatus of a motor vehicle with a power pack including an ECU with a temperature sensor and an electric motor. The methods allow to easily recover the lost heat increment value after restart of the system. Consequently, the estimation of the temperature of the motor coils will start from the correct temperature value. Damage of the motor due to overheat can be prevented. Further a more robust system diagnostics and a more accurate torque signal estimation can be provided.

An electric power steering apparatus that drive-controls a motor by an inverter, and a motor release-switch is connected between the inverter and the motor, comprising: a control section to detect an assist state on a driving control system and to ON/OFF-switch a control of the inverter based on a detection result; a motor rotational number detecting section to detect a rotational number of the motor; an energy calculating section to calculate an energy of a motor back-EMF and a regenerative current based on the rotational number; and a judging section to compare the energy with an area of safety operation of the motor release-switch and to OFF-switch the d motor release-switch when the energy becomes within the area of safety operation. As occasion demands, the area of safety operation is calculated with the temperature.

A motor control unit that is connected to a motor release switch which includes FETs and is disposed between an inverter and a motor, including: a control section to detect an assist state of the inverter, to turn-ON or turn-OFF a control of the inverter based on a detection result and to detect whether abnormality is existed or not; a motor rotational speed detecting section to detect a motor rotational speed; an energy calculating section to calculate an energy based on the motor rotational speed; a judging section to turn-OFF all of the FETs of the motor release switch when the energy is within an area of safety operation; and a state detecting section to detect whether abnormality is existed or not based on information from an abnormality detecting section that detects abnormality of the sensors and the inverter, wherein the control section turns-ON the control of the inverter when the state detecting section does not detect abnormality and turns-OFF the control of the inverter when the state detecting section detects abnormality.

In a rotary electrical machine control apparatus, a selection section selects a relay current limiting value or a coil current limiting value depending on whether a plurality of systems are operated or one or more but not all of the plurality of systems are operated. The system is a combination of a winding set, an inverter, and a power supply relay, which correspond to each other. The relay current limiting value is a current limiting value calculated based on the temperature of the power supply relay. The coil current limiting value is a current limiting value calculated based on the temperature of a choke coil.

A rotary electrical machine control apparatus is provided which controls drive of a rotary electrical machine having a plurality of winding sets. The apparatus includes inverters that are provided so as to respectively correspond to the winding sets, a temperature detection element that detects a base element that is used as a base for estimation of inverter temperatures, which are temperatures of the inverters, and a control section that has a temperature estimation section that estimates the inverter temperatures based on the base temperature and a temperature change amount generated due to current application to the inverters. On-resistance of the switching elements of the first inverter is smaller than on-resistance of the switching elements of the second inverter. The temperature detection element is disposed in an area, a distance between the area and the first inverter being shorter than a distance between the area and the second inverter.

A motor controller includes a temperature estimator that estimates a temperature of an element in a motor driver circuit that drives a motor, or a temperature of a winding of the motor, and a non-volatile memory that provides a first area and a second area for storing the estimated temperature. The temperature estimator writes the estimated temperature to both of the first area and the second area.

A method controls a power-steering assistance of a motor vehicle internal combustion engine that includes an automatic engine stop/restart system and an electric or electrohydraulic power-assisted steering system. The method includes providing, during an automatic engine-stopping phase of the automatic stop/restart system, a steering assistance torque less than an assistance saturation value which is less than a nominal steering assistance value, and maintaining the steering assistance torque during an automatic engine-restart phase.

A self-holding termination determination section has an overheat protection map that defines a relationship between a current value and a maximum temperature of a protected portion to which a current value is applied, and sets a limit temperature corresponding to a required current value at next start time based on the map. The self-holding termination determination section calculates, as an evaluation temperature, temperature obtained by adding a performance assurance upper limit temperature, which assures output performance of a motor at the next start time, to the sum of temperature rises. In a next time performance determination process, if the evaluation temperature for all protected portions has fallen below the limit temperature, the self-holding termination determination section determines that a performance assurance condition is met, and terminates power self-holding based on at least the fact that the performance assurance condition is met.