A head-mountable device can effectively manage heat with a motor assembly that efficiently and accurately senses a temperature of a motor. A temperature sensor can be provided on an outer surface (e.g., case) of the motor. A flex circuit can be operably connect both the motor and the temperature sensor to a controller of the head-mountable device. The flex circuit can have a first side coupled to the outer surface of the case, a second side supporting the temperature sensor, and thermally conductive vias extending from the first side to the second side to conduct heat from the case to the sensor. The flex circuit can further include a memory comprising calibration data of the temperature sensor and a connector for outputting temperature data based on the temperature sensor and the calibration data of the memory.

A method for predicting a rotor temperature of an electric motor for an electric vehicle. The method includes measuring at least one of an operating parameter of the electric motor; inputting the at least one of the operating parameter of the electric motor into a predetermined regression model to predict a rotor temperature of the electric motor; and communicating the rotor temperature of the electric motor to a vehicle control module for managing the electric motor. The operating parameters includes a measured stator temperature, a torque level output, a rotor speed, and a coolant flowrate of the fixture electric motor. The electric motor may be that of an induction motor.

The invention relates to a device for controlling an alternator of the type that controls a DC voltage (B+A) generated by the alternator (11) according to a predetermined set voltage (U.sub.0) by monitoring the intensity of an energising current (I.sub.EXC) flowing through an energising circuit of the alternator. According to the invention, the device includes a voltage-control loop (7) and a temperature-control loop (17) which comprises a temperature sensor supplying a current temperature (T) of components of the alternator, a subtracter (19) supplying a temperature error (ε.sub.t) between the current temperature (T) and a maximum acceptable temperature (T.sub.max) and a control module (20) supplying a maximum admissible energising percentage (r.sub.max) in accordance with the temperature error according to a predetermined control law.

An arrangement for determining a temperature of an electric machine includes a supply unit for operating the electric machine, with a first temperature of the electric machine computed with a first thermal model of the electric machine in the supply unit, and a computing facility connected to the supply unit by way of a data transmission channel, with a second temperature of the electric machine computed with a second thermal model of the electric machine in the computing facility. The supply unit and the computing facility communicate by way of the data transmission channel so as to enable the computing facility to determine the second temperature of the electric machine with the second thermal model even when no current is supplied to the supply unit.

A temperature estimating apparatus for a synchronous motor comprises: a voltage command generating unit for controlling d-phase current by increasing or decreasing d-phase and q-phase voltages; a voltage acquiring unit for d-phase and q-phase voltages when the d-phase current is varied; a rotating speed detecting unit for the synchronous motor; a current detecting unit for the d-phase and q-phase currents; a winding temperature acquiring unit; a winding resistance converting unit for winding resistance from winding temperature; an inductance calculating unit for d-axis inductance based on the variation of the d-phase current and the q-phase voltage and on the rotating speed; a counter electromotive voltage constant calculating unit from the q-phase voltage, the varied d-phase current, the rotating speed, the q-phase current, the winding resistance, and the d-axis inductance; and a magnet temperature estimating unit for estimating magnet temperature based on the counter electromotive voltage constant.

An arrangement for determining a temperature of an electric machine includes a supply unit for operating the electric machine, with a first temperature of the electric machine computed with a first thermal model of the electric machine in the supply unit, and a computing facility connected to the supply unit by way of a data transmission channel, with a second temperature of the electric machine computed with a second thermal model of the electric machine in the computing facility. The supply unit and the computing facility communicate by way of the data transmission channel so as to enable the computing facility to determine the second temperature of the electric machine with the second thermal model even when no current is supplied to the supply unit.

An apparatus for controlling a drive motor of a vehicle in which a wound rotor synchronous motor is mounted includes: an inverter which controls a stator current supplied to a stator of the drive motor and a rotor current supplied to a rotor of the drive motor; and a drive motor controller which controls the inverter such that the stator current and the rotor current are supplied to the drive motor when a temperature of the rotor is less than a threshold value, and only the stator current is supplied to the drive motor when the temperature of the rotor is greater than or equal to the threshold value.

An apparatus for controlling a drive motor of a vehicle in which a wound rotor synchronous motor is mounted includes: an inverter which controls a stator current supplied to a stator of the drive motor and a rotor current supplied to a rotor of the drive motor; and a drive motor controller which controls the inverter such that the stator current and the rotor current are supplied to the drive motor when a temperature of the rotor is less than a threshold value, and only the stator current is supplied to the drive motor when the temperature of the rotor is greater than or equal to the threshold value.

This invention discloses an Integrated Motor Operation Data Collection and Operation Protection Device. The device is integrated inside of a motor. Its temperature sensors are distributed on windings, slots, lamination, and bearings. The voltage sensing is through the terminal binding posts. The current sensors are clamped on the connections between the terminal binding pasts and windings. The vibration sensor and the on board temperature sensor are integrated on the monitor board. The MCU runs the firmware which performs data collection, data analysis, communication, alarm report and data storage.

A system may include a motor that has a rotor and a stator. The system may include one or more sensors that measure a voltage signal of a winding of the stator. The system may include a processor that executes computer-executable instructions which, when executed, cause the processor to receive, from the one or more sensors, the voltage signal that includes an induced voltage signal associated with the winding of the stator, to determine a time constant associated with the induced voltage signal based on a decay pattern of the induced voltage signal, to determine a temperature of a rotor based on the time constant, and to adjust one or more operations of the motor based on the temperature.