A method for protecting an electric machine of a motor vehicle, In the method, a switch-on frequency for the electric machine is ascertained as a function of operating parameters of the motor vehicle stored in a control unit. The switch-on frequency is compared to a predefinable first threshold value. At least one further threshold value is preset. The electric machine is switched on in the event a control variance exceeds the at least one further threshold value. In the event the switch-on frequency exceeds the first predefinable threshold value, the at least one further threshold value is adapted in such a way that the switch-on frequency of the electric machine is limited.

This three-phase AC motor drive device is provided with: a load; an inverter device 1 for driving the load; an MCOK_A_4 connected between the inverter device 1 and the load and electrically connecting or disconnecting the inverter device 1 to or from the load; a voltage detector 21a having terminals respectively connected to the circuits of at least two phases to detect the voltages between the three phases; and a current detector 11 for detecting the currents of the three phases. In the connection from the inverter device 1 to the load, the inverter device 1, the MCOK_A_4, the voltage detector 21a, the current detector 11, and the load are aligned in this order.

Disclosed are thermal management fluids for electric systems and methods of application. An example thermal management fluid may comprise: a base oil as a major component, wherein the base oil has both of the following enumerated properties: (i) a branch content of about 15 mol. % to about 30 mol. %; and (ii) a naphthene content of about 30 wt. % or less.

A control device includes a control circuit configured to control an inverter circuit that drives a motor by a plurality of switching elements coupled between DC buses, a first power supply system using a voltage source different from the DC buses as a power supply, a second power supply system using the DC buses as a power supply, and a switching circuit configured to switch a power supply system that supplies power to the control circuit from the first power supply system to the second power supply system when an abnormality in the first power supply system is detected. The control circuit continues control of the inverter circuit with a power consumption lower than that before the abnormality is detected in the first power supply system, when the abnormality is detected.

A temperature estimation system and method for an electric motor of a vehicle include a set of sensors configured to measure a set of operating parameters of the electric motor including at least (i) phase current, (ii) speed, and (iii) coolant temperature and a controller configured to access a trained artificial neural network (ANN) temperature estimation model, using the trained ANN temperature estimation model with the set of electric motor operating parameters as inputs, estimate temperatures of a stator and a rotor of the electric motor, and control operation of the electric motor based on the estimated stator and rotor temperatures.

This disclosure describes at least embodiments of an aircraft monitoring system for an electric or hybrid airplane. The aircraft monitoring system can be constructed to enable the electric or hybrid aircraft to pass certification requirements relating to a safety risk analysis. The aircraft monitoring system can have different subsystems for monitoring and alerting of failures of a component, such as a battery pack, a motor controller, and/or a motors. The failures that pose a greater safety risk may be monitored and indicated by one or more subsystems without use of programmable components.

A safety circuit for a high-voltage (HV) electrical system and a HV electrical device are disclosed. The HV electrical system includes one or more one HV electrical devices. Each HV electrical device includes a low-voltage electrical line. A resistor is connected in parallel to the low-voltage electrical line. A controller is connected to the HV electrical device through the low-voltage electrical line.

A system and method of capacitance management in an agricultural vehicle and connected implement, wherein the vehicle and implement have a plurality of electric drives connected to a common connection and connectable to a direct current supply, and each electric drive has an associated Y capacitor between each direct current supply connection and the common connection, wherein the method includes receiving and summing capacitance values for each of the electric drives and comparing with a stored threshold value. If the threshold value is exceeded, a sequence of selective disconnections of individual electric drives is performed until the sum of the received capacitance values is less than or equal to the threshold value. The method may be performed manually, or automatically based on a sequence defined in a priority list until the sum of the received capacitance values is less than or equal to the threshold value.

The invention relates to a method for the external monitoring of a converter (10), the converter (10) being controlled by means of a first electronic control system (12) and the method being implemented by means of a second electronic control system (14) which is independent from the first electronic control system (12). Said method comprises detection (S1) of a current (I) received by the converter (10) and a voltage (U) received by the converter (10) by means of a current/voltage sensor device (16) which is independent from the first electronic control system (12). The invention also relates to a device for monitoring a converter (10), to a computer program product, to a machine-readable storage medium, to a drive train of a motor vehicle, and to a corresponding motor vehicle.

A controller of a drive system is configured to, when a power switch is changed from an on state to an off state in a situation in which it has been diagnosed that an abnormality is occurring in a motor generator, execute a starting check process of checking a drive circuit and an engine starting process of starting an engine. The starting check process includes a voltage reduction process of driving a DC-DC converter until a capacitor voltage becomes lower than or equal to a prescribed voltage. The controller is configured to, on condition that the controller determines through a voltage reduction determination process that the capacitor voltage is reduced as compared to the capacitor voltage at an end of the voltage reduction process, execute the engine starting process.