Responsive to data indicative of a temperature of a contactor connecting a battery and motor exceeding a threshold, a controller decreases power output from the battery to the motor. The data include parameters indicative of a temperature of the battery, a resistance of an electrical component between the battery and motor, and a thermal resistivity of one or more components other than the battery and motor in a vicinity of the contactor.

A control device, such as a smart thermostat, employs solid state relays as switches to activate and deactivate systems controlled by the device. By measuring the current flow through the power buses to one or more of the solid state relays of the control device, potentially damaging over current conditions can be distinguished from permissible transient over-current conditions and the control device can deactivate any solid state relays which would be damaged while allowing solid state relays which are experiencing allowable transients to remain operating. In the case of a severe over current condition, a current monitoring device can issue a fault signal, triggering an interrupt condition which will cause a processor in the controller to shut down the affected solid state relays very quickly.

An over-temperature protection circuit is described. The circuit comprises an input for sensing a voltage across a transistor, a voltage-to-current converter configured to generate a current in dependence upon the voltage, an accumulator storing a value indicative of power dissipated by the transistor and which depends on the current; and a comparator configured to determine whether the value exceeds a threshold value and, in dependence on the value exceeding the threshold value, to generate a signal to cause the transistor to be switched off.

Examples described herein provide a computer-implemented method that includes monitoring, using a microcontroller, an electric circuit of a vehicle, the electric comprising a battery source and a load. The battery source supplies electric power to the load. The method further includes detecting, using the microcontroller, a high current event in the electric circuit by comparing a current level of a current flowing through the electric circuit to a time-based current threshold. The method further includes responsive to detecting the high current event, controlling a gate driver to cause a switch of an electronically resettable fuse to open the electric circuit to stop the flow of the current through the electric circuit.

The invention relates to a device for operating a voltage converter (1), in particular a DC converter, of a motor vehicle, which voltage converter has at least two parallel-connected converter strands (4, 5) which are connected between a high-voltage side (2) and a low voltage side (3) of the voltage converter (1) for converting the voltage, having at least one cooling device (8) carrying a coolant (9) and assigned to the converter strands (4, 5), wherein each of the converter strands (4, 5) is assigned at least one temperature sensor (6, 7), comprising the following steps: a) detecting an input voltage, an output voltage and an operating current of each converter strand (4, 5), b) detecting a current converter strand temperature by means of the respective temperature sensor (6, 7), c) determining a respective coolant temperature as a function of the values detected in steps a) and b), d) comparing the two determined coolant temperatures (T_1, T_2) with each other and e) determining the serviceability of the temperature sensors (6, 7) on the basis of the result of the comparison.

A system includes a braking resistor and a controllable switch connected in series, the controllable switch adapted to connect to a terminal on a direct-voltage side of an AC/DC converter; an evaluation unit adapted to generate a control signal to control the controllable switch and including a determination device adapted to determine electric power supplied to the braking resistor; a voltage-acquisition device adapted to supply an output signal to the evaluation unit; and a controller adapted to regulate a set value toward an output signal of the determination device, the controller adapted to supply, directly and/or via a limiter, to a parameterizable filter adapted to convey an output signal to a switching element, the switching element adapted to generate an output signal to open and/or close the controllable switch as a function of exceeding and/or undershooting of a threshold value.

The present invention discloses a thermal protection and warning method and system based on junction temperature prediction for a power device of an offshore wind power converter. The method includes: calculating a thermal resistance and a thermal capacitance corresponding to each layer inside the power device, and establishing a corresponding Cauer thermal network model; calculating power consumption at n future moments according to state variables at the n future moments corresponding to a minimized cost function, that is, calculating a variation trajectory of a heat flux parameter; calculating a variation trajectory of a junction temperature of the power device according to the Cauer thermal network model and the variation trajectory of the heat flux parameter; and comparing the calculated variation trajectory of the junction temperature with a warning temperature, and determining a current operating state of the power device.

A thermal monitoring system includes thermal monitoring devices that generate sensor data including thermal images depicting monitored elements (e.g. of an electrical switchgear system). The sensor data for all monitoring devices installed at a local deployment is collected by a gateway device, and relevant data from multiple local deployments is further aggregated by a cloud management system for further analysis. New event triggering rules determining how the thermal monitoring devices filter or record the sensor data are generated based on the aggregated data during a continuous learning process. The system detects patterns in the sensor data for the monitoring devices and/or local deployments as a whole and tracks deviations from these patterns, improving the accuracy of the event detection over time.

A switch device includes a switching element that connects/disconnects a current path from a power supply terminal to a ground terminal via a load, and an overcurrent protection circuit that limits output current flowing in the switching element to be an overcurrent limit value or less. When an output short circuit of the load is detected, the overcurrent protection circuit decreases the overcurrent limit value to be lower as a power supply voltage is higher. In addition, the switch device preferably includes a switching element that connects/disconnects a current path from a power supply terminal to a ground terminal via a load, an intermittent control unit that intermittently drives the switching element when an abnormality is detected, and an output voltage monitoring portion that disables the intermittent control unit until an output voltage applied to the load reaches its target value.

A switch device includes a switching element that connects/disconnects a current path from a power supply terminal to a ground terminal via a load, and an overcurrent protection circuit that limits output current flowing in the switching element to be an overcurrent limit value or less. When an output short circuit of the load is detected, the overcurrent protection circuit decreases the overcurrent limit value to be lower as a power supply voltage is higher. In addition, the switch device preferably includes a switching element that connects/disconnects a current path from a power supply terminal to a ground terminal via a load, an intermittent control unit that intermittently drives the switching element when an abnormality is detected, and an output voltage monitoring portion that disables the intermittent control unit until an output voltage applied to the load reaches its target value.