Fault detection circuit for solid-state motor controllers

A device for circuit protection, comprising:

• one or more switches connected between a power source and a load;
• one or more gate drivers connected to the one or more switches and configured to disconnect the one or more switches based on detecting a fault, wherein the one or more gate drivers are configured to generate a first trip signal indicating a desaturation (DESAT) signal based on an input voltage to the one or more gate drivers and a first trip threshold;
• a current sensor connected to a circuit path to obtain a current flowing through the one or more switches, wherein the current sensor is configured to generate a second trip signal indicating an overcurrent detection (OCD) signal based on the current obtained by the current sensor and a second trip threshold;
• an analog circuit comprising a plurality of operational amplifiers (op-amps), the analog circuit connected between the current sensor and a microcontroller, wherein the analog circuit is configured to generate a third trip signal indicating a transient recompensed instantaneous trip (TRIP) signal based on the current obtained by the current sensor and a third trip threshold adjusted by a rate of change of the current obtained by the current sensor;
• and
• the microcontroller connected to the current sensor, an output end of the analog circuit, and the one or more gate drivers, wherein the microcontroller is configured to generate an output indicating a fault based on the second trip signal and the third trip signal,
• wherein detecting the fault is based on receiving an earlier signal between the first trip signal and the output of the microcontroller, and
• wherein the microcontroller is configured to generate the output of the microcontroller based on receiving an earlier signal between the second trip signal and the third trip signal.

A device for circuit protection, comprising:

• one or more switches connected between a power source and a load;
• one or more gate drivers connected to the one or more switches and configured to disconnect the one or more switches based on detecting a fault, wherein the one or more gate drivers are configured to generate a first trip signal indicating a desaturation (DESAT) signal based on an input voltage to the one or more gate drivers and a first trip threshold;
• a current sensor connected to a circuit path to obtain a current flowing through the one or more switches, wherein the current sensor is configured to generate a second trip signal indicating an overcurrent detection (OCD) signal based on the current obtained by the current sensor and a second trip threshold;
• an analog circuit comprising a plurality of operational amplifiers (op-amps), the analog circuit connected between the current sensor and one or more logic gates, wherein the analog circuit is configured to generate a third trip signal indicating a transient recompensed instantaneous trip (TRIP) signal based on the current obtained by the current sensor and a third trip threshold adjusted by a rate of change of the current obtained by the current sensor;
• and
• the one or more logic gates connected to the current sensor, an output end of the analog circuit, and the one or more gate drivers, wherein the one or more logic gates are configured to generate an output indicating a fault based on the second trip signal and the third trip signal,
• wherein detecting the fault is based on the first trip signal and the output of the one or more logic gates,
• wherein the plurality of op-amps comprises a first op-amp as a differentiator, a second op-amp as an adder, and a third op-amp as a comparator, or
• wherein the plurality of op-amps comprises a first op-amp as a low-pass filter, a second op-amp as a differentiator, a third op-amp as a subtractor, and a fourth op-amp as a comparator.