A system for restricting power to a load to prevent engaging a circuit protection device for an electric aircraft includes an energy source. The energy source is communicatively coupled to a load, wherein the load includes a portion of a propulsion system. The system includes sensors configured to sense an electrical parameter. The system includes an aircraft controller communicatively connected to the energy source, wherein the aircraft controller is configured to receive an electrical parameter, compare the electrical parameter to a current allocation threshold, detect that the electrical parameter has reached a current allocation threshold, generate a current allocation threshold notification as a function of the detection, wherein the current allocation threshold notification indicates that the electrical parameter has reached the current allocation threshold.

A trip apparatus has a power terminal, an actuator, a rectifier coupled to the power terminal, a selector, and a processor, the actuator having a pusher member and a coil, the pusher member movable between a first position that does not actuate an actuator interface of a connected circuit breaker and a second position that actuates the actuator interface. The processor has a first input, a second input, and an output, the first input of the processor is coupled to the output of the rectifier, the second input of the processor coupled to an output of the selector, and the output of the processor coupled to the actuator. The processor determines a threshold based on a select signal received at the second input of the processor, and compares a voltage at the first input of the processor to the threshold. The processor controls the coil to selectively control the pusher member in the first or second position based on the comparison of the voltage at the first input of the processor to the threshold.

A trip apparatus has a power terminal, an actuator, a rectifier coupled to the power terminal, a selector, and a processor, the actuator having a pusher member and a coil, the pusher member movable between a first position that does not actuate an actuator interface of a connected circuit breaker and a second position that actuates the actuator interface. The processor has a first input, a second input, and an output, the first input of the processor is coupled to the output of the rectifier, the second input of the processor coupled to an output of the selector, and the output of the processor coupled to the actuator. The processor determines a threshold based on a select signal received at the second input of the processor, and compares a voltage at the first input of the processor to the threshold. The processor controls the coil to selectively control the pusher member in the first or second position based on the comparison of the voltage at the first input of the processor to the threshold.

A band antenna EMP filter apparatus having HEMP protection capability is disclosed. The apparatus includes a discharging part, a band pass filtering part, and a residual current eliminating part. The discharging part primarily discharges a transient voltage due to a high altitude electromagnetic pulse (HEMP) when the HEMP is inputted through an input part receiving a radio frequency (RF) signal of an antenna. The band pass filtering part secondarily blocks a residual current primarily discharged by the discharging part and passes only a signal of a preset frequency band to output it through an output part. The residual current eliminating part limits a transient voltage of the HEMP by eliminating a residual current passing through the band pass filtering part.

A band antenna EMP filter apparatus having HEMP protection capability is disclosed. The apparatus includes a discharging part, a band pass filtering part, and a residual current eliminating part. The discharging part primarily discharges a transient voltage due to a high altitude electromagnetic pulse (HEMP) when the HEMP is inputted through an input part receiving a radio frequency (RF) signal of an antenna. The band pass filtering part secondarily blocks a residual current primarily discharged by the discharging part and passes only a signal of a preset frequency band to output it through an output part. The residual current eliminating part limits a transient voltage of the HEMP by eliminating a residual current passing through the band pass filtering part.

The present disclosure provides a power filter. The power filter may include an overvoltage protection circuit and an LC filter circuit connected to the overvoltage protection circuit, wherein the overvoltage protection circuit includes a voltage regulator and a peak compensation circuit. The peak compensation circuit is configured to generate a gain peak at a resonance frequency of the LC filter circuit, so as to compensate for a gain dip at the voltage regulator stage occurring at the resonance frequency of the LC filter circuit.

In described examples, a circuit includes a reference voltage, a driving circuit with a driving input and a driving output, an output transistor, and a clamp circuit with a clamp input and a clamp output. The output transistor includes a source, a drain, and a gate; the source is coupled to receive the reference voltage. The clamp input is coupled to the driving output and to the gate. The clamp output is coupled to either the driving input or to the driving output, the gate, and the clamp input. The clamp circuit is configured to detect an operating region of the output transistor and to generate a clamping current after the output transistor enters a triode region. The clamping current is selected to prevent an absolute value of a source-gate voltage of the output transistor from equaling or exceeding a gate oxide tunneling voltage of the output transistor.

In described examples, a circuit includes a reference voltage, a driving circuit with a driving input and a driving output, an output transistor, and a clamp circuit with a clamp input and a clamp output. The output transistor includes a source, a drain, and a gate; the source is coupled to receive the reference voltage. The clamp input is coupled to the driving output and to the gate. The clamp output is coupled to either the driving input or to the driving output, the gate, and the clamp input. The clamp circuit is configured to detect an operating region of the output transistor and to generate a clamping current after the output transistor enters a triode region. The clamping current is selected to prevent an absolute value of a source-gate voltage of the output transistor from equaling or exceeding a gate oxide tunneling voltage of the output transistor.

A method for protecting a circuit includes steps of: providing a first current source connected to a capacitor of the circuit through a second switch; providing a detection and control unit for turning on the second switch at a first time, and let the first current source to charge the capacitor; detecting a voltage value of the capacitor by the detection and control unit; wherein when the voltage value is greater than or equal to a reference voltage value, the detection and control unit turns off the second switch and turns on a first switch of the circuit, and when the voltage value is lower than the reference voltage value, the detection and control unit turns off the second switch and continue turns off the first switch.

A power management device and a management method thereof are provided. The power management device includes a switch, a detection circuit and a controller. The switch receives an external power. The detection circuit receives an internal power and at least one operation power. The detection circuit determines whether at least one of the internal power and the operation power is in a preset specification range or not to generate a protection activate signal. The controller sets a protection flag according to the protection activate signal, and generates a control signal according to the protection flag by executing an application program. The controller transmits the control signal to turn off the switch.