Power system protection device with current limiting and controlled switching functionality for AC and DC applications

Abstract

An arc fault mitigator includes a sensor configured to detect at least one of users in proximity to a power system protection device, light within the power system protection device, and an overcurrent within the power system protection device; a mechanical switching device comprising a fast mechanical circuit interrupter and an actuator; a power electronic circuit coupled in parallel to the mechanical switching device and including a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter configured to interrupt the current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, and a current limiter configured to limit the current from the fast mechanical circuit interrupter to the power electronic circuit. The power electronic circuit interrupter is configured to allow current to pass through within a range of threshold current, and the current limiter is configured to limit the current flowing through the power electronic circuit interrupter; and a controller including a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit.

Description

[0001] Related Applications

[0002] This application claims priority to U.S. Patent Application No. 18 / 220,322, filed July 11, 2023, entitled “POWER SYSTEM PROTECTION DEVICE WITH CURRENT LIMITING AND CONTROLLED SWITCHING FUNCTIONS FOR AC AND DC,” the disclosure of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The disclosed concept relates generally to a power system protection device and method, and more particularly to a power system protection device with current limiting and controlled switching functions in a power distribution system. BACKGROUND

[0004] Switching devices are self-contained, enclosed assemblies that are configured to protect electrical power systems or equipment from short circuit and fault currents and isolate the circuit from the power source during a fault event. Medium voltage (MV) switching devices with a rated voltage of, for example, but not limited to, 4.76 to 38 kV, for AC (alternating current) and / or DC (direct current) applications require fast arc fault mitigation. For MV switching devices, arc energy can be the stress that builds to a limit and can cause an explosion of the switching device in about, for example, but not limited to, ½ cycle (e.g., but not limited to, 8 ms to 10 ms), damaging adjacent switching devices and injuring nearby personnel. A fast ground switch can convert an arc fault into a bolted ground fault by redirecting the arc fault current to ground with a minimum impedance current path in about, for example, but not limited to, 3 ms to 5 ms upon receiving a trip command.

[0005] However, such fast grounding switches are typically designed to be used once and will have to be replaced after operation. Additionally, other devices in the circuit can have to endure fault current until the circuit is interrupted by a circuit breaker, which can take tens of milliseconds, if not longer, causing further damage. Upon receiving a trip command, a fast circuit breaker can interrupt a short circuit in approximately, for example, but not limited to, 30 ms. However, at this point, the gas pressure due to the arc can have already caused damage to the circuit in less than, for example, but not limited to, 10 ms. In some examples, a switch device can include an anti-arc feature with a robust structure, such as, but not limited to, a metal tank, a chimney housing, etc., which is typically provided at the top or back of the switch device, with a tunnel or path to redirect the arc energy. Such anti-arc switch devices are required to withstand a rated arc current for 500 ms and release the arc energy in a specific direction. However, it is very expensive and with a 500 ms withstand capability, the anti-arc switch device and / or devices arranged adjacent thereto can be damaged by a high severity arc. Furthermore, the anti-arc feature needs to be disabled when the switch device is opened during maintenance.

[0006] There is room for improvement in arc fault mitigation in switch devices.

[0007] There is room for improvement in fast interruption of power system protection devices. SUMMARY

[0008] An exemplary embodiment of the disclosed concept provides an arc fault mitigator for a power system protection device. The arc fault mitigator includes a sensor configured to detect at least one of a user in proximity to the power system protection device, a light within the power system protection device, and an overcurrent within the power system protection device; a mechanical switching device including a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter; a power electronic circuit coupled in parallel to the mechanical switching device, the power electronic circuit including a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter coupled to the current commutator and configured to allow current to pass through within a threshold current, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit current flowing through the power electronic circuit interrupter within the threshold current; and a controller coupled to the sensor, mechanical switching device, and power electronic circuit, the controller including a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit based at least in part on a signal from the sensor.

[0009] Another example embodiment provides a power system protection device coupled to a power source and a load. The power system protection device includes a main circuit interrupter, one or more branch circuit interrupters, and an arc fault mitigator. The arc fault mitigator includes a sensor configured to detect at least one of a user in proximity to the power system protection device, a light within the power system protection device, and an overcurrent within the power system protection device; a mechanical switching device including a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter; a power electronic circuit coupled in parallel to the mechanical switching device, the power electronic circuit including a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter coupled to the current commutator and configured to allow the current to pass through within a threshold current range, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit the current flowing through the power electronic circuit interrupter within the threshold current; and a controller coupled to the sensor, the mechanical switching device, and the power electronic circuit, the controller including a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit based at least in part on a signal from the sensor.

[0010] Yet another example embodiment provides a method of mitigating an arc fault. The method includes providing an arc fault mitigator within a power system protection device, wherein the arc fault mitigator includes: (i) a sensor configured to detect at least one of a user in proximity to the power system protection device, light within the power system protection device, and overcurrent within the power system protection device; (ii) a mechanical switching device including a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter; (iii) a power electronic circuit coupled in parallel to the mechanical switching device, the power electronic circuit including a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter coupled to the current commutator and configured to allow current to pass through within a threshold current, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit current flowing through the power electronic circuit interrupter within the threshold current; and (iv) a controller coupled to the sensor, mechanical switching device, and power electronic circuit, the controller including a trip control mechanism configured to control operation of the mechanical switching device and power electronic circuit based at least in part on signals from the sensor; detecting at least one of a user in proximity to the power system protection device, light within the power system protection device, and overcurrent within the power system protection device; and opening the fast mechanical circuit interrupter upon detecting at least one of the user in proximity, or detecting light and / or overcurrent but not detecting the user in proximity and light, and confirming that the overcurrent is an arc fault. BRIEF DESCRIPTION OF DRAWINGS

[0011] A full understanding of the application will be obtained by reading the following description of the preferred embodiments, when taken in connection with the drawings, in which: Figure 1 is a block diagram of an exemplary power distribution system according to a non-limiting embodiment of the disclosed concept; Figure 2 is a block diagram of an exemplary arc fault mitigator according to a non-limiting embodiment of the disclosed concept; Figure 3 shows a block diagram of an exemplary power system protection device according to a non-limiting embodiment of the disclosed concept; and Figure 4 is a method for mitigating an arc fault using an exemplary arc fault mitigator according to a non-limiting embodiment of the disclosed concept. Figure 2 DETAILED DESCRIPTION

[0012] ​Directional phrases used herein, such as left, right, front, back, top, bottom, and their derivatives, refer to the orientation of the elements shown in the figures and are not intended to limit the claims, unless expressly stated herein.

[0013] As used herein, the singular forms of “a,” “an,” and “the” include plural referents unless the context clearly indicates otherwise.

[0014] As used herein, a statement that two or more parts are “coupled” together should mean that these parts are directly or indirectly (i.e., through one or more intermediate parts or components, as long as a link exists) connected together or operating together.

[0015] An exemplary embodiment of the disclosed concept provides an arc fault mitigator that advantageously offers multiple operating modes: (i) an immediate interruption mode upon detection of a user near a power system protection device or upon confirmation that an overcurrent detected within the power system protection device is an arc fault; (ii) a coordinated protection and fault current limiting mode; and (iii) a fault current through mode. The immediate interruption mode limits the arc from developing to a level of damage within a significantly short period (e.g., but not limited to 2 ms) from detection or confirmation. Because the exemplary arc fault mitigator reacts very quickly, it can handle, for example, but not limited to, 0.36 J / cm². 2 The arc energy is much smaller than that required to be handled by conventional power system protection devices that react much slower than this arc fault mitigator. The coordinated protection and fault current limiting mode protects the power electronic circuit breaker by transferring a controlled amount of fault current to it, for example, but not limited to, up to 10 ms. The fault current through mode allows fault current to pass through the power electronic circuit breaker within the threshold current and rated short-circuit duration required by the standard. Furthermore, this exemplary arc fault mitigator can protect power system protection devices in both AC and DC applications. Because it prevents potential damage to power system protection devices from arc faults, it can be reused whenever needed. Moreover, it minimizes the disturbance to the system caused by faults or transient conditions.

[0016] Figure 1 This is a block diagram of an exemplary power distribution system 10 according to a non-limiting exemplary embodiment of the disclosed concepts. The system 10 includes a power system protection device 14 coupled to a power source 12 and a load 16. The power system protection device 14 may be a medium-voltage switchgear or a control device. It may include a main circuit breaker 30 and multiple branch circuit breakers 40 to 43, such as... Figure 3As shown. The power protection system device 14 includes an arc fault mitigator 1, which can be inserted into the existing power protection system device 14 and connects the main circuit breaker 30 to multiple branch circuit breakers 40 to 43. The arc fault mitigator 1 can be a hybrid circuit breaker, which includes a mechanical switching device 100 and a power electronic circuit 200 arranged in parallel with the mechanical switching device 100, such as... Figure 2 As shown. Reference Figures 2 to 4 Arc fault mitigator 1 was discussed in detail.

[0017] Figure 2 This is a block diagram of an exemplary arc fault mitigator 1 according to a non-limiting exemplary embodiment of the disclosed concepts. The arc fault mitigator 1 includes at least a mechanical switching device 100, a power electronic circuit 200, a controller 300, and a sensor 400. The controller 300 is coupled to the mechanical switching device 100 and the power electronic circuit 200. It may be a processing unit including a processor (e.g., but not limited to a controller, microcontroller, etc.) and memory. The controller 300 includes a trip control mechanism 310, such as trip decision logic or algorithm, configured to control the operation of the mechanical switching device 100 and the power electronic circuit 200. The sensor 400 is at least coupled to the controller 300, the mechanical switching device 100, and the power electronic circuit 200, and is configured to detect at least one user near the power system protection device 14, light within the power system protection device 14, and overcurrent within the power system protection device 14. Sensor 400 may include voltage sensors, current sensors, optical sensors configured to detect any light within the power system protection device 14, thermal sensors and / or motion sensors configured to detect users (e.g., but not limited to, field engineers) near the power system protection device 14.

[0018] Mechanical switching device 100 is coupled in parallel to power electronic circuit 200. Mechanical switching device 100 may include a fast mechanical circuit interrupter 110 and an actuator 120. Fast mechanical circuit interrupter 110 may be any mechanical switch, such as, but not limited to, a contactor and / or a pair of contacts encapsulated in a vacuum for rapid switching. Actuator 120 is capable of forcing fast mechanical circuit interrupter 110 to open very quickly, such as, but not limited to, less than 200 μs (hereinafter also referred to as the first time period) from the detection of at least one user, light, or overcurrent. It may be, for example, but not limited to, a Thomson coil-based actuator, which can cause the contacts 110 to open approximately 20 times faster than conventional actuators (e.g., solenoids or springs).

[0019] The power electronic circuit 200 may include a current commutator 210, a current limiter 220, and a power electronic circuit interrupter 230, which operates at least in part based on trip decision logic (i.e., trip control mechanism 310). The current commutator 210 is configured to transfer or commutate current from the fast mechanical circuit interrupter 110 to the power electronic circuit 200 when the fast mechanical circuit interrupter 110 is open. The current commutator 210 may be, for example, but not limited to, a transient commutating current injector. The current limiter 220 is configured to limit the current flowing to the power electronic circuit interrupter 230 within a threshold current. The threshold current depends on the rated current. For example, in the case of providing a continuous current of 2 kA, the threshold current may be set to, for example, but not limited to, 4 kA. The current limiter 220 may be a device or a controlled algorithm that, for example, pulses a device (e.g., but not limited to a motor) at varying rates to limit current during device startup, allowing the device to start slowly without a high inrush current. Therefore, current limiter 220 ensures that excessive current exceeding the threshold current does not flow through power electronic circuit 200. Power electronic circuit interrupter 230 is configured to allow fault current to pass through within the threshold current range. It allows passage for the rated short-circuit duration as required under standards (e.g., but not limited to, IEC discussed below). Power electronic circuit interrupter 230 can be a solid-state switching device, including but not limited to insulated-gate bipolar transistors (IGBTs) and metal oxide varistors (MOVs).

[0020] The advantage of arc fault mitigator 1 is that it is constructed to comply with the international IEC standard for three-phase AC current protection devices. For example, section 5.6 of IEC 62271-100 defines the rated short-time withstand current ( I k That is, the RMS value of the short-circuit current that switching and control equipment can withstand in the closed position during its rated duration under its service conditions. Section 5.7 defines the rated peak withstand current ( I p That is, the peak current associated with the rated short-time withstand current of the first main loop that the switching and control equipment can carry in the closed position under its service conditions. A DC time constant of 45 ms covers most cases and corresponds to a rated peak withstand current equal to 2.5 times the rated short-time withstand current for a rated frequency of 50 Hz. For a rated frequency of 60 Hz, it is equal to 2.6 times the rated short-time withstand current. Section 5.8 defines the rated short-circuit duration (…). t k This refers to the time interval during which switching and control devices can carry a current equal to their rated short-time withstand current in the closed position. The preferred value for the rated short-circuit duration is 1 second.

[0021] Conventional power electronic switching devices (e.g., solid-state switches) can act quickly enough to prevent damage to power system protection devices due to arcing faults, but they cannot withstand the rated short-time withstand current or the rated peak withstand current required by the standard. Conventional mechanical switches may withstand the rated peak withstand current, but may not act quickly enough to prevent damage to power system protection devices. However, as discussed below, the arcing fault mitigator 1 meets all of the rated short-time withstand current, rated peak withstand current, and rated short-circuit duration required by the standard.

[0022] The fast mechanical circuit breaker 110 provides good immediate interruption for the rated short-circuit duration. For example, if sensor 400 detects at least a user (e.g., a field engineer or other person) near the power system protection device 14, the trip control mechanism 310 is configured to disconnect the fast mechanical circuit breaker 110. It immediately (e.g., within a first time period (e.g., but not limited to, 200 μs from detection)) interrupts the current flow through the power system protection device 14. Alternatively, if sensor 400 detects an overcurrent and / or light instead of a user, the trip control mechanism 310 is configured to disconnect the fast mechanical circuit breaker 110 and confirm that the light and / or overcurrent is an arc fault. Upon reaching the first time period (e.g., but not limited to 200 μs), the trip control mechanism 310 is also configured to turn on the current commutator 210 and the power electronic circuit interrupter 230, and upon reaching the second time period (e.g., but not limited to 350 μs), initiate current limiting via the current limiter 220 to determine whether the overcurrent and / or light is an arc fault, and based on the determination that the overcurrent and / or light is an arc fault, disconnect the power electronic circuit interrupter 230 within a third time period (e.g., but not limited to 2 ms). The current limiter 220 begins to limit the current flowing through the power electronic circuit interrupter 230 within a threshold current, so that the power electronic circuit interrupter 230 is not damaged during the passage of the fault current. Therefore, the arc fault mitigator 1 provides immediate protection for people and / or property (just within the rated short-circuit duration) upon detecting an arc fault and / or users near the power system protection device 14.

[0023] Furthermore, the arc fault mitigator 1 is superior to conventional tripping mechanisms in several respects. It offers a novel range of operating modes: (i) an immediate interruption mode, which provides protection for personnel and property and / or limits the arc from developing to a level of damage; (ii) a coordinated protection and fault current limiting mode, which transfers a controlled amount of fault current to the power electronic circuit interrupter 230, thereby protecting the power electronic components therein; and (iii) a fault current through mode, which allows the fault current to pass through the power electronic circuit interrupter 230 within the range of the rated withstand short-circuit current and rated short-circuit duration required by the standard. No conventional tripping mechanism offers such a range of operating modes. Moreover, because the arc fault mitigator 1 reacts so quickly, it only needs to handle, for example, but not limited to, 0.36 J / cm². 2 The arc energy is much smaller than that of conventional power system protection devices. Furthermore, the arc fault mitigator 1 can protect the power system protection device 14 in both AC and DC applications. Because it prevents the power system protection device 14 from potential damage from arc faults, it can be reused whenever needed. In addition, it minimizes interference to the distribution system 10 caused by faults or transient conditions. Furthermore, the arc fault mitigator 1 coordinates with the main controller (not shown) of the power system protection device 14 to handle non-arc fault overcurrents. For example, based on the determination that the detected overcurrent and / or light is not an arc fault, the trip control mechanism 310 is also configured to transfer trip decision control to the main controller of the power system protection device 14. In order to transfer control of the tripping decision, the tripping control mechanism 310 is also configured to turn on the fast mechanical circuit interrupter 110 and turn off the power electronic circuit interrupter 230 within a fourth time period (e.g., but not limited to 10 ms), and transfer control of the tripping decision to the main controller, which can then select an appropriate downstream circuit interrupter to trip and clear the overcurrent.

[0024] Figure 3 An exemplary power system protection device 14' for a power distribution system, based on a non-limiting example implementation of the disclosed concepts, is shown. The power system protection device 14' may be a switching device or a control device, and includes a main circuit interrupter 30, an arc fault mitigator 1', and one or more downstream circuit interrupters 40 to 43. The arc fault mitigator 1' is similar to that described in reference [reference missing]. Figure 1 and Figure 2The arc fault mitigator 1 is described. Therefore, for brevity, some repetitive descriptions can be omitted. The arc fault mitigator 1' can be a hybrid circuit breaker with a fast mechanical circuit interrupter 110, which is arranged in parallel with a current commutator 210, a current limiter 220, and a power electronic circuit interrupter 230. The arc fault mitigator 1' can be located in the main power branch and thus coordinated with all other circuit breakers (e.g., but not limited to upstream and downstream circuit breakers 30, 40 to 43). In some examples, the arc fault mitigator 1' can have a rated voltage of 15 kV AC. It can have a continuous current of 2 kA. It can also have a short-circuit withstand current of 25 kA, a peak withstand current of 65 kA, and / or a breaking current of 10 kA, wherein the instantaneous breaking time is less than or equal to 2 ms. Therefore, the arc fault mitigator 1' readily conforms to the required IEC standards. It will be understood that these values ​​are for illustrative purposes only, and therefore the arc fault mitigator 1' may include different voltage and / or current values ​​where appropriate without departing from the scope of the disclosed concepts. The main circuit breaker 30 may be a main circuit breaker that disconnects the entire power distribution system when a large short-circuit or overload condition is detected. Circuit breakers 40 to 43 may be branch circuit breakers coupled to a specific area or for protection of equipment. It will be understood that this is for illustrative purposes only, and therefore the power system protection device 14' may appropriately include different numbers of circuit breakers within the device without departing from the scope of the disclosed concepts. The power system protection device 14' may include a main controller upstream of the circuit breakers 40 to 43. When the arc fault mitigator 1' detects an overcurrent and / or light that is not an arc fault, the arc fault mitigator 1' may transfer tripping decision control to the main controller, which in turn determines the appropriate circuit breaker to handle the overcurrent.

[0025] Figure 4 The following is shown for use according to the disclosed concept. Figure 2 The arc fault mitigator 1 has a method 4000 for mitigating arc faults. Method 4000 is performed by the controller 300, the trip control mechanism 310, or any other component of the arc fault mitigator 1.

[0026] At 4010, the trip control mechanism determines whether the sensor has detected at least one user near the power system protection device, light within the power system protection device, and overcurrent within the power system protection device. A user can be considered near the power system protection device if they are within 1 meter of it (e.g., but not limited to) or in a power supply room. If the trip control mechanism determines that the sensor has detected at least one user nearby, method 4000 proceeds to 4100. That is, if the trip control mechanism determines that the sensor has detected a nearby user, a user and light, a user and overcurrent, or a user and light and overcurrent, method 4000 proceeds to 4100. If the trip control mechanism determines that the sensor has detected overcurrent and / or light, but no user is nearby, method 4000 proceeds to 4200. If the trip control mechanism determines that no user, overcurrent, or light has been detected, the power system protection device performs normal operation.

[0027] At 4100, the trip control mechanism starts the timer (i.e., sets t=0).

[0028] In 4110, the trip control mechanism disconnects the fast mechanical current interruptor.

[0029] At 4120, the trip control mechanism determines... t Is it greater than or equal to the first time period? The first time period can be, for example, but not limited to, from... t =200 μs from 0. This delay provides sufficient time for the fast mechanical circuit interrupter to fully open. Otherwise, the trip control mechanism waits until t Greater than or equal to the first time period. If so, proceed from method 4000 to 4130.

[0030] At 4130, the trip control mechanism simultaneously activates the current commutator of the arc fault mitigator and the power electronic circuit interrupter.

[0031] At 4140, the trip control mechanism determines... t Whether it is greater than or equal to the fifth time period, for example, but not limited to, from t =0, starting 1.8 ms. If not, the trip control mechanism waits until t The time interval becomes greater than or equal to the fifth time interval. This delay provides the current commutator with sufficient time to switch the current from the fast mechanical circuit interrupter to the power electronic circuit interrupter. If so, method 4000 proceeds to 4150.

[0032] At 4150, the trip control mechanism operates in the third time period (e.g., but not limited to, from...). t Within 2 ms starting from =0, disconnect the power electronic circuit interrupter. Method 4000 then returns to 4010.

[0033] At 4200, the trip control mechanism starts the timer and sets... t =0.

[0034] In 4210, the trip control mechanism disconnects the fast mechanical circuit interrupter.

[0035] At 4220, the trip control mechanism determines whether the timer has reached the first time period (e.g., but not limited to, from...). t =0 (200 μs from start). If not, the trip control mechanism waits until t Greater than or equal to the first time period. If so, proceed from method 4000 to 4230.

[0036] In 4230, the trip control mechanism simultaneously activates the current commutator and the power electronic circuit interrupter.

[0037] At 4240, the trip control mechanism determines... t Whether it is greater than or equal to the second time period, for example, but not limited to, from t =0, 350 μs. If not, the trip control mechanism waits until t Greater than or equal to the second time interval. If so, proceed from method 4000 to 4250.

[0038] At 4250, the trip control mechanism initiates current limiting.

[0039] At 4260, the trip control mechanism determines whether the overcurrent and / or light is an arc fault. If yes, method 4000 proceeds to 4270. If no, method 4000 proceeds to 4280.

[0040] At 4270, the trip control mechanism disconnects the power electronic circuit interrupter during the third time period. Then, method 4000 returns to 4010.

[0041] At 4280, the trip control mechanism activates the fast mechanical circuit interrupter. That is, the trip control mechanism activates the fast mechanical circuit interrupter upon determining that the overcurrent and / or light is not an arc fault, and completes activation within a fourth time period (e.g., but not limited to 10 ms). At 4282, the trip control mechanism deactivates the power electronic circuit interrupter. At 4284, the trip control mechanism transfers trip decision control to the main controller of the power system protection device. The main controller then deactivates the appropriate remote downstream circuit interrupter within a sixth time period (e.g., but not limited to 50 ms) and clears the overcurrent. Then, method 4000 returns to 4010.

[0042] While specific embodiments of the invention have been described in detail, those skilled in the art will understand that various modifications and alternatives to those details can be developed based on the overall teachings of this disclosure. Therefore, the specific arrangements disclosed are intended to be illustrative only and are not intended to limit the scope of the disclosed concepts, which are to be encompassed by the appended claims and any and all of their technical solutions.

Claims

1. An arc fault mitigator for an electrical power system protection device, comprising: a sensor configured to detect at least one of a user in proximity to the electrical power system protection device, a light within the electrical power system protection device, and an overcurrent within the electrical power system protection device; a mechanical switching device including a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter; a power electronic circuit coupled in parallel to the mechanical switching device, the power electronic circuit including a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter coupled to the current commutator and configured to allow current to pass through within a threshold current, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit current flowing through the power electronic circuit interrupter within the threshold current; and a controller coupled to the sensor, the mechanical switching device, and the power electronic circuit, the controller including a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit based at least in part on signals from the sensor. the trip control mechanism is further configured to:

2. The arc fault mitigator of claim 1, wherein, cause the fast mechanical circuit interrupter to open upon detection by the sensor of at least one of the user in proximity to the electrical power system protection device, or cause the fast mechanical circuit interrupter to open upon detection by the sensor of the light and / or the overcurrent but not the user, and determine whether the light and / or the overcurrent is an arc fault. to determine whether the light and / or the overcurrent is an arc fault, the trip control mechanism is further configured to:

3. The arc fault mitigator of claim 1, wherein, cause the current commutator and the power electronic circuit interrupter to close upon reaching a first time period; initiate current limiting via the current limiter upon reaching a second time period; and determine whether the light and / or the overcurrent is an arc fault. based on a determination that the overcurrent and / or the light is an arc fault, the trip control mechanism is further configured to cause the power electronic circuit interrupter to open for a third time period, or wherein, based on a determination that the overcurrent and / or the light is not an arc fault, the trip control mechanism is further configured to transfer trip decision control to a master controller of the electrical power system protection device. to transfer trip decision control, the trip control mechanism is further configured to:

4. The arc fault mitigator of claim 3, wherein, cause the fast mechanical circuit interrupter to close for a fourth time period; 5. The arc fault mitigator of claim 4, wherein, cause the power electronic circuit interrupter to open; and transfer the trip decision control to the master controller of the electrical power system protection device. the first time period comprises 200 μβ, the second time period comprises 350 μβ, the third time period comprises 2 ms, and the fourth time period comprises 10 ms.

2. The arc fault mitigator of claim 1, wherein the sensor is further configured to detect at least one of a user in proximity to the electrical power system protection device, a light within the electrical power system protection device, and an overcurrent within the electrical power system protection device.

6. The arc fault mitigator of claim 5, wherein, 3. The arc fault mitigator of claim 1, wherein the mechanical switching device includes a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter.

4. The arc fault mitigator of claim 1, wherein the power electronic circuit includes a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter coupled to the current commutator and configured to allow current to pass through within a threshold current, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit current flowing through the power electronic circuit interrupter within the threshold current.

5. The arc fault mitigator of claim 1, wherein the controller includes a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit based at least in part on signals from the sensor.

6. The arc fault mitigator of claim 1, wherein the trip control mechanism is further configured to cause the fast mechanical circuit interrupter to open upon detection by the sensor of at least one of the user in proximity to the electrical power system protection device, or cause the fast mechanical circuit interrupter to open upon detection by the sensor of the light and / or the overcurrent but not the user, and determine whether the light and / or the overcurrent is an arc fault.

7. The arc fault mitigator of claim 1, wherein to determine whether the light and / or the overcurrent is an arc fault, the trip control mechanism is further configured to cause the current commutator and the power electronic circuit interrupter to close upon reaching a first time period, initiate current limiting via the current limiter upon reaching a second time period, and determine whether the light and / or the overcurrent is an arc fault.

8. The arc fault mitigator of claim 1, wherein based on a determination that the overcurrent and / or the light is an arc fault, the trip control mechanism is further configured to cause the power electronic circuit interrupter to open for a third time period, or wherein, based on a determination that the overcurrent and / or the light is not an arc fault, the trip control mechanism is further configured to transfer trip decision control to a master controller of the electrical power system protection device.

9. The arc fault mitigator of claim 1, wherein to transfer trip decision control, the trip control mechanism is further configured to cause the fast mechanical circuit interrupter to close for a fourth time period, cause the power electronic circuit interrupter to open, and transfer the trip decision control to the master controller of the electrical power system protection device.

10. The arc fault mitigator of claim 1, wherein the first time period comprises 200 μβ, the second time period comprises 350 μβ, the third time period comprises 2 ms, and the fourth time period comprises 10 ms.

7. The arc fault mitigator of claim 2, wherein, in the event the fast mechanical circuit interrupter is caused to open upon detection of at least one of the users by the sensor, the trip control mechanism is further configured to: cause the current commutator and the power electronic circuit interrupter to close upon reaching a first time period; and cause the power electronic circuit interrupter to open for a third time period.

8. The arc fault mitigator of claim 1, wherein, the arc fault mitigator satisfies all current short circuit withstand requirements including a rated short time withstand current, a rated peak withstand current, and a rated short circuit duration.

9. A power system protection device coupled to a power source and a load, comprising: a main circuit interrupter; one or more branch circuit interrupters; an arc fault mitigator coupled downstream of the main circuit interrupter and upstream of the one or more branch circuit interrupters, the arc fault mitigator comprising: a sensor configured to detect at least one of a user in proximity to the power system protection device, a light within the power system protection device, and an overcurrent within the power system protection device; a mechanical switching device comprising a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter; a power electronic circuit coupled in parallel to the mechanical switching device, the power electronic circuit comprising a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit upon opening of the fast mechanical circuit interrupter, a power electronic circuit interrupter coupled to the current commutator and configured to allow current to pass therethrough within a threshold current, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit current flowing through the power electronic circuit interrupter to within the threshold current; and a controller coupled to the sensor, the mechanical switching device, and the power electronic circuit, the controller comprising a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit based at least in part on signals from the sensor.

10. A method of mitigating an arc fault, comprising: An arc fault mitigation device is provided within a power system protection device, wherein the arc fault mitigation device includes: (i) a sensor configured to detect at least one of a user in proximity to the power system protection device, light within the power system protection device, and overcurrent within the power system protection device; (ii) a mechanical switching device including a fast mechanical circuit interrupter and an actuator configured to actuate the fast mechanical circuit interrupter; (iii) a power electronic circuit coupled in parallel to the mechanical switching device, the power electronic circuit including a current commutator configured to commutate current from the fast mechanical circuit interrupter to the power electronic circuit when the fast mechanical circuit interrupter is open, a power electronic circuit interrupter coupled to the current commutator and configured to allow current to pass through within a threshold current, and a current limiter coupled to the current commutator and the power electronic circuit interrupter, the current limiter configured to limit current flowing through the power electronic circuit interrupter within the threshold current; and (iv) a controller coupled to the sensor, the mechanical switching device, and the power electronic circuit, the controller including a trip control mechanism configured to control operation of the mechanical switching device and the power electronic circuit based at least in part on a signal from the sensor; detecting at least one of a user in proximity to the power system protection device, light within the power system protection device, and overcurrent within the power system protection device; and upon detecting at least one of the user in proximity, opening the fast mechanical circuit interrupter, or upon detecting the light and / or the overcurrent but not detecting the user in proximity, opening the fast mechanical circuit interrupter, and confirming that the light and / or the overcurrent is an arc fault.

11. The method of claim 10, wherein, confirming that the light and / or the overcurrent is an arc fault includes: upon reaching a first time period, simultaneously closing the current commutator and the power electronic circuit interrupter; upon reaching a second time period, initiating current limiting via the current limiter; and determining whether the light and / or the overcurrent is an arc fault.

12. The method of claim 10, wherein, confirming that the light and / or the overcurrent is an arc fault further includes: based on determining that the light and / or the overcurrent is an arc fault, opening the power electronic circuit interrupter for a third time period, or based on determining that the light and / or the overcurrent is not an arc fault, transferring trip decision control to a master controller of the power system protection device.

13. The method of claim 12, wherein, transferring trip decision control to a master controller of the power system protection device includes: closing the fast mechanical circuit interrupter for a fourth time period; opening the power electronic circuit interrupter; and transferring the trip decision control to the master controller of the power system protection device.

14. The method of claim 13, wherein, The first time period comprises 200 μs, the second time period comprises 350 μs, the third time period comprises 2 ms, and the fourth time period comprises 10 ms.

15. The method of claim 14, further comprising: after turning off the fast mechanical circuit interrupter upon detecting at least one of the users in the vicinity, turning on the current commutator and the power electronic circuit interrupter simultaneously upon reaching a first time period; and turning off the power electronic circuit interrupter within a third time period.

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