Arc fault detection system, method and storage subsystem

Abstract

An arc fault detection system, method, and storage subsystem are disclosed. The arc fault detection system includes a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of the power distribution system and an arc fault detector electrically connected to the plurality of capacitive arc fault sensors. Each capacitive arc fault sensor is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with the arc. The arc fault detector is configured to receive one or more arc fault signals from one or more of the plurality of capacitive arc fault sensors, and determine a location of an arc fault in the power distribution system based at least on the one or more arc fault signals.

Description

Technical Field

[0001] The present disclosure relates generally to the field of electronics, and more particularly to a high voltage power distribution system for an electrified airborne platform. Background Art

[0002] Conventional power distribution systems typically monitor for short circuit, overcurrent, and / or undervoltage conditions and perform mitigation operations based on the detection of such conditions. However, conventional power distribution systems are not capable of detecting arc faults. An arc fault occurs when an electrical discharge occurs between two or more conductors in an electrical system. This discharge generates heat that can cause degradation of various components in the electrical system. Lacking the ability to detect arc faults, conventional power distribution systems are susceptible to degradation when an arc fault occurs. Summary of the invention

[0003] An arc fault detection system is disclosed. The arc fault detection system includes a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of a power distribution system and an arc fault detector electrically connected to the plurality of capacitive arc fault sensors. Each capacitive arc fault sensor is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc. The arc fault detector is configured to receive one or more arc fault signals from one or more of the plurality of capacitive arc fault sensors and determine a location of an arc fault in the power distribution system based at least on the one or more arc fault signals.

[0004] The features and functions that have been discussed can be achieved independently in various embodiments or may be combined in yet other embodiments, further details of which can be seen with reference to the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 An exemplary embodiment of an aircraft including a power distribution system is schematically illustrated.

[0006] Figure 2 An exemplary embodiment of an arc fault detection system for an electric power distribution system including an electric motor is schematically illustrated.

[0007] Figure 3 Another exemplary embodiment of an arc fault detection system for an electric power distribution system including a plurality of electric motors is schematically illustrated.

[0008] Figure 4 The present invention shows a method including a capacitor arc fault sensor responsive to different Figure 3 An example table of arc fault signal amplitudes generated by an arc fault occurring in an electric power distribution system is shown in FIG.

[0009] Figure 5 An exemplary embodiment of a capacitive arc fault sensor is schematically illustrated.

[0010] Figure 6 An exemplary implementation of an arc fault detection method is shown.

[0011] Figure 7 An exemplary implementation of a computing system is shown. DETAILED DESCRIPTION

[0012] Detecting and locating arc faults in power distribution systems presents various challenges. As an example, low-intensity arc faults (such as series arc faults) produce a relatively small voltage drop (e.g., less than tens of volts), which may be difficult to detect under high voltage operating conditions where the operating voltage level (e.g., hundreds of volts) is significantly greater than the relatively small voltage drop. As another example, in a configuration where the power distribution system includes a power source in the form of a battery, the normal operating voltage envelope may vary by up to 100% (e.g., from 800 V when the battery is fully charged to 400 V when the battery is discharged). Due to the dynamic changes in the voltage of the power source during the entire operation of the power distribution system, the relatively large operating voltage envelope makes the common mode measurement of the voltage caused by the arc fault challenging. As yet another example, in a configuration where the power distribution system includes one or more motors controlled by one or more corresponding motor controllers, the voltage ripple from the motor controller can reach substantial values ​​(e.g., as high as the system voltage itself). In addition, the power distribution system typically includes cables that act as attenuators of the ripple voltage, which makes differential protection an inefficient measurement method for detecting arc faults.

[0013] This challenge is exacerbated in high voltage power distribution systems, such as the high voltage direct current (HVDC) power distribution systems employed in all-electric or hybrid aircraft. The reliability of the power distribution system plays a critical role in the operation of all-electric or hybrid aircraft. The ability to detect and mitigate arc faults increases the reliability of the power distribution system in an all-electric or hybrid aircraft relative to systems that lack the ability to detect arc faults.

[0014] Therefore, to address the challenges discussed above and other challenges, the present specification is directed to an arc fault detection system. In one example, the arc fault detection system includes a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of a power distribution system and an arc fault detector electrically connected to the plurality of capacitive arc fault sensors. Each capacitive arc fault sensor is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc. The arc fault detector is configured to receive one or more arc fault signals from one or more of the plurality of capacitive arc fault sensors, and determine a location of an arc fault in the power distribution system based at least on the one or more arc fault signals.

[0015] The arc fault detection system provides various technical benefits. For example, each capacitive arc fault sensor is configured to detect arc fault characteristics in the form of high frequency voltage distortion (e.g., frequencies exceeding 10 MHz and extending to the GHz range) generated by capacitive coupling with the arc. By monitoring arc faults in the high frequency spectrum, the capacitive arc fault sensor is able to reliably detect arc faults even when the voltage distortion is relatively small. As another example, by detecting arc faults based on capacitive coupling, common mode measurements that may be unreliable due to the large operating voltage envelope of the power distribution system can be avoided. As another example, since the capacitive arc fault sensor detects arc faults based on capacitive coupling, the capacitive arc fault sensor does not need to be in direct physical contact with the conductor of the section being monitored by the capacitive arc fault sensor. Since the capacitive arc fault sensor is not in direct physical contact with the corresponding conductor of the section being monitored, high voltage / current is prevented from passing through the capacitive arc fault sensor to reach the arc fault detector and thereby causing degradation of the arc fault detector or other circuits. As another example, when a plurality of capacitive arc fault sensors transmit arc fault signals indicative of an arc fault to an arc fault detector, the arc fault detector can analyze the arrival time, phase, and amplitude of the arc fault signals to accurately determine the location of the arc fault in the power distribution system. The arc fault detection system can be particularly beneficial in all-electric / hybrid electric aircraft applications to improve the robustness of an electric power system that relies on power for propulsion of the aircraft.

[0016] Figure 1An exemplary embodiment of an aircraft 100 including a HVDC power distribution system 102 is schematically illustrated. The HVDC power distribution system 102 is located in a fuselage 104 of the aircraft 100. The HVDC power distribution system 102 is configured to draw power from a DC power source in the form of a battery subsystem 106. The HVDC power distribution system 102 includes a power distribution panel (PDP) 108 configured to distribute power from the battery subsystem 106 to two parallel loads in the form of a pair of motor controllers 110A, 110B that are electrically connected to a corresponding pair of propulsion motors 112A, 112B.

[0017] The arc fault detection system 114 is configured to monitor the operation of the HVDC power distribution system 102 to detect and locate the arc fault when it occurs. The arc fault detection system 114 includes a plurality of capacitive arc fault sensors 116A, 116B, 116C, 116D electrically connected to a plurality of different sections of the HVDC power distribution system 102. More specifically, the first capacitive arc fault sensor 116A is electrically connected to the terminals of the battery subsystem 106 and monitors the section between the battery subsystem 106 and the PDP 108, the second capacitive arc fault sensor 116B is electrically connected to the terminals of the PDP 108 and monitors the section connected to the PDP 108, the third capacitive arc fault sensor 116C monitors the section between the PDP 108 and the first motor controller 110A, and the fourth capacitive arc fault sensor 116D monitors the section between the PDP 108 and the second motor controller 110B.

[0018] The arc fault detector 118 is electrically connected to each of the plurality of capacitive arc fault sensors 116A, 116B, 116C, 116D. Each capacitive arc fault sensor is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with the arc. In one example, the high frequency current refers to a current having a frequency of, for example, 10 MHz and extending to the GHz range. The arc fault detector 118 is configured to receive one or more arc fault signals from one or more capacitive arc fault sensors and determine the location of the arc fault in the power distribution system 102 based at least on the one or more arc fault signals. In some cases, the arc fault detector 118 receives a plurality of arc fault signals from the plurality of capacitive arc fault sensors 116A, 116B, 116C, 116D, and the arc fault detector 118 is configured to determine the location of the arc fault based at least on the difference in amplitude of the plurality of arc fault signals, the arrival time, and / or the difference in phase of the plurality of arc fault signals, as will be described in further detail below.

[0019] Although arc fault detection system 114 is described herein with reference to aircraft HVDC power distribution applications, this is by no means limiting. The disclosed arc fault detection system may be used in other applications, including HVAC power distribution, non-aircraft vehicle applications, and non-vehicle applications.

[0020] Figure 2 An exemplary embodiment of an arc fault detection system 200 for an electric power distribution system 202 is schematically illustrated. The electric power distribution system 202 includes an electric motor 204 electrically connected to a motor controller 206. The motor controller 206 is electrically connected to a DC power source 208.

[0021] The motor controller 206 is configured to modulate the power received from the DC power supply 208 to control the speed and / or torque of the motor 204. More specifically, the motor controller 206 is configured to receive control signals from an external source (not shown), such as a microcontroller or a manual control interface (e.g., a joystick, a throttle, or a button). These control signals indicate the desired speed and torque of the motor 204. The motor controller 206 is configured to process the control signals using a control algorithm to determine the appropriate output to the motor 204. For example, the control algorithm may involve a feedback mechanism such as a proportional-integral-derivative (PID) control for precise speed and position control. The motor controller 206 is configured to modulate the voltage and / or current supplied to the motor 204 based on the output of the control algorithm. The motor controller 206 may use various techniques to modulate the power supplied to the motor 204, such as pulse width modulation (PWM). The motor controller 206 is configured to send the modulated power to the motor 204, and the motor 204 adjusts the speed and / or torque based on the modulated power to provide the desired motor output.

[0022] In some embodiments, the motor 204 is an alternating current (AC) motor 204, and the motor controller 206 is configured to convert DC power received from the DC power source 208 to AC power suitable for controlling the operation of the AC motor 204. In other embodiments, the motor 204 can be a DC motor 204, and the motor controller 206 can be configured to output DC power to the DC motor 204.

[0023] The arc fault detection system 200 is configured to monitor the operation of the power distribution system 202 to detect and locate arc faults when they occur. The arc fault detection system 200 includes a plurality of capacitive arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F electrically connected to different sections 212A, 212B of the power distribution system 202. As used herein, sections of the power distribution system refer to different electrical connections (e.g., cables, wires, connectors, tracks) between electronic components of the power distribution system.

[0024] In the illustrated embodiment, a first capacitive arc fault sensor 210A is electrically connected to the first segment 212A at a positive output terminal of the DC power source 208. A second capacitive arc fault sensor 210B is electrically connected to the second segment 212B at a negative output terminal of the DC power source 208. A third capacitive arc fault sensor 210C is electrically connected to the first segment 212A at a positive input terminal of the motor controller 206. A fourth capacitive arc fault sensor 210D is electrically connected to the second segment 212B at a negative input terminal of the motor controller 206. The pair of capacitive arc fault sensors 210A and 210C monitors arcs on the positive rail 212A between the DC power source 208 and the motor controller 206. The pair of capacitive arc fault sensors 210B and 210D monitors arcs on the negative rail 212B between the DC power source 208 and the motor controller 206. The arc fault sensors 210A, 210B, 210C, 210D monitor the HVDC section of the power distribution system 202. In addition, a fifth capacitive arc fault sensor 210E is electrically connected to the third section 212C at the output terminals of the motor controller 206. A sixth capacitive arc fault sensor 210F is electrically connected to the third section 212C at the input terminals of the motor 204. The pair of capacitive arc fault sensors 210E and 210F monitors arcs on the third section 212C between the motor controller 206 and the motor 204. The third section 212C is the HVAC section of the power distribution system 202. The arc fault detection system 200 performs arc fault detection on the HVAC section in the same or similar manner as it performs arc fault detection on the HVDC section of the power distribution system 202.

[0025] The arc fault detection system 200 includes an arc fault detector 214 electrically connected to a plurality of capacitive arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F. Each of the plurality of capacitive arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F is configured to output an arc fault signal based at least on detecting a high frequency current generated by an arc fault. In one example, the frequency range in which the capacitive arc fault sensor detects an arc fault is at least 10 MHz and extends to the GHz range. Specifically, each of the plurality of capacitive arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F generates a voltage in response to detecting a high frequency component of a current generated from capacitive coupling with an arc. The first capacitive arc fault sensor 210A outputs a voltage V a1p The second capacitive arc fault sensor 210B outputs a voltage V a1n The third capacitive arc fault sensor 210C outputs a voltage V a2p The fourth capacitive arc fault sensor 210D outputs a voltage V a2n The fifth capacitive arc fault sensor 210E outputs a voltage V ac_1 The sixth capacitive arc fault sensor 210F outputs a voltage V ac_2 Arc fault signal.

[0026] In the illustrated embodiment, the arc fault 216 is interrupted on the positive section 212A and generates an energy wave that propagates bidirectionally along the positive section 212A. The energy wave generated by the arc fault 216 has a characteristic defined by high frequency voltage distortion. When the energy wave reaches the first arc fault sensor 210A and the third arc fault sensor 210C, the first arc fault sensor 210A and the third arc fault sensor 210C report arc fault signals (e.g., V a1p and V a2p ). Note that if an arc fault occurs in parallel across the positive segment 212A and the negative segment 212B, the capacitive arc fault sensors electrically connected to those segments will detect the arc fault and report an arc fault signal in response.

[0027] The pattern of time delays, voltage distortions, along with the amplitude or strength of the arc signal can be used to determine the location of the arc fault. The amplitude of the arc fault signal can indicate the proximity of the arc fault to the corresponding capacitive arc fault sensor. For example, an arc fault signal of a larger amplitude indicates a closer proximity between the arc fault and the capacitive arc fault sensor relative to an arc fault signal of a smaller amplitude. However, as the arc fault signal travels along the signal path (e.g., a conductor), the amplitude of the arc fault signal decays. In addition, since signals of different frequencies propagate at different speeds, the phase of the arc fault signal is offset. This amplitude decay and phase shift can be a function of the distance between the arc fault and the capacitive arc fault sensor and the distance between the capacitive arc fault sensor and the arc fault detector 214.

[0028] The arc fault detector 214 is configured to receive one or more arc fault signals from one or more capacitive arc fault sensors of the plurality of capacitive arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F. In some embodiments, in order to accurately determine the location of the arc fault, the arc fault detector 214 can be configured to apply one or more correction factors to one or more phases (or arrival times) of the one or more arc fault signals to account for propagation delays caused by differences in lengths of the signal paths of the plurality of arc fault signals. In some examples, the correction factor(s) can be a function of the length of the signal path between each of the plurality of capacitive arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F and the arc fault detector 214. Such correction factor(s) can normalize the phase differences (and / or arrival time differences) of the different arc fault signals to account for the different signal path lengths, so that the magnitude of the phase correction of the different arc fault signals can be evaluated to accurately determine the location of the arc fault.

[0029] In other embodiments, each of the plurality of arc fault sensors 210A, 210B, 210C, 210D, 210E, 210F may be arranged to have the same signal path length between each arc fault sensor and the arc fault detector 214, thereby alleviating the need for such correction factor(s) to compensate for the different signal path lengths.

[0030] Arc fault detector 214 is configured to determine the location of an arc fault in power distribution system 202 based at least on one or more arc fault signals received from one or more capacitive arc fault sensors. Arc fault detector 214 may include any suitable combination of hardware, firmware, and / or software to execute any suitable algorithm to determine the location of an arc fault based on one or more arc fault signals.

[0031] In one example where arc fault detector 214 receives an arc fault signal from a single capacitive arc fault sensor, arc fault detector 214 is configured to determine that the location of the arc fault is on a segment corresponding to the capacitive arc fault sensor that sent the single arc fault signal to arc fault detector 214. In this case, other capacitive arc fault sensors may not report any high frequency voltage distortion.

[0032] In another example where arc fault detector 214 receives multiple arc fault signals from multiple arc fault sensors, as in the example shown, arc fault detector 214 is configured to determine the location of the arc fault based at least on the difference in magnitude of the multiple arc fault signals (also taking into account any correction factors applied to compensate for signal path lengths between the different sensors and arc fault detector 214). For example, if arc fault detector receives arc fault signals from both first arc fault sensor 210A and third arc fault sensor 210C, arc fault detector 214 determines that the arc fault is located on first zone 212A.

[0033] In addition, in some embodiments, the arc fault detector 214 can compare the magnitudes of the arc fault signals to make a more granular determination of where the arc fault is located on the first segment 212A. For example, if the magnitude of the arc fault signal received from the first arc fault sensor 210A is greater than the magnitude of the arc fault signal received from the third arc fault sensor 210C, the arc fault detector 214 determines that the arc fault 216 is located on the first segment 212A closer to the DC power source 208 than the motor controller 206. In some embodiments, the arc fault detector 214 can be configured to apply a distance function to the magnitudes to estimate the location of the arc fault 216 on the first segment 212A. The arc fault detector 214 can determine the location of the arc fault using any suitable algorithm at any suitable granularity. Note that the magnitudes used by the arc fault detector 214 can have correction factors (multiple) applied to them to account for different signal path lengths between different capacitive arc fault sensors and the arc fault detector 214.

[0034] Figure 3 Another exemplary embodiment of an arc fault detection system 300 for an electric power distribution system 302 including a plurality of electric motors 304A, 304B is schematically illustrated. For example, the electric power distribution system 302 may represent the electric power distribution system 102, and the arc fault detection system 300 may represent Figure 1 The arc fault detection system 114 is shown. The power distribution system 302 has a Figure 2The illustrated power distribution system 202 has more sections. Accordingly, the arc fault detection system 300 includes more capacitive arc fault sensors than the arc fault detection system 200 in order to monitor arc faults on these additional sections.

[0035] The power distribution system 302 includes a DC power supply 306, a PDP 308, a first motor controller 310A, a second motor controller 310B, a first motor 304A, and a second motor 304B. The DC power supply 306 is configured to output DC power to the PDP 308. The PDP 308 is configured to distribute the power received from the DC power supply 306 to two parallel loads in the form of a first motor controller 310A and a second motor controller 310B electrically connected to a corresponding pair of motors 304A, 304B. The first motor controller 310A and the second motor controller 310B are configured to modulate the power received from the PDP 308 to control the speed and / or torque of the motors 304A, 304B. The power distribution system 302 includes a plurality of sections 312A, 312B, 312C, 312D, 312E, 312F that electrically connect different electronic components of the power distribution system 302. The first section 312A electrically connects the positive output terminal of the DC power supply 306 to the positive terminal of the PDP 308. The second section 312B electrically connects the negative output terminal of the DC power supply 306 to the negative terminal of the PDP 308. The third section 312C electrically connects the positive terminal of the PDP 308 to the positive terminal of the first motor controller 310A. The fourth section 312D electrically connects the negative terminal of the PDP 308 to the negative terminal of the first motor controller 310A. The fifth section 312E electrically connects the positive terminal of the PDP 308 to the positive terminal of the second motor controller 310B. The sixth section 312F electrically connects the negative terminal of the PDP 308 to the negative terminal of the second motor controller 310B.

[0036] The arc fault detection system 300 includes a plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H electrically connected to the plurality of segments 312A, 312B, 312C, 312D, 312E, 312F. A first capacitive arc fault sensor 314A is electrically connected to the first segment 312A at a positive terminal of the DC power supply 306. A second capacitive arc fault sensor 314B is electrically connected to the second segment 312B at a negative terminal of the DC power supply 306. A third capacitive arc fault sensor 314C is electrically connected to the first segment 312A at a positive terminal of the PDP 308. A fourth capacitive arc fault sensor 314D is electrically connected to the second segment 312B at a negative terminal of the PDP 308. A fifth capacitive arc fault sensor 314E is electrically connected to the third section 312C at the positive terminal of the first motor controller 310A. A sixth capacitive arc fault sensor 314F is electrically connected to the fourth section 312D at the negative terminal of the first motor controller 310A. A seventh capacitive arc fault sensor 314G is electrically connected to the fifth section 312E at the positive terminal of the second motor controller 310B. An eighth capacitive arc fault sensor 314H is electrically connected to the sixth section 312F at the negative terminal of the second motor controller 310B.

[0037] Although not shown for clarity, in some embodiments, the arc fault detection system 300 can include additional capacitive arc fault sensors positioned on the section between the first motor controller 310A and the first motor 304A and the section between the second motor controller 310B and the second motor 304B. Such additional capacitive arc fault sensors can operate in the same manner as the other capacitive arc fault sensors of the arc fault detection system 300 described herein.

[0038] Each of the plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H is configured to output an arc fault signal based at least on the detection of a high frequency current generated by capacitive coupling with the arc. Specifically, each of the plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H generates a voltage in response to detecting a high frequency component of the current generated by capacitive coupling with the arc. The first capacitive arc fault sensor 314A outputs a voltage V a1p The second capacitive arc fault sensor 314B outputs a voltage V a1n The third capacitive arc fault sensor 314C outputs a voltage V a2pThe fourth capacitive arc fault sensor 314D outputs a voltage V a2n The fifth capacitive arc fault sensor 314E outputs a voltage V a3p The sixth capacitive arc fault sensor 314F outputs a voltage V a3n The seventh capacitive arc fault sensor 314G outputs a voltage V a4p The eighth capacitive arc fault sensor 314H outputs a voltage V a4n Arc fault signal.

[0039] In the illustrated embodiment, the arc fault 316 is interrupted on the positive section 312A between the DC power source 306 and the PDP 308 and generates an energy wave that propagates bidirectionally along the positive section 312A. The energy wave generated by the arc fault 316 has a characteristic defined by high frequency voltage distortion. When the energy wave reaches different capacitive arc fault sensors, the different capacitive arc fault sensors report arc fault signals to the arc fault detector 318.

[0040] The arc fault detector 318 is electrically connected to the plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H. The arc fault detector 318 is configured to receive one or more arc fault signals from one or more capacitive arc fault sensors of the plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H and determine a location of an arc fault in the power distribution system 302 based at least on the one or more arc fault signals.

[0041] In some embodiments, the arc fault detector 318 is configured to apply one or more correction factors to one or more phases (or one or more arrival times) of one or more arc fault signals in the plurality of arc fault signals to account for propagation delays due to differences in lengths of signal paths of the plurality of arc fault signals. In some examples, the correction factor(s) may be a function of the length of the signal path between each of the plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H and the arc fault detector 318.

[0042] The arc fault detector 318 is configured to determine the location of the arc fault based at least on the difference in amplitude, arrival time, and / or phase of the arc fault signals received from the plurality of capacitive arc fault sensors 314A, 314B, 314C, 314D, 314E, 314F, 314G, 314H. Figure 2 As the arc fault detection system 200 is shown monitoring an increased number of zones, the arc fault detector 318 may employ more complex detection algorithms or other logic to determine the location of an arc fault on a particular zone among all of the zones being monitored.

[0043] In some embodiments, arc fault detector 318 includes a lookup table (LUT) 320 configured to map the magnitude, arrival time, and / or phase of one or more received arc fault signals to one or more potential locations in power distribution system 302. In such embodiments, the location of the arc fault is determined based on the location output from LUT 320.

[0044] Figure 4 An exemplary table 400 is shown, which includes the responses of different capacitive arc fault sensors to the Figure 3 400. For example, the arc fault detector 318 may use a lookup table similar to table 400 to determine the location of the arc fault in the power distribution system 302. Table 400 includes columns associated with different arc fault signals from different capacitive arc fault sensors. Table 400 includes rows associated with different sections of the power distribution system 302. Table 400 includes the amplitude of the arc fault signal of the capacitive arc fault sensor electrically connected to the positive section within the power distribution system 302 for simplicity only. Note that the amplitude over the specific frequency range of interest shown in table 400 is generalized as high (H) or medium / low (M / L). The ratio of M / L will be defined by the details of the specific architecture (such as the length of the section, the gauge of the wire, the terminal, etc.). In practice, such amplitudes may have more precise values, and the table will also include the amplitude of the arc fault signal of the capacitive arc fault sensor electrically connected to the negative section within the power distribution system 302.

[0045] According to table 400, if an arc fault occurs in the first segment 312A between the DC power source 306 and the PDP 308, the first capacitive arc fault sensor 314A and the third capacitive arc fault sensor 314C report arc fault signals with high amplitudes because these sensors are closest to the location of the arc fault. The fifth capacitive arc fault sensor 314E and the seventh capacitive arc fault sensor 314G report arc fault signals with medium / low amplitudes because these sensors are located on segments further away from the location of the arc fault. Note that these sensors are still able to detect arc faults because the electric waves generated by the arc fault travel through the PDP to the third segment 312C and the fifth segment 312E corresponding to the fifth capacitive arc fault sensor 314E and the seventh capacitive arc fault sensor 314G.

[0046] If an arc fault occurs in the third section 312C between the PDP 308 and the first motor controller 310A, the third capacitive arc fault sensor 314C and the fifth capacitive arc fault sensor 314E report arc fault signals with high amplitudes because these sensors are closest to the location of the arc fault. The first capacitive arc fault sensor 314A and the second capacitive arc fault sensor 314G report arc fault signals with medium / low amplitudes because these sensors are located on sections further away from the location of the arc fault.

[0047] If an arc fault occurs in the fifth section 312E between the PDP 308 and the second motor controller 310B, the third capacitive arc fault sensor 314C and the seventh capacitive arc fault sensor 314G report arc fault signals with high amplitudes because these sensors are closest to the location of the arc fault. The first capacitive arc fault sensor 314A and the fifth capacitive arc fault sensor 314E report arc fault signals with medium / low amplitudes because these sensors are located on sections further away from the location of the arc fault.

[0048] Table 400 is provided as a non-limiting example of how the arc fault detector 318 may use the lookup table to determine the location of an arc fault in the power distribution system 302. Note that in the illustrated embodiment, the arc fault signal of the third capacitive arc fault sensor should always have a high magnitude based on an arc fault occurring on a positive segment within the power distribution system 302. If the arc fault signal of the third capacitive arc fault sensor does not have a high magnitude, then the third capacitive arc fault sensor may be degraded or the power distribution system 302 may have another problem.

[0049] In some embodiments, the arc fault detector 318 is configured to perform analysis on different pairs of arc fault signals received from different capacitive arc fault sensors to determine the magnitude, arrival time, and / or phase associated with each of the plurality of sections 312A, 312B, 312C, 312D, 312E, 312F of the power distribution system 302. For example, the pairwise analysis may include comparing the magnitude (e.g., |V a1p |-V a2p |) and the amplitude of the third segment 312C (eg, |V a2p |-V a3p |) and the magnitude of the fifth segment 312E (eg, |V a2p |-V a4p |) are compared to determine the maximum amplitude of different sections. Further, arc fault detector 318 is configured to determine, based on a pairwise analysis of different arc fault signals, that the location of the arc fault corresponds to the section with the highest amplitude and / or lowest phase (and / or shortest arrival time) among the multiple sections.

[0050] In some embodiments, the arc fault detector 318 is configured to perform a check for false positive readings in order to improve the robustness of the arc fault detection system 300. More specifically, in some embodiments, after the arc fault detector 318 performs a pairwise analysis of different arc fault signals to determine the segment with the highest amplitude and / or the lowest phase, the arc fault detector 318 is configured to compare the highest amplitude with an amplitude error threshold and the lowest phase with a phase error threshold, and based on at least one of the amplitude being less than the amplitude error threshold or the lowest phase being greater than the phase error threshold, the arc fault detector 318 determines that the arc fault is a false positive. In some such cases, the false positive may be attributable to system noise.

[0051] In some embodiments, the arc fault detector 318 can be configured to determine the location of the arc fault based on at least a pair of arc fault signals having an amplitude within an amplitude difference threshold and a phase within a phase difference threshold, based on at least a time difference of arrival of the arc fault signals. The amplitude difference threshold and the phase difference threshold can be set to indicate that the amplitude and phase are the same or substantially similar (within a specific tolerance level of the threshold). In other words, when the amplitude and phase of two different arc fault signals are the same or similar (also the highest amplitude and the lowest phase), this indicates that the capacitive arc fault sensor that issued the arc fault signals is located closest to the arc fault (e.g., on the opposite side of the section where the arc fault occurred). In this case, the arc fault detector 318 can determine the location of the arc fault based on at least the time difference of arrival of the two arc fault signals. For example, the location of the arc fault can be estimated based on calculating the distance from the capacitive arc fault sensors as a function of the arrival time. In an example where the arrival time is substantially the same, the arc fault can be located equidistant from the two capacitive arc fault sensors.

[0052] In some embodiments, the arc fault detection system 300 is configured to perform different mitigation operations based at least on the detection of an arc fault. For example, the arc fault detection system 300 is configured to disable specific electronic components affected by the arc fault. For example, if an arc fault is detected in the third section 312C between the PDP 308 and the first motor controller 310A, the arc fault detection system 300 can disable the operation of the first motor 304A until the problem can be resolved. The arc fault detection system 300 can be configured to perform any suitable mitigation operation in response to detecting an arc fault and determining the location of the arc fault.

[0053] In some embodiments, arc fault detection system 300 is configured to send a notification of an arc fault including a location of the arc fault (eg, a zone and / or a location within a zone) to power distribution system 302 , and power distribution system 302 may perform different mitigation operations.

[0054] Figure 5 An exemplary embodiment of a capacitive arc fault sensor 500 is schematically shown. For example, the capacitive arc fault sensor 500 may represent Figure 1 The arc fault detection system 114 shown in Figure 2 The arc fault detection system 200 shown in Figure 3The capacitive arc fault sensor of the arc fault detection system 300 shown in FIG. 5 is electrically connected to the segment in the form of a cable 501. The cable 501 includes a plurality of layers, including an outer jacket 502, an outer insulating layer 504 disposed within the outer jacket 502, a metal shielding layer 506 disposed within the outer insulating layer 504, an inner insulating layer 508 disposed within the metal shielding layer 506, and a conductor 510 disposed within the inner insulating layer 508. The capacitive arc fault sensor 500 is connected to the inner insulating layer 508 to facilitate capacitive coupling between the arc fault sensor 500 and the conductor 510 when an arc fault occurs in the cable 501.

[0055] In some embodiments, the inner insulating layer 508 is wrapped in a conductive wrap (e.g., conductive foil) 512 at the connection point of the capacitive arc fault sensor 500. The conductive wrap 512 is not integral with the cable 501, but is added during the installation of the capacitive arc fault sensor 500 on the cable 501. When an arc fault occurs, the conductive wrap 512 enhances the coupling coefficient of the capacitive arc fault sensor 500 to increase the capacitive coupling with the capacitive arc fault sensor 500.

[0056] In some embodiments, a fuse 514 is electrically connected between the capacitive arc fault sensor 500 and the arc fault detector. The fuse 514 protects the arc fault detector from a short circuit condition. For example, if the inner insulation layer 508 of the cable 501 does not allow contact between the conductor 510 and the capacitive arc fault sensor 500, a short circuit condition may occur.

[0057] In some embodiments, a high pass filter (HPF) 516 is electrically connected between the capacitive arc fault sensor 500 and the arc fault detector. The HPF 516 filters out low frequency system noise to increase the signal-to-noise ratio (SNR) of high frequency components of the arc fault signal output from the capacitive arc fault sensor 500 .

[0058] In some embodiments, the signal amplifier 518 is electrically connected between the capacitive arc fault sensor 500 and the arc fault detector. The signal amplifier 518 increases the signal level of the arc fault signal output from the capacitive arc fault sensor 500 to increase the overall SNR of the arc fault signal provided to the arc fault detector.

[0059] Figure 6 An exemplary embodiment of an arc fault detection method 600 is shown. For example, the method 600 may be performed by Figure 1 The arc fault detector 118 shown, Figure 2 The arc fault detector 214 or Figure 3Arc fault detector 318 is shown implemented.

[0060] At 602, method 600 includes receiving one or more arc fault signals from one or more capacitive arc fault sensors of a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of a power distribution system. The arc fault signals are output from the capacitive arc fault sensors based at least on the capacitive arc fault sensors detecting a high frequency current generated from capacitive coupling with an arc.

[0061] In some embodiments, at 604 , method 600 can include applying one or more correction factors to one or more arrival times and / or phases of one or more arc fault signals of the plurality of arc fault signals to account for propagation delays due to differences in lengths of signal paths of the plurality of arc fault signals.

[0062] At 606 , method 600 includes determining a location of an arc fault in the power distribution system based at least on the one or more arc fault signals.

[0063] In some embodiments, at 608, method 600 can include determining a location of the arc fault based at least on a difference in amplitudes of the plurality of arc fault signals. For example, a section of the power distribution system connected to a capacitive arc fault sensor that outputs an arc fault signal having a maximum amplitude can be determined as the location of the arc fault. In some examples, the amplitudes compared for location determination can be corrected based on a correction factor to account for differences in signal path lengths.

[0064] In some embodiments, at 610, method 600 can include determining a location of the arc fault based at least on a time of arrival difference and / or a phase difference of the plurality of arc fault signals. For example, a section of the power distribution system connected to a capacitive arc fault sensor that outputs an arc fault signal having the shortest time of arrival and / or the lowest phase can be determined as the location of the arc fault. In some examples, the phases compared for location determination can be corrected based on a correction factor to account for differences in signal path lengths.

[0065] In some embodiments, at 612, method 600 can include providing one or more amplitudes, one or more arrival times, and one or more phases of the one or more arc fault signals as inputs to a lookup table. The lookup table is configured to map one or more amplitudes, arrival times, and / or one or more phases of the one or more arc fault signals to one or more locations in the power distribution system, and the location of the arc fault is determined based on the location output from the lookup table.

[0066] In some embodiments, at 614 , method 600 can include performing a pairwise analysis on different pairs of arc fault signals received from the plurality of capacitive arc fault sensors to determine the magnitude, arrival time, and / or phase associated with each of the plurality of sections of the power distribution system.

[0067] In some implementations, at 616 , method 600 can include determining that the location of the arc fault is on a segment of the plurality of segments having the highest magnitude and shortest arrival time and / or lowest phase.

[0068] In some embodiments, at 618, method 600 may include: comparing the highest amplitude with an amplitude error threshold, comparing the lowest phase with a phase error threshold; and determining that the arc fault is a false positive based on at least one of the amplitude being less than the amplitude error threshold or the lowest phase being greater than the phase error threshold.

[0069] In some embodiments, at 620, method 600 may include determining the location of the arc fault based at least on a pair of arc fault signals having an amplitude within an amplitude difference threshold and a phase within a phase difference threshold, based at least on a time difference of arrival of the arc fault signals. The amplitude difference threshold and the phase difference threshold may be set to indicate that the amplitude and phase are the same or substantially similar (within a certain tolerance level of the threshold). In other words, when the amplitude and phase of two different arc fault signals are the same or similar (also the highest amplitude and the lowest phase), this indicates that the capacitive arc fault sensor that issued the arc fault signals is located closest to the arc fault (e.g., on the opposite side of the segment where the arc fault occurred). In this case, the location of the arc fault may be determined based at least on the time difference of arrival of the two arc fault signals. For example, the location of the arc fault may be estimated based on calculating the distance from the capacitive arc fault sensors as a function of the arrival time. In an example where the arrival times are substantially the same, the arc fault may be located equidistant from the two capacitive arc fault sensors.

[0070] The arc fault detection method described above may be performed to accurately detect the location of an arc fault in a power distribution system.

[0071] The methods and processes described herein may be bound to a computing system of one or more computing devices. Figure 7 The schematic diagram shows a simplified representation of a computing system 700 that is configured to provide any of the computing functions described herein. For example, the computing system 700 may represent Figure 1 The arc fault detector 118 shown in Figure 2 The arc fault detector 214 shown in FIG. Figure 3 The arc fault detector 318 shown in FIG.

[0072] The computing system 700 includes a logic subsystem 702 and a storage subsystem 704. The computing system 700 may optionally include a display subsystem 706, an input subsystem 708, a communication subsystem 710, and / or Figure 7 Other subsystems not shown.

[0073] The logic subsystem 702 includes one or more physical devices configured to execute instructions. For example, the logic subsystem may be configured to execute instructions as part of one or more applications, services, or other logical structures. The logic subsystem may include one or more hardware processors configured to execute software instructions. Additionally or alternatively, the logic subsystem may include one or more hardware or firmware devices configured to execute hardware or firmware instructions. The processor of the logic subsystem may be single-core or multi-core, and the instructions executed thereon may be configured for sequential, parallel, and / or distributed processing. The individual components of the logic subsystem may optionally be distributed in two or more separate devices, which may be remotely located and / or configured for collaborative processing. Aspects of the logic subsystem may be virtualized and executed by a remotely accessible networked computing device configured in a cloud computing configuration.

[0074] The storage subsystem 704 includes one or more physical devices configured to temporarily and / or permanently hold computer information such as instructions and data that can be executed by the logic subsystem. When the storage subsystem includes two or more devices, the devices can be collocated and / or remotely located. The storage subsystem 704 may include volatile, non-volatile, dynamic, static, read / write, read-only, random access, sequential access, location addressable, file addressable, and / or content addressable devices. The storage subsystem 704 may include removable and / or built-in devices. As the logic subsystem executes instructions, the state of the storage subsystem 704 may be transformed—for example, to hold different data.

[0075] Aspects of logic subsystem 702 and storage subsystem 704 may be integrated together into one or more hardware logic components. Such hardware logic components may include, for example, program and application specific integrated circuits (PASIC / ASIC), program and application specific standard products (PSSP / ASSP), systems on chips (SOC), and complex programmable logic devices (CPLD).

[0076] The logic subsystem and the storage subsystem can collaborate to instantiate one or more logic machines. As used herein, the term "machine" is used to collectively refer to a combination of hardware, firmware, software, instructions, and / or any other components that collaborate to provide computer functionality. In other words, a "machine" is never an abstract concept and always has a tangible form. A machine may be instantiated by a single computing device, or a machine may include two or more subcomponents instantiated by two or more different computing devices. In some implementations, a machine includes a local component (e.g., a software application executed by a computer processor) that collaborates with a remote component (e.g., a cloud computing service provided by a network of server computers). The software and / or other instructions that give a particular machine its functionality may optionally be saved as one or more unexecuted modules on one or more suitable storage devices.

[0077] When a display subsystem 706 is included, the display subsystem 706 can be used to present a visual representation of the data maintained by the storage subsystem 704. The visual representation can take the form of a graphical user interface (GUI). The display subsystem 706 can include one or more display devices utilizing nearly any type of technology. In some implementations, the display subsystem can include one or more virtual, augmented, or mixed reality displays.

[0078] When input subsystem 708 is included, input subsystem 708 may include or interface with one or more input devices. An input device may include a sensor device or a user input device. Examples of user input devices include a keyboard, a mouse, a touch screen, or a game controller.

[0079] When included, the communication subsystem 710 can be configured to communicatively couple the computing system 700 with one or more other computing devices. The communication subsystem 710 can include wired and / or wireless communication devices compatible with one or more different communication protocols. The communication subsystem can be configured to communicate via personal, local, and / or wide area networks.

[0080] In an example, an arc fault detection system includes a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of an electric power distribution system, wherein each capacitive arc fault sensor is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc, and an arc fault detector electrically connected to the plurality of capacitive arc fault sensors, wherein the arc fault detector is configured to receive one or more arc fault signals from one or more of the plurality of capacitive arc fault sensors, and determine a location of an arc fault in the electric power distribution system based at least on the one or more arc fault signals. In this example and / or other examples, the arc fault detector may receive a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and the arc fault detector may be configured to determine the location of the arc fault based at least on a difference in amplitude of the plurality of arc fault signals. In this example and / or other examples, the arc fault detector may receive a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and the arc fault detector may be configured to determine the location of the arc fault based at least on a difference in arrival time and / or a difference in phase of the plurality of arc fault signals. In this example and / or other examples, the arc fault detector can be configured to apply one or more correction factors to one or more arrival times and / or one or more phases of one or more arc fault signals in the plurality of arc fault signals to account for propagation delays caused by length differences in signal paths of the plurality of arc fault signals. In this example and / or other examples, the arc fault detector can include a lookup table configured to map one or more amplitudes, arrival times, and / or one or more phases of the one or more arc fault signals to one or more locations in the power distribution system, and wherein the location of the arc fault is determined based on the location output from the lookup table. In this example and / or other examples, the arc fault detector can be configured to analyze different pairs of arc fault signals received from different capacitive arc fault sensors in the plurality of capacitive arc fault sensors to determine the amplitude, arrival time, and / or phase associated with each of the plurality of different sections of the power distribution system, and the location of the arc fault is determined to correspond to the section of the plurality of different sections having the highest amplitude and the lowest phase. In this example and / or other examples, the arc fault detector can be configured to compare the highest amplitude of the corresponding segment with an amplitude error threshold, and compare the lowest phase of the corresponding segment with a phase error threshold, and determine that the arc fault is a false positive based on at least one of the highest amplitude being less than the amplitude error threshold or the lowest phase being greater than the phase error threshold.In this example and / or other examples, the arc fault detector can be configured to determine the location of the arc fault based on at least a pair of arc fault signals having an amplitude within an amplitude difference threshold and a phase within a phase difference threshold, based on at least a time difference of arrival of the arc fault signals. In this example and / or other examples, the plurality of capacitive arc fault sensors can include a first capacitive arc fault sensor and a second capacitive arc fault sensor, the first capacitive arc fault sensor can be electrically connected to a first segment, the first segment is electrically connected to a positive output node of a direct current (DC) power supply of the power distribution system, and the second capacitive arc fault sensor can be electrically connected to a second segment, the second segment is electrically connected to a negative output node of the DC power supply. In this example and / or other examples, the power distribution system can be configured to distribute power to a plurality of motors, the plurality of motors can be controlled by a corresponding plurality of motor controllers electrically connected to the DC power supply via a plurality of segments of the power distribution system, and the plurality of capacitive arc fault sensors can be electrically connected to the plurality of segments located between the corresponding plurality of motor controllers and the DC power supply. In this example and / or other examples, a power distribution system may include a power distribution panel (PDP) electrically connected to a DC power source and intermediate a corresponding plurality of motor controllers and the DC power source, and a plurality of capacitive arc fault sensors including a first subset of capacitive arc fault sensors electrically connected to a section intermediate the DC power source and the PDP and a second subset of capacitive arc fault sensors electrically connected to a section intermediate the PDP and the corresponding plurality of motor controllers.

[0081] In another example, an arc fault detection method for an electric power distribution system includes: receiving one or more arc fault signals from one or more capacitive arc fault sensors of a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of the electric power distribution system, wherein each of the plurality of capacitive arc fault sensors is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc, and determining a location of an arc fault in the electric power distribution system based at least on the one or more arc fault signals. In this example and / or other examples, the method may further include receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and determining a location of the arc fault based at least on a difference in amplitude of the plurality of arc fault signals. In this example and / or other examples, the method may further include receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and determining a location of the arc fault based at least on a difference in arrival time and / or a difference in phase of the plurality of arc fault signals. In this difference and / or other differences, the method may further include applying one or more correction factors to one or more arrival times and / or one or more phases of one or more arc fault signals in the plurality of arc fault signals to account for propagation delays caused by differences in lengths of signal paths of the plurality of arc fault signals. In this difference and / or other differences, determining the location of the arc fault may include providing one or more amplitudes, one or more arrival times, and / or one or more phases of the one or more arc fault signals as inputs to a lookup table, the lookup table may be configured to map the one or more amplitudes, the one or more arrival times, and / or the one or more phases of the one or more arc fault signals to one or more locations in the power distribution system, and the location of the arc fault may be determined based on the location output from the lookup table. In this difference and / or other differences, the method may further include receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and performing analysis on different pairs of arc fault signals received from the plurality of capacitive arc fault sensors to determine an amplitude and phase associated with each of the plurality of different sections of the power distribution system, and wherein the location of the arc fault is determined to be at a section of the plurality of different sections having a highest amplitude and a lowest phase. In this difference and / or other differences, the method may further include comparing the highest amplitude of the corresponding section with an amplitude error threshold, comparing the lowest phase of the corresponding section with a phase error threshold, and determining that the arc fault is a false positive based on at least one of the highest amplitude being less than the amplitude error threshold or the lowest phase being greater than the phase error threshold.

[0082] In yet another example, the storage subsystem retains instructions executable by the logic subsystem to: receive one or more arc fault signals from one or more capacitive arc fault sensors of a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of a power distribution system, wherein each of the plurality of capacitive arc fault sensors is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc, and determine a location of an arc fault in the power distribution system based at least on the one or more arc fault signals. In this example and / or other examples, the instructions may be executable by the logic subsystem to receive a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and determine a location of the arc fault based at least on a difference in amplitude of the plurality of arc fault signals, a difference in arrival time of the plurality of arc fault signals, and / or a difference in phase of the plurality of arc fault signals.

[0083] The present disclosure includes all novel and non-obvious combinations and sub-combinations of the various features and techniques disclosed herein. The various features and techniques disclosed herein are not necessarily required for all examples of the present disclosure. In addition, the various features and techniques disclosed herein may define patentable subject matter other than the disclosed examples, and may find utility in other implementations not explicitly disclosed herein.

Claims

1. An arc fault detection system, comprising: a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of the power distribution system, wherein each capacitive arc fault sensor is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc; and an arc fault detector electrically connected to the plurality of capacitive arc fault sensors, wherein the arc fault detector is configured to: receiving one or more arc fault signals from one or more capacitive arc fault sensors of the plurality of capacitive arc fault sensors; and A location of an arc fault in the power distribution system is determined based at least on the one or more arc fault signals.

2. The arc fault detection system according to claim 1, wherein: The arc fault detector receives a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and wherein the arc fault detector is configured to determine the location of the arc fault based at least on a difference in amplitudes of the plurality of arc fault signals.

3. The arc fault detection system according to claim 1, wherein: The arc fault detector receives a plurality of arc fault signals from the plurality of capacitive arc fault sensors, and wherein the arc fault detector is configured to determine the location of the arc fault based at least on arrival time differences and / or phase differences of the plurality of arc fault signals.

4. The arc fault detection system according to claim 3, wherein: The arc fault detector is configured to apply one or more correction factors to one or more arrival times and / or one or more phases of one or more arc fault signals of the plurality of arc fault signals to account for propagation delays due to differences in lengths of signal paths of the plurality of arc fault signals.

5. The arc fault detection system according to claim 1, wherein: The arc fault detector comprises a lookup table configured to map one or more amplitudes, one or more arrival times, and / or one or more phases of the one or more arc fault signals to one or more locations in the power distribution system, and wherein the location of the arc fault is determined based on a location output from the lookup table.

6. The arc fault detection system according to claim 1, wherein: The arc fault detector is configured to analyze different pairs of arc fault signals received from different capacitive arc fault sensors among the plurality of capacitive arc fault sensors to determine an amplitude and a phase associated with each of the plurality of different sections of the power distribution system, and wherein the location of the arc fault is determined to correspond to the section of the plurality of different sections having the highest amplitude and the lowest phase.

7. The arc fault detection system according to claim 6, wherein: The arc fault detector is configured to compare the highest amplitude of the corresponding segment with an amplitude error threshold, and to compare the lowest phase of the segment with a phase error threshold, and to determine that the arc fault is a false positive based on at least one of the highest amplitude being less than the amplitude error threshold or the lowest phase being greater than the phase error threshold.

8. The arc fault detection system according to claim 6, wherein: The arc fault detector is configured to determine the location of the arc fault based on at least a pair of arc fault signals having an amplitude within an amplitude difference threshold and a phase within a phase difference threshold based on at least a difference in arrival time of the arc fault signals.

9. The arc fault detection system according to claim 1, wherein: The plurality of capacitive arc fault sensors include a first capacitive arc fault sensor and a second capacitive arc fault sensor, wherein the first capacitive arc fault sensor is electrically connected to a first segment, the first segment is electrically connected to a positive output node of a direct current (DC) power supply of the power distribution system, and wherein the second capacitive arc fault sensor is electrically connected to a second segment, the second segment is electrically connected to a negative output node of the DC power supply.

10. The arc fault detection system according to claim 9, wherein: The power distribution system is configured to distribute power to a plurality of motors, wherein the plurality of motors are controlled by a corresponding plurality of motor controllers, the plurality of motor controllers are electrically connected to the DC power supply via a plurality of sections of the power distribution system, and wherein the plurality of capacitive arc fault sensors are electrically connected to a plurality of sections intermediate the corresponding plurality of motor controllers and the DC power supply.

11. The arc fault detection system according to claim 10, wherein: The power distribution system includes a power distribution panel (PDP) electrically connected to the DC power supply and intermediate the corresponding plurality of motor controllers and the DC power supply, and wherein the plurality of capacitive arc sensors include a first subset of capacitive arc fault sensors electrically connected to a section intermediate the DC power supply and the PDP, and a second subset of capacitive arc fault sensors electrically connected to a section intermediate the PDP and the corresponding plurality of motor controllers.

12. A method for detecting arc faults in a power distribution system, the method comprising: receiving one or more arc fault signals from one or more capacitive arc fault sensors of a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of the power distribution system, wherein each capacitive arc fault sensor of the plurality of capacitive arc fault sensors is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc; and Based at least on the one or more arc fault signals, a location of an arc fault in the power distribution system is determined.

13. The method according to claim 12, further comprising: receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors; as well as The location of the arc fault is determined based at least on a difference in magnitudes of the plurality of arc fault signals.

14. The method according to claim 12, further comprising: receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors; as well as The location of the arc fault is determined based at least on arrival time differences and / or phase differences of the plurality of arc fault signals.

15. The method according to claim 14, further comprising: One or more correction factors are applied to one or more arrival times and / or one or more phases of one or more arc fault signals of the plurality of arc fault signals to account for propagation delays due to differences in lengths of signal paths of the plurality of arc fault signals.

16. The method according to claim 12, wherein: Determining the location of the arc fault includes providing one or more amplitudes, one or more arrival times, and / or one or more phases of the one or more arc fault signals as inputs to a lookup table, wherein the lookup table is configured to map the one or more amplitudes, the one or more arrival times, and / or the one or more phases of the one or more arc fault signals to one or more locations in the power distribution system, and wherein the location of the arc fault is determined based on a location output from the lookup table.

17. The method according to claim 12, further comprising: receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors; as well as An analysis is performed on different pairs of arc fault signals received from the plurality of capacitive arc fault sensors to determine an amplitude and a phase associated with each of the plurality of different sections of the power distribution system, and wherein the location of the arc fault is determined at a section having a highest amplitude and a lowest phase among the plurality of different sections.

18. The method according to claim 17, further comprising: comparing the highest amplitude of the corresponding segment with the amplitude error threshold; comparing the lowest phase of the corresponding segment with a phase error threshold; as well as The arc fault is determined to be a false positive based on at least one of the highest amplitude being less than the amplitude error threshold or the lowest phase being greater than the phase error threshold.

19. A storage subsystem storing instructions executable by a logic subsystem for: receiving one or more arc fault signals from one or more capacitive arc fault sensors of a plurality of capacitive arc fault sensors electrically connected to a plurality of different sections of a power distribution system, wherein: Each capacitive arc fault sensor of the plurality of capacitive arc fault sensors is configured to output an arc fault signal based at least on detecting a high frequency current generated from capacitive coupling with an arc; as well as Based at least on the one or more arc fault signals, a location of an arc fault in the power distribution system is determined.

20. The storage subsystem of claim 19, wherein: The instructions are also executable by the logic subsystem to: receiving a plurality of arc fault signals from the plurality of capacitive arc fault sensors; as well as The location of the arc fault is determined based at least on a difference in amplitudes of the plurality of arc fault signals, a difference in arrival times of the plurality of arc fault signals, and / or a difference in phases of the plurality of arc fault signals.

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