Power distribution system

Abstract

A power distribution system may include a power source, a power distribution unit, and at least one electrical load supplied by the power distribution unit. A detection circuit may be utilized in the power distribution system to sense or detect the occurrence of an electrical fault within a power or electrical unit.

Description

[0001] This application is a divisional application of the invention patent application with application number 201910624402.1 filed on July 11, 2019 and invention name “Power Distribution System”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of United Kingdom Patent Application No. 1820343.0 filed on December 13, 2018, which is incorporated herein by reference in its entirety. Technical Field

[0004] The present disclosure relates to methods and apparatus for operating a power distribution system, and more particularly to a chassis defining an interior that houses power distribution components. Background Art

[0005] Electrical systems, such as those found in distribution systems, employ electrical buses and miles of wiring for delivering electrical power from a source to electrical loads. In the event of an arc fault or other fault condition, high currents may be transmitted through a normally non-conductive medium, such as air, with unintended consequences for the distribution system at or near the point of the arc fault. Summary of the invention

[0006] In one aspect, the present disclosure relates to a power distribution system, comprising: a chassis defining an inner surface and an interior, and wherein at least a portion of the inner surface includes a conductive detection layer; at least one power distribution component received within the interior and configured to supply power from a power source to an electrical load and disposed within the interior; and a fault detection circuit. The fault detection circuit also includes: a voltage sensor configured to sense a voltage at the conductive detection layer; and a controller module communicatively connected to the voltage sensor and configured to receive the sensed voltage at the conductive detection layer, compare the sensed voltage to a threshold, and when the comparison is satisfied, indicate that an arc event has occurred between at least one power distribution component and the conductive detection layer of the chassis.

[0007] On the other hand, the present disclosure relates to a method for operating a power distribution system, the method comprising sensing a voltage at a conductive detection layer through a voltage sensor, the conductive detection layer being disposed on an inner surface of a chassis housing accommodating at least one power distribution component; receiving the sensed voltage from the voltage sensor through a controller module; comparing the sensed voltage with a threshold voltage value through the controller module; and prohibiting power from being supplied from a power source to at least one power distribution component when the comparison is met. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the attached picture:

[0009] Figure 1is a schematic top view of an aircraft including a power distribution system according to various aspects described herein.

[0010] Figure 2 According to various aspects described herein, a power distribution unit is included Figure 1 Schematic diagram of the power distribution system.

[0011] Figure 3 According to the various aspects described in this article Figure 2 Schematic side view of a power distribution unit.

[0012] Figure 4 During an electrical fault according to the various aspects described herein Figure 3 Schematic side view of a power distribution unit.

[0013] Figure 5 is another electrical fault period according to the various aspects described herein Figure 3 Schematic top view of a power distribution unit.

[0014] Figure 6 is in alternative configurations according to various aspects described herein Figure 3 Schematic bottom view of a portion of a power distribution unit.

[0015] Figure 7 According to the various aspects described herein, Figure 1 Schematic side view of an alternative power distribution unit for use in a power distribution system of FIG. DETAILED DESCRIPTION

[0016] The described aspects of the present disclosure relate to a power distribution system that may be used, for example, in an aircraft. Although the description is primarily directed to a power distribution system for an aircraft, it is also applicable to any environment that uses a power system for transmitting power from a power source to an electrical load.

[0017] Although a "set" of various elements will be described, it should be understood that a "set" may include any number of corresponding elements, including only one element. Also as used herein, although a sensor may be described as "sensing" or "measuring" a corresponding value, sensing or measuring may include determining a value indicative of or associated with the corresponding value, rather than directly sensing or measuring the value itself. The sensed value or measured value may be further provided to other components. For example, the value may be provided to a controller module or processor, and the controller module or processor may perform processing on the value to determine a representative value or electrical characteristic representing the value.

[0018] Connection references (e.g., attach, couple, connect, and link) are to be interpreted broadly and, unless otherwise indicated, may include intermediate members between a collection of elements and relative movement between elements. Thus, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. In a non-limiting example, a connection or disconnection may be selectively configured, connected or connectable to provide, enable, disable, etc., electrical connection between various elements. A non-limiting example power distribution bus connection or disconnection may be enabled or operated by a switch, bus connection logic, or any other connector configured to enable or disable energization of electrical loads downstream of the bus.

[0019] As used herein, a "system" or "controller module" may include at least one processor and memory. Non-limiting examples of memory may include random access memory (RAM), read-only memory (ROM), flash memory, or one or more different types of portable electronic memory, such as disks, DVDs, CD-ROMs, etc., or any suitable combination of these types of memory. The processor may be configured to run any suitable program or executable instructions designed to perform various methods, functions, processing tasks, calculations, etc. to enable or implement the technical operations or operations described herein. The program may include a computer program product, which may include a machine-readable medium for carrying or having machine-executable instructions or data structures stored thereon. Such a machine-readable medium may be any available medium that can be accessed by a general or special-purpose computer or other machine with a processor. Typically, such a computer program may include routines, programs, objects, components, data structures, algorithms, etc., which have the technical effect of performing a specific task or implementing a specific abstract data type.

[0020] As used herein, a controllable switch element or "switch" is an electrical device controllable to switch between a first operating mode in which the switch is "closed" and intended to transfer current from the switch input to the switch output, and a second operating mode in which the switch is "open" and intended to prevent current from being transferred between the switch input and the switch output. In a non-limiting example, a connection or disconnection such as a connection enabled or disabled by a controllable switch element can be selectively configured to provide, enable, disable, etc., electrical connections between various elements.

[0021] Non-limiting aspects of the present disclosure may be implemented in any circuit environment. Non-limiting examples of circuit environments that may include aspects of the present disclosure may include an aircraft power system architecture that is capable of generating power from at least one spool of a turbine engine (preferably a gas turbine engine) and delivering the power to a set of electrical loads via at least one switch. In one example, the switch may be in the form of a solid-state switch (e.g., a solid-state power controller (SSPC) switch device). A non-limiting example of an SSPC may include a high-power switch based on silicon (Si), silicon carbide (SiC), or gallium nitride (GaN). SiC or GaN may be selected based on their solid-state material construction, their ability to handle high voltages and high power levels in a smaller and lighter form factor, and their high-speed switching capabilities to perform electrical operations very quickly. Additional switching devices or additional silicon-based power switches may also be used.

[0022] Additionally, as used herein, "arc," "arcing," "arcing," "arcing event," or "arcing fault" shall refer to the unintentional or undesired conduction of electrical current across a traditionally non-conductive medium (e.g., air). For example, in a non-limiting example, a "parallel arc" may include an arcing event that at least partially connects two points that are intended to be insulated from each other. In another non-limiting example, a "series arc" may include an arcing event in which a conductive medium becomes non-conductive or poorly conductive between two portions of an intended conductive path. Additionally, an arcing event may include an unexpected loss of power, regardless of whether there is an apparent arcing manifestation (e.g., a visible or visually identifiable occurrence). In another non-limiting example, a series arc may include an unexpected impedance. Although "arc fault" and "arc" are described herein for understanding, aspects of the present disclosure are applicable to any electrical fault, including leakage current faults, dielectric faults, arc faults, and the like.

[0023] In addition, as used herein, the term "satisfies" with respect to a threshold value means that the corresponding value is equal to or greater than the threshold value, or is within a threshold range (e.g., within a tolerance). It should be understood that such determinations can be easily changed to be satisfied by positive / negative comparisons or true / false comparisons. In one aspect of the present disclosure, by way of non-limiting example, the threshold value satisfying the aforementioned power characteristic may include falling within a threshold range, such as between 3.9V and 4.1V. Additional thresholds and threshold ranges may be included.

[0024] Electrical faults including arcing may occur in environments where, for example, a physical defect in an electrical connection results in a permanent or temporary loss of transmission capability. In the event of physical separation, the voltage difference between each separated terminal, except for a short separation distance, may allow an arc to strike between the terminals. In environments with vibrations, such as in a moving aircraft, a physical defect in an electrical connection may result in intermittent arcing events as the vibrations disconnect and reconnect the electrical connection at the point of the physical defect. In yet another example, an arc may be caused by (or associated with) a loose terminal connection or a drawn series fault.

[0025] The exemplary drawings are for illustrative purposes only, and the dimensions, positions, orders, and relative sizes reflected in the drawings may vary.

[0026] like Figure 1 As shown in , the aircraft 10 is shown as having at least one gas turbine engine, shown as a left engine system 12 and a right engine system 14. Alternatively, the power system may have fewer or additional engine systems. The left engine system 12 and the right engine system 14 may be substantially identical and may also include at least one power source, such as an electric motor or generator 18. The illustrated aircraft also has a set of power consuming components or electrical loads 20, such as actuator loads, flight critical loads, and non-flight critical loads. The electrical loads 20 are electrically coupled to the at least one generator 18 via a power distribution system, which includes, for example, power transmission lines 22 or buses, and a distribution node 16. It should be understood that Figure 1 The illustrated aspects of are merely one non-limiting example of a power distribution system, and many other possible aspects and configurations other than those illustrated are contemplated by the present disclosure. Figure 1 The numbers and arrangements of the various components depicted in are also non-limiting examples of aspects associated with the present disclosure.

[0027] In the aircraft 10, operating the left engine system 12 and the right engine system 14 provides mechanical energy, which can generally be extracted via a spool to provide driving force to the generator 18. The generator 18 in turn generates electrical power, such as alternating current (AC) or direct current (DC) power, and provides the generated power to the transmission line 22, which transmits the power to the distribution nodes 16 located throughout the aircraft 10. The distribution nodes 16 receive the AC or DC power via the transmission line 22 and can provide switching, power conversion, or distribution management functions as needed to provide the desired power to the electrical loads 20 for load operation.

[0028] Exemplary power distribution management functions may include, but are not limited to, selectively enabling or disabling power delivery to specific electrical loads 20 depending on, for example, the available power distribution supply, the criticality of the functionality of the electrical loads 20, or the aircraft operating mode (e.g., takeoff, cruise, or ground operations). Other management functions may be included. In addition, additional power sources (e.g., emergency power supplies, ram air turbine systems, starters / generators, batteries, etc.) for providing power to the electrical loads 20 may be included and replace or supplement the power source. It should be understood that although one aspect is shown in an aircraft environment, the present disclosure is not limited thereto and has general application to power systems in non-aircraft applications (e.g., other mobile applications and non-mobile industrial, commercial, and residential applications).

[0029] Figure 2 A non-limiting schematic example of a power distribution system 30 of an aircraft 10 is shown. As shown, the power distribution system 30 may include at least one power source, shown as a generator 18, an electrical fault detection circuit 40, a power distribution unit (PDU) 50, and electrical loads 20. The generator 18 may supply any amount or form of electrical power, such as AC or DC, and in a non-limiting example, may supply 270V DC to the power distribution system 30.

[0030] The detection circuit 40 may be positioned “upstream” of the PDU 50, i.e., at a higher electrical potential or closer to the generator 18 than the PDU 50. It should be understood that the power distribution system 30 may include other elements not explicitly shown, such as generators, buses, switches, etc., or combinations thereof. Furthermore, while two detection circuits 40, two power distribution units 50, and two electrical loads 20 are shown, it should be understood that the exemplary power distribution system 30 may include any number of detection circuits 40, PDUs 50, and loads 20. Additionally, conductors 35, such as wires, bus bars, etc., may electrically connect the generator 18 to each of the detection circuits 40, power distribution units 50, and electrical loads 20. While the detection circuit 40 is shown and described upstream of the PDU 50, non-limiting aspects of the present disclosure may be included in which the detection circuit 40 is included in the PDU 50, or in another power distribution system component upstream of the PDU 50.

[0031] Figure 3 The detection circuit 40 and the power distribution unit 50 of the power distribution system 30 are shown in greater detail. In a non-limiting example, the PDU 50 may include a chassis 51 formed of any suitable material for the environment, including aluminum, steel, graphite, or a composite material. The chassis 51 may have an inner surface 52 defining an interior 53 and an outer surface 54 defining an exterior 55. In the example shown, the chassis 51 includes a top wall 56, a bottom wall 57, and opposing side walls 58, 59. Although not shown in FIG. Figure 3, but the chassis 51 may also include a front wall and a rear wall so that the interior 53 may be partially or completely closed. In addition, any one of the walls 56, 57, 58, 59 may be removable to selectively provide an entrance to the interior 53.

[0032] At least a power distribution component, shown as a printed circuit board 60, can be housed within the interior 53 of the chassis 51, for example, as appropriate via a set of tracks or mounting hardware. The printed circuit board 60 is also referred to herein as a "PCB" 60 or a "circuit board" 60. In an alternative example, another power distribution component having contactors and discrete wiring can be used in place of the printed circuit board 60 or in combination with the printed circuit board 60. In a non-limiting example, the PCB 60 can be included in a power switching device or another power source within the chassis 51. In addition, the PCB 60 can include a circuit element, shown as a solid-state switching component (SSPC) 62, which operates to selectively supply power to a downstream electrical load 20 (schematically shown as a single electrical load 20).

[0033] A resistive or high impedance component, shown as resistor 64, can be electrically coupled between the power supply portion of PCB 60 and chassis 51. In the example where PDU 50 supplies AC power, any suitable component with sufficient impedance can be used in place of resistor 64. In the example shown, resistor 64 can be coupled to the inner surface 52 of chassis 51. The outer surface 54 of chassis 51 can be electrically connected to electrical ground 66. Non-limiting aspects of electrical ground 66 may include a common electrical ground, an earth ground, or a common frame such as an aircraft frame. In addition, an exemplary power output 68 of power distribution unit 50 is shown, wherein PDU 50 is connected to electrical load 20 via conductor 35. It will be understood that exemplary power output 68 may represent one or more power outputs from PDU 50. For example, PDU 50 may include multiple power outputs electrically connected to a group of electrical loads 20, and the exemplary power output 68 shown in the figure may represent the total power provided to the group of electrical loads 20. In another example, the exemplary power output 68 may represent the power output of each electrical load 20 in a group of a plurality of electrical loads 20 connected to the PDU 50 .

[0034] The detection circuit 40 can be supplied with power from the generator 18 and electrically coupled to the power distribution unit 50 through the respective first and second conductors 36, 37. The first conductor 36 can be electrically coupled to the inner surface 52 of the chassis 51, and the second conductor 37 can be electrically coupled to the PCB 60 to supply power to the PCB 60. The exemplary detection circuit 40 is shown to include a resistor 41, a voltage sensor 42, an electrical ground 43, a switching element 44, and a controller module 45. In addition, the controller module 45 may also include a processor 46 and a memory 47. The controller module 45 can be configured or adapted to perform a controllable operation, for example, in response to a received signal, data, etc., and generate a control command, a signal, or another enabling or operating function output. For example, as shown, the controller module 45 can be configured or adapted to operably control the switching function of the switching element 44.

[0035] In addition, an exemplary power output 48 of the detection circuit 40 is shown. In this sense, when the switch element 44 is closed, the power supplied by the generator 18 is controllably supplied to the power distribution unit 50 through the detection circuit 40. When the switch element 44 is open, no power is supplied to the PDU 50 via the power output 48.

[0036] Figure 3 An enlarged portion of the chassis 51 is also shown, wherein it is further contemplated in a non-limiting example that at least one wall of the chassis 51 (e.g., the top wall 56) may include a base layer 70, a non-conductive insulating layer 72, and a conductive detection layer 74. The composition of the base layer 70 is not germane to the present disclosure and may include a conductive material. The insulating layer 72 may be formed of any suitable insulating material (e.g., ceramic, polymer, fiberglass, composite material, etc.). In a non-limiting example, the detection layer 74 may be formed of a conductive material (including metal or nano foam). The insulating layer 72 may be located between the base layer 70 and the detection layer 74 and may electrically insulate the detection layer 74 from the base layer 70. In one example, the detection layer 74 may be formed by an additive manufacturing process, such as electrodeposition on the insulating layer 72. In another example, the detection layer 74 may be manufactured or formed, for example, by attachment hardware, before coupling with the insulating layer 72. The detection layer 72 is electrically connected to the first conductor 36.

[0037] It is further contemplated that any or all of the walls 56, 57, 58, 59 may include a layered composition of the enlarged portion 31. In another non-limiting example, only walls that are exposed to power components such as the SSPC 62, or only walls that may be struck by an arcing event, may include a layered composition of the enlarged portion 31. In another non-limiting example, all interior surfaces 52 within the chassis 51 may be coupled to the insulation layer 72 and the detection layer 74.

[0038] In operation, the power supplied by the generator 18 can be utilized by the printed circuit board 60. The resistor 64 coupled to the PCB 60 can bias the detection layer 74 to a non-zero voltage, while the base layer 70 of the top wall 56, which is electrically insulated from the detection layer 74, is grounded via the electrical ground 66. In other words, the resistor 64 can be used as part of a voltage divider completed by the external detection circuit 40. In this way, the detection circuit 40 can sense the output voltage from the detection layer 74 via the first conductor 36 and the voltage sensor 42. The output of the voltage sensor 42 can be provided to the controller module 45 via the communication line 38. The voltage sensor 42 can sense or measure the voltage across the resistor 41 and transmit the sensed or measured voltage to the controller module 45. The voltage sensed or measured by the voltage sensor 42 can be compared by the controller module 45 with a value indicating an electrical fault (e.g., an arc event). When the comparison is met, the controller module can determine that an electrical fault exists. For example, an arc event or an electrical short circuit may change the voltage sensed or measured by the voltage sensor 42 to zero, or may cause the voltage to alternate between zero and non-zero values ​​when an arc event occurs. Based on the sensed voltage, and when the comparison is satisfied, the controller module 45 may determine that an electrical fault, such as an arc event, has occurred in the PDU 50.

[0039] Figure 4 A representative arc fault is shown occurring in a section of a power distribution unit 50. A representative arc fault is shown as a parallel arc fault 80, which may occur when an undesirable or unintended current travels between the PCB 60 and the chassis 51. The specific location of the parallel arc fault 80 shown is only one non-limiting example of an illustrative arc event. Aspects of the present disclosure may be included, wherein arc faults anywhere on an isoelectric conductive connection and the actual location of the arc fault may be detected, identified, and described herein.

[0040] In the example shown, the parallel arc fault 80 is established between the PCB 60 and the detection layer 74 on the chassis top wall 56. In this case, the voltage sensor 42 in the detection circuit 40 can sense the output voltage from the PDU 50, perform the comparison as described above, and determine that the parallel arc fault 80 is occurring.

[0041] In response to determining that an arc event has occurred or is occurring, the controller module 45 can supply, generate or otherwise command the switch element 44 to open, thereby stopping or preventing the supply of power to the PDU 50 and eliminating the arc event. In a non-limiting example, the controller module 45 can also be configured to determine an error or fault based on a change or rate of change of a sensed signal (e.g., a sensed output voltage increases by more than 20V or decreases by more than 5V in less than 1 second). In another example, in response to determining that an arc event has occurred or is occurring, the controller module 45 can also provide an indication to the pilot or operator to warn them that an arc event has occurred. In a non-limiting example, such an indication can be in the form of text or other visual display, or in the form of an audible alarm.

[0042] In one non-limiting example, the generator 18 may provide 270V to the printed circuit board 60, and the predetermined maximum voltage for the detection circuit 40 may be 50V. In the absence of any arc fault, the "nominal" or other standard sensing voltage or signal may be 20V. During the occurrence of a parallel arc fault 80, where a complete path is formed between the detection layer 74 and the PCB 60, the sensing signal of the detection circuit 40 may be 250V. The controller module 45 may sense the output voltage and perform a comparison with a predetermined maximum value. Based on the comparison, the controller module 45 may determine that a parallel arc fault 80 is occurring based on the sensing signal or a change in the sensing signal, and may also open the switching element 44 to prevent power from being supplied to the power distribution unit 50.

[0043] Go to Figure 5 , a power distribution unit 50 is shown in a schematic top view, wherein another representative arc fault is shown as occurring in a section of the PDU 50. In this example, the representative arc fault is shown as a series arc fault 82, which occurs downstream of the power output 48 and upstream of the electrical load 20. In the example shown, the PDU 50 supplies power to the plurality of electrical loads 20 via a corresponding plurality of power outputs 68. Optionally, the PDU 50 may include a corresponding plurality of switches (schematically shown as SSPCs 62) electrically coupled to the plurality of electrical loads 20 to selectively provide power to the electrical loads 20. Additionally, the resistor 64 may optionally be located as far downstream of the power output 48 as possible while still upstream of the SSPCs 62. In another non-limiting example, the resistor 64 may be located downstream of the SSPCs 62. It will be appreciated that positioning the resistor 64 as far downstream of the power output 48 as possible may provide the greatest benefit in detecting the series arc fault 82.

[0044] In addition, although Figure 2The schematic diagram does not show a large conductor 35 length or span between the generator 18 and the PDU 50 or electrical load 20, but in non-limiting aspects of an actual aircraft 10 environment, the conductor 35 length or span between the generator 18 and the PDU 50 or electrical load 20 may be a long distance on the order of meters.

[0045] The series arc fault 82 may occur between a first location 91 and a second location 92 of a conductor 63 in the printed circuit board 60. For example, if a break is created in the conductor 63 between the first location 91 and the second location 92, an arc may occur, as indicated by the series arc fault 82. In this case, in a non-limiting example, the sense signal of the detection circuit 40 may be below a predetermined minimum value, such as a sense signal of 5V, where during normal operation, the predetermined minimum value is 10V, and the “nominal”, standard or expected value is 15V. In another example, due to the series arc fault 82, the sense signal may drop by an amount between 10V and 20V in a time interval of less than 1 second. Upon detecting the sense signal or a change in the sense signal, the controller module 45 may determine that a series arc fault 82 is occurring. The controller module 45 may also open the switch element 44 to prevent power from being supplied to the PDU 50.

[0046] Figure 6 A bottom schematic diagram of a power distribution unit 50 is shown, showing another configuration of a detection layer 74 on the inner surface 52 of the top wall 56. It should be understood that the insulating layer 72 may be located between the detection layer 74 and the base layer 70 (not shown). In addition, for the sake of clarity, the detection circuit 40 has been shown in a simplified form, and it should be understood that all of the components included in the detection circuit 40 described above may also be included in the Figure 6 In the example.

[0047] It is contemplated that the detection layer 74 (and corresponding insulating layer 72) may be arranged on a portion of the inner surface 52 of the chassis 51, such as in a serpentine configuration. In non-limiting examples, other arrangements include square or circular spirals or randomly oriented segments. In addition, while the serpentine detection layer 74 is schematically shown with significant gaps between adjacent segments, it is contemplated that any size, arrangement, or spacing of the detection layer 74 may be utilized. In a non-limiting example, the segments of the detection layer 74 may be separated by a distance of 1 mm or less.

[0048] For example, an arcing event occurring in PCB 60 can quickly generate a large amount of heat in region 84 that overlaps at least a portion of detection layer 74. In some cases, the heat generated is sufficient to deform a localized region of continuous detection layer 74 or cause a break therein. It should also be understood that heating of region 84 may also occur due to resistive heating, such as heating caused by a poor electrical connection or overcurrent in region 84. In this sense, detection layer 74 may include a thermally deformable layer. Additionally, an arcing event may cause heat to be transferred directly to chassis 51 before controller module 45 opens switch element 44.

[0049] In the example shown, a heated area 84 due to an arc is shown on the inner surface 52 of the chassis 51. In an example where sufficient heat is generated in the heated area 84 to cause damage to the inner surface 52, the detection layer 74 in the serpentine configuration may be "broken" or broken so that no current can continue to flow through the detection layer 74. It can be appreciated that the segmented or serpentine detection layer 74 can provide additional protection to the chassis 51 during an arc event by disrupting possible conductive paths along the detection layer 74, as compared to examples utilizing a continuous detection layer 74. For example, such disruption of the conductive path can cause the output voltage sensed by the voltage sensor 42 to drop to zero, in which case the controller module 45 can determine that an arc event has occurred as described above.

[0050] Reference now Figure 7 , showing that it can be used in the power distribution system 30 ( Figure 2 ) is another power distribution unit 150 used in the present invention. The power distribution unit 150 is similar to the power distribution unit 50; therefore, unless otherwise specified, like components will be identified by like numbers increased by 100, and it should be understood that the description of like components of the power distribution unit 50 applies to the power distribution unit 150.

[0051] The PDU 150 may include a chassis 151 having an inner surface 152 defining an interior 153 and an outer surface 154 defining an exterior 155. The chassis 151 also includes a top wall 156, a bottom wall 157, and opposing side walls 158, 159. One difference is that the chassis 151 may be formed of a high impedance material such as a composite material, including a polymeric material or fiberglass.

[0052] A printed circuit board 160 may be housed within the interior 153 of the chassis 151. The PCB 160 may also include a circuit element, shown as SSPC 162, that draws power for operation of the circuit board 160. A resistor 164 may be electrically coupled to the PCB 160 and the interior surface 152 of the chassis 151. Another difference is that a capacitor 165 may also be electrically coupled to the PCB 160 and the interior surface 152, forming a parallel electrical connection with the resistor 164. Additionally, an exemplary power outlet 168 is also shown upstream of the connected electrical load 20. Another difference is that the chassis 151 may be disconnected from electrical ground due to its high impedance material properties.

[0053] Figure 7 An enlarged portion 32 of chassis 151 is further shown, wherein it is further contemplated that at least one wall of chassis 151, such as top wall 156, may include base layer 170 and conductive detection layer 174. Another difference is that due to the high impedance characteristics of base 151, an insulating layer is not required between base layer 170 and detection layer 174.

[0054] The detection circuit 40 may be electrically coupled to the chassis 151 via the first conductor 36 and the second conductor 37. During operation, the detection circuit 40 may sense an output voltage or signal from the PDU 150 and open or close the switch element 144 based on a determination of an arc event as described above. It is contemplated that the addition of the capacitor 165 to the PDU 150 may perform a filtering function for electromagnetic interference from the detection circuit 40 or the printed circuit board 60. It will be appreciated that in examples where conventional aluminum or other conductive materials are used for the chassis, the conductive properties of the material may provide electromagnetic shielding without the need for additional capacitors.

[0055] Various aspects of the present disclosure provide for detection of electrical faults or arc events in a power distribution system. A technical effect is that the above aspects enable detection or confirmation of electrical faults in a circuit and provide an indication or remedy of such a fault. One advantage is that the above aspects provide active detection of arc electrical faults and can selectively supply or withhold power to a distribution unit based on the determination of an arc event. Since arc faults can generate a large amount of heat in a short period of time, rapid detection or repair of such faults can extend the life of components within the power distribution system.

[0056] It will also be appreciated that aspects of the present disclosure provide the ability to detect internal arc faults before they can propagate and affect other electrical systems, including other aircraft systems in an exemplary aircraft environment. Providing a fault signal to an upstream unit or component (e.g., a detection circuit) can allow the affected unit (e.g., a PDU) to be electrically isolated and the electrical fault to stop progressing. In environments utilizing high power or high voltage systems, such electrical isolation can improve operational safety.

[0057] To the extent not yet described, the different features and structures of various aspects can be used in combination, or replaced with each other as needed. A feature not shown in all aspects is not meant to be interpreted as not being so shown, but is done so for the sake of brevity of description. Therefore, various features of different aspects can be mixed and matched as needed to form new aspects, whether or not the new aspects are explicitly described. This disclosure encompasses all combinations or permutations of the features described herein.

[0058] The various features, aspects and advantages of the present disclosure may also be embodied in any permutation of the aspects of the present disclosure, including but not limited to the following technical solutions defined in the enumerated aspects:

[0059] 1. A power distribution system, comprising:

[0060] a chassis defining an inner surface and an interior, and wherein at least a portion of the inner surface includes a conductive detection layer;

[0061] at least one power distribution component received within the interior, configured to supply power from the power source to the electrical load, and disposed within the interior; and

[0062] Fault detection circuit, including:

[0063] a voltage sensor configured to sense a voltage at the conductive detection layer;

[0064] A controller module is communicatively coupled to the voltage sensor and is configured to receive a voltage sensed at the conductive detection layer, to compare the sensed voltage to a threshold value, and when the comparison is satisfied, to indicate that an arc event has occurred between at least one power distribution component and the conductive detection layer of the chassis.

[0065] 2. A power distribution system according to any disclosed aspect, wherein at least one power distribution component is a solid state power controller.

[0066] 3. A power distribution system according to any disclosed aspect, wherein the chassis is adapted to hold a set of circuit boards including at least one power distribution component.

[0067] 4. A power distribution system according to any disclosed aspect, wherein the conductive detection layer is biased to a predetermined non-zero voltage.

[0068] 5. A power distribution system according to any disclosed aspect, wherein the threshold value is a predetermined non-zero voltage.

[0069] 6. A power distribution system according to any disclosed aspect, wherein the conductive detection layer is biased to a predetermined non-zero voltage via an impedance electrically connecting the conductive detection layer to a voltage source.

[0070] 7. The power distribution system of any disclosed aspect, wherein the voltage source is one of a circuit board or at least one power distribution component received within an interior of the chassis.

[0071] 8. A power distribution system according to any disclosed aspect, wherein all interior surfaces include a conductive detection layer.

[0072] 9. The power distribution system according to any disclosed aspect, wherein when the comparison is satisfied, the controller module is further configured to inhibit supply of power from the power source to the at least one power distribution component.

[0073] 10. The power distribution system according to any disclosed aspect, wherein the conductive detection layer may include a conductive layer patterned on at least a portion of the inner surface.

[0074] 11. A power distribution system according to any disclosed aspect, wherein the conductive detection layer comprises a serpentine pattern on at least a portion of the interior surface.

[0075] 12. A power distribution system according to any disclosed aspect, wherein the conductive detection layer comprises a thermally deformable layer.

[0076] 13. A power distribution system according to any disclosed aspect, wherein the thermally deformable layer is selected to deform in response to a local arc event or in response to resistive heating due to current conducted during the arc event, and wherein the deformation changes the sensed voltage at the conductive detection layer.

[0077] 14. A method of operating a power distribution system, the method comprising:

[0078] sensing, by a voltage sensor, a voltage at a conductive detection layer disposed on an inner surface of a chassis accommodating at least one power distribution component;

[0079] receiving a sensed voltage from a voltage sensor via a controller module;

[0080] comparing, by the controller module, the sensed voltage to a threshold voltage value; and

[0081] When the comparison is satisfied, supply of power from the power source to the at least one power distribution component is inhibited.

[0082] 15. The method of any disclosed aspect, further comprising, when the comparison is satisfied, providing an indication that an arc event has occurred between at least one power distribution component and the conductive detection layer of the chassis.

[0083] 16. The method according to any disclosed aspect, further comprising biasing the voltage at the conductive detection layer to a predetermined non-zero voltage.

[0084] 17. The method according to any disclosed aspect, further comprising disposing a conductive detection layer in a geometric pattern on an inner surface of the chassis.

[0085] 18. The method according to any disclosed aspect, wherein the geometric pattern is a serpentine pattern.

[0086] 19. The method according to any disclosed aspect, wherein the conductive detecting layer is a thermally deformable conductive detecting layer.

[0087] 20. The method according to any disclosed aspect also includes selecting a thermally deformable conductive detection layer so that the thermally deformable conductive detection layer deforms in response to a local arc event, or in response to resistive heating caused by current conducted during an electrical fault event, and wherein the deformation changes the sensed voltage at the thermally deformable conductive detection layer.

[0088] This written description uses examples to disclose various aspects of the present disclosure, including the best mode, and also enables those skilled in the art to practice the present disclosure, including making and using any device or system and performing any combined method. The patentable scope of the present disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. These other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A power distribution system (30), characterized in that: include: a chassis (51), the chassis (51) defining an inner surface (52) and an interior (53), and wherein at least a portion of the inner surface (52) includes a conductive detection layer (74); at least one power distribution component received within the interior (53) and configured to supply power from a power source (18) to an electrical load (20); a resistor or high impedance component (64) electrically coupled between a power supply portion of the at least one power distribution component and the chassis (51); and A fault detection circuit (40), the fault detection circuit (40) comprising: a resistor (41), the resistor (41) being electrically coupled between the conductive detection layer (74) and ground; a voltage sensor (42) configured to sense the voltage at the conductive detection layer (74) by sensing or measuring the voltage across the resistor (41); A controller module (45) is communicatively connected to the voltage sensor (42) and is configured to receive the sensed voltage at the conductive detection layer (74), compare the sensed voltage with a threshold value, and, when the comparison is satisfied, indicate that an arc event has occurred between the at least one power distribution component and the conductive detection layer (74) of the chassis.

2. The power distribution system (30) according to claim 1, characterized in that: Wherein the at least one power distribution component is a solid state power controller (62).

3. The power distribution system (30) according to claim 1 or 2, characterized in that: The chassis (51) is adapted to hold a set of circuit boards (60) including the at least one power distribution component.

4. The power distribution system (30) according to any one of claims 1 to 2, characterized in that: The conductive detection layer (74) is biased to a predetermined non-zero voltage.

5. The power distribution system (30) according to any one of claims 1 to 2, characterized in that: The controller module (45) is further configured to inhibit the supply of power from the power source (18) to the at least one power distribution component when the comparison is satisfied.

6. The power distribution system (30) according to any one of claims 1 to 2, characterized in that: The conductive detection layer (74) comprises a conductive layer patterned on at least a portion of the inner surface (52).

7. The power distribution system (30) according to any one of claims 1 to 2, characterized in that: The conductive detection layer (74) comprises a thermally deformable layer.

8. A method of operating a power distribution system (30), characterized in that The method comprises: Sensing a voltage at a conductive detection layer (74) by means of a voltage sensor (42), the conductive detection layer (74) being disposed on an inner surface (52) of a chassis (51) accommodating at least one power distribution component, wherein a resistance or high impedance component (64) is electrically coupled between a power supply portion of the at least one power distribution component and the chassis (51), wherein sensing the voltage at the conductive detection layer (74) by means of the voltage sensor (42) comprises: the voltage sensor (42) sensing or measuring a voltage across a resistor (41), the resistor (41) being electrically coupled between the conductive detection layer (74) and ground; Receiving a sensed voltage from the voltage sensor (42) via a controller module (45); comparing the sensed voltage to a threshold voltage value by the controller module (45); and When the comparison is satisfied, an indication is provided that an arc event has occurred between the at least one power distribution component and the conductive detection layer (74) of the chassis (51).

9. The method according to claim 8, characterized in that Further comprising disabling the supply of power from a power source (18) to the at least one power distribution component when the comparison is satisfied.

10. The method according to claim 8 or 9, characterized in that: Further comprising biasing the voltage at the conductive detection layer (74) to a predetermined non-zero voltage.

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