Systems and methods for fault protection

Abstract

This document describes systems and methods for fault protection. An electrical power system architecture for an aircraft includes at least one power source, at least one electrical load, and a power distribution system connecting the at least one power source to the at least one electrical load. The power distribution system is grounded to the aircraft's electrical ground via a high-impedance grounding circuit, and multiple protection devices are electrically coupled upstream and downstream of the high-impedance grounding circuit. In some methods, the electrical power system architecture includes a fault detection circuit configured to detect faults and a controller for selectively opening or closing multiple protection devices based on the detected fault. In some methods, an electrical wiring interconnection system separates the positive and negative power lines of the power distribution system to reduce line-to-line faults.

Description

Technical Field

[0001] These teachings generally concern electrical power distribution systems, and more specifically, fault protection within power distribution systems. Background Technology

[0002] Aircraft electrical power systems support various onboard functions and operations. These systems typically include distribution systems that allocate electrical power from power sources and electrical loads. Modern electrical systems may operate at higher voltages and currents, which can increase the risk of failure and amplify the impact of such failures. Therefore, architectures designed to increase the fault tolerance of aircraft electrical power systems are desirable. Attached Figure Description

[0003] By providing the systems and methods for fault protection described in the following detailed description, especially when studied in conjunction with the accompanying drawings, various needs are at least partially met. A complete and feasible disclosure of the invention (including its preferred mode) is set forth in the specification with reference to the accompanying drawings, in which: Figure 1 Electrical system architectures based on various embodiments of these teachings are depicted; Figure 2 Power distribution systems based on various embodiments of these teachings are depicted; Figure 3 Circuit diagrams depicting high-impedance grounding paths according to various embodiments of these teachings are provided. Figures 4A-4B Electrical system architectures based on various embodiments of these teachings are depicted; Figures 5A-5D Electrical system architectures based on various embodiments of these teachings are depicted; Figure 6 Flowcharts depicting various embodiments of methods for detecting ground faults based on these teachings are provided; and Figure 7 A flowchart is depicted illustrating various embodiments of these teachings for responding to faults in the electrical power distribution network of an aircraft.

[0004] The elements in the accompanying drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size and / or relative positioning of some elements in the drawings may be exaggerated relative to other elements to aid in understanding the various embodiments of this teaching. Furthermore, common but well-known elements that are useful or necessary in commercially viable embodiments are generally not depicted to facilitate a clearer understanding of these different embodiments of this teaching. Certain actions and / or steps may be described or depicted in a specific sequence of occurrence, and those skilled in the art will understand that such specificity regarding the sequence is not actually necessary. Detailed Implementation

[0005] The method presented in this paper provides an architecture and protection strategy for protecting the power distribution system deployed in the electrical power system of an aircraft. In these aspects, and as will be described herein, a combination of high-impedance grounding schemes, Electrical Wiring Interconnection System (EWIS) strategies, and control systems is used to prevent, detect, and isolate faults during short-circuit events.

[0006] Traditionally, aircraft power systems use a TN-CS (4-wire) grounding system, where the low-voltage side of the power supply and the electrical load are grounded to the aircraft chassis. For high-voltage, high-current aircraft applications, the TN-CS (4-wire) system may be unsuitable due to the high current and fault energy generated during a fault. Furthermore, a TN-CS system grounded to the fuselage may not be suitable for carbon fiber reinforced polymer (CFRP) skins, as the high resistance of CFRP may prevent fault detection, and fault current flowing through the CFRP may cause it to overheat and degrade.

[0007] Advantageously, the methods described herein provide an architecture and protection strategy designed for high-voltage, high-current aircraft applications, including CFRP aircraft. High-impedance grounding schemes reduce fault current in the event of line-to-ground faults, making any line-to-ground fault a low-energy fault. Therefore, high-impedance grounding schemes allow aircraft manufacturers to reduce the separation distance between aircraft electrical systems and other components (e.g., fuel lines), as no fault will occur upon contact. Furthermore, the Electrical Wiring Interconnection System (EWIS) described herein separates positive and negative power lines to mitigate the presence and area where line-to-line faults might occur. This can thus reduce the overall armor requirements of the aircraft, resulting in weight reduction and cost reduction.

[0008] In many of these embodiments, the electrical power system architecture includes at least one power source, at least one electrical load, and a power distribution system. The power distribution system connects the at least one power source to the at least one electrical load and includes a positive power line and a negative power line. The electrical power system architecture also includes a high-impedance grounding path connecting the power distribution system and the electrical ground of the aircraft. The electrical power system architecture also includes multiple protection devices coupled to the power distribution system and a fault detection circuit configured to detect faults. A controller is communicatively coupled to the high-impedance grounding circuit, the multiple protection devices, and the fault detection circuit, and is configured to selectively open or close a first subset and / or a second subset of the multiple protection devices based on a detected fault. In some aspects, the multiple protection devices include a first subset of multiple protection devices electrically coupled upstream of the high-impedance grounding circuit and a second subset of multiple protection devices electrically coupled downstream of the high-impedance grounding circuit.

[0009] The terms and expressions used herein have the same general technical meaning as those given to him by one of ordinary skill in the art as set forth above, unless otherwise specified herein. Unless otherwise specifically indicated, the word “or” as used herein should be interpreted as having a separate structure rather than a connected structure. The terms “coupled,” “fixed,” “attached,” etc., refer to direct coupling, fixing, or attachment, as well as indirect coupling, fixing, or attachment through one or more intermediate components or features, unless otherwise stated herein.

[0010] The terms "upstream" and "downstream" refer to the relative directions of current flow. For example, "upstream" refers to the direction from which the current originates, and "downstream" refers to the direction from which the current is received.

[0011] The singular forms “a,” “one,” and “the” include the plural, unless the context clearly indicates otherwise.

[0012] As used herein, approximate language can be applied throughout the specification and claims to modify any representation of quantity that allows for variation without altering the essential function associated with it. Therefore, values ​​modified by one or more terms such as “approximately,” “about,” and “substantially” are not intended to be limited to the specified precise value. In at least some instances, approximate language may correspond to the precision of the instrument used to measure the value or the precision of the method or machine used to construct or manufacture the component and / or system. For example, approximate language may refer to a range of 10%.

[0013] The foregoing and other benefits will become clearer after a thorough review and study of the following detailed description.

[0014] Now refer to the attached diagram, Figure 1This is the electric power system architecture 100 of the aircraft. The aircraft can be configured as an electric or hybrid electric aircraft. The electric power system architecture 100 includes a power supply 102, a conversion unit 104, a power distribution system 106, a high-impedance grounding circuit 108, an inverter unit 110, and an electrical load 112.

[0015] Power source 102 can be any power source that supplies electrical power to the aircraft. In this example, power source 102 can be at least one of a battery, a fuel cell, or a generator. It will be understood that, although... Figure 1 The embodiments depict a single power source, but in other exemplary embodiments, the power system architecture 100 may include any suitable number of power sources (e.g., 2, 3, 4, etc.). The power sources may be a combination of the same or different types of power sources.

[0016] The conversion unit 104 is connected in series with the power supply 102. The conversion unit 104 is configured to match the voltage and power levels between the power supply 102 and the power distribution system 106. Specifically, the conversion unit 104 may include one or more converters for converting received electrical power from, for example, alternating current (AC) or direct current (DC) power.

[0017] Inverter unit 110 is connected in series with electrical load 112. Inverter unit 110 is configured to regulate the voltage and power levels between power distribution system 106 and electrical load 112. Specifically, inverter unit 110 may include one or more inverters for converting received electrical power from, for example, DC power to AC power.

[0018] Electrical load 112 can be any system or component in the aircraft that is supplied with electrical power by power source 102. Electrical load 112 can be a passive or active electrical load. In the example, the electrical load can be a pump, heating element, electrical distribution device, or motor. In one example, the motor is configured as an electric motor in a propulsion system configured to receive electrical power and convert it into mechanical rotational force to drive a fan and generate thrust. It will be understood that, although... Figure 1 The embodiments depict a single electrical load, but in other exemplary embodiments, the power system architecture 100 may include any suitable number of electrical loads (e.g., 2, 3, 4, etc.). The electrical loads may be a combination of the same type or different types of electrical loads.

[0019] Power distribution system 106 is operatively coupled between power supply 102 and electrical load 112. Specifically, power supply 102 and conversion unit 104 are operatively coupled to inverter unit 110 and electrical load 112 via power distribution system 106. Electrical power supplied by power supply 102 is converted by conversion unit 104 and supplied to power distribution system 106. Furthermore, electrical power supplied by power distribution system 106 is converted by inverter unit 110 and supplied to electrical load 112.

[0020] The power distribution system 106 includes a positive power line 114 (i.e., positive terminal) and a negative power line 116 (i.e., negative terminal) coupling the power source 102 to the electrical load 112. The positive power line 114 and the negative power line 116 are each at a potential relative to the electrical ground 118, denoted as V. + and V - As used herein, “power line” refers to any suitable mechanism or component used to conduct current, including but not limited to conductive cables, power rails, or other conductive paths.

[0021] The electrical power system architecture 100 is grounded via a high-impedance grounding circuit 108. Specifically, the power distribution system 106 is grounded to the aircraft's electrical ground 118 via the high-impedance grounding circuit 108. In other words, the positive power line 114 and the negative power line 116 are connected to the aircraft's electrical ground 118 via the high-impedance grounding circuit 108. As will be described more fully below, the high-impedance grounding circuit 108 provides, as Figure 2 The high-impedance components shown make any line-to-ground (LG) fault a low-energy fault. Advantageously, the separation distance between the electrical power system architecture 100 and other aircraft systems (e.g., fuel lines) can be reduced because no fault will occur upon contact. It should be understood that the electrical power system architecture 100 is shown at an illustrative level and may include other aspects and components not necessary for understanding this subject matter.

[0022] refer to Figure 2 , showed Figure 1 A schematic diagram of the power distribution system 106. The power distribution system 106 also includes a first high-impedance grounding path 120, a second high-impedance grounding path 122, multiple protection devices 124, a fault detection circuit 126, and a controller 128.

[0023] As described above, the power distribution system 106 is grounded to the aircraft's electrical ground 118 via a high-impedance grounding circuit 108. The high-impedance grounding circuit 108 includes a first high-impedance grounding path 120 connected between the positive power line 114 and the electrical ground 118, and a second high-impedance grounding path 122 connected between the negative power line 116 and the electrical ground 118. The first high-impedance grounding path 120 and the second high-impedance grounding path 122 are connected in parallel.

[0024] The first high-impedance ground path 120 includes a first high-impedance component 130, and the second high-impedance ground path 122 includes a second high-impedance component 132. High-impedance components can be selected to mitigate transient voltage and current disturbances caused by faults. In the example, one of the first high-impedance component 130 or the second high-impedance component 132 may include a first resistor (R1), and the other of the first high-impedance component 130 or the second high-impedance component 132 may include a damper circuit 204, such as... Figure 3 As shown in the diagram. The damper circuit may include a resistor (R2) connected in series with the capacitor (C1). The resistance value of the first resistor (R1) may be selected based on the rated current capacity of the resistor (R1). The resistance value of the second resistor (R2) and the capacitance value of the capacitor (C1) may be selected based on the rate of damping transients under fault conditions. In other examples, both the first high-impedance component 130 and the second high-impedance component 132 may include resistors.

[0025] The plurality of protection devices 124 includes protection devices 134-140 that are operationally grounded to the positive power line 114 and the negative power line 116. The plurality of protection devices 124 includes a first subset of protection devices upstream of the high-impedance grounding circuit 108 and a second subset of protection devices downstream of the high-impedance grounding circuit 108. Specifically, the first subset of protection devices includes a first protection device 134 operationally grounded to the positive power line 114 upstream of the first high-impedance grounding path 120, and a second protection device 136 operationally grounded to the negative power line 116 upstream of the second high-impedance grounding path 122. The second subset of protection devices includes a third protection device 138 operationally grounded to the positive power line 114 downstream of the first high-impedance grounding path 120, and a fourth protection device 140 operationally grounded to the negative power line 116 downstream of the second high-impedance grounding path 122. Protection devices 134-140 detect abnormal conditions, interrupt and / or isolate overcurrent, short-circuit and fault events in the power distribution system 106, and may include electromechanical circuit breakers, contactors, relays, solid-state power controllers (SSPCs), etc. More specifically, in an exemplary embodiment, the first protection device 134 and the second protection device 136 may be fast-acting protection devices (e.g., SSPCs). The second protection device 136 and the fourth protection device 140 may be fast-acting protection devices (e.g., SSPCs) or slow-acting protection devices (e.g., contactors). It is generally contemplated that any various types of electrical or electronic or other types of protection devices may be used. It will be understood that, although... Figure 2 Four protection devices are disclosed, but the power distribution system may include any suitable number of protection devices (e.g., 6, 8, 10, 12, etc.).

[0026] Fault detection circuit 126 is used to detect faults in power distribution system 106. Fault detection circuit 126 is operatively connected to high-impedance grounding circuit 108 and electrical ground 118. Fault detection circuit 126 may include a voltage sensor or impedance monitor for providing line-to-ground fault detection.

[0027] The power distribution system 106 also includes a current sensor. The current sensor can be any type of current sensing device and may include a separate current sensing monitor or sensor that can be provided to any of the protection devices 134-140 to detect overcurrent conditions and determine the direction of the overcurrent for providing line-to-line fault detection. In this example, the current sensing device may be integrated into the controller 128.

[0028] Controller 128 may be any microcontroller, computer, or processor-based device having a processor, memory, and programmable input / output peripherals, and is generally designed to manage the operation of other components and devices. It is also understood to include common auxiliary devices, including memory, transceivers for communicating with other components and devices, etc. These architectural options are known and understood in the art. Controller 128 may be configured (e.g., by using a corresponding program stored in memory, as will be well understood by those skilled in the art) to perform one or more steps, actions, and / or functions (e.g., predetermined commands) described herein. Controller 128 may include memory containing computer instructions (e.g., predetermined commands) that implement any of the functions described herein.

[0029] Controller 128 is configured to acquire voltage or impedance readings from fault detection circuit 126 and current readings from a current sensor, and use one or more of these readings to determine when to activate one or more of a plurality of protection devices 124. Controller 128 may actuate one or more of the plurality of protection devices 124 based on fault conditions including line-to-line faults or line-to-ground faults. In one example, the controller may be configured to send a trip signal to selectively activate a first subset of the plurality of protection devices 134, 136 or a second subset of the plurality of protection devices 138, 134 when a change in grounding impedance, such as that measured by an impedance monitor, of a first or second high-impedance ground path 120, 122, or a change in voltage, such as that measured by a voltage detector, between the positive terminal (i.e., positive power line 114) and electrical ground 118 and the negative terminal (i.e., negative power line 116) and electrical ground 118 exceeds a given value. In another example, the controller can be configured to send a trip signal to selectively actuate a first subset of a plurality of protection devices 134, 136 or a second subset of a plurality of protection devices 138, 134 when the current, as measured by a current sensor, exceeds a given value.

[0030] In some embodiments, the power distribution system 106 includes a power distribution box that houses (encapsulates) electrical and / or electronic components, including a high-impedance grounding circuit 108, multiple protection devices 124, a fault detection circuit 126, and a controller 128. The power distribution box includes a power input coupled to a power source 102 and a power output coupled to an electrical load 112. The power distribution box can also be coupled to multiple systems and distribute electrical power to multiple systems. In other words, the power distribution box can be operatively coupled to one or more power sources and one or more electrical loads.

[0031] In some embodiments, the power distribution system 106 further includes an Electrical Wiring Interconnection System (EWIS) configured to separate the positive power line 114 and the negative power line 116 for line-to-line fault protection, indicated by arrow S1. The positive power line 114 and the negative power line 116 are arranged and wired through the power distribution system 106 such that they are separated. In an example, the positive power line 114 and the negative power line 116, located along an aircraft structure (e.g., fuselage, wing, etc.), are physically separated by the EWIS. In some examples, the EWIS may be integrated into a power distribution box, such that the positive power line 114 and the negative power line 116 are separated within the power distribution box.

[0032] Now for reference Figure 3 A high-impedance ground path 200 is provided according to some embodiments. The exemplary high-impedance ground path 200 may be incorporated into the exemplary high-impedance ground circuit 108, and specifically, as... Figure 2 The first and second high-impedance grounding paths 120 and 122 are depicted. High-impedance grounding path 200 includes two parallel branches with a first resistor 202, which are electrically connected in parallel to a damper circuit 204. The damper circuit 204 includes a second resistor 206 electrically connected in series with a capacitor 308. The resistance value of the first resistor 202 can be selected based on the rated current capacity of the resistor (R1). The resistance value of the second resistor 206 and the capacitance value of the capacitor 208 can be selected based on the rate of damping transients under fault conditions. In this way, high-impedance grounding path 200 reduces the line-to-ground fault energy, making any line-to-ground fault a lower-energy fault under fault conditions.

[0033] Now for reference Figure 4A This provides a solution for line-to-line faults downstream of the high-impedance grounding circuit 108. Figure 1 An example of a circuit. Figure 4A The circuit has the same Figure 1 The circuit uses the same components, and these descriptions will not be repeated here.

[0034] like Figure 4AAs shown, a line-to-line fault 150 occurs. In this case, the fault current 152 will flow from the power source 102 to the electrical load 112 through the positive power line 114, and then return to the power source via the negative power line 116. As a result, as... Figure 3 The controller 128 shown actuates the third protection device 138 and the fourth protection device 140. Actuation may have occurred because the current sensed by the current sensor (i.e., the fault current 152) exceeds a predetermined threshold. Due to the determined direction of the fault current 152, the third protection device 138 and the fourth protection device 140 are actuated. The ground path is not in the fault current path, but a voltage and current drop may occur. In some forms, the controller 128 may actuate the third protection device 138 to stop the fault current.

[0035] Now for reference Figure 4B This provides a solution for line-to-line faults upstream of the high-impedance grounding circuit 108. Figure 1 An example of a circuit. Figure 4B The circuit has the same Figure 1 The circuit uses the same components, and these descriptions will not be repeated here.

[0036] like Figure 4B As shown, a line-to-line fault 154 occurs. In this case, fault current 156 will flow from electrical load 112 to power source 102 via the positive power line and return to electrical load via the negative power line. As a result, controller 128 actuates first protection device 134 and second protection device 136. Actuation may have occurred because the current sensed by the current sensor (i.e., fault current 156) exceeds a predetermined threshold. Due to the determined direction of fault current 156, first protection device 134 and second protection device 136 are actuated. The ground path is not in the fault current path, but may experience a voltage and current drop. In some forms, controller 128 may actuate first protection device 134 to stop the fault current.

[0037] Now for reference Figure 5A This provides a solution for line-to-ground faults downstream of the high-impedance grounding circuit 108. Figure 1 An example of a circuit. Figure 5A The circuit has the same Figure 1 The circuit uses the same components, and these descriptions will not be repeated here.

[0038] like Figure 5AAs shown, a line-to-ground fault 160 occurs. In this case, the fault area 162 includes a first protection device 134, a second protection device 136, an electrical ground 118, and a second high-impedance grounding path 122. The fault current 164 flows through the second high-impedance grounding path 122, which connects the negative power line 116 and the electrical ground 118. As a result, the controller 128 actuates the third protection device 138 and the fourth protection device 140 to isolate the fault area 162. Actuation may occur due to changes in the grounding impedance of the first or second high-impedance grounding paths 120, 122, or voltage changes between the positive terminal (i.e., the positive power line 114) and the electrical ground 118 and the negative terminal (i.e., the negative power line 116) and the electrical ground 118. After actuation, once the fault area 162 is isolated, the DC voltage is restored, and electrical power flows through the reconfigured power grid at a newly established balanced operating point.

[0039] Now for reference Figure 5B This provides a solution for line-to-ground faults downstream of the high-impedance grounding circuit 108. Figure 1 An example of a circuit. Figure 5B The circuit has the same Figure 1 The circuit uses the same components, and these descriptions will not be repeated here.

[0040] like Figure 5B As shown, a line-to-ground fault 166 has occurred. In this case, the fault area 168 includes a first protection device 134, a second protection device 136, an electrical ground 118, and a second high-impedance grounding path 122. A fault current 170 flows through the first high-impedance grounding path 120 connecting the positive power line 114 and the electrical ground 118. As a result, the controller 128 actuates the third protection device 138 and the fourth protection device 140 to isolate the fault area 168. Actuation may occur due to changes in the grounding impedance of the first or second high-impedance grounding paths 120, 122, or voltage changes between the positive terminal (i.e., the positive power line 114) and the electrical ground 118 and the negative terminal (i.e., the negative power line 116) and the electrical ground 118. After actuation, once the fault area 168 is isolated, the DC voltage is restored, and electrical power flows through the reconfigured grid at a newly established balanced operating point.

[0041] Now for reference Figure 5C This provides a solution for line-to-ground faults upstream of the high-impedance grounding circuit 108. Figure 1 An example of a circuit. Figure 5C The circuit has the same Figure 1 The circuit uses the same components, and these descriptions will not be repeated here.

[0042] like Figure 5CAs shown, a line-to-ground fault 172 has occurred. In this case, the fault area 174 includes a third protection device 138, a fourth protection device 140, an electrical ground 118, and a second high-impedance grounding path 122. A fault current 176 flows through the second high-impedance grounding path 122, which connects the negative power line 116 and the electrical ground 118. As a result, the controller 128 actuates the first protection device 134 and the second protection device 136 to isolate the fault area 174. Actuation may occur due to changes in the grounding impedance of the first or second high-impedance grounding paths 120, 122, or voltage changes between the positive terminal (i.e., the positive power line 114) and the electrical ground 118, and between the negative terminal (i.e., the negative power line 116) and the electrical ground 118. After actuation, once the fault area 174 is isolated, the DC voltage is restored, and electrical power flows through the reconfigured grid at a newly established balanced operating point.

[0043] Now for reference Figure 5D This provides a solution for line-to-ground faults upstream of the high-impedance grounding circuit 108. Figure 1 An example of a circuit. Figure 5D The circuit has the same Figure 1 The circuit uses the same components, and these descriptions will not be repeated here.

[0044] like Figure 5D As shown, a line-to-ground fault 178 has occurred. In this case, the fault area 180 includes a third protection device 138, a fourth protection device 140, an electrical ground 118, and a first high-impedance grounding path 120. A fault current 182 flows through the first high-impedance grounding path 120, which connects the negative power line 116 and the electrical ground 118. As a result, the controller 128 actuates the first protection device 134 and the second protection device 136 to isolate the fault area 180. Actuation may occur due to changes in the grounding impedance of the first or second high-impedance grounding paths 120, 122, or voltage changes between the positive terminal (i.e., the positive power line 114) and the electrical ground 118, and between the negative terminal (i.e., the negative power line 116) and the electrical ground 118. After actuation, once the fault area 180 is isolated, the DC voltage is restored, and electrical power flows through the reconfigured grid at a newly established balanced operating point.

[0045] It should be understood that, despite Figures 5A-5D In the embodiments, the first protection device 134 and the second protection device 136, or the third protection device 138 and the fourth protection device 140, are activated respectively. However, the controller 128 can activate any combination of protection devices based on power supply and electrical load priorities. In this way, protection devices 134-140 electrically connected to the power supply and loads with lower priority will be activated first. After activation, if the fault area is not isolated, other protection devices 134-140 will be activated.

[0046] refer to Figure 6 A process 600 for detecting ground faults according to some embodiments is provided. (See also...) Figure 1 and Figure 2 The fault detection circuit 126 and the controller 128 can utilize process 600.

[0047] At box 602, measure the first voltage signal (V) between the positive terminal (i.e., positive power line 114) and electrical ground. + The second voltage signal (V) between the negative terminal (i.e., negative power line 116) and electrical ground. - It is generally assumed that a voltage sensor will be used to measure the first voltage signal (V). + ) and second voltage signal (V - The voltage sensor is operatively coupled to the controller.

[0048] At box 604, the first voltage signal (V) + ) and second voltage signal (V - The signals are processed to separate noise and transient effects, and then compared to determine the two signals V. + V - The degree of symmetry between the two signals V. + V - If the difference between the values ​​exceeds a predetermined threshold, the controller triggers a predetermined action. This measurement may indicate the presence of a line-to-ground fault. It is generally assumed that when no line-to-ground fault is detected, the first voltage signal (V...)... + ) and second voltage signal (V - It is basically equal to that of electrical grounding.

[0049] At box 606, when two signals V + V - When the difference between the two exceeds a predetermined threshold, a trip signal is transmitted to selectively open one or more of the multiple protection devices.

[0050] refer to Figure 7 A method 700 is provided, according to some embodiments, for responding to a fault in the electrical power distribution network of an aircraft. Method 700 can be compared with the above-mentioned reference. Figure 1 The described power system architecture 100 is used together and includes a power distribution system grounded through a high-impedance grounding circuit and multiple protection devices.

[0051] At box 702, current and voltage measurements are received. In some forms, a current measurement is received from at least one current sensor, and a voltage measurement is received from at least one voltage sensor. The voltage measurement includes a first voltage signal (V) between the positive terminal (i.e., the positive power line) and electrical ground. +The second voltage signal (V) between the negative terminal (i.e., the negative power line) and the electrical ground. - It is typically envisioned that current is measured from at least one current sensor and voltage is measured from at least one voltage sensor, both of which are operatively coupled to the controller. In some forms, the current sensor may be integrated into the controller.

[0052] At box 704, a fault state associated with the power distribution network is determined based on current and / or voltage measurements. The current and / or voltage measurements may indicate no fault, line-to-line fault, or line-to-ground fault. The controller is configured to determine a line-to-line fault based on a comparison between the current measurement and a predetermined threshold, and is configured to determine a line-to-line fault based on a first voltage signal (V). + ) and second voltage signal (V - A line-to-ground fault is identified when the difference between the two values ​​exceeds a predetermined threshold. In some forms, the controller is configured to identify line-to-ground faults based on the varying ground impedance of a high-impedance grounding circuit.

[0053] At block 706, when the fault condition indicates a line-to-line fault or a line-to-ground fault, a trip signal is transmitted to selectively open or close a subset of multiple protection devices. In some embodiments, the trip signal is transmitted to a subset of multiple protection devices based on the detected fault region. In other embodiments, the trip signal is transmitted to a subset of multiple protection devices based on a predetermined priority order. In some forms, the predetermined priority order may include power supply and electrical load priorities. The trip signal may be transmitted to a subset of multiple protection devices that are in electrical communication with the power supply or an electrical load with a lower priority.

[0054] In some embodiments, after transmitting a trip signal, a second fault state associated with the power distribution network is determined. If the fault state (i.e., line-to-line or line-to-ground) is not removed, a second trip signal is transmitted to selectively open or close a second subset of the plurality of protection devices, different from the first subset of the plurality of protection devices. Furthermore, process 900 is generally envisioned to also include the above references. Figures 1 to 6 The additional operations and actions described.

[0055] Other aspects of this disclosure are provided by the subject matter of the following provisions: An electrical power system architecture for an aircraft includes: at least one power source; at least one electrical load; a power distribution system electrically coupling the at least one power source to the at least one electrical load, the power distribution system including a positive power line and a negative power line; a high-impedance grounding circuit connecting the power distribution system and an electrical ground of the aircraft; a plurality of protection devices coupled to the power distribution system, wherein a first subset of the plurality of protection devices is electrically coupled upstream of the high-impedance grounding circuit, and a second subset of the plurality of protection devices is electrically coupled downstream of the high-impedance grounding circuit; a fault detection circuit configured to detect faults; and a controller communicatively coupled to the high-impedance grounding circuit, the plurality of protection devices, and the fault detection circuit, the controller being configured to selectively open or close the first subset and / or the second subset of the plurality of protection devices based on a detected fault.

[0056] According to any of the foregoing provisions, the power distribution system further includes a power distribution box, the power distribution box including a power input coupled to the at least one power source and a power output coupled to the at least one electrical load, and wherein the high-impedance grounding circuit, the plurality of protection devices and the fault detection circuit are encapsulated in the power distribution box.

[0057] According to any of the foregoing provisions, the power system architecture includes a first high-impedance grounding path connected between the positive line and the electrical ground and a second high-impedance grounding path connected between the negative line and the electrical ground, and wherein the first high-impedance grounding path and the second high-impedance grounding path include a first resistor connected in electrical parallel with the damper circuit.

[0058] According to any of the foregoing provisions, the power system architecture wherein the high-impedance grounding circuit includes a first high-impedance grounding path connected between the positive line and the electrical ground and a second high-impedance grounding path connected between the negative line and the electrical ground, wherein the first high-impedance grounding path and the second high-impedance grounding path include resistors.

[0059] According to any of the foregoing provisions, the first subset of the plurality of protection devices includes at least one protection device electrically coupled to the positive line of the power distribution system and at least one protection device electrically coupled to the negative line of the power distribution system upstream of the high-impedance grounding circuit; and the second subset of the plurality of protection devices includes at least one protection device electrically coupled to the positive line of the power distribution system and at least one protection device electrically coupled to the negative line of the power distribution system downstream of the high-impedance grounding circuit.

[0060] According to the power system architecture described in any of the foregoing clauses, the first subset and the second subset of the plurality of protection devices include at least one fast-acting protection device.

[0061] According to any of the foregoing provisions, the power system architecture wherein the fault detection circuit includes an impedance monitor or a voltage detector.

[0062] The power system architecture according to any of the foregoing provisions also includes an electrical wiring interconnection system configured to separate the positive and negative lines of the power distribution system.

[0063] According to any of the foregoing provisions, the power system architecture wherein the controller is configured to selectively open a first subset or a second subset of the plurality of protection devices based on a fault region.

[0064] According to any of the foregoing provisions, the power system architecture wherein the controller is configured to selectively open a first subset or a second subset of the plurality of protection devices based on a predetermined priority order.

[0065] According to any of the foregoing provisions, the electric power system architecture includes at least one of a battery, a fuel cell, or a generator; and the at least one electrical load includes at least one of a pump, a motor, a heating element, or an electrical distribution device.

[0066] A protection system for an electrical power distribution network of an aircraft, the electrical power distribution network including one or more power sources connected to one or more electrical loads via a power distribution system, the power distribution system being connected to the electrical ground of the aircraft via a high-impedance grounding circuit, the protection system comprising: an electrical wiring interconnection system separating the positive power lines and negative power lines of the power distribution system to reduce line-to-line faults; a plurality of protection devices coupled to the power distribution system, wherein a first subset of the plurality of protection devices is electrically coupled upstream of the high-impedance grounding circuit, and a second subset of the plurality of protection devices is electrically coupled downstream of the high-impedance grounding circuit; and a ground fault detector operably configured to... A controller is connected to the high-impedance grounding circuit and the electrical ground; and coupled to the power distribution system, the high-impedance grounding circuit, the plurality of protection devices, the ground fault detector, and at least one current sensor, the controller being configured to: receive input from the at least one current sensor and / or the ground fault detector; determine a fault state associated with the electrical power distribution network based on the received input, the fault state including no fault, line-to-line fault, or line-to-ground fault; and when the fault state indicates a line-to-line fault or a line-to-ground fault, send a trip signal to selectively open or close a first subset or a second subset of the plurality of protection devices.

[0067] According to any of the foregoing provisions, the protection system wherein the ground fault detector includes a voltage sensor configured to measure a first voltage value between the positive power line and the electrical ground and a second voltage value between the negative power line and the electrical ground.

[0068] According to any of the foregoing provisions, the protection system wherein the controller is configured to: receive the input including a measured first voltage value and a second voltage value, determine a line-to-ground fault based on the difference between the measured first voltage value and the second voltage value, and send the trip signal to selectively open a first subset or a second subset of the plurality of protection devices when the difference between the first voltage value and the second voltage value exceeds a predetermined threshold.

[0069] According to any of the foregoing provisions, the protection system wherein the controller is further configured to: send the trip signal to selectively open or close a first subset or a second subset of the plurality of protection devices, determine whether the line-to-ground fault has been removed; and when the line-to-ground fault has not been removed, send the trip signal to selectively open or close another of the first subset or the second subset of the plurality of protection devices.

[0070] According to any of the foregoing provisions, the protection system wherein the controller is configured to: receive an input including a current measurement from the at least one current sensor, and determine a line-to-line fault based on a comparison between the current measurement and a predetermined threshold; and when the current measurement exceeds the predetermined threshold, send the trip signal to selectively open a first subset and / or a second subset of the plurality of protection devices.

[0071] According to any of the foregoing provisions, the protection system wherein the controller is further configured to send the trip signal to selectively open or close the first subset or the second subset of the plurality of protection devices based on a predetermined priority order.

[0072] According to any of the foregoing provisions, the protection system wherein the controller is further configured to send the trip signal to selectively open or close the first subset or the second subset of the plurality of protection devices based on a predetermined command.

[0073] The protection system according to any of the foregoing provisions, wherein the first subset and the second subset of the plurality of protection devices include at least one fast-acting protection device and at least one slow-acting protection device.

[0074] A method for responding to a fault in an aircraft's electrical power distribution network, the electrical power distribution network including a power distribution system grounded via a high-impedance grounding circuit and a plurality of protection devices, the method comprising: receiving a current measurement from at least one current sensor and / or a voltage measurement from at least one voltage sensor, wherein the voltage measurement includes a first voltage value between a positive line and an electrical ground and a second voltage value between a negative line and ground; determining a fault state associated with the electrical power distribution network based on the current measurement and / or the voltage measurement, the fault state including no fault, line-to-line fault, or line-to-ground fault; and when the fault state indicates a line-to-line fault or a line-to-ground fault, sending a trip signal to selectively open or close a first subset or a second subset of the plurality of protection devices; wherein the fault state indicates a line-to-line fault when the current measurement exceeds a predetermined threshold; and wherein the fault state indicates a line-to-ground fault when the difference between the first voltage value and the second voltage value of the voltage measurement exceeds a predetermined threshold.

Claims

1. An electric power system architecture for an aircraft, the electric power system architecture comprising: At least one power source; At least one electrical load; A power distribution system that electrically couples the at least one power source to the at least one electrical load, the power distribution system comprising a positive power line and a negative power line; A high-impedance grounding circuit connected between the power distribution system and the electrical ground of the aircraft; Multiple protection devices coupled to the power distribution system, wherein a first subset of the multiple protection devices is electrically coupled upstream of the high-impedance grounding circuit, and a second subset of the multiple protection devices is electrically coupled downstream of the high-impedance grounding circuit; A fault detection circuit, configured to detect faults; as well as A controller communicatively coupled to the high-impedance grounding circuit, the plurality of protection devices, and the fault detection circuit, the controller being configured to selectively open or close a first subset and / or a second subset of the plurality of protection devices based on a detected fault.

2. The electrical power system architecture of claim 1, wherein, The power distribution system further includes a power distribution box, which includes a power input coupled to the at least one power source and a power output coupled to the at least one electrical load, wherein the high-impedance grounding circuit, the plurality of protection devices and the fault detection circuit are encapsulated in the power distribution box.

3. The electrical power system architecture of claim 1, wherein, The high-impedance grounding circuit includes a first high-impedance grounding path connected between the positive power line and the electrical ground and a second high-impedance grounding path connected between the negative power line and the electrical ground, wherein the first high-impedance grounding path and the second high-impedance grounding path include a first resistor electrically connected in parallel with the damper circuit.

4. The electrical power system architecture of claim 1, wherein, The high-impedance grounding circuit includes a first high-impedance grounding path connected between the positive power line and the electrical ground, and a second high-impedance grounding path connected between the negative power line and the electrical ground, wherein the first high-impedance grounding path and the second high-impedance grounding path include resistors.

5. The electric power system architecture according to claim 1, wherein The first subset of the plurality of protection devices includes at least one protection device electrically coupled to the positive power line of the power distribution system and at least one protection device electrically coupled to the negative power line of the power distribution system upstream of the high impedance grounding circuit. and The second subset of the plurality of protection devices includes at least one protection device electrically coupled to the positive power line of the power distribution system and at least one protection device electrically coupled to the negative power line of the power distribution system downstream of the high impedance grounding circuit.

6. The electrical power system architecture of claim 1, wherein, The first subset and the second subset of the plurality of protection devices include at least one fast-acting protection device.

7. The electrical power system architecture of claim 1, wherein, The fault detection circuit includes an impedance monitor or a voltage detector.

8. The power system architecture of claim 1 further includes an electrical wiring interconnection system configured to separate the positive power lines and negative power lines of the power distribution system.

9. The electrical power system architecture of claim 1, wherein, The controller is configured to selectively open the first subset or the second subset of the plurality of protection devices based on a fault zone.

10. The electrical power system architecture of claim 1, wherein, The controller is configured to selectively open the first subset or the second subset of the plurality of protection devices based on a predetermined priority order.

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