Abstract: Pre-charge circuitry allows capacitive loads connected to a solid state power controller to be gradually charged up by a PWM, generated with a cycle by cycle current limit, switching a single MOSFET in series with an inductor, before the SSPC is turned on. The pre-charge circuitry may require only three additional components, e.g., a MOSFET, an inductor and a diode, along with a designated MOSFET gate driver.

Abstract: A solid state power controller (SSPC) often contains electronic circuitry which could be damaged or upset by the excessive transient voltages induced by the lightning and SSPC could result in undesirable (or nuisance) trips due to lightning strikes. The present invention is intended to address the “nuisance trip” issue, by relying on the lightning indicative signals to distinguish between the transient current surge due to the lightning strike and that due to the circuit fault in the power distribution channel. The present invention utilizes either the break-down current in a transient voltage suppression (TVS) device, or a voltage signal at the output of the SSPC as the indication of lightning strike, to avoid nuisance trips.

Abstract: Hidden or overlapped peaks may occur when using SSTDR technology to determine ware faults. These hidden/overlapped peaks may cause false negative determinations (no fault) when testing a wire for faults. In one method of the present invention, the symmetrical property of the SSTDR wave envelope is used to resolve hidden/overlapped peaks. In another method of the present invention, the calibrated normalized loop back SSTDR wave envelope may be used to resolve hidden/overlapped peaks.

Abstract: High-power power distribution in an aircraft may use solid state power controller (SSPC) technology. A conventional electromechanical contactor may be used, in series, with a solid state switching device (SSSD) to achieve high-power power distribution. Since the electromechanical contactor does not need to be rated for arc handlings during normal SSPC operation, the electromechanical contactor may be simplified, resulting in cost, weight, volume, and failure rate reductions. The power distribution apparatus and methods of the present invention may be applicable for both alternating current (AC) and direct current (DC) applications and can be modified to form a three phase SSPC.

Abstract: Methods for detecting wet arc faults are based on the direct current (DC) signature analysis and pattern matching pertaining to wet arc characteristics. While magnifying some wet arc fault signatures, it may be found that the wet arc current signal itself resembles a normal current signal in both time and frequency domains. The change in magnitude or high frequency behavior found may not be enough to distinguish a wet arc fault signature from a normal signature. Embodiments of the present invention may look at the magnitude change in the DC content per cycle of the wet arc current signal, which may be more positive in one cycle while, in the next cycle, it may be negative in a relative manner. A particular number of these changes may be determinative of a wet arc fault.

Abstract: A power line communication-based aircraft power distribution system may allow for both power line communication (PLC) technology and spread spectrum time domain reflectometry (SSTDR) technology to be utilized in aircraft power distribution systems to achieve key maintenance functions. Unlike conventional power distribution systems, which may, for example, use only SSTDR for fault detection, the present invention includes a hardware platform that may allow both the PLC and the SSTDR to be utilized in aircraft power distribution systems to achieve key maintenance functions, such as real time wire fault location, and cost and weight savings. Further, unlike conventional power distribution systems, which may only detect and locate damage in feeder conductor wire sections before the power is applied to the load, the power distribution system of the present invention may permit real time wire fault location.

Abstract: A high power solid state power controller packaging system and power panel are disclosed. The high power solid state power controller packaging system includes a plurality of discrete power devices assembled juxtaposed to one another in a row, a fin style heatsink, an input bus bar and an output bus bar, and a circuit card assembly connected to the plurality of discrete power devices for managing power signals among the plurality of discrete power devices. The power panel includes a chassis, a mounting bracket with connector sockets formed in the mounting bracket, and a plurality of high power solid state power control modules modularly mounted in the connector sockets.

Abstract: A contactor may operate to interrupt current in a circuit while the circuit is operating under load. A shunt is provided to by-pass surge power current around contacts to reduce arcing. The shunt includes a solid-state switch that may be operated in a series of pulses during movement of the contacts. The pulse control unit may detect a potential for arcing and then provide for periodic pulsing operation of the shunt. Because the solid-state switch may operate discontinuously, the contactor may be constructed with a switch that is selected on a basis of its pulse rating.

Abstract: A coordinated arc fault protection scheme in a hierarchical power distribution system is disclosed. The methods according to embodiments of the present invention may be considered an “event and time graded” analysis. In event and time based analysis, the number of confirmed arc signature may be monitored with respect to time in the main feeder line as well as the branched feeders. The confirmed arc signature in the branched feeder, as well as in the main feeder, may be captured and time stamped. A trip command may be issued first in the intended branched feeder if the branched feeder experiences a minimum number of events within a given time. During the same time period, the main feeder also monitors similar arcing events. If the tripping of the branched feeder occurs and the main feeder still detects arcing events, the main feeder may be tripped after a certain period of time or a certain number of confirmed arc signature.

Abstract: A high voltage direct current (HVDC) power distribution system comprises at least one power bus; at least one load conductor; and a hybrid contactor for interconnecting the at least one power bus and the at least one load conductor and through which inductive energy passes upon disconnection of the at least one load conductor from the at least one power bus. A first portion of the inductive energy passes through the hybrid contactor as an arc. A second portion of the inductive energy passes through the hybrid contactor as resistively dissipated heat.

Abstract: Methods for detecting wet arc faults are based on the direct current (DC) signature analysis and pattern matching pertaining to wet arc characteristics. While magnifying some wet arc fault signatures, it may be found that the wet arc current signal itself resembles a normal current signal in both time and frequency domains. The change in magnitude or high frequency behavior found may not be enough to distinguish a wet arc fault signature from a normal signature. Embodiments of the present invention may look at the magnitude change in the DC content per cycle of the wet arc current signal, which may be more positive in one cycle while, in the next cycle, it may be negative in a relative manner. A particular number of these changes may be determinative of a wet arc fault.

Abstract: A solid state power controller (SSPC) often contains electronic circuitry which could be damaged or upset by the excessive transient voltages induced by the lightning and SSPC could result in undesirable (or nuisance) trips due to lightning strikes. The present invention is intended to address the “nuisance trip” issue, by relying on the lightning indicative signals to distinguish between the transient current surge due to the lightning strike and that due to the circuit fault in the power distribution channel. The present invention utilizes either the break-down current in a transient voltage suppression (TVS) device, or a voltage signal at the output of the SSPC as the indication of lightning strike, to avoid nuisance trips.

Abstract: A power line communication-based aircraft power distribution system may allow for both power line communication (PLC) technology and spread spectrum time domain reflectometry (SSTDR) technology to be utilized in aircraft power distribution systems to achieve key maintenance functions. Unlike conventional power distribution systems, which may, for example, use only SSTDR for fault detection, the present invention includes a hardware platform that may allow both the PLC and the SSTDR to be utilized in aircraft power distribution systems to achieve key maintenance functions, such as real time wire fault location, and cost and weight savings. Further, unlike conventional power distribution systems, which may only detect and locate damage in feeder conductor wire sections before the power is applied to the load, the power distribution system of the present invention may permit real time wire fault location.

Abstract: The present invention provides an electrical power distribution system that includes a first primary distribution panel (PDP) connected to a first source of electrical power and a second PDP connected to a second source of electrical power. The second PDP is connected to the first PDP by a conductor. A first solid state power controller (SSPC) receives signals corresponding to the flow of current through the first PDP to a load. A second SSPC receives signals corresponding to the flow of current between the first PDP and the second PDP. The first and second SSPC protect the electrical power distribution system from a variety of fault conditions.

Abstract: A contactor may operate to interrupt current in a circuit while the circuit is operating under load. A shunt is provided to by-pass surge power current around contacts to reduce arcing. The shunt includes a solid-state switch that may be operated in a series of pulses during movement of the contacts. The pulse control unit may detect a potential for arcing and then provide for periodic pulsing operation of the shunt. Because the solid-state switch may operate discontinuously, the contactor may be constructed with a switch that is selected on a basis of its pulse rating.

Abstract: A method and apparatus detect arc faults. The method and apparatus may digitally detect current and voltage signals at a master node (111) positioned at a first point in a wiring system (131). At a second point in the wiring system (131), a slave node (122) may digitally detect current and voltage signals. An arc fault that develops between the first and second points in the wiring system (131) may be detected by comparing the current signals from the master node (111) and from the slave node (122), and comparing the voltage signals from the master node (111) and from the slave node (122).

Abstract: A method and apparatuses detect arc faults. The apparatus according to one embodiment comprises: a master node (111) for digitally detecting a current signal and a voltage signal at a first point in a wiring system (131); a slave node (122) for digitally detecting a current signal and a voltage signal at a second point in the wiring system (131); and a detection unit for detecting an arc fault in the wiring system (131) by comparing the current signals from the master node (111) and from the slave node (122), and comparing the voltage signals from the master node (111) and from the slave node (122).

Abstract: Redundant functionality is implemented in a control of solid state power switching controller (SSPC) (1) to ensure that each power switching channel operates according to a default configuration in case of failure. Each power switching channel in the SSPC includes a solid state switching device (SSSD) (120) that is controlled by a supervisory controller (10) to perform power switching functions for a corresponding load. The SSPC further includes a nonvolatile memory device (44) that stores default commands for controlling the SSSDs in case the SSPC enters into a backup mode, e.g., due to a failure in the supervisory controller. The nonvolatile memory device may be assembled on the same SSPC circuit board as the power switching channels, thereby ensuring that backup control is performed locally in the SSPC device.

Abstract: An electrical power distribution system is disclosed that includes a gateway module (100) including logic (112) to interface to a vehicle management computer (VMC) (50) via a dual redundant standard data bus (1). The gateway module (100) has redundant microcontrollers (114, 116) operably connected to the VMC (50) for selectively controlling supply of electrical power to a plurality of separate electrical loads (120). A plurality of Load Management Modules (300) is provided. Each Load Management Module (300) includes a local microcontroller (310); power switching devices (320); and application specific integrated circuits ASICs (330) for interfacing the power switching devices (320) to the local microcontroller (310). Each ASIC (330) can be connected to a corresponding digital potentiometer (600) that is used to program an over current protection characteristic.

Abstract: An electrical power distribution system is disclosed that includes a gateway module (100) including logic (112) to interface to a vehicle management computer (VMC) (50) via a dual redundant standard data bus (1). The gateway module (100) has redundant microcontrollers (114, 116) operably connected to the VMC (50) for selectively controlling supply of electrical power to a plurality of separate electrical loads (120). A plurality of Load Management Modules (300) is provided. Each Load Management Module (300) includes a local microcontroller (310); power switching devices (320); and application specific integrated circuits ASICs (330) for interfacing the power switching devices (320) to the local microcontroller (310). Each ASIC (330) can be connected to a corresponding digital potentiometer (600) that is used to program an over current protection characteristic.