Abstract: Methods and apparatus for detecting and characterizing arc faults in an aerospace electric propulsion system and then coordinating the operation of various elements of the protection system to execute a fault-clearing sequence. In a current-based method, the arc is detected and characterized based on differential readouts from current sensors. The difference between currents measured at two ends of a protection zone are compared to a difference threshold. In a power-based method, the arc is detected and characterized based on differential readouts from voltage and current sensors. The differential voltage and current readouts are used to compute the respective powers at two ends of a protection zone. The difference between the respective powers is integrated over a period of time and then the integrated difference is compared to a difference threshold. A differential protection trip mode is invoked when the difference threshold is exceeded.

Abstract: An architecture for an aircraft comprises two air-conditioning systems, two converters, each intended to supply one of the air-conditioning systems, and at least one first electric machine which starts up a first main engine of the aircraft. The electrical architecture is configured such that the two converters can together supply the first electric machine. A method of operating the architecture is also provided.

Abstract: Systems for suppressing adverse exothermic reactions in an energy storage container. One energy storage system includes a container configured to support a plurality of battery cells; a plurality of battery cells disposed inside and supported by the container; an agent supply port attached to the container; and a tube disposed inside the container and having a closed end and an open end. The open end of the tube is in fluid communication with the agent supply port. The tube comprises fusible portions which are designed to melt or soften at a temperature which is lower than the melting or softening temperature of another portion of the tube. In response to melting or softening of the fusible portions of the tube, pressurized exothermic reaction-suppressing agent is distributed inside the container via the tube.

Abstract: Methods and systems for charging a battery string while protecting against overcharging. One system includes: a pair of disconnect devices; a power distribution bus which is electrically connected to a battery string via the disconnect devices; a battery charger connected to supply battery power to the power distribution bus for charging the battery string; a module monitoring unit configured to sense individual battery cell voltages during charging; a first processor configured to activate one disconnect device to open when the sensed individual battery cell voltages indicate overcharging; a plurality of sensors connected to sense a full-string voltage measured across the battery string and first and second half-string voltages measured across first and second half-strings of the battery string; and a second processor connected to receive sensor data during charging.

Abstract: An electric propulsion unit comprising a housing, an AC motor, a beta rod, a propeller, a governor, an inverter, and a controller. The AC motor is disposed within the housing and includes a plurality of bearings supported inside the housing, a hollow motor shaft rotatably coupled to the housing by the plurality of bearings, a stator which is supported by the housing, and a rotor which is mounted to the hollow motor shaft. The beta rod is axially translatable inside the hollow motor shaft. The propeller is mechanically coupled to the hollow motor shaft. The propeller includes propeller blades having an adjustable pitch angle which depends on an axial position of the beta rod. The governor is configured to adjust a pitch angle of the propeller blades by actuating axial translation of the beta rod. The inverter is disposed within the housing and connected to receive DC power for conversion into AC power.

Abstract: Methods and systems for protection/disconnect of airborne high-power/energy high-voltage modular multi-string battery packs (such as battery packs for airborne electric propulsion systems). The methods and systems are based on a dissimilar/redundant distributed battery pack protection architecture and use a smart mid-point battery disconnect in conjunction with centralized battery management system. The resulting battery disconnect/protection system is configured to detect bus faults, load faults and string faults and then take appropriate action to isolate the detected fault. For example, in response to a short circuit in one battery string, the faulty battery string may be disconnected from the positive and negative busbars while the remaining battery strings continue to provide power.

Abstract: A method for protecting an electric propulsion system in response to occurrence of a fault. The method includes the step of activating short circuits in power switches of inverters in a motor controller to redirect current regenerated by a motor which is electrically coupled to the motor controller and mechanically coupled to a propeller. The method further includes feathering the propeller while the motor is regenerating current. The protection logic is designed to address different types of faults, including faults in the high-voltage direct-current bus, faults in the motor controller, and faults in the motor.

Abstract: Systems and methods for current ripple reduction for a direct current (DC) source powering an alternating current (AC) load. In accordance with one embodiment, the system and method involve interleaved operation of a 3×3-phase AC motor having multiple groups of windings. In accordance with another embodiment, the system and method involve interleaved operation of multiple co-shafted 3-phase AC motors. In accordance with a further embodiment, the system and method involve interleaved operation multiple 3-phase AC motors (not co-shafted) of the same level of power. The interleaved operation entails interleaved switching inside a set of inverters which are connected in parallel between a DC bus and the windings of the AC motor (motors).

Abstract: A fault-tolerant power system architecture for aircraft electric propulsion. The fault-tolerant systems continue to operate in the event of the failure of (or one or more faults within) some component. The fault-tolerant design enables the system to continue its intended operation, possibly at a reduced level, rather than failing completely, when some part of the system fails. When a turn-to-turn fault in an AC motor is detected, a motor controller will short three top or three bottom switches in the inverter together (effectively shorting the associated stator windings) to divert fault current from the motor windings to the motor controller, where cooling is available. Also, when a fault in or at the input to a motor controller is detected, the motor controller cuts off power to the motor by issuing a command that causes an upstream contactor with high-voltage DC bus input to open.

Abstract: Systems and methods for current ripple reduction for a direct current (DC) source powering an alternating current (AC) load. In accordance with one embodiment, the system and method involve interleaved operation of a 3×3-phase AC motor having multiple groups of windings. In accordance with another embodiment, the system and method involve interleaved operation of multiple co-shafted 3-phase AC motors. In accordance with a further embodiment, the system and method involve interleaved operation multiple 3-phase AC motors (not co-shafted) of the same level of power. The interleaved operation entails interleaved switching inside a set of inverters which are connected in parallel between a DC bus and the windings of the AC motor (motors).

Abstract: An electrical transformer includes a first winding, called primary, at least one second winding, called secondary, switches, and a current detection system, wherein it comprises at least one metal screen having a connection point linked to a neutral potential of the primary winding or intended to be linked to an electrical ground and placed between the primary winding and the at least one secondary winding, the screen being made of an electrically conductive material having a melting point higher than that of the materials constituting the windings; in that the primary winding comprises an input intended to be linked to an external energy source, the switches are placed at the input of the primary winding so as to be able to isolate the primary winding from the external energy source and in that the current detection system is configured to detect a current at the input of the primary winding or a current at the connection point and to close or open the switches based on the detection of the current, the dete

Abstract: An inductive filtering device includes a plurality of grouped electrical conductors and at least two toric magnetic cores, each formed around a central void, the two magnetic cores having different magnetic lengths, the electrical conductor being wound together around both magnetic cores by passing through the central voids of both magnetic cores.

Abstract: An electrical architecture for controlling inverters and to an aircraft includes the architecture. The electrical architecture comprises: a plurality of converters capable of operating independently of one another, each converter being intended to power a charge, associated with each converter/charge pair: a charging loop, comprising at least one sensor measuring a parameter that is characteristic of the operation of the charge, an operation control module, receiving an operation setpoint of the charge and information originating from the operation sensor, the operation control module controlling a current setpoint of the considered converter so that the information originating from the operation sensor follows the operation setpoint. The operation control module is common to the converters.

Abstract: A voltage step-up autotransformer topology and an AC-to-DC converter including such an autotransformer are provided. The autotransformer is configured to take, at input, a three-phase AC current (for example 115 VAC with a constant frequency), and to output nine output voltages, which are supplied to an 18-pulse rectifier bridge assembly so as to supply a high DC voltage (for example +270 VDC/?270 VDC). These are particularly suitable for AC-to-DC converters in the aeronautical sector.

Abstract: An electrical transformer includes a first winding, called primary, at least one second winding, called secondary, switches, and a current detection system, wherein it comprises at least one metal screen having a connection point linked to a neutral potential of the primary winding or intended to be linked to an electrical ground and placed between the primary winding and the at least one secondary winding, the screen being made of an electrically conductive material having a melting point higher than that of the materials constituting the windings; in that the primary winding comprises an input intended to be linked to an external energy source, the switches are placed at the input of the primary winding so as to be able to isolate the primary winding from the external energy source and in that the current detection system is configured to detect a current at the input of the primary winding or a current at the connection point and to close or open the switches based on the detection of the current, the dete

Abstract: An architecture for an aircraft comprises two air-conditioning systems, two converters, each intended to supply one of the air-conditioning systems, and at least one first electric machine which starts up a first main engine of the aircraft. The electrical architecture is configured such that the two converters can together supply the first electric machine. A method of operating the architecture is also provided.

Abstract: An electrical architecture for controlling inverters and to an aircraft includes the architecture. The electrical architecture comprises: a plurality of converters capable of operating independently of one another, each converter being intended to power a charge, associated with each converter/charge pair: a charging loop, comprising at least one sensor measuring a parameter that is characteristic of the operation of the charge, an operation control module, receiving an operation setpoint of the charge and information originating from the operation sensor, the operation control module controlling a current setpoint of the considered converter so that the information originating from the operation sensor follows the operation setpoint. The operation control module is common to the converters.

Abstract: A voltage step-up autotransformer topology and an AC-to-DC converter including such an autotransformer are provided. The autotransformer is configured to take, at input, a three-phase AC current (for example 115 VAC with a constant frequency), and to output nine output voltages, which are supplied to an 18-pulse rectifier bridge assembly so as to supply a high DC voltage (for example +270 VDC/?270 VDC). These are particularly suitable for AC-to-DC converters in the aeronautical sector.

Abstract: A battery module system includes at least one cell and a battery module processor. The battery module processor may be configured to receive at least one cell signal associated with the at least one cell, wherein the at least one cell signal includes at least one of a temperature signal, a voltage signal, or a current signal. The battery module processor may be also configured to determine a status of the at least one cell based on the at least one cell signal. The battery module system may be configured to removably connect to a master/module interface, and to deliver power from the at least one cell to the master/module interface. The battery module system may be also configured to communicate, from the battery module processor, the status of the at least one cell to the master/module interface.

Abstract: An electrical network of an aircraft comprises: several main generators, several high voltage direct current networks powered by one of the generators in normal operation, several low voltage direct current networks powered by one of the high voltage direct current networks, several converters to transfer energy from one of the high voltage direct current networks to one of the low voltage direct current networks, the different converters being independent and isolated from each other, each converter being dedicated to one of the high voltage networks and to the low voltage direct current network, a load designed to be powered in normal operation by the main generators and in backup operation by one of the low voltage direct current networks, the backup operation being put into place when at least one of the high voltage networks is no longer powered by the associated main generator in normal operation.