Abstract: Energy storage systems for aircraft and methods of operating the same are provided. The energy storage system may include a main battery, a propulsion power bus, a non-critical bus, a critical bus, and an engine starter bus. The propulsion power bus may be configured to convey electricity, which is supplied by the main battery, to an electric propulsion machine configured to provide propulsion for the aircraft. The non-critical bus may be configured to convey electricity to a hotel load on the aircraft. The critical bus may be configured to convey electricity, which is supplied by the main battery, to a critical load on the aircraft. The engine starter bus may be configured to convey electricity, which is supplied by the main battery, to an electric starter for a gas turbine engine, where the gas turbine engine is configured to power the electric propulsion machine.

Abstract: Electrical voltage detection circuit and methods for determining the presence or absence of voltage in electrical equipment. An isolated power supply provides power to one or more voltage detection devices configured to detect voltage on one or more busses of electrical equipment. A switch is configured to provide supply voltage from the isolated power supply to the one or more busses of electrical equipment when the switch is closed. The voltage detection devices may determine if the one or more busses of electrical equipment are de-energized by detecting the voltage on the busses when the switch is open. The integrity of the electrical equipment may be verified by detecting, with the voltage detection devices, the voltage on the busses when the switch is closed, where the expected voltage readings are based on voltages being provided to one or more busses by the isolated power supply.

Abstract: Energy storage systems for aircraft and methods of operating the same are provided. The energy storage system may include a main battery, a propulsion power bus, a non-critical bus, a critical bus, and an engine starter bus. The propulsion power bus may be configured to convey electricity, which is supplied by the main battery, to an electric propulsion machine configured to provide propulsion for the aircraft. The non-critical bus may be configured to convey electricity to a hotel load on the aircraft. The critical bus may be configured to convey electricity, which is supplied by the main battery, to a critical load on the aircraft. The engine starter bus may be configured to convey electricity, which is supplied by the main battery, to an electric starter for a gas turbine engine, where the gas turbine engine is configured to power the electric propulsion machine.

Abstract: Electrical voltage detection circuit and methods for determining the presence or absence of voltage in electrical equipment. An isolated power supply provides power to one or more voltage detection devices configured to detect voltage on one or more busses of electrical equipment. A switch is configured to provide supply voltage from the isolated power supply to the one or more busses of electrical equipment when the switch is closed. The voltage detection devices may determine if the one or more busses of electrical equipment are de-energized by detecting the voltage on the busses when the switch is open. The integrity of the electrical equipment may be verified by detecting, with the voltage detection devices, the voltage on the busses when the switch is closed, where the expected voltage readings are based on voltages being provided to one or more busses by the isolated power supply.

Abstract: A system includes a DC to DC converter coupled with a load, a power source bus coupled with an input of the DC to DC converter, a capacitor coupled in parallel across an output of the DC to DC converter and a controller. The controller may dynamically adjust a bus voltage set point of a bus voltage on the output of the DC to DC converter up or down to prepare for supply of the bus voltage and energy stored in the capacitor to an anticipated load event. The load event may have a load step change that occurs in less than five milliseconds and is greater than about eighty or eighty-five percent of a rated output of the DC to DC converter.

Abstract: A battery arrangement for a gas turbine engine, the battery arrangement comprising: a wall of the gas turbine engine; a thermal battery coupled to the wall and arranged to receive thermal energy from gas of the gas turbine engine; and charging circuitry configured to supply electrical energy to the thermal battery to recharge the thermal battery.

Abstract: A system includes a DC to DC converter coupled with a load, a power source bus coupled with an input of the DC to DC converter, a capacitor coupled in parallel across an output of the DC to DC converter and a controller. The controller may dynamically adjust a bus voltage set point of a bus voltage on the output of the DC to DC converter up or down to prepare for supply of the bus voltage and energy stored in the capacitor to an anticipated load event. The load event may have a load step change that occurs in less than five milliseconds and is greater than about eighty or eighty-five percent of a rated output of the DC to DC converter.

Abstract: Controllable cleavage of a work piece is achieved through the use of capacitive clamps and application of a large tensile force. Capacitive clamps are used to secure the ends of a work piece with strong electrostatic forces. The capacitive clamps secure the ends of the work piece by creating electrostatic forces like those experienced by the plates in a parallel plate capacitor. After introduction of a crack along a side surface of the work piece, the application of a tensile force along the central axis of the work piece causes the crack to rapidly propagate and cleave the work piece into two or more pieces.

Abstract: A battery arrangement for a gas turbine engine, the battery arrangement comprising: a wall of the gas turbine engine; a thermal battery coupled to the wall and arranged to receive thermal energy from gas of the gas turbine engine; and charging circuitry configured to supply electrical energy to the thermal battery to recharge the thermal battery.

Abstract: Controllable cleavage of a work piece is achieved through the use of capacitive clamps and application of a large tensile force. Capacitive clamps are used to secure the ends of a work piece with strong electrostatic forces. The capacitive clamps secure the ends of the work piece by creating electrostatic forces like those experienced by the plates in a parallel plate capacitor. After introduction of a crack along a side surface of the work piece, the application of a tensile force along the central axis of the work piece causes the crack to rapidly propagate and cleave the work piece into two or more pieces.

Abstract: A recombinator for a flow battery including at least one input configured to provide a halogen containing flow stream and hydrogen gas to a reaction chamber and a substrate located in the reaction chamber. The substrate is configured to be directly heated and the substrate contains a catalyst. The recombinator is configured to react the hydrogen gas and the halogen using the catalyst to form a hydrogen-halogen compound.