Abstract: A turbine-compressor assembly includes a turbine-compressor device fluidly coupled with a heat source, a compressor, and a turbine via plural valves. A power device is coupled with the turbine-compressor device via a shaft. A controller can control operation of the plural valves to control the movement of fluids within the assembly to selectively switch between the turbine-compressor device operating in one of plural operating modes. In a first mode of operation, the turbine-compressor device can generate electrical power and direct the electrical power to the power device to control an amount of power provided to or extracted from the shaft by the power device. In a second mode of operation, the turbine-compressor device can receive electrical power from the power device to consumer the electrical power.

Abstract: A method and a turbine-compressor assembly of a system having a turbine-compressor device fluidly coupled with a heat source, a compressor, and a turbine via plural valves. A power device may be coupled with the turbine-compressor device. A controller may control operation of the plural valves to control movement of fluids within the assembly to selectively switch between the turbine-compressor device operating in one of plural modes. In a turbine mode of operation, the turbine-compressor device may generate electrical power and direct the electrical power to the power device. In a compressor mode of operation, the turbine-compressor device may receive electrical power from the power device to consume the electrical power.

Abstract: A method and a turbine-compressor assembly of a system having a turbine-compressor device fluidly coupled with a heat source, a compressor, and a turbine via plural valves. A power device may be coupled with the turbine-compressor device. A controller may control operation of the plural valves to control movement of fluids within the assembly to selectively switch between the turbine-compressor device operating in one of plural modes. In a turbine mode of operation, the turbine-compressor device may generate electrical power and direct the electrical power to the power device. In a compressor mode of operation, the turbine-compressor device may receive electrical power from the power device to consume the electrical power.

Abstract: A method and a turbine-compressor assembly of a system having an engine includes an upstream valve coupled with a compressor and a turbine-compressor device, a downstream valve coupled with a turbine and the device, and a controller to control the upstream, downstream, and a control valve. The controller selectively operates the device in a plurality of operating modes. In a turbine mode of operation, the upstream valve directs inlet air to the compressor, the turbine receives engine exhaust, the downstream valve directs first turbine exhaust from the turbine to the device, and the control valve directs second turbine exhaust from the device to an outlet. In a compressor mode of operation, the control valve directs the inlet air to the device, the upstream valve directs first compressed air from the device to the compressor, and the downstream valve directs the first turbine exhaust from the turbine to the outlet.

Abstract: A method and a turbine-compressor assembly of a system having an engine includes an upstream valve coupled with a compressor and a turbine-compressor device, a downstream valve coupled with a turbine and the device, and a controller to control the upstream, downstream, and a control valve. The controller selectively operates the device in a plurality of operating modes. In a turbine mode of operation, the upstream valve directs inlet air to the compressor, the turbine receives engine exhaust, the downstream valve directs first turbine exhaust from the turbine to the device, and the control valve directs second turbine exhaust from the device to an outlet. In a compressor mode of operation, the control valve directs the inlet air to the device, the upstream valve directs first compressed air from the device to the compressor, and the downstream valve directs the first turbine exhaust from the turbine to the outlet.

Abstract: A method and a turbine-compressor assembly of a system having an engine includes an upstream valve coupled with a compressor and a turbine-compressor device, a downstream valve coupled with a turbine and the device, and a controller to control the upstream, downstream, and a control valve. The controller selectively operates the device in a plurality of operating modes. In a turbine mode of operation, the upstream valve directs inlet air to the compressor, the turbine receives engine exhaust, the downstream valve directs first turbine exhaust from the turbine to the device, and the control valve directs second turbine exhaust from the device to an outlet. In a compressor mode of operation, the control valve directs the inlet air to the device, the upstream valve directs first compressed air from the device to the compressor, and the downstream valve directs the first turbine exhaust from the turbine to the outlet.

Abstract: A method and a turbine-compressor assembly of a system having an engine includes an upstream valve coupled with a compressor and a turbine-compressor device, a downstream valve coupled with a turbine and the device, and a controller to control the upstream, downstream, and a control valve. The controller selectively operates the device in a plurality of operating modes. In a turbine mode of operation, the upstream valve directs inlet air to the compressor, the turbine receives engine exhaust, the downstream valve directs first turbine exhaust from the turbine to the device, and the control valve directs second turbine exhaust from the device to an outlet. In a compressor mode of operation, the control valve directs the inlet air to the device, the upstream valve directs first compressed air from the device to the compressor, and the downstream valve directs the first turbine exhaust from the turbine to the outlet.

Abstract: A system includes an impedance gas sensor configured to be in contact with one or more hydrocarbons. The impedance sensor includes electrodes and a sensing region circuit that is configured to have a sensing material and to generate electrical stimuli to the sensing material upon exposure to one or more hydrocarbons at one or more of a reduced heater voltage or a reduced sensing region temperature as compared to a prescribed heater voltage or a prescribed sensing region temperature. The system also includes one or more processors configured to receive electrical signals from the sensor, where the electrical signals are representative of impedance responses of the sensing material to one or more hydrocarbons. The one or more processors also are configured to analyze the impedance responses and determine an amount of at least one hydrocarbon of interest in the one or more hydrocarbons.

Abstract: A system includes an impedance gas sensor configured to be in contact with one or more hydrocarbons. The impedance sensor includes electrodes and a sensing region circuit that is configured to have a sensing material and to generate electrical stimuli to the sensing material upon exposure to one or more hydrocarbons at one or more of a reduced heater voltage or a reduced sensing region temperature as compared to a prescribed heater voltage or a prescribed sensing region temperature. The system also includes one or more processors configured to receive electrical signals from the sensor, where the electrical signals are representative of impedance responses of the sensing material to one or more hydrocarbons. The one or more processors also are configured to analyze the impedance responses and determine an amount of at least one hydrocarbon of interest in the one or more hydrocarbons.