Control systems and methods suitable for combination with power production systems and methods are provided herein. The control systems and methods may be used with, for example, closed power cycles as well as semi-closed power cycles. The combined control systems and methods and power production systems and methods can provide dynamic control of the power production systems and methods that can be carried out automatically based upon inputs received by controllers and outputs from the controllers to one or more components of the power production systems.

Systems and methods relating to use of external air for inventory control of a closed thermodynamic cycle system or energy storage system, such as a reversible Brayton cycle system, are disclosed. A method may involve, in a closed cycle system operating in a power generation mode, circulating a working fluid may through a closed cycle fluid path. The closed cycle fluid path may include a high pressure leg and a low pressure leg. The method may further involve in response to a demand for increased power generation, compressing and dehumidifying environmental air. And the method may involve injecting the compressed and dehumidified environmental air into the low pressure leg.

Systems and methods relating to use of external air for inventory control of a closed thermodynamic cycle system or energy storage system, such as a reversible Brayton cycle system, are disclosed. A method may involve, in a closed cycle system operating in a power generation mode, circulating a working fluid may through a closed cycle fluid path. The closed cycle fluid path may include a high pressure leg and a low pressure leg. The method may further involve in response to a demand for increased power generation, compressing and dehumidifying environmental air. And the method may involve injecting the compressed and dehumidified environmental air into the low pressure leg.

A gas turbine engine for an aircraft and a method of operating a gas turbine engine on an aircraft. Embodiments disclosed include a gas turbine engine for an aircraft including: an engine core has a turbine, a compressor, and a core shaft; a fan located upstream of the engine core, the fan has a plurality of fan blades; a nacelle surrounding the engine core and defining a bypass duct and bypass exhaust nozzle; and a gearbox that receives an input from the core shaft and outputs drive to the fan wherein the gas turbine engine is configured such that a jet velocity ratio of a first jet velocity exiting from the bypass exhaust nozzle to a second jet velocity exiting from an exhaust nozzle of the engine core at idle conditions is greater by a factor of 2 or more than the jet velocity ratio at maximum take-off conditions.

A gas turbine engine for an aircraft and a method of operating a gas turbine engine on an aircraft. Embodiments disclosed include a gas turbine engine for an aircraft including: an engine core has a turbine, a compressor, and a core shaft; a fan located upstream of the engine core, the fan has a plurality of fan blades; a nacelle surrounding the engine core and defining a bypass duct and bypass exhaust nozzle; and a gearbox that receives an input from the core shaft and outputs drive to the fan wherein the gas turbine engine is configured such that a jet velocity ratio of a first jet velocity exiting from the bypass exhaust nozzle to a second jet velocity exiting from an exhaust nozzle of the engine core at idle conditions is greater by a factor of 2 or more than the jet velocity ratio at maximum take-off conditions.

A micro gas turbine equipped with a valve mechanism by means of which the operation of the micro gas turbine can be influenced and optimized, particularly by regulating a supply of hot gas from the cabinet and/or the exhaust of the micro gas turbine to an inlet side of the compressor. When the temperature of ambient air is relatively low, thermal output and thermal efficiency of a micro gas turbine decrease. The present micro gas turbine compensates for the loss of thermal efficiency.

A micro gas turbine equipped with a valve mechanism by means of which the operation of the micro gas turbine can be influenced and optimized, particularly by regulating a supply of hot gas from the cabinet and/or the exhaust of the micro gas turbine to an inlet side of the compressor. When the temperature of ambient air is relatively low, thermal output and thermal efficiency of a micro gas turbine decrease. The present micro gas turbine compensates for the loss of thermal efficiency.

Systems and methods relating to variable pressure turbines are disclosed. A power generation system may include a closed cycle system configured to generate power, a combustor, and a control system. The closed cycle system may include a working fluid circulating in a closed cycle path. The combustor may provide thermal energy to the working fluid. Further, the control system may be configured to determine to increase an amount of power generated by the closed cycle system, and in response to the determination to increase the amount of power generated by the closed cycle system, cause an increase in pressure of the working fluid in the closed cycle path.

Systems and methods relating to variable pressure turbines are disclosed. A power generation system may include a closed cycle system configured to generate power, a combustor, and a control system. The closed cycle system may include a working fluid circulating in a closed cycle path. The combustor may provide thermal energy to the working fluid. Further, the control system may be configured to determine to increase an amount of power generated by the closed cycle system, and in response to the determination to increase the amount of power generated by the closed cycle system, cause an increase in pressure of the working fluid in the closed cycle path.

A switched reluctance motor is disclosed. The switched reluctance motor includes a rotor, a stator, an air gap between the stator and the rotor, and a plurality of conductive elements. The plurality of conductive elements are disposed on the rotor.