A blower in one aspect of the present disclosure includes: a housing including a first discharge port; a motor in the housing; a fan in the housing; an attachment fitting portion; and a motor drive circuit. The attachment fitting portion is configured to detachably attach, to the first discharge port, an attachment including a second discharge port. The motor drive circuit (i) delivers a designated power to the motor and (ii) performs a constant power control that maintains a magnitude of an electric power delivered to the motor at a magnitude of the designated power.

A method for managing power drawn from power units of propulsion units of an aircraft, wherein the method includes a step of increasing the amount of power drawn from a second power unit that is time shifted, with respect to a step of increasing the amount of power drawn from a first power unit, for a duration that at least allows the operational state or the non-operational state of the first power unit to be determined. This solution allows simultaneous switching to the non-operational state of the two power units to be avoided.

A method and controller for operating a pumping station. The method includes receiving (1102), by at least one controller (910, 952), sensor data (712) of a first pumping station (900) corresponding to a liquid being transported from the first pumping station (900). The method includes predicting (1104) arrival of the liquid, by the at least one controller (910, 952), at a second pumping station (900). The method includes executing (1106) one or more pump models (720), by the at least one controller (910, 952), according to the sensor data (712) to determine an optimal pumping configuration. The method includes operating (1108) one more pumps of the second pumping station (900), by the at least one controller (910, 952), according to the optimal pumping configuration.

The present disclosure relates to systems and methods that are useful in control of one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants, methods of starting power production plants, and methods of generating power with a power production plant wherein one or more control paths are utilized for automated control of at least one action. The present disclosure more particularly relates to power production plants, control systems for power production plants, and methods for startup of a power production plant.

A method for controlling a turbomachine comprising an electric motor forming a torque injection device on a high-pressure rotation shaft, in which method a fuel flow setpoint Q.sub.CMD and a torque setpoint TRQ.sub.CMD provided at the electric motor are determined, the control method comprising: • a step of implementing a first fuel control loop in order to determine the fuel flow set point QCMD, • a step of implementing a second, torque control loop in order to determine the torque setpoint TRQ.sub.CMD comprising i. a step of determining a torque correction variable ΔTRQ.sub.CMD as a function of a transitory speed setpoint NHTrajAccelCons, NHTrajDecelCons and ii. a step of determining the torque setpoint TRQ.sub.CMD as a function of the torque correction variable ΔTRQ.sub.CMD.

A vacuum pump and a controller are provided with which state information of the vacuum pump is collected in a timely manner. In a controller, control portions control operating states of internal devices (such as a motor, a heater, and a cooling valve) located in a vacuum pump main body. An information collection portion collects the state information of the vacuum pump main body, and a recording processing portion records, in the non-volatile memory, the state information collected by the information collection portion. Also, the information collection portion collects the state information of the vacuum pump main body at a point in time at which a control portion switches the operating state of an internal device.

The method can include determining a mass flow rate W of working fluid circulating through the compressor stage, determining a control parameter value associated to the geometrical configuration of the variable geometry element based on the determined value of mass flow rate W; and changing the geometrical configuration of the variable geometry element in accordance with the determined control parameter value.

A gas turbine engine includes an electrical machine positioned at least partially inward of a core airflow path, the electrical machine including an electrical rotor component and an electrical stator component, a connecting member positioned between the electrical machine and a rotary member, a disconnection device that is positionable between a disengaged position, in which the disconnection device is disengaged from the connecting member, and an engaged position, in which the disconnection device is engaged with the connecting member, and a controller including a processor, where the processor receives a signal from the electrical machine indicative of a fault, and in response to receiving the signal from the electrical machine indicative of the fault, directs the disconnection device to move from the disengaged position to the engaged position.

An aircraft including lean-burn gas turbine engines operating in pilot-plus-mains mode with a given initial fuel flow W.sub.0, a method of controlling the optical depth of contrails produced by a first group of engines includes the steps of (i) reducing fuel flow to each engine in the first group to change the operation of each engine from pilot-plus-mains mode to pilot-only mode, and (ii) adjusting fuel flow to one or more engines in a second group of engines such that the total fuel flow to engines of the second group is increased, all engines of the second group remaining in pilot-plus-mains mode, and wherein the set of lean-burn engines consists of the first and second groups. Depending on atmospheric conditions, the average optical depth of contrails produced by the engines may be enhanced or reduced compared to when all engines operate in pilot-plus-mains mode with a fuel flow W.sub.0.

A fan assembly is provided. The fan assembly includes a fan, a motor that is coupled to the fan, and a variable frequency drive (VFD) that is coupled to the motor. The motor includes a maximum rated speed that is greater than a maximum structural speed limit of the fan, and the VFD includes a current output limit configured to limit an operational speed of the motor to be less than or equal to the maximum structural speed limit of the fan.