A method of operating a gas turbine engine compressor. The method includes: determining an operating point of the compressor, and modulating mass flow of environmental control system input air to maintain the operating point of the gas turbine engine compressor within predetermined limits.

A turbo blower operable in a surge area and, more particularly, a turbo blower operable in a surge area is provided. The turbo blower increases consistency of performance thereof and efficiency by preventing suspension thereof due to a temporarily generated surge by operating even in a surge area for a predetermined time in addition to a normal area in which the turbo blower normally operates.

A compressor including a gear system configured to be driven by a drive unit, a plurality of compression stages coupled to the gear system, wherein the plurality of compression stages includes at least one centrifugal compression stage and at least one positive displacement compression stage, is provided. Furthermore, an associated method is also provided.

The invention enables quick evacuation of a chamber to a specified target degree of vacuum while increasing selectivity of evacuation conditions. A vacuum-processing device contains a chamber 40 that enables a workpiece to be soldered in a vacuum environment, an operating part 20 that sets a condition for evacuating the chamber 40, a pump 23 that evacuates the chamber 40, and a control portion 61 that calculates the amount of decrease in the degree of vacuum when evacuating the chamber 40 using a predetermined pump output, sets the calculated value as a reference value and switches an evacuation property from the evacuation property including a lower pump output to the evacuation property including a higher pump output when the calculated amount of decrease in degree of vacuum in real time has become smaller than the reference value.

A condition monitoring device for an extracted-gas compression system including a compressor which increases pressure of extracted gas includes: a sensor for detecting a state quantity of the extracted gas flowing into the compressor; an erosion progression level calculation unit for calculating an erosion progression level of the compressor on the basis of the state quantity of the extracted gas; and a service life evaluation unit for evaluating a service life of the compressor on the basis of the erosion progression level of the compressor.

Methods and systems for controlling a chiller system to achieve control stability while maintaining optimum efficiency. Particularly, methods and systems for controlling a centrifugal compressor speed and an inlet guide vane position that establishes three distinct regions in the control path: (i) during initial unloading from full load, the inlet guide vane position is kept at a fully open position while the centrifugal compressor speed is changed to achieve the desired cooling capacity; (ii) between an inflection point and a transition point, keeping the centrifugal compressor speed constant while the inlet guide vane position is changed to achieve the desired cooling capacity; and (iii) between the transition point and zero cooling capacity, changing both the inlet guide vane position and the centrifugal compressor speed to achieve the desired cooling capacity.

A method is provided for operating a fluid conveying device of a motor vehicle having at least one aerodynamic bearing. The method reduces the rotational speed of the aerodynamic bearing to a rest speed, wherein the rest speed is below a lifting speed, in which case the bearing builds up an air film for bearing free of mixed friction, and wherein the rest speed is above a lowering speed, in which case the bearing has reduced the air film such that mixed friction occurs. The fluid conveying device is operated at the rest speed.

twin-flow, double body turbojet includes a fan that is positioned upstream from a gas generator and delimits primary and secondary flows. The gas generator is traversed by the primary flow and includes a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine and a low-pressure turbine. The low-pressure turbine is linked to the low-pressure compressor by a low-pressure rotating shaft, and the high-pressure turbine is linked to the high-pressure compressor by a high-pressure rotating shaft. The turbojet has an electric motor for injecting mechanical power into at least one of the rotating shafts. The turbojet also has a device for removing power from at least one of the rotating shafts and transforming the excess power into electrical energy. An electric storage means is positioned between the device for removing power and the electric motor.

A system includes a dynamic compressor, a variable frequency drive (VFD), and a controller. The dynamic compressor includes a motor having a driveshaft rotatably supported within the dynamic compressor, and a compression mechanism connected to the driveshaft and operable to compress a working fluid upon rotation of the driveshaft. The VFD includes a sensor configured to sense a current provided to the motor. The controller is connected to the motor and includes a processor and a memory. The memory stores instructions that program the processor to operate the motor using the VFD to compress the working fluid, receive signals representing the current from the VFD to the motor, and determine when a surge event has occurred based at least in part on the received signals representing the current from the VFD to the motor.

A vacuum pump device comprises: a power supply device including a dew condensation detector configured to detect dew condensation, a regenerative braking resistance, and a controller configured to energize the regenerative braking resistance; a cooling system using coolant; and a pump main body including a motor rotatably driven by the power supply device. When the dew condensation detector detects the dew condensation, the controller energizes the regenerative braking resistance to heat an inside of the power supply device.