A control device includes: a variation command unit that changes a command value, which is a command value sent to a system including a compressor, affecting an operating state of the compressor; a proportional coefficient calculation unit that calculates a proportional coefficient of a variation in a parameter, which indicates a state of the compressor or an electric motor that drives the compressor when the system is operated based on the command value, with respect to the command value; and a control unit that performs control for avoiding or suppressing surging in the compressor, based on a value of the proportional coefficient.

Provided is a compressor control device configured to control a flow rate of a compressor having a plurality of impellers connected to an outlet port-side flow path in parallel and a flow rate regulation unit configured to regulate a flow rate of each of the impellers, the compressor control device including a pressure detection unit configured to detect a pressure of the outlet port-side flow path, a flow rate detection unit configured to detect the flow rate of each of the impellers, and a control unit configured to output a flow rate regulation command of each of the impellers to the flow rate regulation unit and control the flow rate regulation unit based on the detection result of the pressure detection unit.

A surge control system includes a rotor system with at least one compressor section and at least one turbine section operably coupled to a shaft. The surge control system also includes sensors configured to collect sensor data from the rotor system, an electric motor operably coupled to the rotor system, and a controller. The controller is operable to detect surge event from the sensor data, determine an amount of power to apply to the rotor system, and increase the amount of power provided to the rotor system to recover from the surge event.

Centrifugal compressors can incorporate a side stream flow of intermediate pressure vapor between stages of that compressor. The side stream flow can be controlled by a side stream injection port controlled by a capacity control valve that has a curved surface facing a flow of refrigerant from the first stage to the second stage. The capacity control valve can allow or obstruct flow through the side stream injection port. The capacity control valve can extend and retract in a direction substantially perpendicular to the direction of flow from the first stage impeller to the second stage impeller. The side stream injection port and the capacity control valve can be ring-shaped. The side stream injection port and the capacity control valve can allow at least some of the side stream to be introduced on a side of the capacity control valve opposite the curved surface.

A compressor system (10) includes a motor (3) including a rotor (31) configured to rotate about an axis and a stator (32) disposed on an outer circumference side of the rotor (31), a compressor (2) including an impeller (22) configured to compress a working fluid (31) by rotating together with the rotor and a housing (23) covering the impeller (22) from an outer circumference side, and a heat exchange flow path (600) through which a fluid flowing inside the stator (32) or in a gap between the stator (32) and the rotor (31) is flowed and heat is exchangeable between the fluid and the housing (23).

An improved compressed air system utilizes one or more base compressors, such as fixed speed drive compressors, to meet the compressed air demands and one or more trim compressors, such as variable speed drive compressors, to meet the variations in the demand. The operation of both the base and trim compressors may be controlled to provide improved overall efficiency while meeting the transient load demands. The control may spread the demands over the various base compressors to improve the overall loading on each base compressor. Efficiency metrics may be utilized to control the switching between base and trim compressors. Unloading of a base compressor may be controlled to avoid undesirable changes in system performance.

A product and method are disclosed for use with an engine including an intake passage providing combustion air to the engine. An exhaust passage may channel expelled combustion gases from the engine. A first compressor may be disposed in the intake passage, and a turbine may be disposed in the exhaust passage and may be coupled to the first compressor. The turbine may be arranged to rotate as a result of a flow of exhaust gases through the exhaust passage to drive the first compressor. A flow control device may be disposed in the intake passage upstream from the first compressor. An alternate passage may be provided having a first end opening to the intake passage upstream from the flow control device and having a second end opening to the intake passage downstream from the flow control device. A second compressor may be disposed in the alternate passage, with a drive unit adapted to drive the second compressor. The flow control device may be adapted to be closed to substantially prevent flow through the intake passage and to be open to impart swirl to a gas stream in the intake passage.

A method for controlling at least one radial blower in a cooling system, wherein the radial blower comprises a housing in which a shaft is rotationally mounted, which receives at least one impeller wheel of a compressor at one end, which is secured to the housing, and the housing comprises at least one radial bearing and at least one axial bearing via which the shaft is rotationally mounted in the housing, and said radial blower also comprises a motor which is driven by a rotor and a stator and which drives the shaft, wherein, by means of at least one laser Doppler vibrometer assigned to the shaft, operating points of the shaft are detected and forwarded to a controller for determining an operating status of the radial blower.

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 variable speed compressor includes a housing assembly having a suction port and an inlet port, a motor disposed within the housing assembly, and at least one rotatable element mounted within the housing assembly. The at least one rotatable element is driven by the motor about an axis of rotation. The variable speed compression additionally includes an unloading system having at least one valve. The unloading system is selectively operable to supplement an unloading of the variable speed compressor defined by an operational speed of the variable speed compressor.