39 results about "Compressor map" patented technology

In a method of operating a compressor of a gas turbine, where compressor air sucked in from the environment is cooled down by evaporation cooling before entering the compressor, before starting operation of the compressor, maximum possible temperature drops which could be achieved by evaporation cooling are determined dependent on different ambient conditions and / or are provided as a data set. These temperature drops are correlated with a compressor map containing maximum temperature distortions at different ambient conditions and different rotation frequencies of the compressor which have to be met in order to avoid pumping. The evaporation cooling is then only operated when current ambient condition result in a maximum possible temperature drop from which a predetermined fraction of between 50% and 100% does not exceed the maximum distortion which can be taken from the compressor map for these ambient conditions and the current rotation frequency of the compressor. Safe operation of the compressor can be achieved without the need or monitoring temperature distortions in the sucked in air stream.

A method and device for predictively controlling the speed of a compressor used in conjunction with a fuel cell stack. Feedforward command signals are generated based on fuel cell stack setpoints that are based on stack humidification requirements. A pressure drop model uses these setpoints to determine a compressor outlet pressure setpoint change brought about by an operational transient. A recursive approach is used to solve for one or more future or desired compressor operating conditions. The results of this recursive approach are used to determine the feedforward speed command of the compressor, where known operational parameters (such as can be found on a compressor map) may be used. This permits rapid changes in compressor speed to comply with the new operating point of the fuel cell system that is brought about by the operational transient.

A centrifugal compressor is modified by forming a bypass between the leading edge of the compressor diffuser and a point downstream from the throat of the diffuser. The bypass may be unidirectional or bi-directional. In a bi-directional embodiment, an operable flow range of the compressor can be widened in both directions of a compressor map, i.e., extending both the surge and choke margins of a compressor at the expense of normal operating efficiencies. In a unidirectional bypass embodiment the flow range may be increased only in one direction, but there is no diminishment of efficiency of the compressor at normal operating conditions. The modification provides a simple expedient for increasing flow range without a need to redesign a compressor.

A fuel cell system that employs surge prevention by electronically mapping the compressor for discharge pressure versus mass airflow. In one embodiment, the fuel cell system employs a mass flow meter that measures the airflow to the compressor. A controller receives a signal from the mass flow meter indicative of the flow rate of the charge airflow to the compressor, and determines the outlet pressure and temperature of the compressor from the compressor speed and the measured airflow. This gives the compressor map location at which the compressor is operating. In another embodiment, the fuel cell system employs a pressure sensor that measures the output pressure of the compressor, and provides a pressure signal to the controller. The controller determines the mass airflow to the compressor to determine the compressor map location.

The invention relates to a method and control system to control the speed of a centrifugal compressor operating within a vacuum pressure swing adsorption process to avoid an operation at which surge can occur and directly driven by an electric motor that is in turn controlled by a variable frequency drive. The claimed method determines the optimal speed for operation of the compressor along a peak efficiency operating line of a compressor map thereof. Speed of the compressor is adjusted by a feed back speed multiplier when the flow or other parameter referable to flow through the compressor is below a minimum and a feed forward multiplier during evacuation and evacuation with purge steps that multiplies the feed back multiplier to increase speed of the compressor and thereby avoid surge.

A fuel cell system having an adaptable compressor map and method for optimizing the adaptable compressor map is provided. The method includes the steps of establishing an initial operating setpoint for an air compressor based on the adaptable compressor map; monitoring a surge indicator; adjusting the adaptable compressor map based on the monitored surge indicator; determining a desired operating setpoint based on the adjusted adaptable compressor map; and establishing an adapted operating setpoint for the air compressor based on the adaptable compressor map following the adjustment thereof. The steps are repeated until the adaptable compressor map for the air compressor is optimized.

The proposed mechanical method of turbocompressor surge detection uses vibration signals from vibration monitoring equipment mounted on the compressor components to detect a surge event and provide antisurge control thereby. This method utilizes only mechanical information to identify surge, as compared to present day antisurge controllers that use compressor thermodynamic information such as flow, pressure, and temperature to locate a compressor's operating point on a compressor map compared to a surge region.

A control device for a supercharging system for supplying compressed intake air to an engine, is equipped with: a supercharger containing a compressor that compresses the intake air supplied to the engine; and a controller that controls control devices affecting the operation of the compressor. The controller includes: a compressor map storage unit storing a compressor map indicating the relationship between the intake air volumetric flow rate and the pressure ratio in the compressor and the compressor rotational frequency; a current position calculation unit that calculates, for each prescribed period, the current position of the operation point of the compressor in the compressor map; a movement direction calculation unit that calculates the direction of movement of the operation point in the compressor map, on the basis of the current position of the operation point as calculated by the current position calculation unit; and a control unit that controls the control devices on the basis of the current position of the operation point as calculated by the current position calculation unit, and the movement direction of the operation point as calculated by the movement direction calculation unit.

A method of surge protection for a dynamic compressor that has a corresponding compressor map. A control system continually calculates an equivalent polytropic head parameter in order to define a surge limit line. The system then calculates a control parameter and determines the distance the control parameter to the surge limit line wherein the control parameter is dynamic to changes in compressor load and invariant to changes in suction conditions and gas compressibility. As a result of the distance of the control parameter to the surge limit line, the surge valve of a dynamic compressor is actuated to prevent surge.

A compressor typically for use in a turbocharger comprises a downstream radial compressor impeller wheel, an upstream axial compressor impeller wheel and an intermediate stator. The compressor housing has an inlet with inner and outer walls that define between them an MWE gas flow passage. An upstream opening defined by the flow passage provides communication between said passage and the intake and at least one first slot downstream of the upstream opening provides communication between the passage and the inner surface of the inner wall. The stator comprises a plurality of fixed vanes and is disposed in the inner wall of the inlet between the radial and axial impeller wheels. The position of the slot can be at one of several positions along the gas flow passage, hi other embodiments there are second and third slots and the flow passage is divided into two parts. All the arrangements are designed to improve the compressor map width.

A control apparatus of a supercharging system for supplying an engine with compressed intake air, includes: a supercharger including a compressor configured to compress the intake air to be supplied to the engine; and a controller for controlling a control device affecting operation of the compressor. The controller includes: a compressor map storage part configured to store a compressor map which indicates a relationship of an intake volume flow rate, a pressure ratio, and a compressor rotation speed in the compressor; a current position calculation part configured to calculate a current position of an operational point of the compressor on the compressor map every predetermined period; a moving direction calculation part configured to calculate a moving direction of the operational point on the compressor map on the basis of the current position of the operational point calculated by the current position calculation part; and a control part configured to control the control device on the basis of the current position of the operational point calculated by the current position calculation part and the moving direction of the operational point calculated by the moving direction calculation part.