A diffuser system for a centrifugal compressor is provided. The diffuser system includes a nozzle base plate that defines a diffuser gap, support blocks, and a drive ring rotatable relative to the support blocks. The drive ring includes cam tracks and bearing assemblies positioned proximate an outer circumference of the drive ring. The diffuser system further includes drive pins extending through the support blocks and the nozzle base plate. The first end of each drive pin includes a cam follower mounted into a cam track on the drive ring. The second end of each drive pin is coupled to a diffuser ring. Rotation of the drive ring causes axial movement of the drive pins by movement of the cam followers in the cam tracks. This results in movement of the diffuser ring to control fluid flow through the diffuser gap.

A control system is provided to optimize a compressor that has a variable guide vane position and a variable speed set point. One or more controllers receive a process set point for a main process variable for a first performance control application and a deviation set point for a surge deviation level for a second performance control application. The first performance control application operates a first independent primary control loop to control the main process variable at the process set point by manipulating the variable guide vane position. The second performance control application operates a second independent primary control loop to control a surge deviation level at the deviation set point by manipulating the variable speed set point. The second performance control application also executes a limit control loop to limit the main process variable at a limit set point by manipulating the variable speed set point.

This disclosure describes a novel methodology for anti-surge and anti-choke control systems protecting centrifugal and axial compressors. The methodology, based on Buckingham's π-theorem for compressors, presents compressor performance maps in dimensionless rectangular π-term coordinates that are independent of compressor inlet conditions, fluid molecular weight and rotational speed. The full range of compressor operating points from surge to choke is monitored and controlled when surge and choke limits are available. This is accomplished by converting rectangular coordinates presented in π-terms to polar coordinates, and then converting them to a controlled variable used in the closed-loop controllers. The methodology provides control algorithms for variable speed compressors, variable geometry compressors equipped with inlet guide vanes or stator vanes that exhibit displacement of surge and choke limits. The methodology most accurately estimates the location of the operating point relative to its limit in polar coordinates if only the surge or choke limit is available. The presented protection methods are applicable to any known types of dynamic compressors for industrial, commercial, jet engines, turbochargers.

A number of variations may include a method comprising selectively actuating an inlet swirl device to cause a compressor to windmill at a higher speed during an operation mode where fuel consumption of an engine in the vehicle is at a minimal or before an acceleration event.

A compressor control system includes: a compressor; an inlet guide vane (IGV) arranged at an inlet of the compressor, and configured to adjust opening of the inlet based on a supplementary surge control signal or a performance control signal; an anti-surge valve (ASV) connected to an outlet of the compressor, and configured to prevent a surge based on a surge control signal; and a controller configured to generate the surge control signal for controlling the ASV when an operating point enters a surge control range, generate the supplementary surge control signal for controlling the IGV in an anti-surge mode when the operating point enters a supplementary surge control range set between the surge control range and a surge range, and generate the performance control signal for controlling the IGV in a performance mode until the operating point enters the surge control range.

A system includes a dynamic compressor and a controller having a processor and a memory. The compressor includes a first compressor stage having a first variable inlet guide vane (VIGV) and a second compressor stage having a second VIGV. The memory stores instructions that program the processor to operate the compressor at a current speed, a first position of the first VIGV, and a second position of the second VIGV to compress the working fluid, and to determine if a condition is satisfied. If the condition is not satisfied, the processor is programmed to continue to operate the compressor at the current speed, the first position of the first VIGV, and the second position of the second VIGV. If the condition is satisfied, the processor is programmed to change the second position of the second VIGV to a third position and maintain the first position of the first VIGV.

A casing treatment for a compressor includes one or more cavities in a casing disposed radially outwardly of tips of the compressor rotor blades. A liner is moveable relative to the casing between a first position and a second position. The liner is shaped to add a volume to the tip clearance gap when moving from the second position toward the first position. The liner is displaceable between the first and second positions in coordination with at least the rotation of inlet guide vanes (IGVs) between IGV positions.

An illustrative example embodiment of a compressor includes an inlet defining an intake passage, a plurality of lateral inlet guide vanes in the intake passage, and a plurality of medial inlet guide vanes in the intake passage. The lateral guide vanes are selectively oriented to alter an amount of fluid flow through a first, lateral portion of the intake passage. The medial inlet guide vanes are selectively oriented to alter an amount of fluid flow through a second, medial portion of the intake passage.

A heat transfer circuit includes a compressor, a condenser, an expander, and an evaporator that are fluidly connected together. The compressor includes a housing and a shaft rotatable relative to the housing to compress a working fluid received at a suction inlet, in which the shaft is supported by a gas bearing, and the gas bearing including a bearing housing having a fluid inlet and an outlet. A high pressure gas source is fluidly connected to the fluid inlet of the bearing housing for supplying high pressure fluid to the fluid inlet of the gas bearing such that the gas bearing supports the shaft when the shaft is rotating. A pressure reducer is connected to the outlet of the gas bearing is provided for reducing a vent pressure of the gas bearing.

Provided is a centrifugal compressor, including: a movable member which is movable between a first position and a second position, the first position being a position at which an opening degree of an auxiliary flow passage arranged more on an outer diameter side than a main flow passage becomes a first opening degree, the second position being a position at which an opening degree of the auxiliary flow passage becomes a second opening degree smaller than the first opening degree; and a linear actuator configured to drive the movable member in a rotation axis direction of the impeller.