System and method to align variable diffuser vane with direction of flow of working fluid

Abstract

Embodiments of systems and methods permit use of variable diffuser vanes in multi-stage compressor devices. These embodiments deploy a flow sensor to identify the direction of flow for a working fluid that transits the stages of the compressor device. In one embodiment, the flow sensor generates a signal, which a controller processes to align a variable diffuser vane with the direction of flow of the working fluid. This configuration pre-empts the operational difficulties of previous designs by providing independent control over the diffuser vanes in the individual stages of the multi-stage compressor device.

What is claimed is: 
     
         1 . A system, comprising:
 a compressor device comprising a first diffuser vane, a second diffuser vane downstream of the first diffuser vane, and a flow sensor assembly comprising a first flow sensor upstream of the first diffuser vane and a second flow sensor upstream of the second diffuser vane; and   a controller coupled with the first flow sensor and the second flow sensor, the controller comprising a processor, memory, and one or more executable instructions stored on the memory and configured to be executed by the processor, the executable instructions comprising instructions for:
 receiving a first signal from the first flow sensor encoding information that identifies a first direction of flow for a working fluid upstream of the first diffuser vane; 
 receiving a second signal from the second flow sensor encoding information that identifies a second direction of flow for the working fluid upstream of the second diffuser vane; 
 identifying a first position for the first diffuser vane and the second diffuser vane, the first position aligning the first diffuser vane and the second diffuser vane with, respectively, the first direction and the second direction of the working fluid; and 
 generating an output encoding instructions to move the first diffuser vane and the second diffuser vane to the first position. 
   
     
     
         2 . The system of  claim 1 , wherein the compressor device comprises a first actuator coupled with the first diffuser vane and a second actuator coupled with the second diffuser vane, and wherein the first actuator and the second actuator operate in response to the output. 
     
     
         3 . The system of  claim 1 , wherein the first flow sensor and the second flow sensor comprise a directional element and a base element coupled to the directional element, and wherein the information of the first signal and the second signal reflects an angular position of the directional element. 
     
     
         4 . The system of  claim 3 , wherein the base element comprises a rotary potentiometer that measures the angular position of the directional element. 
     
     
         5 . The system of  claim 1 , wherein the compressor device comprises a first impeller upstream of the first diffuser vane and a second impeller downstream of the first diffuser vane and upstream of the second diffuser vane. 
     
     
         6 . The system of  claim 1 , wherein the first diffuser vane and the second diffuser vane rotate in response to the output. 
     
     
         7 . The system of  claim 1 , wherein the first diffuser vane and the second diffuser vane have an airfoil shape that converges at the leading edge to a tip with a center axis, wherein the tip has a curvilinear outer surface defined by a radius from the center axis, and wherein the first diffuser vane and the second diffuser vane rotate about a rotation axis that is found within an area defined by the radius. 
     
     
         8 . The system of  claim 7 , wherein the rotation axis is coaxial with the center axis of the tip. 
     
     
         9 . The system of  claim 1 , wherein the executable instructions comprise instructions for:
 comparing the first direction and the second direction to, respectively, a first reference direction and a second reference direction; and   selecting a first increment by which to move the first diffuser vane and a second increment by which to move the second diffuser vane, the first increment defining the relative position of the first direction with respect to the first reference direction and the second increment defining the relative position of the second direction with respect to the second reference direction,   wherein the instructions cause the first diffuser vane and the second diffuser vane to move from the first position to a second position, and wherein the second position is defined relative to the first position for the first diffuser vane by the first increment and for the second diffuser vane by the second increment.   
     
     
         10 . A compressor device, comprising:
 a first diffuser vane;   a second diffuser vane downstream of the first diffuser vane;   a flow sensor assembly comprising a first flow sensor upstream of the first diffuser vane and a second flow sensor downstream of the first diffuser vane and upstream of the second diffuser vane, the first flow sensor and the second flow sensor comprising a base element and a directional element coupled with the base element, wherein the directional element can move between a first position and a second position to align with a flow of a working fluid.   
     
     
         11 . The compressor device of  claim 10 , wherein the base element provides a pivot about which the directional element can rotate between the first position and the second position. 
     
     
         12 . The compressor device of  claim 10 , wherein the base element comprises a rotary potentiometer. 
     
     
         13 . The compressor device of  claim 10 , wherein the first diffuser vane and the second diffuser vane comprise a vane body with a leading edge and a trailing edge and a rotation axis spaced apart from the leading edge and the trailing edge along a chord length that defines the straight-line distance between the leading edge and the trailing edge 
     
     
         14 . The compressor device of  claim 10 , wherein the first diffuser vane and the second diffuser vane rotate about the leading edge. 
     
     
         15 . The compressor device of  claim 10 , wherein the vane body has an airfoil shape that converges at the leading edge to a tip with a center axis, wherein the tip has a curvilinear outer surface defined by a radius from the center axis, and wherein the first diffuser vane and the second diffuser vane rotate about a rotation axis that is found within an area defined by the radius. 
     
     
         16 . The compressor device of  claim 16 , wherein the rotation axis is coaxial with the center axis of the tip. 
     
     
         17 . The compressor device of  claim 10 , further comprising a controller coupled with the first flow sensor and the second flow sensor, the controller comprising a processor, memory, and one or more executable instructions stored on the memory and configured to be executed by the processor, the executable instructions comprising instructions for:
 receiving a first signal from the first flow sensor encoding information that identifies a first direction of flow for a working fluid upstream of the first diffuser vane;   receiving a second signal from the second flow sensor encoding information that identifies a second direction of flow for the working fluid upstream of the second diffuser vane;   identifying a first position for the first diffuser vane and the second diffuser vane, the first position aligning the first diffuser vane and the second diffuser vane with, respectively, the first direction and the second direction of the working fluid; and   generating an output encoding instructions to move the first diffuser vane and the second diffuser vane to the first position.   
     
     
         18 . The compressor device of  claim 17 , wherein the executable instructions comprise instructions for:
 comparing the first direction and the second direction to, respectively, a first reference direction and a second reference direction; and   selecting a first increment by which to move the first diffuser vane and a second increment by which to move the second diffuser vane, the first increment defining the relative position of the first direction with respect to the first reference direction and the second increment defining the relative position of the second direction with respect to the second reference direction,   wherein the instructions cause the first diffuser vane and the second diffuser vane to move from the first position to a second position, and wherein the second position is defined relative to the first position for the first diffuser vane by the first increment and for the second diffuser vane by the second increment.   
     
     
         19 . A controller for operating a compressor device, said controller comprising:
 a processor;   memory; and   executable instructions stored on the memory and configured to be executed by the processor, the executable instructions comprising instructions for:
 receiving a first signal from the first flow sensor encoding information that identifies a first direction of flow for a working fluid upstream of the first diffuser vane; 
 receiving a second signal from the second flow sensor encoding information that identifies a second direction of flow for the working fluid upstream of the second diffuser vane; 
 identifying a first position for the first diffuser vane and the second diffuser vane, the first position aligning the first diffuser vane and the second diffuser vane with, respectively, the first direction and the second direction of the working fluid; and 
 generating an output encoding instructions to move the first diffuser vane and the second diffuser vane to the first position. 
   
     
     
         20 . The controller of  claim 19 , further comprising instructions for:
 comparing the first direction and the second direction to, respectively, a first reference direction and a second reference direction, wherein the first reference direction and the second reference direction comprise a value for the first direction and the second direction at a time t, and wherein the first position; and   selecting a first increment by which to move the first diffuser vane and a second increment by which to move the second diffuser vane, the first increment defining the relative position of the first direction with respect to the first reference direction and the second increment defining the relative position of the second direction with respect to the second reference direction,   wherein the instructions cause the first diffuser vane and the second diffuser vane to move from the first position to a second position, and wherein the second position is defined relative to the first position for the first diffuser vane by the first increment and for the second diffuser vane by the second increment.