WO2017040807A1 - Turbomachine anti-surge system - Google Patents
Turbomachine anti-surge system Download PDFInfo
- Publication number
- WO2017040807A1 WO2017040807A1 PCT/US2016/049939 US2016049939W WO2017040807A1 WO 2017040807 A1 WO2017040807 A1 WO 2017040807A1 US 2016049939 W US2016049939 W US 2016049939W WO 2017040807 A1 WO2017040807 A1 WO 2017040807A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- valve
- turbomachine
- controller
- actuator
- operations information
- Prior art date
Links
- 238000004891 communication Methods 0.000 claims description 42
- 239000012530 fluid Substances 0.000 claims description 25
- 238000000034 method Methods 0.000 claims description 21
- 239000007789 gas Substances 0.000 description 26
- 230000008569 process Effects 0.000 description 10
- 238000005259 measurement Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 230000009467 reduction Effects 0.000 description 3
- 230000006378 damage Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000001066 destructive effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000000246 remedial effect Effects 0.000 description 1
- 230000009528 severe injury Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0246—Surge control by varying geometry within the pumps, e.g. by adjusting vanes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/58—Cooling; Heating; Diminishing heat transfer
- F04D29/582—Cooling; Heating; Diminishing heat transfer specially adapted for elastic fluid pumps
- F04D29/5826—Cooling at least part of the working fluid in a heat exchanger
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D17/00—Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
- F04D17/08—Centrifugal pumps
- F04D17/10—Centrifugal pumps for compressing or evacuating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0207—Surge control by bleeding, bypassing or recycling fluids
- F04D27/0215—Arrangements therefor, e.g. bleed or by-pass valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0207—Surge control by bleeding, bypassing or recycling fluids
- F04D27/0223—Control schemes therefor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
- F04D29/284—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps for compressors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/44—Fluid-guiding means, e.g. diffusers
- F04D29/441—Fluid-guiding means, e.g. diffusers especially adapted for elastic fluid pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2270/00—Control
- F05D2270/01—Purpose of the control system
- F05D2270/10—Purpose of the control system to cope with, or avoid, compressor flow instabilities
- F05D2270/101—Compressor surge or stall
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2270/00—Control
- F05D2270/60—Control system actuates means
- F05D2270/62—Electrical actuators
Definitions
- This specification relates to turbomachine control and protection systems.
- Compressors increase the pressure on a fluid. As gases are compressible, the compressor also reduces the volume of a gas.
- a compressor stall is a local disruption of the airflow in a gas turbine or turbocharger compressor.
- Axi-symmetric stall also known as compressor surge, is a breakdown in compression resulting in a reversal of flow and the violent expulsion of previously compressed gas out in the direction of the compressor intake. This condition is a result of the compressor's inability to continue working against the already-compressed gas behind it. As a result, the compressor may experience conditions that exceed its pressure rise capabilities, or the compressor may become loaded such that a flow reversal occurs, which can propagate in less than a second to include the entire compressor.
- a compressor anti-surge system comprises a first actuator configured to actuate a first valve of a first turbomachine, and a first controller at least partially integrated with the first actuator or the first valve, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine.
- the first actuator is configured to actuate the first valve through a mechanical coupler or a fluid circuit.
- the compressor anti-surge system further comprises a first field sensor configured to sense a first turbomachine parameter of the first turbomachine, wherein the first controller is further configured to receive the first turbomachine parameter from the first field sensor and perform at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter.
- the valve is a sliding stem turbomachinery control valve, rotary turbomachinery control valve, or a guide vane.
- the compressor anti-surge system further comprises an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve.
- the first controller further comprises a first communication port and is configured to provide controller operations information through the first communications port, a second actuator configured to actuate a second valve of a second
- turbomachine and a second controller at least partially integrated with the second actuator or the second valve, a second communication port configured to communicate with the first communication port and receive controller operations information, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the second
- turbomachine based at least in part on the received controller operations information.
- the first controller further comprises a first communication port and is configured to provide controller operations information through the first communications port, a second actuator configured to actuate a second valve of the first
- turbomachine and a second controller at least partially integrated with the second actuator or the second valve, a second communication port configured to communicate with the first communication port and receive controller operations information, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine based at least in part on the received controller operations information.
- a method of responding to compressor surge comprises receiving at a first controller at least partially integrated with a first valve and from a first field sensor a first turbomachine parameter of a first turbomachine, determining by the first controller at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter, and actuating by a first actuator at least partially integrated with the first valve or the first controller the first valve to perform the determined control operation or protection operation for the first turbomachine.
- the first actuator is configured to actuate the first valve through a mechanical coupler or a fluid circuit.
- the valve is a sliding stem turbomachinery control valve, rotary turbomachinery control valve, or a guide vane.
- At least one of the control operation or the protection operation for the first turbomachine comprises actuating the first valve to control flow of fluids to an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve.
- the method further comprises providing by the first controller operations information through a first communications port, receiving at a second communications port of a second controller at least partially integrated with a second valve of a second turbomachine or a second actuator configured to actuate the second valve the controller operations information, and actuating by the second actuator the second valve perform at least one of a control operation or a protection operation for the second turbomachine based at least in part on the received controller operations information.
- the method further comprises providing by the first controller operations information through a first communications port, receiving at a second communications port of a second controller at least partially integrated with a second valve of the first turbomachine or a second actuator configured to actuate the second valve the controller operations information, and actuating by the second actuator the second valve perform at least one of a control operation or a protection operation for the first turbomachine based at least in part on the received controller operations information.
- a system can widen the turbomachine operating envelope.
- the system can increase turbomachine safety.
- the system can reduce of the effective valve size.
- the system can reduce process time lags in the anti-surge system.
- the system can improve the reliability and predictability of turbomachine system dynamic performance.
- FIG. 1 is a schematic diagram that shows an example of a prior art turbomachine system
- FIG. 2 is a schematic diagram that shows an example of a compressor system.
- FIG. 3 is flow chart that shows an example of a process for protecting a turbomachine system.
- turbomachine anti-surge systems described in the descriptions of FIGs. 2-3 combine all or some of one or more fast, high dynamic performance electrically actuated anti-surge valves, electronic controls fully or partially integrated into the valve assembly and executing surge prevention and surge protection control algorithms, compact heat exchangers adjacent to the anti-surge valves to cool the medium flowing through the anti-surge valves, and reducing process time lag in the anti-surge control loop.
- Compressor systems as commonly used in gas transmission compressor stations, petro-chemical refining and processing installations, for example, can undergo a potentially destructive phenomenon called "surge".
- the operational status of compressor systems can be represented by an operating map with axes representing changes in pressure (deltaP) and changes in flow (deltaQ).
- the operating point of the compressor Upon further reduction of the flow-rate, the operating point of the compressor will oscillate between a point left and right of this surge line. The oscillation can cause undesired motion of the compressor blades and the drive shaft such that the blades contact the stators within the compressor which can cause catastrophic damage in a very short time period.
- FIG. 1 is a schematic diagram that shows an example of a prior art turbomachine system 100.
- the turbomachine system 100 is illustrated as a centrifugal compressor that includes a compressor 102a and a compressor 102b that are driven by a prime mover 104 (e.g., a motor).
- the compressors 102a, 102b pressurize a gas received at an inlet 106 (e.g., a suction port) and discharge the pressurized gas at a discharge 108 (e.g., an outlet port).
- a process gas cooler 107 e.g., a heat exchanger
- the system 100 commonly includes a controller 1 10, a hot recycle valve 1 12 controlling forward flow along a hot recycle conduit 1 14, a cold recycle valve 1 16 controlling return flow along a cold recycle conduit 1 18, and an actuator bypass loop with a gas inter-cooler 107 (heat exchanger).
- a fluid actuator 1 13 e.g., hydraulic, pneumatic is configured to actuate the hot recycle valve 1 12, and a fluid actuator 1 17 is configured to actuate the cold recycle valve 1 16.
- the controller 1 10 is configured to monitor either one or a plurality of a collection of surge parameter values.
- the surge parameter values are based on measurement signals received from a collection of system sensors and feedback devices.
- the controller 1 10 receives measurement signals from a flow sensor 130a, a suction pressure sensor 130b, and a discharge pressure sensor 130c.
- the controller 1 10 may directly or indirectly control a safeguard operation. For example, the controller 1 10 may trigger compressed gas at the discharge 108 to flow back to the inlet 106 through the cold recycle valve 1 16 to relieve the surge condition. In another example, the controller 1 10 may trigger uncompressed gas at the inlet 106 to flow forward to the discharge 108 through the hot recycle valve 1 12 to relieve the surge condition.
- FIG. 2 is a schematic diagram that shows an example of a compressor system 200.
- the turbomachine system 200 is illustrated as a centrifugal compressor that includes a compressor 202a and a
- compressor 202b that are driven by a prime mover 204 (e.g., a motor).
- the compressors 202a, 202b pressurize a gas received at an inlet 206 (e.g., a suction port) and discharges the pressurized gas at a discharge 208 (e.g., an outlet port).
- a process gas cooler 207 e.g., a heat exchanger cools the gas before it flows out a discharge 209.
- a flow sensor 230a is configured to measure inlet gas flow.
- a suction pressure sensor 230b is configured to measure gas pressure at the inlet 206.
- a discharge pressure sensor 230c is configured to measure gas pressure at the discharge 208.
- the inlet 206 is in fluid communication with the discharge 208 through a recycle valve 212 and a gas cooler 250 (e.g., heat exchanger).
- the recycle valve can be a sliding stem turbomachinery control valve, a rotary turbomachinery control valve, a guide vane, or any other appropriate turbomachine valve.
- an electric actuator 213 is configured to actuate the recycle valve 212.
- the electric actuator 213 is an all- electric, high performance actuator.
- the electric actuator 213 can start moving the recycle valve 212 more quickly (e.g., about 25 mS typical) than is possible with the fluid actuators 1 13 and 1 17 of FIG. 1 .
- the electric actuator 213 can move the recycle valve 212 from closed to fully open in about 0.3 to 0.6 seconds, although in some embodiments longer times may occur when actuating larger valves.
- the electric actuator 213 may actuate the recycle valve 212 through a mechanical coupler or a fluid circuit.
- use of the electric actuator 213, rather than the relatively slower fluid actuators 1 13 and 1 17 of FIG. 1 allows the compressor system 200 to be operated more efficiently than the compressor system 100.
- the closer that the compressor systems 100, 200 can be operated on the operating map to the deltaP/deltaQ surge line without actually reaching zero the more efficient the compressor systems 100, 200 can be.
- safety margins away from the surge line are generally used. The magnitudes of these safety margins are at least partly proportional to the amount of time needed for their corresponding compressor systems to take corrective, anti-surge actions before deltaP/deltaQ reaches zero.
- the recycle valve 212 can be a high turn down valve that can be modulated near the fully closed position without causing damage to the internal metering elements of the recycle valve 212 due to high throttling conditions.
- the recycle valve 212 can includes noise reduction trim, either within the recycle valve 212 or externally, depending upon operational requirements.
- the electric actuator 213 of the example compressor system 200 includes an at least partly integrated anti-surge controller configured to receive surge parameter values, calculate proximity to surge control line, and take corrective control actions.
- the surge parameter values are based on measurement signals received from a collection of system sensors and feedback devices.
- the electric actuator 213 receives measurement signals from the sensors 230a-230c.
- the electric actuator 213 of the example compressor system 200 includes an at least partly integrated surge detection system configured to receive surge parameter values, detect surge conditions, and/or take corrective safety actions.
- the surge parameter values are based on measurement signals received from a collection of system sensors and feedback devices.
- the electric actuator 213 receives measurement signals from the sensors 230a-230c.
- different and/or additional sensors may be used (e.g., temperature, torque, speed, vibration).
- the fully integrated surge controller of the electric actuator 213 of the example compressor system 200 is programmed and dynamically matched to the characteristics of the recycle valve 212 and the flow measurement system of the example compressor system 200 (e.g., the sensors 230a-230c) such that the total system dynamics of the compressor system 200 are well controlled and predictable.
- the electric actuator 213 may directly or indirectly control a safeguard operation.
- the electric actuator can actuate the recycle valve 212 to allow compressed gas at the discharge 208 to flow back to the inlet 206 through the recycle valve 212 and the gas cooler 250 to relieve the surge condition.
- the electric actuator 213 may provide signals that can be used to trigger other remedial actions, for example, such as a controlled reduction or shutdown of the prime mover 204.
- the electric actuator 213 may also include functions such as surge control, choke control, steam turbine extraction control, gas turbine speed control, steam turbine speed control, compressor guide vane capacity control, compressor inlet throttle valve capacity control, or combinations of these and/or any other appropriate functions for compressor system control.
- the surge controller of the electric actuator 213 can include a communication port that is configured to provide controller operations information through the communications port.
- a second actuator can be configured to actuate a second valve of a second turbomachine, and a second controller can be at least partially integrated with the second actuator or the second valve.
- the second controller can include a second
- the communication port configured to communicate with the first communication port and receive controller operations information, and include circuitry configured to perform at least one of a control operation or a protection operation for the second turbomachine based at least in part on the received controller operations information.
- the electric actuator 213 may provide information to an electric actuator of another compressor system.
- the surge controller of the electric actuator 213 can include a communication port that is configured to provide controller operations information through the communications port.
- a second actuator can be configured to actuate a second valve of the compressor system 200, and a second controller can be at least partially integrated with the second actuator or the second valve.
- the second controller can include a second communication port configured to communicate with the first communication port and receive controller operations information, and include circuitry configured to perform at least one of a control operation or a protection operation for the compressor system 200 based at least in part on the received controller operations information.
- FIG. 3 is flow chart that shows an example of a process 300 for protecting a turbomachine system.
- the process 300 can be used to protect the example compressor system 200 of FIG. 2.
- a first controller at least partially integrated with a first valve receives a first turbomachine parameter of a first turbomachine from a first field sensor.
- the compressor system 200 includes the electric actuator 213 which is configured to receive feedback from the sensors 230a- 230c.
- the first controller determines at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter.
- the electric actuator 213 can receive feedback from the sensors 230a-230c and determine that a surge event is underway (e.g., deltaP/deltaQ is within the predetermined safety margin around the surge line).
- the first actuator at least partially integrated with the first valve or the first controller actuates the first valve to perform the determined control operation or protection operation for the first turbomachine.
- the electric actuator 213 can actuate the recycle valve 212 in an attempt to remedy the surge condition.
- at least one of the control operation or the protection operation for the first turbomachine can include actuating the first valve to control flow of fluids to an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve.
- the recycle valve 212 can be actuated to allow compressed gasses to pass through the gas cooler 250 and on to the inlet 206.
- the process 300 can include providing, by the first controller, controller operations information through a first
- the electric actuator 213 can provide control signals to another electric actuator of another compressor system 200 to cause another recycle valve to be actuated.
- the process 300 can include providing, by the first controller, controller operations information through a first
- the electric actuator 213 can provide control signals to another electric actuator of the compressor system 200 to cause another recycle valve of the compressor system 200 to be actuated.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Geometry (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
Abstract
The subject matter of this specification can be embodied in, among other things, a compressor anti-surge system that includes a first actuator configured to actuate a first valve of a first turbomachine, and a first controller at least partially integrated with the first actuator or the first valve, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine.
Description
Turbomachine Anti-Surge System
CLAIM OF PRIORITY
[0001] This application claims priority to U.S. Patent Application No.
14/843,486 filed on September 2, 2015, the entire contents of which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] This specification relates to turbomachine control and protection systems.
BACKGROUND
[0003] Compressors increase the pressure on a fluid. As gases are compressible, the compressor also reduces the volume of a gas. A compressor stall is a local disruption of the airflow in a gas turbine or turbocharger compressor. Axi-symmetric stall, also known as compressor surge, is a breakdown in compression resulting in a reversal of flow and the violent expulsion of previously compressed gas out in the direction of the compressor intake. This condition is a result of the compressor's inability to continue working against the already-compressed gas behind it. As a result, the compressor may experience conditions that exceed its pressure rise capabilities, or the compressor may become loaded such that a flow reversal occurs, which can propagate in less than a second to include the entire compressor.
[0004] Once the compressor pressure ratio reduces to a level at which the compressor is capable of sustaining stable flow, the compressor will resume
normal flow. If the conditions that induced the stall remains, the process can repeat. Repeating surge events can be dangerous, since they can cause high levels of vibration, compressor component wear and possible severe damage to compressor bearings, seals, impellers and shaft, including consequential loss of containment and explosion of hazardous gas.
SUMMARY
[0005] In general, this document describes turbomachine protection systems.
[0006] In a first aspect, a compressor anti-surge system comprises a first actuator configured to actuate a first valve of a first turbomachine, and a first controller at least partially integrated with the first actuator or the first valve, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine.
[0007] In a second aspect, according to aspect 1 , the first actuator is configured to actuate the first valve through a mechanical coupler or a fluid circuit.
[0008] In a third aspect, according to any one of aspects 1 or 2, the compressor anti-surge system further comprises a first field sensor configured to sense a first turbomachine parameter of the first turbomachine, wherein the first controller is further configured to receive the first turbomachine parameter from the first field sensor and perform at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter.
[0009] In a fourth aspect, according to any one of aspects 1 to 3, the valve is a sliding stem turbomachinery control valve, rotary turbomachinery control valve, or a guide vane.
[0010] In a fifth aspect, according to any one of aspects 1 to 4, the compressor anti-surge system further comprises an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve.
[0011] Ina sixth aspect, according to any one of aspects 1 to 5, the first controller further comprises a first communication port and is configured to provide controller operations information through the first communications port, a second actuator configured to actuate a second valve of a second
turbomachine, and a second controller at least partially integrated with the second actuator or the second valve, a second communication port configured to communicate with the first communication port and receive controller operations information, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the second
turbomachine based at least in part on the received controller operations information.
[0012] In a seventh aspect, according to any one of aspects 1 to 6, the first controller further comprises a first communication port and is configured to provide controller operations information through the first communications port, a second actuator configured to actuate a second valve of the first
turbomachine, and a second controller at least partially integrated with the second actuator or the second valve, a second communication port configured
to communicate with the first communication port and receive controller operations information, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine based at least in part on the received controller operations information.
[0013] In an eighth aspect, a method of responding to compressor surge comprises receiving at a first controller at least partially integrated with a first valve and from a first field sensor a first turbomachine parameter of a first turbomachine, determining by the first controller at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter, and actuating by a first actuator at least partially integrated with the first valve or the first controller the first valve to perform the determined control operation or protection operation for the first turbomachine.
[0014] In a ninth aspect, according to aspect 8, the first actuator is configured to actuate the first valve through a mechanical coupler or a fluid circuit.
[0015] In a tenth aspect, according to any one of aspects 8 or 9, the valve is a sliding stem turbomachinery control valve, rotary turbomachinery control valve, or a guide vane.
[0016] In an eleventh aspect, according to any one of aspects 8 to 10, at least one of the control operation or the protection operation for the first turbomachine comprises actuating the first valve to control flow of fluids to an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve.
[0017] In a twelfth aspect, according to any one of aspects 8 to 1 1 , the method further comprises providing by the first controller operations information through a first communications port, receiving at a second communications port of a second controller at least partially integrated with a second valve of a second turbomachine or a second actuator configured to actuate the second valve the controller operations information, and actuating by the second actuator the second valve perform at least one of a control operation or a protection operation for the second turbomachine based at least in part on the received controller operations information.
[0018] In a thirteenth aspect, according to any one of aspects 8 to 12, the method further comprises providing by the first controller operations information through a first communications port, receiving at a second communications port of a second controller at least partially integrated with a second valve of the first turbomachine or a second actuator configured to actuate the second valve the controller operations information, and actuating by the second actuator the second valve perform at least one of a control operation or a protection operation for the first turbomachine based at least in part on the received controller operations information.
[0019] The systems and techniques described here may provide one or more of the following advantages. First, a system can widen the turbomachine operating envelope. Second, the system can increase turbomachine safety. Third, the system can reduce of the effective valve size. Fourth, the system can reduce process time lags in the anti-surge system. Fifth, the system can
improve the reliability and predictability of turbomachine system dynamic performance.
[0020] The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a schematic diagram that shows an example of a prior art turbomachine system
[0022] FIG. 2 is a schematic diagram that shows an example of a compressor system.
[0023] FIG. 3 is flow chart that shows an example of a process for protecting a turbomachine system.
DETAILED DESCRIPTION
[0024] This document describes systems and techniques for reducing turbomachine surge. In general, the turbomachine anti-surge systems described in the descriptions of FIGs. 2-3 combine all or some of one or more fast, high dynamic performance electrically actuated anti-surge valves, electronic controls fully or partially integrated into the valve assembly and executing surge prevention and surge protection control algorithms, compact heat exchangers adjacent to the anti-surge valves to cool the medium flowing through the anti-surge valves, and reducing process time lag in the anti-surge control loop.
[0025] Compressor systems, as commonly used in gas transmission compressor stations, petro-chemical refining and processing installations, for example, can undergo a potentially destructive phenomenon called "surge". The operational status of compressor systems can be represented by an operating map with axes representing changes in pressure (deltaP) and changes in flow (deltaQ). Surge occurs when, at a certain compressor head, the flow-rate is reduced to the extent that the operating conditions approach the points along the operating map where deltaP/deltaQ = 0. These points appear on the operating map as a line sometimes referred to as the "surge line". Upon further reduction of the flow-rate, the operating point of the compressor will oscillate between a point left and right of this surge line. The oscillation can cause undesired motion of the compressor blades and the drive shaft such that the blades contact the stators within the compressor which can cause catastrophic damage in a very short time period.
[0026] FIG. 1 is a schematic diagram that shows an example of a prior art turbomachine system 100. In FIG. 1 , the turbomachine system 100 is illustrated as a centrifugal compressor that includes a compressor 102a and a compressor 102b that are driven by a prime mover 104 (e.g., a motor). The compressors 102a, 102b pressurize a gas received at an inlet 106 (e.g., a suction port) and discharge the pressurized gas at a discharge 108 (e.g., an outlet port). A process gas cooler 107 (e.g., a heat exchanger) cools the gas before it flows out a discharge 109.
[0027] To prevent surge conditions, the system 100 commonly includes a controller 1 10, a hot recycle valve 1 12 controlling forward flow along a hot
recycle conduit 1 14, a cold recycle valve 1 16 controlling return flow along a cold recycle conduit 1 18, and an actuator bypass loop with a gas inter-cooler 107 (heat exchanger).. A fluid actuator 1 13 (e.g., hydraulic, pneumatic) is configured to actuate the hot recycle valve 1 12, and a fluid actuator 1 17 is configured to actuate the cold recycle valve 1 16.
[0028] The controller 1 10 is configured to monitor either one or a plurality of a collection of surge parameter values. The surge parameter values are based on measurement signals received from a collection of system sensors and feedback devices. In the illustrated example, the controller 1 10 receives measurement signals from a flow sensor 130a, a suction pressure sensor 130b, and a discharge pressure sensor 130c.
[0029] If the controller 1 10 determines that a surge event is occurring, the controller 1 10 may directly or indirectly control a safeguard operation. For example, the controller 1 10 may trigger compressed gas at the discharge 108 to flow back to the inlet 106 through the cold recycle valve 1 16 to relieve the surge condition. In another example, the controller 1 10 may trigger uncompressed gas at the inlet 106 to flow forward to the discharge 108 through the hot recycle valve 1 12 to relieve the surge condition.
[0030] FIG. 2 is a schematic diagram that shows an example of a compressor system 200. In FIG. 2, the turbomachine system 200 is illustrated as a centrifugal compressor that includes a compressor 202a and a
compressor 202b that are driven by a prime mover 204 (e.g., a motor). The compressors 202a, 202b pressurize a gas received at an inlet 206 (e.g., a suction port) and discharges the pressurized gas at a discharge 208 (e.g., an
outlet port). A process gas cooler 207 (e.g., a heat exchanger) cools the gas before it flows out a discharge 209.
[0031] A flow sensor 230a is configured to measure inlet gas flow. A suction pressure sensor 230b is configured to measure gas pressure at the inlet 206. A discharge pressure sensor 230c is configured to measure gas pressure at the discharge 208. The inlet 206 is in fluid communication with the discharge 208 through a recycle valve 212 and a gas cooler 250 (e.g., heat exchanger). In some embodiments, the recycle valve can be a sliding stem turbomachinery control valve, a rotary turbomachinery control valve, a guide vane, or any other appropriate turbomachine valve.
[0032] In the example compressor system 200, an electric actuator 213 is configured to actuate the recycle valve 212. The electric actuator 213 is an all- electric, high performance actuator. In some embodiments, the electric actuator 213 can start moving the recycle valve 212 more quickly (e.g., about 25 mS typical) than is possible with the fluid actuators 1 13 and 1 17 of FIG. 1 . In some embodiments, the electric actuator 213 can move the recycle valve 212 from closed to fully open in about 0.3 to 0.6 seconds, although in some embodiments longer times may occur when actuating larger valves. In some embodiments, the electric actuator 213 may actuate the recycle valve 212 through a mechanical coupler or a fluid circuit.
[0033] In some embodiments, use of the electric actuator 213, rather than the relatively slower fluid actuators 1 13 and 1 17 of FIG. 1 allows the compressor system 200 to be operated more efficiently than the compressor system 100. In general, the closer that the compressor systems 100, 200 can
be operated on the operating map to the deltaP/deltaQ surge line without actually reaching zero, the more efficient the compressor systems 100, 200 can be. However, to prevent the flow-rate from being reduced to the extent that the operating conditions actually reach a point along the operating map where deltaP/deltaQ = 0, safety margins away from the surge line are generally used. The magnitudes of these safety margins are at least partly proportional to the amount of time needed for their corresponding compressor systems to take corrective, anti-surge actions before deltaP/deltaQ reaches zero. Use of the electric actuator 213 reduces the amount of time needed to respond to conditions that are indicative of surge (e.g., compared to the fluid actuators 1 13 and 1 17), and allows the compressor system 200 to be operated safely closer to the surge line. By operating closer to where deltaP/deltaQ = 0, the compressor system 200 can operate more efficiently than the compressor system 100.
[0034] In some embodiments, the recycle valve 212 can be a high turn down valve that can be modulated near the fully closed position without causing damage to the internal metering elements of the recycle valve 212 due to high throttling conditions. In some embodiments, the recycle valve 212 can includes noise reduction trim, either within the recycle valve 212 or externally, depending upon operational requirements.
[0035] To prevent surge conditions, the electric actuator 213 of the example compressor system 200 includes an at least partly integrated anti-surge controller configured to receive surge parameter values, calculate proximity to surge control line, and take corrective control actions. The surge parameter
values are based on measurement signals received from a collection of system sensors and feedback devices. In the illustrated example, the electric actuator 213 receives measurement signals from the sensors 230a-230c.
[0036] To protect compressor from repeated surge, the electric actuator 213 of the example compressor system 200 includes an at least partly integrated surge detection system configured to receive surge parameter values, detect surge conditions, and/or take corrective safety actions. The surge parameter values are based on measurement signals received from a collection of system sensors and feedback devices. In the illustrated example, the electric actuator 213 receives measurement signals from the sensors 230a-230c. In some embodiments, different and/or additional sensors may be used (e.g., temperature, torque, speed, vibration).
[0037] The fully integrated surge controller of the electric actuator 213 of the example compressor system 200 is programmed and dynamically matched to the characteristics of the recycle valve 212 and the flow measurement system of the example compressor system 200 (e.g., the sensors 230a-230c) such that the total system dynamics of the compressor system 200 are well controlled and predictable.
[0038] If the electric actuator 213 determines that a surge event is occurring, the electric actuator 213 may directly or indirectly control a safeguard operation. For example, the electric actuator can actuate the recycle valve 212 to allow compressed gas at the discharge 208 to flow back to the inlet 206 through the recycle valve 212 and the gas cooler 250 to relieve the surge condition. In another example, the electric actuator 213 may provide
signals that can be used to trigger other remedial actions, for example, such as a controlled reduction or shutdown of the prime mover 204. In some embodiments, the electric actuator 213 may also include functions such as surge control, choke control, steam turbine extraction control, gas turbine speed control, steam turbine speed control, compressor guide vane capacity control, compressor inlet throttle valve capacity control, or combinations of these and/or any other appropriate functions for compressor system control.
[0039] In some embodiments, the surge controller of the electric actuator 213 can include a communication port that is configured to provide controller operations information through the communications port. A second actuator can be configured to actuate a second valve of a second turbomachine, and a second controller can be at least partially integrated with the second actuator or the second valve. The second controller can include a second
communication port configured to communicate with the first communication port and receive controller operations information, and include circuitry configured to perform at least one of a control operation or a protection operation for the second turbomachine based at least in part on the received controller operations information. For example, the electric actuator 213 may provide information to an electric actuator of another compressor system.
[0040] In some embodiments, the surge controller of the electric actuator 213 can include a communication port that is configured to provide controller operations information through the communications port. A second actuator can be configured to actuate a second valve of the compressor system 200, and a second controller can be at least partially integrated with the second
actuator or the second valve. The second controller can include a second communication port configured to communicate with the first communication port and receive controller operations information, and include circuitry configured to perform at least one of a control operation or a protection operation for the compressor system 200 based at least in part on the received controller operations information.
[0041] FIG. 3 is flow chart that shows an example of a process 300 for protecting a turbomachine system. In some implementations, the process 300 can be used to protect the example compressor system 200 of FIG. 2.
[0042] At 310, a first controller at least partially integrated with a first valve receives a first turbomachine parameter of a first turbomachine from a first field sensor. For example, the compressor system 200 includes the electric actuator 213 which is configured to receive feedback from the sensors 230a- 230c.
[0043] At 320, the first controller determines at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter. For example, the electric actuator 213 can receive feedback from the sensors 230a-230c and determine that a surge event is underway (e.g., deltaP/deltaQ is within the predetermined safety margin around the surge line).
[0044] At 330, the first actuator at least partially integrated with the first valve or the first controller actuates the first valve to perform the determined control operation or protection operation for the first turbomachine. For example, the electric actuator 213 can actuate the recycle valve 212 in an
attempt to remedy the surge condition. In some implementations, at least one of the control operation or the protection operation for the first turbomachine can include actuating the first valve to control flow of fluids to an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve. For example, the recycle valve 212 can be actuated to allow compressed gasses to pass through the gas cooler 250 and on to the inlet 206.
[0045] In some embodiments, the process 300 can include providing, by the first controller, controller operations information through a first
communications port, receiving, at a second communications port of a second controller at least partially integrated with a second valve of a second turbomachine or a second actuator configured to actuate the second valve, the controller operations information, and actuating, by the second actuator, the second valve perform at least one of a control operation or a protection operation for the second turbomachine, based at least in part on the received controller operations information. For example, the electric actuator 213 can provide control signals to another electric actuator of another compressor system 200 to cause another recycle valve to be actuated.
[0046] In some embodiments, the process 300 can include providing, by the first controller, controller operations information through a first
communications port, receiving, at a second communications port of a second controller at least partially integrated with a second valve of the first turbomachine or a second actuator configured to actuate the second valve, the controller operations information, and actuating, by the second actuator, the
second valve perform at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received controller operations information. For example, the electric actuator 213 can provide control signals to another electric actuator of the compressor system 200 to cause another recycle valve of the compressor system 200 to be actuated.
[0047] Although a few implementations have been described in detail above, other modifications are possible. For example, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims.
Claims
1. A compressor anti-surge system comprising:
a first actuator configured to actuate a first valve of a first turbomachine; and
a first controller at least partially integrated with the first actuator or the first valve, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine.
2. The compressor anti-surge system of claim 1 , wherein the first actuator is configured to actuate the first valve through a mechanical coupler or a fluid circuit.
3. The compressor anti-surge system of any one of claims 1 or 2, further comprising a first field sensor configured to sense a first turbomachine parameter of the first turbomachine; wherein the first controller is further configured to receive the first turbomachine parameter from the first field sensor and perform at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter.
4. The compressor anti-surge system of any one of claims 1 to 3, wherein the valve is a sliding stem turbomachinery control valve, rotary turbomachinery control valve, or a guide vane.
5. The compressor anti-surge system of any one of claims 1 to 4, further comprising an integral or adjacent heat exchanger in fluid
communication with the valve and configured to cool fluids that are passed through the valve.
6. The compressor anti-surge system of any one of claims 1 to 5,
wherein:
the first controller further comprises a first communication port and is configured to provide controller operations information through the first communications port;
a second actuator configured to actuate a second valve of a second turbomachine; and
a second controller at least partially integrated with the second actuator or the second valve, a second communication port configured to communicate with the first communication port and receive controller operations information, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the second turbomachine, based at least in part on the received controller operations information.
7. The compressor anti-surge system of any one of claims 1 to 6, wherein:
the first controller further comprises a first communication port and is configured to provide controller operations information through the first communications port;
a second actuator configured to actuate a second valve of the first turbomachine; and
a second controller at least partially integrated with the second actuator or the second valve, a second communication port configured to communicate with the first communication port and receive controller operations information, and comprising circuitry configured to perform at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received controller operations information.
8. A method of responding to compressor surge comprising:
receiving, at a first controller at least partially integrated with a first valve and from a first field sensor, a first turbomachine parameter of a first turbomachine;
determining, by the first controller, at least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received first turbomachine parameter; and
actuating, by a first actuator at least partially integrated with the first valve or the first controller, the first valve to perform the determined control operation or protection operation for the first turbomachine.
9. The method of claim 8, wherein the first actuator is configured to
actuate the first valve through a mechanical coupler or a fluid circuit.
10. The method of any one of claims 8 or 9, wherein the valve is a sliding stem turbomachinery control valve, rotary turbomachinery control valve, or a guide vane.
1 1 . The method of any one of claims 8 to 10, wherein at least one of the control operation or the protection operation for the first turbomachine comprises actuating the first valve to control flow of fluids to an integral or adjacent heat exchanger in fluid communication with the valve and configured to cool fluids that are passed through the valve.
12. The method of any one of claims 8 to 1 1 , further comprising:
providing, by the first controller, controller operations information through a first communications port;
receiving, at a second communications port of a second controller at least partially integrated with a second valve of a second turbomachine or a second actuator configured to actuate the second valve, the controller operations information; and
actuating, by the second actuator, the second valve to perform at least one of a control operation or a protection operation for the second turbomachine, based at least in part on the received controller operations information.
13. The method of any one of claims 8 to 12, further comprising:
providing, by the first controller, controller operations information through a first communications port;
receiving, at a second communications port of a second controller at least partially integrated with a second valve of the first turbomachine or a second actuator configured to actuate the second valve, the controller operations information; and
actuating, by the second actuator, the second valve to perform at
least one of a control operation or a protection operation for the first turbomachine, based at least in part on the received controller operations information.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201680064094.6A CN108291553A (en) | 2015-09-02 | 2016-09-01 | Turbomachinery Surge Prevention System |
EP16763700.8A EP3344877A1 (en) | 2015-09-02 | 2016-09-01 | Turbomachine anti-surge system |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/843,486 | 2015-09-02 | ||
US14/843,486 US20170058906A1 (en) | 2015-09-02 | 2015-09-02 | Turbomachine Anti-Surge System |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2017040807A1 true WO2017040807A1 (en) | 2017-03-09 |
Family
ID=56896844
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2016/049939 WO2017040807A1 (en) | 2015-09-02 | 2016-09-01 | Turbomachine anti-surge system |
Country Status (4)
Country | Link |
---|---|
US (1) | US20170058906A1 (en) |
EP (1) | EP3344877A1 (en) |
CN (1) | CN108291553A (en) |
WO (1) | WO2017040807A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114278603B (en) * | 2021-12-27 | 2024-05-14 | 中控技术股份有限公司 | Compressor control system, method, device, equipment and storage medium |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2002451A (en) * | 1977-08-02 | 1979-02-21 | Agar Instr | Control of centrifugal compressors |
CN202431617U (en) * | 2011-12-31 | 2012-09-12 | 杭州哲达科技股份有限公司 | Intelligent anti-surge control valve |
WO2014085095A1 (en) * | 2012-11-28 | 2014-06-05 | Borgwarner Inc. | Compressor stage of a turbocharger with flow amplifier |
WO2014191312A1 (en) * | 2013-05-29 | 2014-12-04 | Siemens Aktiengesellschaft | Method for operating a compressor, and arrangement with a compressor |
US9074606B1 (en) * | 2012-03-02 | 2015-07-07 | Rmoore Controls L.L.C. | Compressor surge control |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3424370A (en) * | 1967-03-13 | 1969-01-28 | Carrier Corp | Gas compression systems |
WO2010075430A1 (en) * | 2008-12-24 | 2010-07-01 | Strands, Inc. | Sporting event image capture, processing and publication |
-
2015
- 2015-09-02 US US14/843,486 patent/US20170058906A1/en not_active Abandoned
-
2016
- 2016-09-01 WO PCT/US2016/049939 patent/WO2017040807A1/en active Application Filing
- 2016-09-01 EP EP16763700.8A patent/EP3344877A1/en not_active Withdrawn
- 2016-09-01 CN CN201680064094.6A patent/CN108291553A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2002451A (en) * | 1977-08-02 | 1979-02-21 | Agar Instr | Control of centrifugal compressors |
CN202431617U (en) * | 2011-12-31 | 2012-09-12 | 杭州哲达科技股份有限公司 | Intelligent anti-surge control valve |
US9074606B1 (en) * | 2012-03-02 | 2015-07-07 | Rmoore Controls L.L.C. | Compressor surge control |
WO2014085095A1 (en) * | 2012-11-28 | 2014-06-05 | Borgwarner Inc. | Compressor stage of a turbocharger with flow amplifier |
WO2014191312A1 (en) * | 2013-05-29 | 2014-12-04 | Siemens Aktiengesellschaft | Method for operating a compressor, and arrangement with a compressor |
Also Published As
Publication number | Publication date |
---|---|
US20170058906A1 (en) | 2017-03-02 |
EP3344877A1 (en) | 2018-07-11 |
CN108291553A (en) | 2018-07-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8567184B2 (en) | Energy recovery system in a gas compression plant | |
US9976565B2 (en) | Compressor surge detection | |
US8278864B2 (en) | Compressor control | |
US20160047392A1 (en) | Methods and systems for controlling turbocompressors | |
EP3567234B1 (en) | Method for controlling an inlet-adjustment mechanism for a turbocharger compressor | |
JP2009047059A (en) | Operating method of motor-driven compressor | |
CN103946555A (en) | Surge prevention during startup of a chiller compressor | |
KR101981877B1 (en) | Method and apparatus for controlling the oil temperature of an oil-injected compressor plant or vacuum pump | |
EP3344877A1 (en) | Turbomachine anti-surge system | |
RU2762473C2 (en) | Method for regulating multistage compressor | |
US9759134B2 (en) | Process for preventing rotating stall and surge in a turbomachine | |
Kurz et al. | Upstream and midstream compression applications: part 2—implications on operation and control of the compression equipment | |
JP2010526961A (en) | Control method of turbo compressor | |
US11933183B2 (en) | Steam turbine valve abnormality monitoring system, steam turbine valve drive device, steam turbine valve device, and steam turbine plant | |
JP2006316759A (en) | Compression device | |
EP3832140B1 (en) | Method for operating a pump, in particular a multiphase pump | |
JP6270838B2 (en) | Engine system and ship | |
KR101760000B1 (en) | Engine system and ship | |
Nored et al. | Development of a guideline for the design of surge control systems | |
Dukle et al. | Validating anti-surge control systems | |
EP2423515A1 (en) | Industrial compressor system | |
CN112219076A (en) | Preventing reverse rotation in a centrifugal compressor | |
JPWO2019186861A1 (en) | Gas compressor | |
WO2022163079A1 (en) | Gas compressor | |
Gülich et al. | Turbine operation, general characteristics |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16763700 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2016763700 Country of ref document: EP |