WO2019003185A1

WO2019003185A1 - System and method for valve diagnosis

Info

Publication number: WO2019003185A1
Application number: PCT/IB2018/054818
Authority: WO
Inventors: Peter Maria LAUER
Original assignee: Eaton Intelligent Power Ltd
Current assignee: Eaton Intelligent Power Ltd
Priority date: 2017-06-29
Filing date: 2018-06-28
Publication date: 2019-01-03
Anticipated expiration: 2019-12-29

Abstract

L'invention concerne un système et un procédé permettant de déterminer un état d'usure d'un ensemble formant une soupape. L'ensemble formant une soupape (10) comprend un ensemble formant un boîtier (202) de soupape, un corps (206) de soupape, définissant un alésage (212) de soupape, et une bobine (210), mobile à l'intérieur de l'alésage de soupape, au moins un capteur (22, 28, 30) et un dispositif de commande (14), configuré pour collecter et pour stocker des données de capteur, accumulées à partir dudit capteur pour déterminer l'état d'usure de l'ensemble formant une soupape. Les données de capteur accumulées sont utilisées pour déterminer l'état d'usure de l'ensemble formant une soupape.A system and method for determining a wear state of a valve assembly. The valve assembly (10) comprises a valve housing assembly (202), a valve body (206) defining a valve bore (212), and a coil (210) movable therein of the valve bore, at least one sensor (22, 28, 30) and a controller (14) configured to collect and store sensor data accumulated from said sensor to determine the state of wear of the valve assembly. The accumulated sensor data is used to determine the wear state of the valve assembly.

Description

SYSTEM AND METHOD FOR VALVE DIAGNOSIS

Introduction

Various industrial applications use hydraulic components/systems for actuating various components within those applications. Such hydraulic components can include various pumps, motors, cylinders, valves, and sensors.

Summary

The present disclosure relates generally to a method and system for valve diagnosis.

In one aspect, the present description relates to a method for determining a wear status of a valve assembly, comprising: collecting sensor data; generating accumulated sensor data; and determining the wear status of the valve assembly based on the accumulated sensor data; wherein the accumulated sensor data is selected from the group consisting of an accumulated linear distance, an accumulated number of startup cycles, an accumulated number of operation hours, an accumulated number of operation hours weighted by temperature, and an accumulated number of operation hours weighted by supply voltage.

In another aspect, the present disclosure relates to a system for determining a wear status of a valve assembly, comprising: at least one sensor embedded in a valve assembly, a controller configured to collect data from the at least one sensor for generating an accumulated sensor data; wherein the wear status of the valve assembly is determined by an algorithm that uses the accumulated sensor data; wherein the accumulated sensor data is selected from the group consisting of an accumulated linear distance, an accumulated number of startup cycles, an accumulated number of operation hours, an accumulated number of operation hours weighted by temperature, and an accumulated number of operation hours weighted by supply voltage.

In yet another aspect, the present disclosure relates to a valve assembly, comprising: a valve housing assembly having a valve body defining a valve bore and a spool configured to move within the valve bore; at least one sensor; and a microcontroller configured to collect data from the at least one sensor for generating an accumulated sensor data; wherein the wear status of the valve assembly is determined by an algorithm that uses the accumulated sensor data; wherein the accumulated sensor data is selected from the group consisting of an accumulated linear distance, an accumulated number of startup cycles, an accumulated number of operation hours, an accumulated number of operation hours weighted by temperature, and an accumulated number of operation hours weighted by supply voltage.

A variety of additional aspects will be set forth in the description that follows. The aspects can relate to individual features and to combination of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based.

Brief Description of the Drawings

FIG. 1 is an isometric view of a valve assembly having exemplary features of aspects in accordance with the principles of the present disclosure.

FIG. 2 is a cross-sectional view of the valve assembly of FIG. 1.

FIG. 3 is an exemplary circuit diagram for a controller of the valve assembly of FIG. 1. FIG. 4 is a block diagram illustrating a system for determining a wear status of the valve assembly of FIG. 1.

FIG. 5 is block diagram illustrating an algorithm for determining a wear status of the valve assembly of FIG. 1.

FIG. 6 is an example method for storing accumulated sensor data in a memory of a controller in the valve assembly of FIG. 1.

FIG. 7 is a flow chart illustrating a method for determining a wear status of the valve assembly of FIG. 1.

Detailed Description

Various embodiments will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims.

FIG. 1 is an isometric view of a valve assembly 10. The valve assembly 10 includes an electronics housing 204 connected to a valve housing assembly 202. The valve housing assembly 202 includes a valve body 206. In the example depicted in FIG. 1 , the valve body 206 includes a manifold mounting surface 208 that is adapted to serve as a mounting location for a fluid device (e.g., manifold block, pump, motor, steering unit, cylinder, etc.).

FIG. 2 is a cross-sectional view of the valve assembly 10. The valve body 206 includes a spool 210 disposed in a bore 212. Solenoids 214, 216 are located on either side of the spool 210. Solenoids 214, 216 actuate the spool 210 in left and right directions for controlling the flow of fluid from the fluid device when engaged with the manifold mounting surface 208. The valve housing assembly 202 includes a linear displacement sensor 22 located next to the solenoid 214 for measuring the linear distance that the spool 210 travels in the bore 212.

As shown in FIG. 2, the electronics housing 204 includes a controller 14 and a connector 220. The controller 14 includes a temperature sensor 28 and a voltage sensor 30. The connector 220 supplies power to the valve assembly 10, and also provides a connection for receiving commands for operating the valve assembly 10.

FIG. 3 is a schematic of an exemplary circuit 11 in the valve assembly 10. As described above, power is supplied from the connector 220 and valve commands are received from the connector 220. The supplied power is conditioned by a converter 222 to have the correct voltage before reaching the controller 14. In some example embodiments, the converter 222 is an AC -DC converter or a DC-DC converter. The valve commands are received by an input circuit 223 which relays the valve commands to the controller 14. The controller 14 processes and sends the valve commands to an output circuit 225 which is configured to actuate the solenoids 214, 216 for moving the spool 210 in the bore 212 of the valve body 206. The linear displacement sensor 22 measures the distance that the spool 210 travels in the bore 212 and sends this information to a feedback circuit 227 which is configured to relay this information to the controller 14 for storage.

FIG. 4 shows an example system 100 for determining a wear status of the valve assembly 10. The example system 100 includes onboard valve electronics 12, the controller 14, a communication module 16, and cloud and web-based services 18.

The onboard valve electronics 12 includes the various sensors disposed in the valve assembly 10. For example, the onboard valve electronics 12 includes the linear displacement sensor 22, the temperature sensor 28, and the voltage sensor 30, and can also include a power cycle sensor 24, an operating hour counter 26, and a cycle counter 32. The controller 14 is configured to both operate the valve assembly 10 while also providing diagnostic functionality such as determining the wear status of the valve assembly 10. As used herein, the term "controller" means a microcontroller or any variant thereof that contains one or more processors, memories, and programmable input/output modules.

The controller 14 collects and stores data from the various sensors of the onboard valve electronics 12. The data stored in the controller 14 is continually updated during pre-set time intervals so that accumulated data values can be monitored for determining the wear status of the valve assembly 10. For example, the controller 14 can include a first storage module 34 for storing an accumulated linear displacement 104 or an accumulated number of valve cycles 106, a second storage module 36 for storing an accumulated number of startup cycles 108, a third storage module 38 for storing an accumulated number of operating hours 110, a fourth storage module 40 for storing an accumulated number of operation hours weighted by valve temperature 112, and a fifth storage module 42 for storing an accumulated number of operation hours weighted by supply voltage 114. In this way, data from the sensors in the onboard valve electronics 12 is stored and accumulated in the controller 14. In one example, the controller 14 is configured to process the accumulated sensor data to perform diagnostic and prognostic analyses of the valve assembly 10.

In another alternative example, the controller 14 is configured to send the accumulated sensor data to cloud and web-based services 18 so that the accumulated sensor data can be processed by an external device 20 separate from the valve assembly 10.

The communication module 16 is configured to transfer the accumulated sensor data from the controller 14 to higher level systems such as the cloud and web-based services 18. Internet of Things (IOT) connectivity in the form of communication networks such as Wi-Fi, Bluetooth, CANbus, and Ethernet can be used by the communication module 16 to transfer the accumulated sensor data to the cloud and web-based services 18. Computing and processing for IOT protocols such as web servers, OPCOE, TCP/IP, UDP, and other IOT web interfaces can be performed for the secure transfer of data from the controller 14 to the cloud and web-based services 18.

The cloud and web-based services 18 can be accessed via an external device 20 which is separate from the valve assembly 10. Accordingly, the cloud and web-based services 18 can be accessed by various parties or entities for further analysis and evaluation of the accumulated sensor data. For example, the cloud and web-based services 18 can be accessed by the engineering, warranty, sales, and manufacturing departments of the valve assembly manufacturer, or can be accessed by an end user or customer, or any kind of distributor or service organization.

FIG. 5 is a block diagram illustrating an algorithm 500 for determining a wear status 102 of the valve assembly 10. As shown in FIG. 5, the accumulated sensor data is used by an algorithm 500 for determining the wear status 102 of the valve assembly 10. For example, an accumulated linear displacement 104, an accumulated number of valve cycles 106, an accumulated number of startup cycles 108 (i.e., the number of times the valve assembly has been powered from an inactive state to an active state), an accumulated number of operating hours 110, an accumulated number of operating hours weighted by valve temperature 112, and an accumulated number of operating hours weighted by supply voltage 114 can be used by algorithm 500, either individually or in combination, for determining the wear status 102 of the valve assembly 10.

With respect to the accumulated operating hours weighted by valve temperature 112, the controller 14 can detect temperatures exceeding a maximum temperature value via the temperature sensor 28. The controller 14 can also record an accumulated time that the valve assembly 10 operates at temperatures exceeding the maximum temperature value via the operating hour counter 26. Algorithms based on accelerated life testing can be used to quantify the increase in wear on the valve assembly 10 that results from operating at temperatures above the maximum temperature value. Accordingly, the accumulated operating hours weighted by valve temperature 112 takes into account the increase in wear that results from the valve assembly 10 operating at elevated temperatures, and this data can be used, either individually or in combination with other accumulated sensor data, for determining the wear status 102 of the valve assembly 10.

With respect to the accumulated operating hours weighted by supply voltage 114, a valve assembly is typically operated under a supply voltage of 24V, however, in some applications, or under some circumstances, a valve assembly could be run at a higher supply voltage which can increase the wear on the valve assembly. In one example, the controller 14 can detect supply voltages exceeding a maximum supply voltage value via the voltage sensor 30, and the controller 14 can also record the accumulated time that the valve assembly 10 operates at supply voltages exceeding the maximum supply voltage value via the operating hour counter 26. Algorithms based on accelerated life testing can be used to quantify the increase in wear on the valve assembly 10 that results from operating under higher supply voltages. Accordingly, the accumulated operating hours weighted by supply voltage 114 takes into account the increase in wear that results from the valve assembly 10 operating at elevated supply voltages, and this data can be used, either individually or in combination with other accumulated sensor data, for determining the wear status 102 of the valve assembly 10.

In one example, the accumulated linear displacement 104 of the spool 210 is used for determining the wear status 102 of the valve assembly 10. The linear displacement sensor 22 measures the distance the spool 210 travels in the bore 212 during a pre-set time interval. The linear displacement sensor 22 can be a linear variable differential transformer (LVDT) for measuring the accumulated linear displacement 104 of the spool 210. At the end of each pre-set time interval, the controller 14 is configured to add a recorded distance to an accumulated linear displacement 104 stored in the first storage module 34 of the controller 14. In one particular example, the pre-set time interval is every two minutes. In other examples, the pre-set time interval can be longer or shorter than 2 minutes. By continually updating the accumulated linear displacement 104 and comparing the accumulated linear displacement 104 to the life expectancy of the valve assembly 10, the wear status 102 of the valve assembly 10 can be determined.

As an example for purposes of explanation, an exemplary valve assembly can have a life expectancy of 10 million cycles, and each cycle in the exemplary valve assembly can comprise a +/-2mm spool movement. Accordingly, the exemplary valve assembly would have a life expectancy of 800,000 meters of total linear displacement.

In an alternative example, a cycle counter 32 records the number of cycles of the spool 210 during a pre-set time interval. At the end of each pre-set time interval, the controller 14 is configured to add the recorded cycles to the accumulated number of valve cycles 106 stored in the first storage module 34 of the controller 14. In one particular example, the pre-set time interval is every two minutes. In other examples, the pre-set time interval can be longer or shorter than 2 minutes. By continually updating the accumulated number of valve cycles 106 and comparing the accumulated number of valve cycles 106 to the life expectancy of the valve assembly 10, the wear status 102 of the valve assembly 10 can be determined.

Additional sensor data can be used to supplement the accumulated linear displacement 104 of the spool 210 or the accumulated number of valve cycles 106 of the spool 210. For example, sensor data such as the accumulated number startup cycles 108, the accumulated number of operating hours 110, the accumulated number of operation hours weighted by valve temperature 112, and the accumulated number of operation hours weighted by supply voltage 114 can also be used for determining the wear status 102 of the valve assembly 10. Each type of accumulated sensor data can be used to supplement another type of accumulated sensor data or can be used individually for determining the wear status 102 of the valve assembly 10. Accordingly, each type of accumulated sensor data can be used either individually or in combination for determining the wear status 102 of the valve assembly 10.

The controller 14 is an improved microcontroller that has been modified to have increased storage and faster processing speeds, while also being small in size so that it can fit within the electronics housing 204 of the valve assembly 10. The controller 14 includes Electrically Erasable Programmable Read-Only Memory (EEPROM) cells which are a type of non-volatile memory that can store data while allowing individual bytes to be erased and reprogrammed. EEPROMs do not require a separate chip, and are thus compact and cost effective. However, standard EEPROMs have a limited life for erasing and reprogramming, and this is a significant drawback for the controller 14 which stores, updates, and processes large amounts of data.

In order to overcome the physical constraints of EEPROMs, the controller 14 stores the sensor data in (8,4) Gray code over several EEPROM memory cells. Storing the accumulated sensor data in (8,4) Gray code increases the life of a standard EEPROM memory cell, and accordingly, allows the controller 14 to store more data and to process data at faster speeds. Another benefit of storing the accumulated sensor data in (8,4) Gray code is that the accumulated sensor data is encoded such that the accumulated sensor data can only be accessed by authorized personnel. Thus, an added level of security can be added to the valve assembly 10 so that the accumulated sensor data cannot be used by third-parties. As an alternative to EEPROM memory cells, FRAM, Flash, or battery backed RAM can be used to store the accumulated sensor data.

FIG. 6 illustrates a method 600 for storing the accumulated sensor data in a memory of the controller 14. The method 600 starts by performing a first step 602 of reading the address of a first memory cell. Next, the method 600 includes a step 604 of reading the contents of the EEPROM location based on the address of the first memory cell that was read in the first step 602.

Thereafter, a step 606 determines whether a value of the first memory cell matches a stored value. When the value of the first memory cell matches the stored value, the method 600 includes step 608 of incrementing the first memory cell by a measured value to produce an incremented value, and storing the incremented value into the EEPROM memory. Thereafter, the method 600 ends. The measured value is measured by one or more of the various sensors disposed in the valve assembly 10 (e.g., the linear displacement sensor 22, the temperature sensor 28, the voltage sensor 30, the power cycle sensor 24, the operating hour counter 26, and the cycle counter 32).

When the value of the first memory cell does not match the stored value, the method 600 includes step 610 of reading the address of a second memory cell and reading the contents of the EEPROM location based on the address of the second memory cell. Thereafter, a step 612 determines whether a value of the second memory cell matches the stored value.

When the value of the second memory cell matches the stored value, the method 600 includes step 614 of incrementing the second memory cell by the measured value to produce the incremented value, and storing the incremented value into the EEPROM memory. Thereafter, the method 600 ends. When the value of the second memory cell does not match the stored value, the method 600 includes step 616 of reading the address of a third memory cell and reading the contents of the EEPROM location based on the address of the third memory cell.

Thereafter, the method 600 includes a step 618 of incrementing the address of the first memory cell and clearing its contents, and incrementing the address of the second memory cell and clearing its contents. Next, the method 600 includes a step 620 incrementing the third memory cell by the measured value to produce the incremented value, and storing the incremented value into the EEPROM memory. The method 600 may repeat the steps 602-620 as may be needed. Thereafter, the method 600 ends.

FIG. 7 is a flow chart illustrating a method 700 for determining the wear status 102 of the valve assembly 10. The method 700 includes collecting 702 sensor data from various sensors disposed in the valve assembly 10 and storing 704 the collected sensor data in one or more memories. The sensor data is collected and stored during pre-set time intervals such that the sensor data is stored as an accumulated value. In certain examples, the sensor data is stored in step 704 according to the method 600 illustrated in FIG. 6. In one example, the pre-set time interval is 2 minutes. In other examples, the pre-set time interval can be more than or less than 2 minutes. In this way, the sensor data is continually collected and stored. The method 700 further includes processing 706 the accumulated sensor data. In step 706, the algorithm 500 (shown in FIG. 5) is used for determining the wear status 102 of the valve assembly 10. The algorithm 500 can use several different types of accumulated sensor data for determining the wear status 102 of the valve assembly 10. For example, an accumulated linear displacement 104 of the valve spool, an accumulated number of valve cycles 106, an accumulated number of startup cycles 108, an accumulated number of operating hours 110, an accumulated number of operation hours weighted by valve temperature 112, and an accumulated number of operation hours weighted by supply voltage 114 can be used by algorithm 500, either separately or in combination, for determining the wear status 102 of the valve assembly 10.

The method 700 differs from known diagnostic methods because the algorithm 500 uses accumulated sensor data for determining the wear status 102. For example, known valve diagnostic methods typically use the operating conditions of a valve assembly, such as whether the valve assembly is operating at an abnormal pressure or temperature, for determining the approximate wear status 102 of the valve assembly. Typically, such diagnostics are performed after a customer has already complained about the valve not working properly, and hence, toward the end of the valve assembly's life. In contrast, the method 700 and algorithm 500 use accumulated sensor values for determining the wear status 102 of the valve assembly 10 in real-time. Thus, the method 700 and algorithm 500 are not dependent on the operating characteristics of a valve assembly during a particular point in time, but rather take into consideration the accumulated history of the operation of the valve assembly 10. Accordingly, the method 700 can determine the wear status 102 of the valve assembly 10 at an earlier stage (e.g., before a valve malfunction).

The method 700 includes an optional fourth step 708 of transferring the accumulated sensor data from the valve assembly 10 to the cloud and web-based services 18 for access by the external device 20. Step 708 is optional because in some embodiments, the algorithm 500 can be performed by the controller 14 on the valve assembly 10 such that diagnostic data can be presented directly on the valve assembly 10. In alternative embodiments, the algorithm 500 can be performed by the external device 20, or the accumulated sensor data can be transferred to the external device 20 for further analysis and evaluation. Internet of Things (IOT) connectivity in the form of communication networks such as Wi-Fi, Bluetooth, CAN bus, and Ethernet can be used to transfer the accumulated sensor data to the cloud and web-based services 18. In addition, computing and processing for IOT protocols, such as web servers, OPCOE, TCP/IP, UDP, and other IOT web interfaces can be performed. Optionally, the accumulated sensor data can be encoded in (8,4) Gray code before it is transferred to the cloud and web-based services 18 so that the accumulated sensor data can only be accessed by authorized personnel.

The cloud and web-based services 18 can be accessed via the external device 20 by various parties or entities for further analysis and evaluation of the accumulated sensor data. For example, the cloud and web-based services 18 can be accessed by the engineering, warranty, sales, and manufacturing departments of the valve assembly manufacturer, or can be accessed by an end user or customer, or any kind of distributor or service organization for further analysis and evaluation of the accumulated sensor data.

The valve assembly 10 can be any type of valve assembly. In one specific and non-limiting example, the valve assembly 10 is a hydraulic proportional valve which can be used in various types of industries and applications. For example, hydraulic proportional valves can be used in wind turbines, injection mold machines, oil and gas platforms, and theater equipment such as the rigging for curtains and drapery.

In the specific case of wind turbines, areas that experience frequent changes in wind direction and velocity require wind turbines to constantly adjust the pitch of their blades in order to regulate the rotation speed and power generation of the wind turbine. Accordingly, hydraulic proportional valves used in wind turbines located in these areas will have higher work rates and shorter life spans. In this type of scenario, the system 100 and method 700 for determining the wear status 102 of the valve assembly 10 would be particularly advantageous because they would allow the operator of the wind turbine to know the wear status 102 of the valve assembly 10 before it breaks down. Thus, the wind turbine operator could order a replacement valve assembly before an installed valve assembly breaks down. This will reduce the downtime of the wind turbine, and hence, increase the energy production of the wind turbine.

The various embodiments described above are provided by way of illustration only and should not be construed to limit the claims attached hereto. Those skilled in the art will readily recognize various modifications and changes that may be made without following the example embodiments and application illustrated and described herein, and without departing from the true spirit and scope of the following claims.

Claims

We claim:

1. A method for determining a wear status of a valve assembly, comprising:

collecting sensor data;

generating accumulated sensor data; and

determining the wear status of the valve assembly based on the accumulated sensor data; wherein the accumulated sensor data is selected from the group consisting of an accumulated linear distance, an accumulated number of startup cycles, an accumulated number of operation hours, an accumulated number of operation hours weighted by temperature, and an accumulated number of operation hours weighted by supply voltage.

2. The method of claim 1, wherein the accumulated sensor data is generated and stored in a controller housed in the valve assembly.

3. The method of claim 1, wherein the accumulated sensor data is stored as Gray code in one or more EEPROM memory cells disposed in a controller.

4. The method of claim 1, wherein the accumulated sensor data is transferred to a cloud or web-based service.

5. The method of claim 1, wherein the accumulated sensor data is encoded in Gray code before being transferred to a cloud or web-based service.

6. A system for determining a wear status of a valve assembly, comprising:

at least one sensor embedded in a valve assembly; and

a controller configured to collect data from the at least one sensor for generating an accumulated sensor data, the wear status of the valve assembly is determined by an algorithm that uses the accumulated sensor data, and wherein the accumulated sensor data is selected from the group consisting of an accumulated linear distance, an accumulated number of startup cycles, an accumulated number of operation hours, an accumulated number of operation hours weighted by temperature, and an accumulated number of operation hours weighted by supply voltage.

7. The system of claim 6, wherein the controller is configured to store the accumulated sensor data as Gray code in one or more EEPROM memory cells.

8. The system of claim 6, wherein the at least one sensor is selected from the group consisting of a linear displacement sensor, a power cycle sensor, an operating hour counter, a temperature sensor, and a voltage sensor.

9. The system of claim 8, wherein the linear displacement measures the distance traveled by a spool disposed in a bore of the valve assembly.

10. The system of claim 8, wherein the temperature and voltage sensors are housed in the controller.

11. The system of claim 6, wherein the controller is configured to transfer the accumulated sensor data to a cloud or web-based service.

12. A valve assembly, comprising:

a valve housing assembly having a valve body defining a valve bore and a spool configured to move within the valve bore;

at least one sensor inside or adjacent to the valve housing assembly; and

a microcontroller configured to collect data from the at least one sensor for generating an accumulated sensor data;

wherein a wear status of the valve assembly is determined by an algorithm that uses the accumulated sensor data, the accumulated sensor data being selected from the group consisting of an accumulated linear distance, an accumulated number of startup cycles, an accumulated number of operation hours, an accumulated number of operation hours weighted by temperature, and an accumulated number of operation hours weighted by supply voltage.

13. The valve assembly of claim 12, wherein the at least one sensor is selected from the group consisting of a linear displacement sensor, a power cycle sensor, an operating hour counter, a temperature sensor, and a voltage sensor.

14. The valve assembly of claim 12, wherein the controller comprises one or more EEPROM memory cells configured for storing the accumulated sensor data in Gray code.

15. The valve assembly of claim 12, wherein the at least one sensor is a linear displacement configured to measure the distance traveled by a spool disposed in a bore of the valve assembly.

16. The valve assembly of claim 12, wherein the at least one sensor comprises a temperature sensor and a voltage sensor housed in the controller.