WO2019104969A1

WO2019104969A1 - Fault diagnosis method and device for main distributing valve of hydraulic turbine governor, and storage medium

Info

Publication number: WO2019104969A1
Application number: PCT/CN2018/088500
Authority: WO
Inventors: 张雷; 蔡卫江; 孙延岭; 何林波; 荣红
Original assignee: 国电南瑞科技股份有限公司; 南瑞集团有限公司
Priority date: 2017-11-28
Filing date: 2018-05-25
Publication date: 2019-06-06
Also published as: CN107991077A; CN107991077B

Abstract

A fault diagnosis method for a main distributing valve of a hydraulic turbine governor, a fault diagnosis device and a computer storage medium, said fault diagnosis method comprising: acquiring a proportional servo valve feedback signal, a main distributing valve position feedback signal and a servomotor travel feedback signal; and determining, according to the proportional servo valve feedback signal, the main distributing valve position feedback signal and the servomotor travel feedback signal, whether the main distributing valve of the hydraulic turbine governor fails and/or the type of the failure. Said method achieves accurate and timely determination, has a comprehensive basis for determination, and can accurately determine location of a failure and give a corresponding maintenance decision.

Description

Hydraulic turbine governor main pressure regulating valve fault diagnosis method and device, storage medium

Cross-reference to related applications

The present application is based on a Chinese patent application filed on Jan. 28, 2017, the entire disclosure of which is hereby incorporated by reference.

Technical field

The invention relates to the technical field of control of a main pressure regulating valve of a water turbine governor, in particular to a fault diagnosis method and device for a main pressure regulating valve of a water turbine governor, and a computer storage medium.

Background technique

The turbine governor is an important equipment for hydropower plants, and it is responsible for regulating the speed of the turbine and controlling the output. The main pressure regulating valve is one of its most important actuators. The turbine governor converts the electrical signal into the direction of the oil pressure and the flow rate signal through the electrohydraulic proportional proportional servo valve. The signal is amplified by the main pressure regulating valve to operate the vane servo. In the middle of the actual use process, the main pressure regulating valve is easily jammed due to problems such as oil viscosity, impurity particles, and wear. The quality of the main pressure regulating valve directly affects the adjustment quality and safety and stability of the unit. Therefore, it is particularly important that the governor can accurately and quickly diagnose the working state of the main pressure regulating valve.

In recent years, the fault diagnosis technology of hydroelectric generating sets has been widely used in hydropower plants, but the systems that have been applied currently do not include the monitoring of turbine governing equipment. The speed regulating equipment is an important equipment for controlling the speed and power of hydroelectric generating sets. The quality and performance of the adjustment are directly related to the stable operation of the unit.

At present, the common main function of the refusal of the hydropower plant is judged, and the main function is to reject the action. It is the only monitoring function to judge the failure of the main pressure regulating valve. By installing the main matching stroke position contact on the main assembly, the method of judging the main operation failure is judged by judging the judgment condition of the first electric overspeed fault and the main matching in the unclosed direction. The specific judgment logic is to judge that the main match is in the opening direction and the unit frequency is greater than the first-level electrical over-speed and then delay for a period of time, that is, the main match is rejected. Only the condition that the main card is blocked in the opening direction can be judged, and since the installation position and the debugging gap of the position switch are not the same, the sensitivity of determining the fault is different, and the judgment conclusion is difficult to be satisfactory. It is too sloppy to judge whether the over-speed shutdown should be performed by a simple position switch, and the triggering conditions are harsh, and the delay time is long. When the fault is reported, the fault has been expanded. And the main matching position contact does not have good installation conditions, the fault triggering accuracy is greatly affected by the level of the construction personnel, and the actual reported signal is not reliable. In most cases, it is not trusted by the engineering personnel, so the fault judgment is ineffective. The actual use effect is not ideal.

Summary of the invention

The embodiment of the invention is expected to provide a fault diagnosis method and device for a main pressure regulating valve of a water turbine governor, and a storage medium, which solves the problem that the main pressure regulating valve cannot be fully diagnosed and/or accurately judged.

The invention provides a fault diagnosis method for a main pressure regulating valve of a water turbine governor, which comprises:

The proportional servo valve feedback signal, the main pressure regulating valve position feedback signal and the servomotor stroke feedback signal are collected to judge the main matching refusal fault;

The feedback rate change rate of the servo valve is collected, the rate of change of the feedback of the main pressure regulating valve, and the rate of change of the feedback of the servomotor are performed to judge the fault of the main matching motion;

The proportional servo valve feedback signal, the main pressure regulating valve position feedback signal and the servomotor stroke feedback signal are collected to judge the main valve spool stuck fault.

In the embodiment of the present invention, a method for comprehensively judging a proportional servo valve feedback signal, a main matching feedback signal, a main matching position contact signal, and a relay stroke feedback signal to perform fault diagnosis on a main pressure regulating valve of a core component of a water turbine governor, It replaces the current main valve of the turbine governor with only one position contact switch and working condition to judge the main fault. The method is accurate and timely, and the judgment is comprehensive. It can accurately determine the fault location and propose corresponding maintenance decisions. It overcomes the shortcomings such as the unreliable judgment of the existing position joint judgment method and the difficulty in installing the contact switch. And the fault diagnosis program can be run inside the governor, and the fault diagnosis and prediction of the governor main pressure regulating valve can be performed by obtaining the operating state of the governor itself in real time. The method does not need external special monitoring device, and the governor device can realize the fault diagnosis of the governor main pressure regulating valve by itself, and has the advantages of low cost, strong portability, flexible configuration, and saving system resources. , can generally improve the ability of the main governor valve of the turbine governor to determine the fault. The fault diagnosis method using this main fault diagnosis method can replace the traditional method in the past and has a great promotion significance.

DRAWINGS

1 is a schematic diagram of a fault diagnosis loop signal of a governor main pressure regulating valve provided by an embodiment of the present invention;

2 is a schematic diagram of a logic flow of determining a main failure rejection fault according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a logic flow for determining a fault of a main matching motion failure according to an embodiment of the present invention; FIG.

4 is a schematic diagram of a logic flow determination process of a main valve spool stuck fault according to an embodiment of the present invention;

FIG. 5 is a schematic flowchart of fault diagnosis of a main pressure regulating valve of a governor according to an embodiment of the present invention.

Detailed ways

The invention is further described below in conjunction with the drawings. The following examples are only intended to more clearly illustrate the technical solutions of the present invention, and are not intended to limit the scope of the present invention.

The main pressure regulating valve is a power stage hydraulic amplifier of the hydraulic governor of the turbine governor. It can be used to amplify the mechanical displacement or hydraulic control signal of the electro-hydraulic converter into a correspondingly proportional hydraulic pressure that meets the requirements of the servomotor flow. Signal to control the opening or closing of the servo. The main pressure regulating valve pushes the relay to push the turbine inlet guide vanes to control the turbine inlet flow rate, thereby achieving the purpose of controlling the turbine speed.

The main pressure regulating valve control circuit of the governor is: the governor controller sends the proportional servo valve control signal to the proportional servo valve, the proportional servo valve output control signal drives the main pressure regulating valve, and the main pressure regulating valve operates the relay valve to Implement control functions. In the middle of the actual use process, the main pressure regulating valve is prone to malfunction due to oil viscosity, impurity particles, wear and the like.

There is a close relationship between the input and output of the main pressure regulating valve. The input and output voltage signals have the same volts and the same direction, and the feedback signal lags slightly behind the control output. At the same time, the servomotor feedback signal is monitored. Through the trend analysis of the servomotor feedback signal, it can be judged that the servomotor has three motion states of opening, closing and stopping, which is used as the judgment condition for the fault state analysis of the main pressure regulating valve.

The fault diagnosis loop signal of the governor main pressure valve can be shown in Figure 1. The main pressure valve fault diagnosis can comprehensively judge the proportional servo valve feedback signal, the main pressure valve position feedback signal and the servo stroke feedback signal. The logical relationship between the feedbacks is a judgment condition. If the relationship between the signals deviates from the above principle, an alarm can be output to remind the power plant maintenance personnel to perform fault processing.

As shown in FIG. 5, a method for troubleshooting a main pressure regulating valve of a water turbine governor according to an embodiment of the present invention includes the following steps:

Step S101: collecting a proportional servo valve feedback signal, a main pressure regulating valve position feedback signal, and a servomotor stroke feedback signal;

Step S102: Determine whether the main pressure regulating valve is faulty and/or fault type according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal.

For example, determining whether the main pressure regulating valve is faulty and/or fault type according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the signal value of the servomotor stroke feedback signal;

For another example, determining whether the main pressure regulating valve is faulty and/or fault type according to a change direction of the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the signal value of the servomotor stroke feedback signal;

For another example, based on the rate of change of the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the signal value of the servomotor stroke feedback signal, it is determined whether the main pressure regulating valve is faulty and/or fault type.

For example, in some embodiments, the hydro-turbine governor main pressure valve fault diagnosis method may include:

The proportional servo valve feedback signal, the main pressure regulating valve position feedback signal and the servomotor stroke feedback signal are collected to judge the main matching refusal fault.

The main matching refusal means that the main pressure regulating valve (referred to as the main matching valve) stops at the neutral position and cannot be normally switched. The main control failure logic determination flow chart is shown in FIG. 2, and the determination method includes: when the signal value of the proportional servo valve feedback signal is the first value, (for example, the first value may be non-zero, for example, greater than The other signal value close to zero), that is, the input pressure of the main pressure regulating valve has a tendency to open or close, and the signal value of the feedback signal of the main pressure regulating valve has a second value (for example, the second take The value can be zero or other value close to zero. The motion of the servomotor is zero in the non-fully open and non-fully closed state, and the delay is for a period of time (the delay time is at the set first delay threshold). Within the range), it is judged that the main failure is rejected. This signal can be used as a judgment condition for the accident shutdown in the running state of the unit. The servomotor is in a non-fully open and non-fully closed state: the servomotor is in a state where a part of the switch is closed and a part of the switch is disconnected.

In other embodiments, the method for troubleshooting a main pressure regulating valve of a water turbine governor may include:

The feedback servo valve feedback change rate, the main pressure valve feedback change rate and the servo relay feedback change rate are collected, and the main matching motion is poor. Here, the rate change rate of the proportional servo valve is: the rate of change of the feedback signal of the proportional servo valve; the rate of change of the feedback of the main pressure valve is: the rate of change of the feedback signal of the main pressure valve; the feedback change of the servo The rate is the rate of change of the servo feedback signal.

Poor main movement is the main valve spool can follow the proportional servo valve, but the movement is not smooth, there is a large lag. The judging method includes: when the proportional servo valve feedback change rate is normal, and the feedback rate of the main pressure regulating valve is slow, the servo relay feedback rate is slow, and the delay is for a period of time (for example, the delay time is in the range of the second delay threshold) Inside), it is judged that the main coordination movement is not smooth, and the main control movement is not smooth. The signal report can be used as a judgment condition for the maintenance alarm in the running state of the unit. The main movement is not smooth because the main valve spool is worn or dirty, and the movement resistance is large. It is found that the fault can be detected in advance and the power plant operators can be dealt with in advance to prevent serious faults.

The proportional servo valve feedback change rate is normal: the proportional servo valve feedback change rate is within a preset first range, and the first range is a range in which the proportional servo valve feedback change rate is normal. The rate of change of the feedback pressure of the main pressure regulating valve comprises: the rate of change of the feedback of the main pressure regulating valve is within a preset second range, indicating that the rate of change of the feedback of the main pressure regulating valve is less than a preset normal range, which is a relatively slow range. . The slow rate of feedback change of the servomotor includes: the speed of the servo feedback feedback is within a preset third range, for example, the servo feedback feedback rate is less than a preset normal range, that is, within a slowly varying range.

In some embodiments, the fault diagnosis method for the main pressure regulating valve of the water turbine governor may include: collecting a proportional servo valve feedback signal, a main pressure regulating valve feedback signal, and a servomotor feedback signal to perform a main valve spool card. Live fault judgment.

The main valve spool is stuck. The main valve plug is stuck in the opening direction or the closing direction. It is not controlled by the proportional servo valve, and the guide vanes are fully open or fully closed. The flow chart of the main valve spool stuck fault logic is shown in Figure 4. The judgment method is that when the direction of the feedback signal of the proportional servo valve is opposite to the direction of the feedback signal of the main pressure valve, the motion of the feedback signal of the main pressure valve The trend is stopped and not in the neutral position (ie, the main pressure valve feedback signal is maintained at the signal value position outside the neutral position), and the servo feedback signal indicates that the servo is in the fully open or fully closed position and is delayed for a period of time (eg, When the time is within the range of the preset third delay threshold, it is determined that the main valve spool stuck fault, and the signal report can be used as a judgment condition for the accident stop in the running state of the unit. The main valve spool is stuck because the main valve spool is affected by the dirty oil quality, and it is stuck in the open position or the closed position. At this time, the guide vanes are fully open or fully closed. Reporting this fault can reduce the accident in advance. loss.

In this embodiment, the direction of the signal is related to the positive and negative values of the signal value. For example, the signal value of the proportional servo valve feedback signal is positive, and the signal value of the main pressure regulating valve feedback signal is negative, then the proportional servo valve feedback signal The direction is opposite to the direction of the feedback signal of the main pressure regulating valve; for example, the signal value of the proportional servo valve feedback signal is negative, and the signal value of the feedback signal of the main pressure regulating valve is positive, then the direction of the proportional servo valve feedback signal is the same as the main The pressure feedback valve feedback signal is in the opposite direction.

In this embodiment, the first delay threshold, the second delay threshold, and the third delay threshold may be equal or may not be equal.

The embodiment of the invention provides a method for comprehensively judging the proportional servo valve feedback, the main matching feedback, the main matching position contact, the relay stroke feedback and the like, thereby performing fault diagnosis on the main pressure regulating valve of the core component of the water turbine governor, At present, the main pressure regulating valve of the turbine governor uses only one position contact switch and working condition to judge the main fault. The method is accurate and timely, and the judgment is comprehensive. The fault location can be accurately determined and the corresponding maintenance decision can be made, which overcomes the shortcomings such as the unreliable judgment of the existing position joint judgment method and the difficulty in installing the contact switch. And the fault diagnosis method can be run inside the governor, and the fault diagnosis and prediction of the governor main pressure regulating valve can be performed by real-time obtaining the operating state of the governor itself, and when determining the fault, the governor controller A fault alarm is issued. The method does not need external special monitoring device, and the governor device can realize the fault diagnosis of the governor main pressure regulating valve by itself, and has the advantages of low cost, strong portability, flexible configuration, and saving system resources. , can generally improve the ability of the main governor valve of the turbine governor to determine the fault. At present, many domestic power plants require the use of new master fault diagnosis methods for fault diagnosis, which can better replace the traditional methods in the past and have greater promotion significance.

The embodiment of the invention further provides a fault diagnosis device for a main pressure regulating valve of a water turbine governor, comprising:

The acquisition module is configured to collect a proportional servo valve feedback signal, a main pressure valve position feedback signal, and a servomotor stroke feedback signal;

The determining module is configured to determine, according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal, whether the hydraulic governor main pressure regulating valve is faulty and/or fault type.

In this embodiment, the acquisition module and the determination module may be program modules stored in the memory, and after being executed by the processor, the collection of various feedback signals and the determination of the fault and the determination of the fault type can be realized.

Optionally, the determining module is configured to perform at least one of the following:

Performing a master-response failure fault determination according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal;

And performing a proportional servo valve feedback change rate of the proportional servo valve feedback signal, a main pressure regulating valve feedback change rate of the main pressure regulating valve position feedback signal, and a servomotor feedback change rate of the servomotor stroke feedback signal, and performing a main Judging with poor movement;

The main valve spool stuck fault determination is performed according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal.

Optionally, the master matching failure fault determination includes: when the signal value of the proportional servo valve feedback signal is a first value, and the signal value of the main pressure regulating valve feedback signal is a second value, The relay stroke feedback signal indicates that the motion of the relay in the non-full-open and non-fully closed state is zero, and when the delay time meets the delay threshold, it is judged that the main failure is detected.

Optionally, the determining that the main matching motion is not smooth comprises: when the proportional servo valve feedback change rate is within a preset first range, the main pressure regulating valve feedback change rate is within a preset second range The servo feedback change rate is slow in the preset third range, and when the delay time meets the delay threshold, it is determined that the main matching motion is not smooth.

Optionally, the main valve spool stuck fault determination includes: when the direction of the proportional servo valve feedback signal is opposite to the direction of the main pressure valve feedback signal, the motion trend of the main pressure valve feedback signal In order to stop and not in the neutral position, the servomotor feedback signal indicates that the servomotor is in the fully open or fully closed position, and when the delay time meets the delay threshold, it is determined that the main valve spool stuck fault occurs.

Optionally, wherein the method is applied inside a turbine governor controller.

The embodiment of the present invention further provides a computer storage medium, where the computer storage medium stores computer executable instructions; after the computer executable instructions are executed, the water turbine governor main body provided by the one or more technical solutions can be implemented. A pressure regulating valve fault diagnosis method, for example, one or more of the methods shown in FIGS. 2 to 5. The computer storage medium can be a non-transitory storage medium.

The above is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention. It should also be considered as the scope of protection of the present invention.

Claims

A fault diagnosis method for a main pressure regulating valve of a water turbine governor, comprising:

Collecting the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal;

According to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal and the servomotor stroke feedback signal, it is judged whether the main governor valve of the turbine governor has a fault and/or fault type.
The method of claim 1 comprising:

The determining, according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal, whether the main governor valve of the turbine governor has a fault and/or fault type, including at least one of the following:

Performing a master-response failure fault determination according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal;

And performing a proportional servo valve feedback change rate of the proportional servo valve feedback signal, a main pressure regulating valve feedback change rate of the main pressure regulating valve position feedback signal, and a servomotor feedback change rate of the servomotor stroke feedback signal, and performing a main Judging with poor movement;

The main valve spool stuck fault determination is performed according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal.
The method for diagnosing a fault of a main pressure regulating valve of a water turbine governor according to claim 1 , wherein the determining of the main matching refusal fault comprises: when the signal value of the feedback signal of the proportional servo valve is a first value, The signal value of the feedback signal of the main pressure regulating valve is a second value, and the servo stroke feedback signal represents that the motion trend of the relay in the non-full opening and non-fully closed state is zero, and the delay time satisfies the first delay When the threshold is reached, it is judged that the main failure is faulty.
The method for diagnosing a fault of a main pressure regulating valve of a water turbine governor according to claim 2, wherein the fault of the main misalignment fault comprises: when the proportional servo valve feedback change rate is in a preset first range The feedback pressure change rate of the main pressure regulating valve is within a preset second range, and the servo relay feedback rate is slow within a preset third range, and when the delay time satisfies the second delay threshold, A malfunction occurs in the main movement.
The method for troubleshooting a main pressure regulating valve of a water turbine governor according to claim 2, wherein the judgment of the main valve spool stuck fault comprises: when the proportional servo valve feedback signal is in a direction with the main match The direction of the pressure feedback signal of the pressure valve is opposite, the movement trend of the feedback signal of the main pressure regulating valve is stopped and not in the middle position, and the feedback signal of the servomotor indicates that the servomotor is in the fully open or fully closed position, and the delay time satisfies the first When the delay threshold is three, it is judged that the main valve plug is stuck.
A method for fault diagnosis of a main governor valve of a water turbine governor according to claim 1, wherein said method is applied inside a turbine governor controller.
The fault diagnosis method for a main pressure regulating valve of a water turbine governor according to any one of claims 1 to 6, wherein when it is judged that a fault occurs, the governor controller issues a fault alarm.
A fault diagnosis device for a main pressure regulating valve of a water turbine governor, comprising:

The acquisition module is configured to collect a proportional servo valve feedback signal, a main pressure valve position feedback signal, and a servomotor stroke feedback signal;

The determining module is configured to determine, according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal, whether the hydraulic governor main pressure regulating valve is faulty and/or fault type.
The device according to claim 8, wherein

The determining module is configured to perform at least one of the following:

Performing a master-response failure fault determination according to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal, and the servomotor stroke feedback signal;

And performing a proportional servo valve feedback change rate of the proportional servo valve feedback signal, a main pressure regulating valve feedback change rate of the main pressure regulating valve position feedback signal, and a servomotor feedback change rate of the servomotor stroke feedback signal, and performing a main Judging with poor movement;

According to the proportional servo valve feedback signal, the main pressure regulating valve position feedback signal and the servo stroke feedback signal, the main valve spool stuck fault determination is performed.
A computer storage medium storing computer executable instructions; the computer executable instructions being executable to implement the method of any one of claims 1 to 7.