A detection system and method for shaft vibration sensor with clamp

Abstract

The invention discloses a detection system and method for a shaft vibration sensor with a card. A standard vibration sensor is located on a vibration table, a bracket is fixed on the vibration table, the shaft vibration sensor is located on the bracket, a shaft vibration metal disc is located on the standard vibration sensor, the shaft vibration sensor is connected to a card computer software system via a preamplifier, a frame and a card, the card is located at a measured point of the frame, the preamplifier is connected to a DC voltage regulator and a digital multimeter, the vibration table is connected to a vibration controller via a power amplifier, the vibration controller is connected to a standard vibration sensor, and the vibration controller is connected to a comparison method computer software system. The system and method can accurately realize the detection of the shaft vibration sensor with a card.

Description

Technical Field

[0001] The invention relates to a detection system and method, and in particular to a detection system and method for a shaft vibration sensor with a clamp. Background Art

[0002] The amplitude of vibration during the operation of the unit is an important indicator of the unit's safety and economic operation. Excessive vibration means that the unit has serious defects. Excessive vibration amplitude will cause many hazards, such as: the speed control system is unstable, which in turn causes speed control system accidents; the bearing is cracked, the fastening screws are loosened and broken; the generator excitation components are loose and damaged, and even the unit foundation is damaged, which intensifies the vibration; the fatigue strength of the rotating parts is reduced, which causes damage to the blades and impellers; the end shaft seal is worn; the sliding pin is worn; the partition steam seal is worn; the emergency circuit breaker malfunctions, etc. Therefore, during the start-up and shutdown and operation of the unit, the vibration of the bearing must be closely monitored to protect the safety of the unit equipment and personnel.

[0003] Generally speaking, equipment operators will send the shaft vibration sensor to the laboratory for testing before installing the sensor and the card or during overhaul, but will rarely confirm the metering performance and usage parameters of the supporting card. This ignores the technical requirements of actual on-site applications, and the accuracy and protection of the turbine monitoring system will be flawed and uncertain.

[0004] The accurate measurement of the shaft vibration sensor with clamps and the issuance of correct protection actions are crucial to the safe and stable operation of the unit. Therefore, the overall detection of the shaft vibration sensor with clamps is of great significance to its practical application. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a detection system and method for a shaft vibration sensor with a clamp, which can accurately realize the detection of the shaft vibration sensor with a clamp.

[0006] To achieve the above-mentioned purpose, the shaft vibration sensor with a card detection system of the present invention comprises a standard vibration sensor, a vibration controller, a power amplifier, a vibration table, a shaft vibration sensor, a preamplifier, a card, a rack, a comparison method computer software system, a card computer software system, a DC voltage regulator, a digital multimeter, a shaft vibration metal disc and a bracket;

[0007] The standard vibration sensor is located on the vibration table, the bracket is fixed on the vibration table, the shaft vibration sensor is located on the bracket, the shaft vibration metal disk is located on the standard vibration sensor, the shaft vibration sensor is connected to the card computer software system via the preamplifier, the frame and the card, the card is located at the measured point of the frame, the preamplifier is connected to the DC voltage regulator and the digital multimeter, the vibration table is connected to the vibration controller via the power amplifier, the vibration controller is connected to the standard vibration sensor, and the vibration controller is connected to the comparison method computer software system.

[0008] The standard vibration sensor is connected to the vibration controller via a cable.

[0009] The vibration controller is a dynamic signal analyzer.

[0010] The shaft vibration metal disc is rigidly mounted above the standard vibration sensor, and the shaft vibration sensor is fixed on a bracket with adjustable initial gap in a non-contact manner.

[0011] The shaft vibration sensor is connected to the preamplifier via a cable.

[0012] The output cable of the standard vibration sensor is fixed in an S-shaped manner.

[0013] The gap voltage between the shaft vibration sensor and the shaft vibration metal disk is measured by a digital multimeter to be -10V or -12V.

[0014] The detection method of the shaft vibration sensor with a clamping piece of the present invention comprises the following steps:

[0015] 1) The card computer software system obtains the output value of the card, and the comparison method computer software system obtains the vibration signal of the standard vibration sensor;

[0016] 2) Calculate the relative error of each measured point of the card according to the output value of the card and the vibration signal of the standard vibration sensor;

[0017] 3) Calibrate the card according to the relative errors of each measured point of the card.

[0018] The present invention has the following beneficial effects:

[0019] During specific operation of the detection system and method for the shaft vibration sensor with a card component described in the present invention, the card component computer software system obtains the output value of the card component, the comparison method computer software system obtains the vibration signal of the standard vibration sensor, and the relative error of each measured point of the card component is calculated based on the output value of the card component and the vibration signal of the standard vibration sensor. The card component is calibrated based on the relative error of each measured point of the card component to ensure accurate measurement of the vibration condition of the bearing and issuance of correct protection actions, thereby providing guarantee for the safe operation of the generator set equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the present invention.

[0021] Among them, 1 is a standard vibration sensor, 2 is a vibration controller 2, 3 is a power amplifier, 4 is a vibration table, 5 is a shaft vibration sensor, 6 is a preamplifier, 7 is a card, 8 is a rack, 9 is a comparison method computer software system, 10 is a card computer software system, 11 is a DC voltage regulator, 12 is a digital multimeter, 13 is a shaft vibration metal disc, and 14 is a bracket. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only an embodiment of a part of the present invention, not all embodiments, and is not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concepts disclosed in the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0023] The accompanying drawings show schematic diagrams of structures according to embodiments disclosed in the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0024] refer to Figure 1 The shaft vibration sensor with a card detection system of the present invention comprises a standard vibration sensor 1, a vibration controller 2, a power amplifier 3, a vibration table 4, a shaft vibration sensor 5, a preamplifier 6, a card 7, a rack 8, a comparison method computer software system 9, a card computer software system 10, a DC voltage regulator 11, a digital multimeter 12, a shaft vibration metal disc 13 and a bracket 14;

[0025] The standard vibration sensor 1 is located on the vibration table 4, the bracket 14 is fixed on the vibration table 4, the shaft vibration sensor 5 is located on the bracket 14, the shaft vibration metal disc 13 is located on the standard vibration sensor 1, the shaft vibration sensor 5 is connected to the card computer software system 10 via the preamplifier 6, the frame 8 and the card 7, the card 7 is located at the measured point of the frame 8, the preamplifier 6 is connected to the DC voltage source 11 and the digital multimeter 12, the vibration table 4 is connected to the vibration controller 2 via the power amplifier 3, the vibration controller 2 is connected to the standard vibration sensor 1, and the vibration controller 2 is connected to the comparison method computer software system 9;

[0026] Among them, the shaft vibration metal disk 13 is installed above the standard vibration sensor 1, and the shaft vibration sensor 5 is installed on a bracket 14 with an adjustable initial gap; the standard vibration sensor 1 is connected to the vibration controller 2 through a cable, and the vibration controller 2 is a dynamic signal analyzer. The shaft vibration metal disk 13 is rigidly installed above the standard vibration sensor 1, and the shaft vibration sensor 5 is fixed in a non-contact manner on the bracket 14 with good rigidity and adjustable initial gap, and the shaft vibration sensor 5 is connected to the preamplifier 6 via a cable; the output cable of the standard vibration sensor 1 is fixed in an S-shaped manner to prevent severe shaking, collision and friction during measurement; the shaft vibration sensor 5 is fixed in a non-contact manner on the bracket 14 with good rigidity and adjustable initial gap, so that the gap voltage between the shaft vibration sensor 5 and the shaft vibration metal disk 13 can be measured by a digital multimeter 12 as -10V or -12V.

[0027] The specific working process of the present invention is:

[0028] The vibration control device 2 and the power amplifier 3 provide a vibration signal source for the vibration table 4, the card computer software system 10 obtains the output value of the card 7, and the comparison method computer software system 9 obtains the vibration signal detected by the standard vibration sensor 1;

[0029] During the detection, the DC voltage regulator 11 provides 24V power to the preamplifier 6, and then the bracket 14 is adjusted so that the gap voltage between the shaft vibration sensor 5 and the shaft vibration metal disk 13 measured by the digital multimeter 12 is -10V or -12V;

[0030] Amplitude linearity detection: select a working reference frequency point of 55Hz, and give vibration amplitudes of 20μm, 50μm, 100μm, 150μm, 200μm, 250μm, 300μm and 350μm in turn. Each time the vibration amplitude is changed, after it stabilizes, record the actual output amplitude and current signal output value of the card 7;

[0031] Frequency response detection: select a constant vibration amplitude of 100μm, and set the frequencies of 10Hz, 20Hz, 40Hz, 50Hz, 60Hz, 80Hz, and 100Hz in sequence. At each frequency point, after stabilization, record the actual output amplitude and current signal output value of the card 7;

[0032] Alarm value and protection action value detection: At the reference frequency point of 55 Hz (avoiding the power frequency), the corresponding standard voltage and displacement signal are given to the vibration table 4, and the output value and standard output value of the alarm state and protection action state of the card 7 are recorded according to the indicator light display of the card 7.

[0033] The relative measurement error of the card 7 is calculated, and the card 7 is calibrated according to the relative measurement error of the card 7, wherein:

[0034] Among them, the relative error of amplitude linearity is:

[0035]

[0036] The relative error of the frequency response is:

[0037]

[0038] The relative error of current output is:

[0039]

[0040] Where Δx L is the relative error of each measured point of the card 7, x i is the value of each measured point of the card 7, x0 is the preset standard value, Δx f is the relative error of each measured point of the card 7, x i is the value of each measured point of card 7, x r is the standard value of card 7 at a certain reference frequency point, ΔA is the relative error of the current output of each measured point of card 7, A i is the output value of each measured point of card component 7, and A0 is the output standard value of card component 7.

[0041] The output of the card component 7 is calibrated according to the relative measurement error of the card component 7 .

[0042] When the relative measurement error is within the maximum allowable error range, the alarm value and protection action value of the card 7 meet the on-site application requirements.

[0043] The card 7 determines the measured points according to the measurement range. The measured points are distributed as evenly as possible according to the range. The measured points should cover the measured points required for actual on-site work and protection actions. The vibration controller 2 and the power amplifier 3 provide measurement vibration sources according to the determined measured points. After stabilization, the comparison method computer software system 9 and the card computer software system 10 respectively collect standard values ​​and measurement values ​​of the card 7 at each measured point.

[0044] The amplitude linearity, frequency response and relative error of current output of card 7 meet the technical indicators of ±5%;

[0045] In actual on-site applications, the alarm values ​​and protection action values ​​of the bearing vibration settings of common units such as 300MW and 600MW are 125μm and 250μm respectively. By adjusting the output voltage value of the vibration controller 2 at the reference frequency point of 55Hz, the standard voltage and displacement values ​​under the alarm and protection action display status of card 7 and the output current and displacement values ​​of card 7 are recorded as its alarm value and protection action value to ensure that the alarm and protection action display status of card 7 is correct without non-display or erroneous display, and the alarm value and protection action value meet the technical index requirements of actual on-site application.

[0046] The present invention is characterized in that:

[0047] It can accurately determine whether the relative measurement error of the amplitude linearity, frequency response and current output of the shaft vibration sensor with clamp exceeds the maximum allowable error value;

[0048] Can determine whether the shaft vibration sensor with clamps meets the requirements for bearing vibration monitoring in thermal power plants, and ensure the accuracy and reliability of the turbine monitoring system;

[0049] Able to provide shaft vibration sensor with clamp adjustment to ensure the accuracy of measured parameters.

[0050] It can accurately measure the alarm value and protection action value of the shaft vibration sensor with a clamp. During the start-up, shutdown and operation of the unit, it can measure the vibration of the bearing and make correct alarm indications and protection actions to ensure the safety of the unit equipment and personnel.

Claims

1. A method for detecting a shaft vibration sensor with a clamp, characterized in that: A detection system based on a shaft vibration sensor with a card, the detection system comprising a standard vibration sensor (1), a vibration controller (2), a power amplifier (3), a vibration table (4), a shaft vibration sensor (5), a preamplifier (6), a card (7), a rack (8), a comparison method computer software system (9), a card computer software system (10), a DC voltage regulator (11), a digital multimeter (12), a shaft vibration metal disc (13) and a bracket (14); The standard vibration sensor (1) is located on the vibration table (4), the bracket (14) is fixed on the vibration table (4), the shaft vibration sensor (5) is located on the bracket (14), the shaft vibration metal disc (13) is located on the standard vibration sensor (1), the shaft vibration sensor (5) is connected to the card computer software system (10) via the preamplifier (6), the frame (8) and the card (7), the card (7) is located at the measured point of the frame (8), the preamplifier (6) is connected to the DC voltage source (11) and the digital multimeter (12), the vibration table (4) is connected to the vibration controller (2) via the power amplifier (3), the vibration controller (2) is connected to the standard vibration sensor (1), and the vibration controller (2) is connected to the comparison method computer software system (9); The following steps are involved: 1) The card component computer software system (10) obtains the output value of the card component (7), and the comparison method computer software system obtains the vibration signal of the standard vibration sensor (1); 2) calculating the relative error of each measured point of the card component (7) according to the output value of the card component (7) and the vibration signal of the standard vibration sensor (1); 3) calibrating the card component (7) according to the relative errors of each measured point of the card component (7); Amplitude linearity detection: select a working reference frequency point of 55 Hz, and set the vibration amplitudes of 20 μm, 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm and 350 μm in sequence. Each time the vibration amplitude is changed, after it stabilizes, record the actual output amplitude and current signal output value of the card (7); Frequency response detection: select a constant vibration amplitude of 100 μm, and set the frequencies of 10 Hz, 20 Hz, 40 Hz, 50 Hz, 60 Hz, 80 Hz, and 100 Hz in sequence. At each frequency point, after stabilization, record the actual output amplitude and current signal output value of the card (7); Alarm value protection action value detection: at a reference frequency of 55 Hz, the vibration table (4) is given a corresponding standard voltage and displacement signal, and the output value and standard output value of the alarm state and protection action state of the card component (7) are recorded according to the indicator light display of the card component (7); The relative measurement error of the card component (7) is calculated, and the card component (7) is calibrated according to the relative measurement error of the card component (7), wherein: Among them, the relative error of amplitude linearity is: The relative error of the frequency response is: The relative error of current output is: Among them, Δ x L is the relative error of each measured point of the fixture (7), x i The values ​​of each measured point of the card (7) are indicated. x 0 is the preset standard value, Δ x f is the relative error of each measured point of the fixture (7), x i The values ​​of each measured point of the card (7) are indicated. x r is the standard value of the card (7) at a certain reference frequency point, Δ A is the relative error of the current output of each measured point of the card (7), A i is the output value of each measured point of card 7, A 0 is the output standard value of the card (7).

2. The detection method of the shaft vibration sensor with a clamp according to claim 1 is characterized in that: The standard vibration sensor (1) is connected to the vibration controller (2) via a cable.

3. The detection method of the shaft vibration sensor with a clamp according to claim 1, characterized in that: The vibration controller (2) is a dynamic signal analyzer.

4. The detection method of the shaft vibration sensor with a clamp according to claim 1, characterized in that: The shaft vibration metal disc (13) is rigidly mounted above the standard vibration sensor (1), and the shaft vibration sensor (5) is fixed on a bracket (14) with an adjustable initial gap in a non-contact manner.

5. The detection method of the shaft vibration sensor with a clamp according to claim 1, characterized in that: The shaft vibration sensor (5) is connected to the preamplifier (6) via a cable.

6. The method for detecting a shaft vibration sensor with a clamp according to claim 1, characterized in that: The output cable of the standard vibration sensor (1) is fixed in an S-shaped manner.

7. The detection method of the shaft vibration sensor with a clamp according to claim 1, characterized in that: The gap voltage between the shaft vibration sensor (5) and the shaft vibration metal disc (13) is measured by a digital multimeter (12) to be -10V or -12V.

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