Non-contact wriggling monitoring device

Abstract

The utility model relates to the technical field of monitoring creeping of a large shaft of a hydroelectric generating set of a hydropower station, in particular to a non-contact creeping monitoring device. The problems that in the prior art, a depended wheel mechanism is tightly attached to a large shaft, the surface of the large shaft is polluted, regular cleaning is needed, the depended wheel mechanism breaks down, and starting-up of a unit is affected are solved. According to the technical scheme, the device comprises a PLC, the PLC is respectively connected with an LED display, an alarm, a membrane switch, an analog quantity output module and a plurality of measuring sensors, the distance between an inductive head of each measuring sensor and a tooth surface of a speed measuring fluted disc of a unit is 2mm, the measuring sensors are inductance type proximity switches, the number of the measuring sensors is five, and the number of the measuring sensors is five. The PLC controller is powered by the power supply unit, and the PLC controller is a Panasonic PLC FPOR series.

Description

Technical Field

[0001] The utility model relates to the technical field of monitoring the creep of a main shaft of a hydro-turbine generator set in a hydropower station, and in particular to a non-contact creep monitoring device. Background Art

[0002] After the hydropower station turbine generator set is shut down, the ball valve and guide vane are closed and the rotor stops at a certain position. However, in actual use, due to the processing accuracy and installation errors, the ball valve and guide vane cannot be completely sealed. Therefore, the ball valve and guide vane will leak when the unit is shut down, causing the unit to creep. If measures are not taken in time, the bearing bushing will be burned out under long-term low-speed rotation, affecting the safe operation of the unit.

[0003] The existing method of measuring creep is to install a supporting wheel mechanism next to the main shaft of the unit. After the unit is shut down, the supporting wheel mechanism is pushed out and pressed against the main shaft. When the unit creeps, the main shaft drives the supporting wheel rotating wheel to rotate at the same time, meeting the alarm requirements and outputting an alarm signal for use in the unit automation process. However, since the supporting wheel is in close contact with the main shaft of the unit during the creep monitoring process, it will cause a certain amount of pollution to the surface of the main shaft. In this way, the surface of the main shaft needs to be cleaned regularly, which is labor-intensive and time-consuming. In addition, since the supporting wheel is installed at a high position, it is inconvenient to clean the main shaft. When the unit is started, the supporting wheel mechanism needs to be rebounded. If the internal structure of the supporting wheel mechanism fails, it will cause the unit to fail to start, affecting the progress of the work. Utility Model Content

[0004] The utility model provides a non-contact creep monitoring device to solve the problems in the prior art that the supporting wheel mechanism is close to the main shaft, causing pollution to the main shaft surface and requiring regular cleaning, and the supporting wheel mechanism fails, affecting the start-up of the unit.

[0005] In order to overcome the problems existing in the prior art, the technical solution adopted by the utility model is: a non-contact creep monitoring device, including a PLC controller, the PLC controller is respectively connected to an LED display, an alarm, a membrane switch, an analog output module and a plurality of measuring sensors, and the distance between the sensing head of the measuring sensor and the tooth surface of the unit speed measuring gear disc is 2mm.

[0006] Furthermore, the measuring sensor is an inductive proximity switch.

[0007] Furthermore, the number of measuring sensors is 5.

[0008] Further, the PLC controller is powered by a power supply unit.

[0009] Furthermore, the PLC controller is Panasonic PLC FPOR series.

[0010] Compared with the prior art, the utility model has the following advantages:

[0011] 1) The utility model adopts a programmable PLC controller, which has stable operation and strong anti-interference ability, and adopts LED digital tube display mode, making the device work stably and reliably.

[0012] 2) The measuring sensor of the utility model adopts a high-performance inductive proximity switch, which has high measuring accuracy, is easy to use, and is easy to install and maintain.

[0013] 3) The utility model adopts a creep monitoring method and non-contact measurement to prevent contamination of the large shaft surface and eliminate startup failures.

[0014] 4) The detection toothed disc of the utility model can be shared with the toothed disc of the speed measuring system, thus saving costs.

[0015] 5) The LED display of the utility model can visually view the unit creep alarm status, the real-time value of the alarm angle, and output 1 creep switch alarm and 1 creep angle analog signal.

[0016] 6) The utility model can set parameters directly on the LED display, which is convenient and quick, and parameters such as monitoring cycle and delay time can be set through a membrane switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a system block diagram of the utility model.

[0018] Figure 2 Sensor installation diagram.

[0019] Figure 3 This is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] The utility model adopts a non-contact method to measure the creep of the main shaft of the unit. A gear disc is encircled on the main shaft of the unit (which can be shared with the unit speed measuring gear disc). Five inductive proximity switches are installed horizontally with the gear disc. Figure 2As shown, the induction signal is passed and blocked by the synchronous speed of the gear disc and the generator, so as to obtain the electric pulse signal, and transmit the electric pulse signal to the back-end monitoring device. After analysis and calculation inside the device, the angle value of the creeping is output. When the preset alarm limit is reached, the creeping alarm signal is output. At the same time, the analog signal of the creeping angle value can be output for use by the monitoring system.

[0022] The structure specifically adopted in the utility model is as follows Figure 1 As shown, it includes a PLC controller, which is respectively connected to an LED display, an alarm, a membrane switch, an analog output and 5 measuring sensors. The sensing head of the measuring sensor is horizontally set with the speed measuring gear of the unit. The PLC controller outputs a switch alarm and an analog signal (4-20mA), and the membrane switch button is connected to the PLC controller.

[0023] As an implementation method in this embodiment, the PLC controller is powered by a power supply unit.

[0024] As an implementation method in this embodiment, the measuring sensor is an inductive proximity switch.

[0025] As an implementation method in this embodiment, the PLC controller is Panasonic PLC FPOR series.

[0026] As an implementation method in this embodiment, the measurement sensor model is TURCK NI5-G12-AP6X.

[0027] When the utility model is working: the power is turned on, the five sensors on site input the collected data into the PLC controller, the PLC controller outputs the switch alarm and analog signal through internal calculation, and the PLC controller displays the corresponding alarm state and alarm value through the LED digital tube. The operating parameters are set through the membrane button.

[0028] See circuit Figure 3 When the utility model works: start the power supply, the five sensors on site input the collected data into the PLC controller, the PLC controller outputs the switch alarm and analog signal through internal calculation, and the PLC controller displays the corresponding alarm state and alarm value through the LED digital tube. The operating parameters are set through the membrane switch.

[0029] The measuring principle of this utility model is as follows:

[0030] When the turbine generator set creeps, when the rotation angle reaches between 1.5-2.0 degrees, a creep alarm signal is issued. Refer to the sensor installation position diagram Figure 2 , the angle between a tooth top and a tooth groove is 2 degrees, and 5 inductive proximity switches are used to monitor creep, covering an area of ​​0.5*4=2.0 degrees. Assume that the position of probe 1 is as follows Figure 2 As shown, it is just aligned with the top of the tooth. The position of the 2# probe lags 0.5 degrees relative to the position of the 1# probe, the 3# probe lags 1.0 degrees relative to the position of the 1# probe, the 4# probe lags 1.5 degrees relative to the position of the 1# probe, and the 5# probe lags 2.0 degrees relative to the position of the 1# probe. In this way, when the unit creeps, each probe will jump to the rising and falling edges. The condition for detecting creep alarm is that when the 1# probe rises, the timing starts. During the monitoring cycle, if the 2# probe rises, the unit rotation angle is 0.5 degrees, if the 3# probe rises, the unit rotation angle is 1.0 degrees, and if the 4# probe rises, the unit rotation angle is 1.5 degrees. At this time, it is determined that the unit creeps and outputs the creep alarm signal. After the alarm occurs, it is delayed for a certain time (the monitoring cycle can be set). During this time, if any probe does not jump again, the creep alarm will be reset. In the input signal part, the stop command and the start command signals are added. When the stop command signal is received, it delays for a certain period of time and starts to monitor the creep. When the start command signal is received, the creep monitoring is exited.

[0031] The following three situations illustrate the accuracy of the creep alarm.

[0032] In the first case, probe 1 is just before the jump. If creep occurs at this time, probe 1 will jump immediately. When the jump of probe 4 is detected, a creep alarm signal will be issued. The creep alarm angle is 1.5 degrees.

[0033] In the second case, probe No. 1 is just after the jump. If creep occurs at this time, the creep alarm will only occur when the jump of probe No. 2 is detected first and then the jump of probe No. 5 is detected. Then the creep alarm angle is 2.0 degrees.

[0034] In the third case, the probe is located between the above two cases. If a peristaltic alarm occurs at this time, the angle of the peristaltic alarm is between 1.5 degrees and 2.0 degrees.

[0035] In the above description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed above.

[0036] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A non-contact peristalsis monitoring device, characterized in that: It comprises a PLC controller, which is respectively connected with an LED display, an alarm, a membrane switch, an analog output module and a plurality of measuring sensors, and the tooth surface spacing between the induction head of the measuring sensor and the speed measuring gear disc of the unit is 2mm.

2. A non-contact peristalsis monitoring device according to claim 1, characterized in that: The measuring sensor is an inductive proximity switch.

3. A non-contact peristalsis monitoring device according to claim 1 or 2, characterized in that: There are five measuring sensors.

4. A non-contact peristalsis monitoring device according to claim 3, characterized in that: The PLC controller is powered by a power supply unit.

5. A non-contact peristalsis monitoring device according to claim 4, characterized in that: The PLC controller is Panasonic PLC FPOR series.

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