Insulation acquisition terminal and monitoring terminal for large shaft of large-scale hydro-generator

Abstract

The utility model provides a large-scale hydro-generator large shaft insulation acquisition terminal, which is applied to a large-scale hydro-generator and comprises a first carbon brush, a second carbon brush, a third carbon brush, a fourth carbon brush, an upper guide outer layer bearing insulation monitoring unit, an upper guide inner layer bearing insulation monitoring unit and a shaft voltage acquisition unit. The first carbon brush, the second carbon brush, the third carbon brush and the fourth carbon brush make contact with a large shaft, the first carbon brush and the second carbon brush are installed in a generator head slip ring chamber, the third carbon brush and the fourth carbon brush are installed in a waterwheel chamber, and the upper guide outer layer bearing insulation monitoring unit is connected with the first carbon brush and the second carbon brush. The upper conductor inner layer bearing insulation monitoring unit is connected with the second carbon brush and the third carbon brush. And the shaft voltage acquisition unit is connected with the fourth carbon brush. The large shaft insulation resistance value and the shaft voltage value can be monitored in a remote, online and real-time manner, the data real-time performance is improved, the fault processing timeliness is further improved, and the normal operation of a unit is ensured.

Description

Technical Field

[0001] The utility model relates to the field of large hydrogenerator monitoring, in particular to a large hydrogenerator shaft insulation acquisition terminal and a monitoring terminal. Background Technique

[0002] Due to reasons such as uneven air gap between the stator and rotor of a large hydrogenerator, large local magnetic resistance of the stator core, and asymmetric magnetic circuit, the stator magnetic field of the generator is unbalanced, which will generate an alternating magnetic flux intersecting the shaft and an axial induced electromotive force, i.e., shaft voltage, on the rotor of the generator. When the shaft voltage is too large, it will damage the insulation between the shaft collar and the large shaft, resulting in the upper guide bearing being burned due to overheating.

[0003] At present, large hydrogenerator shaft insulation monitoring systems at home and abroad cannot remotely and online monitor the actual resistance value of the shaft insulation. When the large shaft rotates, the constant force spring of the shaft carbon brush is constantly twitched, the spring is fatigued and aged, and the constant force spring coils of the shaft insulation carbon brush and the grounding carbon brush are broken, resulting in the spring falling off and the carbon brush being completely separated from the large shaft. During the operation of the generator, it is very difficult for the operation and maintenance personnel to discover such faults through inspections. When an actual shaft insulation fault occurs, the shaft insulation monitoring device refuses to operate, which will cause the fault to expand and major faults such as bearing burning to occur. Content of the Utility Model

[0004] Aiming at the problems existing in the prior art, a large hydrogenerator shaft insulation acquisition terminal and a monitoring terminal are provided, which can remotely and real-time collect and monitor the insulation condition of the generator shaft.

[0005] The first aspect of the utility model proposes a large hydrogenerator shaft insulation acquisition terminal, which is applied to a large hydrogenerator and includes a first carbon brush, a second carbon brush, a third carbon brush, a fourth carbon brush, an upper guide outer bearing insulation monitoring unit, an upper guide inner bearing insulation monitoring unit, and a shaft voltage acquisition unit; wherein, the first carbon brush, the second carbon brush, the third carbon brush, and the fourth carbon brush are all in contact with the large shaft. The first carbon brush and the second carbon brush are respectively installed in the slip ring chamber of the generator head, and the third carbon brush and the fourth carbon brush are installed in the waterwheel chamber. The upper guide outer bearing insulation monitoring unit is respectively connected to the first carbon brush and the second carbon brush and outputs the insulation resistance value between the first carbon brush and the second carbon brush; the upper guide inner bearing insulation monitoring unit is respectively connected to the second carbon brush and the third carbon brush and outputs the insulation resistance value between the second carbon brush and the third carbon brush; the shaft voltage acquisition unit is connected to the fourth carbon brush and is used to output the shaft voltage.

[0006] As a preferred solution, the first carbon brush is a shaft collar carbon brush, the second carbon brush is a copper foil carbon brush, and the third carbon brush is a large shaft carbon brush.

[0007] As a preferred solution, the fourth carbon brush is a shaft voltage monitoring carbon brush for collecting shaft voltage.

[0008] As a preferred solution, the first carbon brush, the second carbon brush, and the fourth carbon brush are not grounded, while the third carbon brush is grounded.

[0009] As a preferred solution, both the upper guide outer bearing insulation monitoring unit and the upper guide inner bearing insulation monitoring unit are implemented using SINEAX V604 general programmable transmitters.

[0010] In the second aspect of the present utility model, a large shaft insulation monitoring terminal for a large hydrogenerator is proposed, which is realized on the basis of the large shaft insulation acquisition terminal described in the first aspect. It further includes an A / D conversion unit, a data processing unit, a D / A conversion unit, a power station monitoring system, and a display unit connected in sequence. The A / D conversion unit simultaneously receives the data output by each unit from the upper guide outer bearing insulation monitoring unit, the upper guide inner bearing insulation monitoring unit, and the shaft voltage acquisition unit, and completes analog-to-digital conversion. The data processing unit is used for data filtering and logic processing. The D / A conversion unit is used for analog-to-digital conversion. The power station monitoring system is used to receive and store the large shaft insulation resistance value and shaft voltage output by the D / A conversion unit, where the large shaft insulation resistance value includes the upper guide outer bearing insulation resistance value and the upper guide inner bearing insulation resistance value. The display unit is used to display the large shaft insulation resistance value and shaft voltage in real time.

[0011] As a preferred solution, it further includes an alarm unit connected to the power station monitoring system. The alarm unit is preset with a threshold range for the large shaft insulation resistance value and shaft voltage, and is used to generate an alarm when the large shaft insulation resistance value and shaft voltage exceed the threshold range.

[0012] As a preferred solution, it further includes a printing unit connected to the power station monitoring system, which is used to print the large shaft insulation resistance value and shaft voltage obtained in real time.

[0013] Compared with the prior art, the beneficial effects of adopting the above technical solutions are as follows:

[0014] 1. Transmit the collected large shaft insulation resistance value and shaft voltage value to the power station monitoring system through digital signals, realizing remote, online, and real-time monitoring of the generator's large shaft insulation, and effectively improving the operation stability and safety of the large shaft insulation system.

[0015] 2. By means of the alarm system, the alarm level is set to judge the type of main shaft insulation fault and the treatment measures, solving the problem that when there are abnormalities in the main shaft insulation measurement circuit, poor contact or no contact between the main shaft insulation carbon brush and the main shaft, the operation and maintenance personnel cannot detect such defects in time. It ensures the operation stability of the generator set and the maintenance safety, provides technical guarantee for the safe operation of large hydropower stations, and lays a good foundation for the safe and stable operation of the power grid. Brief Description of the Drawings

[0016] Figure 1 The figure is a schematic diagram of the main shaft insulation acquisition terminal of a large hydrogenerator proposed in an embodiment of the present utility model.

[0017] Figure 2 The figure is a schematic diagram of the main shaft insulation monitoring terminal of a large hydrogenerator proposed in an embodiment of the present utility model.

[0018] Reference Numerals: 1 - First carbon brush, 2 - Second carbon brush, 3 - Third carbon brush, 4 - Upper guide outer bearing insulation monitoring unit, 5 - Upper guide inner bearing insulation monitoring unit, 6 - Fourth carbon brush, 7 - Shaft voltage acquisition unit, 8 - A / D conversion unit, 9 - Data processing unit, 10 - D / A conversion unit, 11 - Power station monitoring system, 12 - Alarm unit, 13 - Printing unit, 14 - Display unit. Detailed Embodiment

[0019] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar modules or modules with the same or similar functions from beginning to end. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present application and should not be construed as a limitation to the present application. On the contrary, the embodiments of the present application include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0020] In order to monitor the main shaft insulation situation in real time, an embodiment of the present utility model proposes a main shaft insulation acquisition terminal for a large hydrogenerator, which is applied to a large hydrogenerator and can realize the acquisition of the main shaft insulation resistance value for subsequent judgment of the insulation situation and improve the timeliness of fault handling.

[0021] Specifically, please refer to Figure 1, the acquisition terminal includes a first carbon brush 1, a second carbon brush 2, a third carbon brush 3, a fourth carbon brush 6, an upper guide outer bearing insulation monitoring unit 4, an upper guide inner bearing insulation monitoring unit 5, and a shaft voltage acquisition unit 7; among them, the first carbon brush 1, the second carbon brush 2, the third carbon brush 3, and the fourth carbon brush 6 are all in contact with the large shaft. The first carbon brush 1 and the second carbon brush 2 are respectively installed in the slip ring chamber at the generator head, and the third carbon brush 3 and the fourth carbon brush 6 are installed in the waterwheel chamber. The upper guide outer bearing insulation monitoring unit 4 is respectively connected to the first carbon brush 1 and the second carbon brush 2 to output the insulation resistance value between the first carbon brush and the second carbon brush; the upper guide inner bearing insulation monitoring unit 5 is respectively connected to the second carbon brush 2 and the third carbon brush 3 to output the insulation resistance value between the second carbon brush and the third carbon brush; the shaft voltage acquisition unit 7 is connected to the fourth carbon brush 6 for outputting the shaft voltage.

[0022] In this embodiment, the first carbon brush 1 is a shaft collar carbon brush, the second carbon brush 2 is a copper foil carbon brush, the third carbon brush 3 is a large shaft carbon brush, and the fourth carbon brush 6 is a shaft voltage monitoring carbon brush for collecting the shaft voltage. During actual testing, the first carbon brush 1, the second carbon brush 2, and the fourth carbon brush 6 are not grounded, and the third carbon brush 3 is grounded.

[0023] The upper guide outer bearing insulation monitoring unit 4 and the upper guide inner bearing insulation monitoring unit 5 are used to collect the insulation conditions of the generator bearings and output them in the form of 4-20mA analog signals. Specifically, the parts of the large shaft monitored by the upper guide outer bearing insulation monitoring unit 4 and the upper guide inner bearing insulation monitoring unit 5 are different. The upper guide outer bearing insulation monitoring unit 4 is respectively connected to the first carbon brush 1 and the second carbon brush 2 to monitor the insulation of the outer bearing and output a 4-20mA analog signal, which can reflect the magnitude of the outer bearing insulation resistance value. Similarly, the upper guide inner bearing insulation monitoring unit 4 is respectively connected to the second carbon brush 2 and the third carbon brush 3 to monitor the insulation of the inner bearing and output a 4-20mA analog signal, which can reflect the magnitude of the inner bearing insulation resistance value. In one embodiment, the upper guide outer bearing insulation monitoring unit 4 and the upper guide inner bearing insulation monitoring unit 5 can be implemented using a SINEAX V604 general-purpose programmable transmitter.

[0024] At the same time, the shaft voltage acquisition unit 7 cooperates with the shaft voltage monitoring carbon brush to complete the acquisition of the shaft voltage and outputs it in the form of a 4-20mA analog signal.

[0025] Through the upper guide outer bearing insulation monitoring unit 4, the upper guide inner bearing insulation monitoring unit 5, and the shaft voltage acquisition unit 7, the insulation data of the generator bearings and the shaft voltage can be collected in real time.

[0026] Furthermore, this embodiment also proposes a large shaft insulation monitoring terminal for a large hydrogenerator, which is used to judge the insulation state of the large shaft according to the data collected by the acquisition terminal and issue an alarm. Please refer to Figure 2 , the monitoring terminal mainly includes an A / D conversion unit 8, a data processing unit 9, a D / A conversion unit 10, a power station monitoring system 11, and a display unit 14 that are connected in sequence; the A / D conversion unit 8 is simultaneously connected to the upper guide outer bearing insulation monitoring unit, the upper guide inner bearing insulation monitoring unit 5, and the shaft voltage acquisition unit 7 to receive the data output by each unit and complete analog-to-digital conversion; the data processing unit 9 is used for data filtering and logical processing; the D / A conversion unit 10 is used for analog-to-digital conversion; the power station monitoring system 11 is used to receive and store the large shaft insulation resistance value and the shaft voltage output by the D / A conversion unit 10. The large shaft insulation resistance value includes the upper guide outer bearing insulation resistance value (obtained by the upper guide outer bearing insulation monitoring unit) and the upper guide inner bearing insulation resistance value (obtained by the upper guide inner bearing insulation monitoring unit); the display unit 14 is used to display the large shaft insulation resistance value and the shaft voltage in real time, so as to more intuitively understand the operation of the large generator.

[0027] In this monitoring terminal, the large shaft insulation analog quantity collected by the acquisition terminal can be displayed as the real-time large shaft insulation resistance value in the display unit 14 after A / D conversion, data processing, and D / A conversion. Similarly, the shaft voltage analog quantity collected by the acquisition terminal can be displayed as the real-time shaft voltage value in the display unit 14 after A / D conversion, data processing, and D / A conversion.

[0028] In practical applications, it can be remotely transmitted after being converted into a digital quantity. That is to say, the monitoring terminal can be set in a split mode. The A / D conversion unit 8 and the data processing unit 9 can be set on-site with the acquisition terminal, used to convert the output analog quantity into a digital quantity, perform preliminary processing, and then transmit the digital quantity signal. After receiving it remotely, it is converted back into an analog quantity. Through the transmission of digital quantity signals, interference in the transmission process is avoided, and problems such as frequent false alarms of 4-20mA analog quantities caused by external environmental factors are solved, ensuring the correctness and reliability of the transmitted data. In one embodiment, the data processing unit can include a CPU, a memory, a clock, a human-machine interface, etc., to realize data filtering, logical processing of the collected data, saving data, and viewing data.

[0029] In one embodiment, the monitoring terminal further includes an alarm unit 12, which is connected to the power station monitoring system 11; the alarm unit 12 is preset with a threshold range of the large shaft insulation resistance value and the shaft voltage, and is used to generate an alarm when the large shaft insulation resistance value and the shaft voltage exceed the threshold range. Specifically, according to the preset threshold range, this embodiment gives a total of three alarm levels: the first alarm level, the second alarm level, and the third alarm level; among them,

[0030] First alarm level: When the real-time large shaft insulation resistance value is less than the minimum value of its threshold range and the real-time shaft voltage value is greater than the maximum value of its threshold range, it indicates that the insulation of the upper guide bearing has decreased and the shaft voltage is abnormal. Immediate shutdown is required for a comprehensive inspection. In one embodiment, the minimum value of the threshold range of the large shaft insulation resistance value is 2.5 kΩ; the maximum value of the threshold range of the shaft voltage value is set to 30V.

[0031] Second alarm level: When the real-time large shaft insulation resistance value is less than the minimum value of its threshold range and the real-time shaft voltage value is less than the maximum value of its threshold range, it indicates that the insulation of the upper guide bearing has decreased and the shaft voltage is normal. It is necessary to observe the operation of the unit and stop the machine for inspection if necessary.

[0032] Third alarm level: When the real-time measured large shaft insulation resistance value is greater than the maximum value of its threshold range and the real-time shaft voltage value is less than the maximum value of its threshold range, it indicates that the measurement circuit is abnormal or the contact between the large shaft insulation carbon brush and the large shaft is poor. It is necessary to check the analog data acquisition circuit.

[0033] In practical applications, the alarm conditions can be adjusted as needed. For example, if the insulation resistance values of the inner layer and outer layer of the upper guide bearing are both less than 2.5 kΩ and the shaft voltage is less than 30V, enhanced inspection is required and inspection is carried out after shutdown. As long as one of the insulation resistance values of the inner layer of the upper guide bearing and the outer layer of the upper guide bearing is less than 2.5 kΩ or the shaft voltage is greater than 30V, if one of the three conditions is met, an abnormal shaft insulation alarm is reported.

[0034] In order to facilitate data collection and analysis during faults, in one embodiment, the monitoring terminal further includes a printing unit 13. The printing unit 13 is connected to the power station monitoring system 11 and is used to print the real-time obtained large shaft insulation resistance value and shaft voltage. In a preferred embodiment, the printing unit 13 is implemented by a printer.

[0035] The large shaft insulation acquisition terminal and monitoring terminal of the large hydrogenerator proposed by the present utility model realize remote, online and real-time monitoring of the large shaft insulation resistance value and shaft voltage value by collecting the large shaft insulation resistance value and shaft voltage value in real time and transmitting them to the power station monitoring system through multiple channels; when the real-time measured large shaft insulation resistance value and shaft voltage value are not within the set value range, the monitoring system immediately alarms, effectively improving the operation stability and maintenance safety of the large shaft insulation system.

[0036] Embodiment 1

[0037] This embodiment proposes a large shaft insulation acquisition terminal for a large hydro-generator, which is applied to a large hydro-generator and includes a first carbon brush, a second carbon brush, a third carbon brush, a fourth carbon brush, an upper guide outer bearing insulation monitoring unit, an upper guide inner bearing insulation monitoring unit, and a shaft voltage acquisition unit; wherein, the first carbon brush, the second carbon brush, the third carbon brush, and the fourth carbon brush are all in contact with the large shaft. The first carbon brush and the second carbon brush are respectively installed in the slip ring chamber of the generator head, and the third carbon brush and the fourth carbon brush are installed in the water turbine chamber. The upper guide outer bearing insulation monitoring unit is respectively connected to the first carbon brush and the second carbon brush and outputs the insulation resistance value between the first carbon brush and the second carbon brush; the upper guide inner bearing insulation monitoring unit is respectively connected to the second carbon brush and the third carbon brush and outputs the insulation resistance value between the second carbon brush and the third carbon brush; the shaft voltage acquisition unit is connected to the fourth carbon brush and is used to output the shaft voltage.

[0038] Embodiment 2

[0039] Based on Embodiment 1, in this embodiment, the first carbon brush is a shaft collar carbon brush, the second carbon brush is a copper foil carbon brush, and the third carbon brush is a large shaft carbon brush.

[0040] Embodiment 3

[0041] Based on Embodiment 1, in this embodiment, the fourth carbon brush is a shaft voltage monitoring carbon brush for collecting the shaft voltage.

[0042] Embodiment 4

[0043] Based on Embodiment 1, in this embodiment, the first carbon brush, the second carbon brush, and the fourth carbon brush are not grounded, and the third carbon brush is grounded.

[0044] Embodiment 5

[0045] Based on Embodiment 1, in this embodiment, the upper guide outer bearing insulation monitoring unit, the upper guide inner bearing insulation monitoring unit, and the shaft voltage acquisition unit output through a 4 - 20mA analog quantity, and this analog quantity reflects the size of the insulation resistance value.

[0046] Embodiment 6

[0047] Based on Embodiment 1, in this embodiment, both the upper guide outer bearing insulation monitoring unit and the upper guide inner bearing insulation monitoring unit are implemented by using a SINEAX V604 general programmable transmitter.

[0048] Embodiment 7

[0049] This embodiment proposes a large shaft insulation monitoring terminal for a large hydro-generator, which is implemented on the basis of the large shaft insulation acquisition terminal described in Embodiment 1. It further includes an A / D conversion unit, a data processing unit, a D / A conversion unit, a power station monitoring system, and a display unit connected in sequence. The A / D conversion unit is simultaneously connected to the upper guide outer bearing insulation monitoring unit, the upper guide inner bearing insulation monitoring unit, and the shaft voltage acquisition unit to receive the parameters output by each unit and complete analog-to-digital conversion. The data processing unit is used for data filtering and logical processing. The D / A conversion unit is used for analog-to-digital conversion. The power station monitoring system is used to receive and store the large shaft insulation resistance value and shaft voltage output by the D / A conversion unit, where the large shaft insulation resistance value includes the upper guide outer bearing insulation resistance value and the upper guide inner bearing insulation resistance value. The display unit is used to display the large shaft insulation resistance value and shaft voltage in real time.

[0050] Embodiment 8

[0051] On the basis of Embodiment 7, this embodiment further includes an alarm unit, which is connected to the power station monitoring system. The alarm unit is preset with a threshold range of the large shaft insulation resistance value and shaft voltage, and is used to generate an alarm when the large shaft insulation resistance value and shaft voltage exceed the threshold range.

[0052] Embodiment 9

[0053] On the basis of Embodiment 8, in the alarm unit of this embodiment, according to the set threshold range, a first alarm level, a second alarm level, and a third alarm level are set. Among them,

[0054] First alarm level: When the real-time large shaft insulation resistance value is less than the minimum value of its threshold range and the real-time shaft voltage value is greater than the maximum value of its threshold range, it indicates that the upper guide bearing insulation has decreased and the shaft voltage is abnormal, and immediate shutdown is required for a comprehensive inspection.

[0055] Second alarm level: When the real-time large shaft insulation resistance value is less than the minimum value of its threshold range and the real-time shaft voltage value is less than the maximum value of its threshold range, it indicates that the upper guide bearing insulation has decreased and the shaft voltage is normal, and the operation of the unit needs to be observed and shutdown inspection is required if necessary.

[0056] Third level: When the real-time measured large shaft insulation resistance value is greater than the maximum value of its threshold range and the real-time shaft voltage value is less than the maximum value of its threshold range, it indicates that the measurement circuit is abnormal or the contact between the large shaft insulation carbon brush and the large shaft is poor, and the analog data acquisition circuit needs to be checked.

[0057] Embodiment 10

[0058] On the basis of Embodiment 6, this embodiment further includes a printing unit, which is connected to the power station monitoring system and is used to print the large shaft insulation resistance value and shaft voltage obtained in real time.

[0059] The present utility model can be preferably realized through Embodiment 1 to Embodiment 10.

[0060] It should be noted that in the description of the embodiments of the present utility model, unless otherwise clearly defined and limited, the terms "arrangement" and "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection, or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations; the accompanying drawings in the embodiments are used to clearly and completely describe the technical solutions in the embodiments of the present utility model. Obviously, the described embodiments are some, rather than all, of the embodiments of the present utility model. Usually, the components of the embodiments of the present utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0061] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A large-scale hydro-generator shaft insulation collection terminal, characterized in that: It is used in large-scale hydro-turbine generators, including a first carbon brush, a second carbon brush, a third carbon brush, a fourth carbon brush, an upper guide outer bearing insulation monitoring unit, an upper guide inner bearing insulation monitoring unit and a shaft voltage acquisition unit; wherein the first carbon brush, the second carbon brush, the third carbon brush and the fourth carbon brush are all in contact with the main shaft, the first carbon brush and the second carbon brush are respectively installed in the generator head slip ring chamber, the third carbon brush and the fourth carbon brush are installed in the waterwheel chamber, the upper guide outer bearing insulation monitoring unit is respectively connected to the first carbon brush and the second carbon brush, and outputs the insulation resistance value between the first carbon brush and the second carbon brush; the upper guide inner bearing insulation monitoring unit is respectively connected to the second carbon brush and the third carbon brush, and outputs the insulation resistance value between the second carbon brush and the third carbon brush; the shaft voltage acquisition unit is connected to the fourth carbon brush for outputting the shaft voltage.

2. The large-scale hydro-generator shaft insulation acquisition terminal according to claim 1 is characterized in that: The first carbon brush is a shaft collar carbon brush, the second carbon brush is a copper foil carbon brush, and the third carbon brush is a large shaft carbon brush.

3. The large-scale hydro-generator shaft insulation acquisition terminal according to claim 1 is characterized in that: The fourth carbon brush is a shaft voltage monitoring carbon brush, which is used to collect shaft voltage.

4. The large-scale hydro-generator shaft insulation acquisition terminal according to claim 1 is characterized in that: The first carbon brush, the second carbon brush and the fourth carbon brush are not grounded, and the third carbon brush is grounded.

5. The large-scale hydro-generator shaft insulation acquisition terminal according to claim 1 is characterized in that: The upper guide outer bearing insulation monitoring unit and the upper guide inner bearing insulation monitoring unit are both implemented using SINEAX V604 universal programmable transmitter.

6. A large-scale hydro-turbine generator shaft insulation monitoring terminal, implemented on the basis of the large-scale hydro-turbine generator shaft insulation acquisition terminal according to any one of claims 1 to 5, characterized in that: It also includes an A / D conversion unit, a data processing unit, a D / A conversion unit, a power station monitoring system and a display unit connected in sequence; the A / D conversion unit simultaneously receives the parameters output by each unit together with the upper guide outer bearing insulation monitoring unit, the upper guide inner bearing insulation monitoring unit and the shaft voltage acquisition unit, and completes the analog-to-digital conversion; the data processing unit is used for data filtering and logic processing; the D / A conversion unit is used for analog-to-digital conversion; the power station monitoring system is used to receive and store the large shaft insulation resistance value and shaft voltage output by the D / A conversion unit, wherein the large shaft insulation resistance value includes the upper guide outer bearing insulation resistance value and the upper guide inner bearing insulation resistance value; the display unit is used to display the large shaft insulation resistance value and the shaft voltage in real time.

7. The large-scale hydro-generator shaft insulation monitoring terminal according to claim 6 is characterized in that: It also includes an alarm unit connected to the power station monitoring system; the alarm unit is preset with a threshold range of the main shaft insulation resistance value and the shaft voltage, and is used to generate an alarm when the main shaft insulation resistance value and the shaft voltage exceed the threshold range.

8. The large-scale hydro-generator shaft insulation monitoring terminal according to claim 6 is characterized in that: It also includes a printing unit, which is connected to the power station monitoring system and is used to print the large shaft insulation resistance value and shaft voltage obtained in real time.

Images