CN213091753U

CN213091753U - Non-contact shaft voltage measuring device

Info

Publication number: CN213091753U
Application number: CN202021363096.5U
Authority: CN
Inventors: 苏显贺; 白仕光; 佟尧
Original assignee: Datang Northeast Electric Power Test and Research Institute Co Ltd
Current assignee: Datang Northeast Electric Power Test and Research Institute Co Ltd
Priority date: 2020-07-13
Filing date: 2020-07-13
Publication date: 2021-04-30
Anticipated expiration: 2030-07-13

Abstract

The utility model relates to a non-contact shaft voltage measuring device, which comprises a double-channel sensor probe, a power supply unit, a signal processing unit, a DSP core board and a display unit; the dual-channel sensor probe is electrically connected with the DSP core board through the signal processing unit, and the display unit and the power supply unit are electrically connected with the DSP core board; the dual-channel sensor probe is arranged on the side of the generator shaft in a non-contact mode and used for acquiring a voltage signal in direct proportion to the voltage to be detected, and the voltage signal is input to the DSP core board after being processed by the signal processing unit; the DSP core board is used for processing the voltage signals to obtain a measured voltage result and outputting the measured voltage result to the display unit for displaying. The utility model discloses avoided measuring device and generator rotor direct contact, compared with traditional contact axle voltage measurement and reduced the damage to generator rotor, improved the measuring security.

Description

Non-contact shaft voltage measuring device

Technical Field

The utility model discloses electrical test equipment technical field especially relates to a non-contact axle voltage measurement device.

Background

When the large-scale generator operates, shaft voltage is induced on a generator shaft due to the reasons of magnetic circuit asymmetry, a static excitation system, an electrostatic effect and the like. Normally the shaft voltage is low, but when the shaft voltage is high, imperfections in the surface of the bearing pads, inadequate lubrication or flow, abnormal generator vibration, etc. can cause oil film breakdown, resulting in metallic contact between the shaft and the bearing pads, resulting in considerable shaft currents, up to several hundred amperes or even thousands of amperes, which can be sufficient to burn the journal and the bearing pads. The bearing corrosion caused by the shaft voltage is an accelerating process, metal on the surface of a bearing bush can be locally melted by one-time discharging, metal particles are formed in an oil film, the insulation of the oil film is damaged, discharging is easier to occur, chain reaction is formed, unit vibration is aggravated until the unit is forced to quit operation, and hidden dangers are brought to on-site safety production. Therefore, the value of the shaft voltage is periodically detected to monitor the change of the shaft voltage.

At present, the shaft voltage measurement mostly adopts a soft copper wire (carbon brush) to contact a rotating shaft of a generator, and the operation is simple through the reading of a high internal resistance alternating current voltmeter. However, the rotor rotating at high speed may not only cause damage to the generator rotor by adopting contact measurement, but also threaten the safety of testing personnel.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a non-contact axle voltage measuring device to solve above-mentioned technical problem.

The utility model provides a non-contact shaft voltage measuring device, which comprises a double-channel sensor probe, a power supply unit, a signal processing unit, a DSP core board and a display unit; the dual-channel sensor probe is electrically connected with the DSP core board through the signal processing unit, and the display unit and the power supply unit are electrically connected with the DSP core board;

the dual-channel sensor probe is arranged on the side of the generator shaft in a non-contact mode and used for acquiring a voltage signal in direct proportion to the voltage to be detected, and the voltage signal is input to the DSP core board after being processed by the signal processing unit;

the DSP core board is used for processing the voltage signals to obtain a measured voltage result and outputting the measured voltage result to the display unit for displaying.

Furthermore, the device also comprises a communication unit and a peripheral function unit, wherein the communication unit and the peripheral function unit are electrically connected with the DSP core board.

Furthermore, the signal processing unit comprises a signal amplifying circuit and an isolating circuit, and the signal amplifying circuit is electrically connected with the isolating circuit.

Further, the power supply unit includes a battery module and a DC-DC converter circuit.

Furthermore, the dual-channel sensor probe adopts a voltage sensor based on the electric field coupling principle, wherein one channel is used for measuring the interference voltage of a field test environment.

Further, the communication unit adopts a GSM module or a GPRS module.

Further, the display unit adopts a capacitive touch liquid crystal screen.

By means of the scheme, the non-contact shaft voltage measuring device has the following technical effects:

1) the direct contact between the measuring device and the generator rotor is avoided, compared with the traditional contact type shaft voltage measurement, the damage to the generator rotor is reduced, and the measuring safety is improved.

2) The dual-channel sensor probe is adopted, one channel measures the interference voltage of the field test environment, the interference of the field test environment is eliminated, and the measurement accuracy can be improved.

3) The DSP microprocessor and the capacitive touch liquid crystal screen are adopted, so that the measurement is rapid and accurate, the data can be remotely monitored, guided and analyzed, and the reliable operation in various severe environments such as indoor environment, outdoor environment and the like can be met.

The above description is only an overview of the technical solution of the present invention, and in order to make the technical means of the present invention clearer and can be implemented according to the content of the description, the following detailed description is made with reference to the preferred embodiments of the present invention and accompanying drawings.

Drawings

Fig. 1 is a block diagram of the non-contact shaft voltage measuring device of the present invention;

fig. 2 is a circuit diagram of the signal processing unit of the non-contact shaft voltage measuring device of the present invention.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

Referring to fig. 1 and 2, the present embodiment provides a non-contact shaft voltage measuring device, which includes a dual-channel sensor probe 1, a power supply unit 2, a signal processing unit 3, a communication unit 4, a peripheral function unit 5, a DSP core board (microprocessor) 6, and a display unit 7. The dual-channel sensor probe 1 is electrically connected with the DSP core board 6 through the signal processing unit 3, and the power supply unit 2, the communication unit 4, the peripheral function unit 5, the display 7 and the DSP core board 6 are electrically connected.

The signal processing unit 3 comprises a signal amplifying circuit and an isolating circuit, and the signal amplifying circuit is electrically connected with the isolating circuit.

The power supply unit 2 includes a battery module, a DC-DC converter circuit, and is used to supply power to the entire apparatus.

The dual-channel sensor probe 1 measures a voltage signal in direct proportion to the measured voltage, the signal is input into the DSP core board 6 after being processed by the signal processing unit 3, and the measured voltage is displayed through the display unit 7 after the input signal is processed by the DSP core board 6.

In this embodiment, the dual-channel sensor probe 1 employs a voltage sensor based on the electric field coupling principle, wherein one channel measures the interference voltage of the field test environment, the interference of the field test environment is eliminated, and the measurement accuracy can be improved.

In this embodiment, the communication unit 4 adopts a GSM/GPRS module, and the measurement device can meet the communication requirements of indoor and outdoor work, and can realize remote monitoring guidance and analyze voltage data. The peripheral function unit 5 mainly includes functions of key operation control, data storage, and the like.

In this embodiment, the DSP core board 6 has a dedicated hardware multiplier, which can be used to implement various digital signal processing algorithms quickly.

In this embodiment, the display unit 7 adopts a capacitive touch liquid crystal screen, so that the number of the entity keys in the circuit board can be reduced, the processing difficulty of the subsequent shell is reduced, the capacitive touch screen can well sense slight and quick touch, prevent scraping, is not afraid of dust, water and dirt, and is suitable for being used in severe environment.

As shown in fig. 2, the electrical signal measured by the dual-channel sensor probe 1 is amplified by the signal processing unit, isolated by the isolation circuit, and limited by the voltage regulator tube, and then output to the DSP core board 6. Isolation and amplitude limiting ensure that the DSP of the control chip cannot be burnt out when the voltage of the front end is overlarge.

The non-contact shaft voltage measuring device has the following technical effects:

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A non-contact type shaft voltage measuring device is characterized by comprising a double-channel sensor probe, a power supply unit, a signal processing unit, a DSP core board and a display unit; the dual-channel sensor probe is electrically connected with the DSP core board through the signal processing unit, and the display unit and the power supply unit are electrically connected with the DSP core board;

2. The non-contact axle voltage measuring device of claim 1, further comprising a communication unit and a peripheral function unit, said communication unit and peripheral function unit being electrically connected to said DSP core board.

3. The non-contact shaft voltage measuring device according to claim 1, wherein the signal processing unit comprises a signal amplifying circuit and an isolating circuit, and the signal amplifying circuit is electrically connected with the isolating circuit.

4. The contactless shaft voltage measuring device according to claim 1, wherein the power supply unit includes a battery module and a DC-DC converter circuit.

5. The non-contact shaft voltage measuring device of claim 1, wherein the dual channel sensor probe employs a voltage sensor based on electric field coupling principle, wherein one channel is used to measure the interference voltage of a field test environment.

6. The noncontact shaft voltage measuring device of claim 2, wherein said communication unit employs a GSM module or a GPRS module.

7. The noncontact axis voltage measuring device of claim 1, wherein the display unit adopts a capacitive touch liquid crystal screen.