阅读说明：本技术 绑带式电机定子线棒介质损耗因数测量系统及其测量方法 (Binding-belt type motor stator bar dielectric loss factor measuring system and measuring method thereof ) 是由 宋春辉 陈庆国 赵冠华 孙文宇 刘洋 于 2021-08-24 设计创作，主要内容包括：本发明提供了绑带式电机定子线棒介质损耗因数测量系统及其测量方法,系统包括高压电源、电压测试装置、电压跟随装置、电流测试装置、介质损耗因数测试装置、数据收集平台,绑带式电极和环境监测装置,高压电源通过保护电阻连接定子线棒与电压测试装置,绑带式电极包裹在定子线棒上,绑带式电极连接电流测试装置,电压跟随装置用于消除绑带式电极上产生的漏电流,环境监测装置测试环境的温度、湿度,电压测试装置与电流测试装置输出数据至介质损耗因数测试装置,介质损耗因数测试装置与环境监测装置的测试数据送至上位机数据收集分析平台。本发明快速地将电极固定在定子线棒上,通过对其充气使导电橡胶电极与定子线棒紧密接触,测试效率高。(The invention provides a bandage type motor stator bar dielectric loss factor measuring system and a measuring method thereof, the system comprises a high-voltage power supply, a voltage testing device, a voltage following device, a current testing device, a dielectric loss factor testing device, a data collecting platform, bandage type electrodes and an environment monitoring device, the high-voltage power supply is connected with the stator bar and the voltage testing device through a protective resistor, the bandage type electrodes are wrapped on the stator bar, the bandage type electrodes are connected with the current testing device, the voltage following device is used for eliminating leakage current generated on the bandage type electrodes, the environment monitoring device is used for testing the temperature and the humidity of the environment, the voltage testing device and the current testing device output data to the dielectric loss factor testing device, and the testing data of the dielectric loss factor testing device and the environment monitoring device are sent to an upper computer data collecting and analyzing platform. The invention quickly fixes the electrode on the stator bar, and the conductive rubber electrode is tightly contacted with the stator bar by inflating the conductive rubber electrode, thereby having high testing efficiency.)

1. A bandage formula motor stator bar dielectric loss factor measurement system which characterized in that: the device comprises a high-voltage power supply (1), a voltage testing device (2), a voltage following device (3), a current testing device (4), a dielectric loss factor testing device (5), a data collecting platform (6), a bandage type electrode (7) and an environment monitoring device (8), wherein the high-voltage power supply (1) is connected with the stator bar and the voltage testing device (2) through a protective resistor, the bandage type electrode (7) is wrapped on the stator bar, the bandage type electrode (7) is connected with the current testing device (4), the voltage following device (3) is used for eliminating leakage current generated on the bandage type electrode (7), the environment monitoring device (8) is used for measuring the temperature and the humidity of a testing environment, the voltage testing device (2) and the current testing device (4) output data to the dielectric loss factor testing device (5), and the testing data of the dielectric loss factor testing device (5) and the environment monitoring device (8) are sent to an upper computer for data collection An analysis platform (6).

2. A taping machine stator bar dielectric loss factor measurement system according to claim 1, wherein: the medium loss factor testing device (5) comprises an A/D conversion circuit, a DSP chip and an RS-485 communication circuit, voltage and current signals are isolated by the medium loss factor testing device (5) through an optical coupler, then are input to the DSP chip for calculation after passing through the A/D conversion circuit, and the result is output to an upper computer data collection and analysis platform (6) through the RS-485 communication circuit.

3. A taping machine stator bar dielectric loss factor measurement system according to claim 1, wherein: the bandage type electrode (7) comprises a left side grounding protection electrode (7-1), a left side equipotential protection electrode (7-2), a magic tape (7-3), a right side equipotential protection electrode (7-4), a right side grounding protection electrode (7-5), a five-hole electrical interface (7-6), an air vent interface (7-7), a fixed bag (7-8) and a measuring electrode (7-9), wherein the measuring electrode (7-9) is fixed in the middle of the fixed bag (7-8), the left side equipotential protection electrode (7-2) and the right side equipotential protection electrode (7-4) are symmetrically arranged on the left side and the right side of the measuring electrode (7-9), and the left side grounding protection electrode (7-2) and the right side grounding protection electrode () are symmetrically fixed at the left end part and the right end part of the fixed bag, the fixing bag (7-8) is of a double-layer sealing structure made of soft woven fabric materials, the fixing bag is rectangular when unfolded, five insertion holes of five-hole electrical connectors (7-6) are connected to five protection electrodes respectively, the ventilation connectors (7-7) are arranged on double-layer gaps of the fixing bag (7-8), the fixing bag (7-8) is inflated and deflated through the ventilation connectors (7-7), the fastening tape (7-3) is arranged on the inner side of the fixing bag (7-8), and accordingly, a sticking area is arranged on the outer side of the fixing bag (7-8).

4. A taping machine stator bar dielectric loss factor measurement system according to claim 3, wherein: the left side equipotential protective electrode (7-2) is connected with the right side equipotential protective electrode (7-4), the voltage following device (3) is connected with the measuring electrode (7-9) and the two connected equipotential protective electrodes, and leakage current generated by the measuring electrode on the binding belt type electrode (7) to the grounding protective electrode is eliminated.

5. A taping machine stator bar dielectric loss factor measurement system according to claim 1, wherein: the voltage testing device (2) comprises a first operational amplifier circuit and a first band-pass filter circuit, the current testing device (4) comprises a second operational amplifier circuit and a second band-pass filter circuit, and the voltage testing device (2) and the current testing device (4) respectively output results to the dielectric loss factor testing device (5) after voltage and current signals are processed by the operational amplifier and conditioned by the band-pass filter through the sampling resistor.

6. A taping machine stator bar dielectric loss factor measurement system according to claim 1, wherein: the dielectric loss factor testing device (5) is provided with an automatic calibration module, the automatic calibration module eliminates additional phase errors of a system, the dielectric loss factor testing device (5) adopts a quasi-synchronous algorithm to sample voltage and current signals, and a harmonic analysis method is used for obtaining a dielectric loss factor testing result through phase comparison of fundamental frequency voltage and current.

7. A taping machine stator bar dielectric loss factor measurement system according to claim 3, wherein: the left grounding protection electrode (7-1), the left equipotential protection electrode (7-2), the right equipotential protection electrode (7-4), the right grounding protection electrode (7-5) and the measuring electrode (7-9) are all made of conductive rubber; the four guard poles were 340mm in length and 40mm in width, and the measurement poles (7-9) were 260mm by 340mm in size.

8. A taping machine stator bar dielectric loss factor measurement system according to claim 1, wherein: and a comprehensive data analysis module is installed in the upper computer data collection and analysis platform (6), the data analysis module comprises the standard data of the dielectric loss factor of the conventional electrode stator bar, the upper computer data collection and analysis platform (6) compares the tested data with the standard data, analyzes the insulation quality of the measured sub-line bar, records, counts, stores and manages the measured result, and gives an evaluation result.

9. A method of measuring a taping machine stator bar dielectric loss factor measurement system according to any one of claims 1 to 8, characterized by: the method specifically comprises the following steps:

firstly, binding the bandage type electrode (7) to a position of a stator bar to be tested, and inflating the fixing bag (7-8) through an air pump to enable the bandage type electrode (7) to be in close contact with the surface of the stator bar;

then, connecting the left and right equipotential protective electrodes together and then connecting the left and right equipotential protective electrodes with a voltage following device, connecting the left and right grounding protective electrodes together and then grounding, and switching on a power supply;

and finally, conditioning the signals through a voltage testing device and a current testing device and sending the conditioned signals to a dielectric loss factor testing device, and outputting a testing result to an upper computer data collection and analysis platform.

Technical Field

The invention belongs to the field of electrical insulation testing, and particularly relates to a binding-belt type motor stator bar dielectric loss factor measuring system and a measuring method thereof.

Background

With the rapid increase of economy, the demand of society on electric power is continuously increased, the installed capacity and rated voltage of the generator are increased, and higher requirements are provided for the operation safety of large-scale generator equipment. The dielectric loss factor is one of important indexes for measuring the insulation quality of a stator bar of the motor and is used for evaluating the heating degree of bar insulation, and the excessive dielectric loss factor can cause the operation temperature of the motor to be too high, the insulation life to be reduced and the motor to be possibly damaged in severe cases. The traditional measuring method is low in automation degree, the bent part of the stator bar is not easy to measure, the stator bar can be damaged to a certain extent, and the problems of additional phase errors of a system, asynchronous sampling and the like can be encountered in the measuring process.

Disclosure of Invention

In view of the above, the invention aims to provide a bandage type motor stator bar dielectric loss factor measuring system and a measuring method thereof, the invention makes up for the defects of the traditional measuring method, can judge the insulation quality of the product by storing and analyzing the test result, and has guiding significance for the production of the motor stator bar.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a bandage type motor stator bar dielectric loss factor measuring system comprises a high-voltage power supply, a voltage testing device, a voltage following device, a current testing device, a dielectric loss factor testing device, a data collecting platform, bandage type electrodes and an environment monitoring device, wherein the high-voltage power supply is connected with the stator bar and the voltage testing device through a protective resistor, the bandage type electrodes are wrapped on the stator bar and are connected with the current testing device, the voltage following device is used for eliminating leakage current generated on the bandage type electrodes, the environment monitoring device is used for measuring the temperature and the humidity of a testing environment, the voltage testing device and the current testing device output data to the dielectric loss factor testing device, and the testing data of the dielectric loss factor testing device and the environment monitoring device are sent to an upper computer data collecting and analyzing platform.

Furthermore, the dielectric loss factor testing device comprises an A/D conversion circuit, a DSP chip and an RS-485 communication circuit, wherein voltage and current signals are isolated by the dielectric loss factor testing device through an optocoupler, then are input into the DSP chip for calculation after passing through the A/D conversion circuit, and the result is output to an upper computer data collection and analysis platform through the RS-485 communication circuit.

Further, the binding-belt type electrode comprises a left side grounding protection electrode, a left side equipotential protection electrode, a binding-belt, a right side equipotential protection electrode, a right side grounding protection electrode, a five-hole electrical interface, a ventilation interface, a fixed bag and a measuring electrode, the measuring electrode is fixed in the middle of the fixed bag, the left side equipotential protective electrode and the right side equipotential protective electrode are symmetrically arranged on the left side and the right side of the measuring electrode, the left grounding protection electrode and the right grounding protection electrode are symmetrically and fixedly arranged at the left end part and the right end part of the fixed bag, the fixing bag adopts a double-layer sealing structure made of soft woven fabric materials, the fixing bag is unfolded to be rectangular, five jacks of a five-hole electrical interface are respectively connected to five protection electrodes, the ventilation interface is arranged on the double-layer gap of the fixed bag, the fixed bag is inflated and deflated through the ventilation interface, the inner side of the fixed bag is provided with a thread gluing belt, and correspondingly, the outer side of the fixed bag is provided with a sticking area.

Furthermore, the left side equipotential protective electrode is connected with the right side equipotential protective electrode, the voltage following device is connected with the measuring electrode and the two connected equipotential protective electrodes, and leakage current generated by the measuring electrode on the binding belt type electrode to the grounding protective electrode is eliminated.

Furthermore, the voltage testing device comprises a first operational amplifier circuit and a first band-pass filter circuit, the current testing device comprises a second operational amplifier circuit and a second band-pass filter circuit, and the voltage testing device and the current testing device respectively output results of voltage and current signals to the dielectric loss factor testing device after the voltage and current signals are processed by the operational amplifier and conditioned by the band-pass filter through the sampling resistor.

Furthermore, the dielectric loss factor testing device is provided with an automatic calibration module, the automatic calibration module eliminates additional phase errors of the system, the dielectric loss factor testing device adopts a quasi-synchronous algorithm to sample voltage and current signals, and a harmonic analysis method is used for obtaining a dielectric loss factor testing result through phase comparison of fundamental frequency voltage and current.

Furthermore, the left side earth guard electrode, the left side equipotential guard electrode, the right side earth guard electrode and the measurement electrode are all made of conductive rubber, the lengths of the four guard electrodes are 340mm, the widths of the four guard electrodes are 40mm, and the size of the measurement electrode is 260mm × 340 mm.

Furthermore, a comprehensive data analysis module is installed in the upper computer data collection and analysis platform, the data analysis module comprises medium loss factor standard data of a conventional electrode stator bar, the upper computer data collection and analysis platform compares the tested data with the standard data, analyzes the insulation quality of the measured sub-line bar, records, counts, stores and manages the measured result, and gives an evaluation result.

A measuring method of a bandage type motor stator bar dielectric loss factor measuring system specifically comprises the following steps:

firstly, binding the bandage type electrode to a position of a stator bar to be tested, and inflating the fixing bag through an air pump to enable the bandage type electrode to be in close contact with the surface of the stator bar;

then, connecting the left and right equipotential protective electrodes together and then connecting the left and right equipotential protective electrodes with a voltage following device, connecting the left and right grounding protective electrodes together and then grounding, and switching on a power supply;

and finally, conditioning the signals through a voltage testing device and a current testing device and sending the conditioned signals to a dielectric loss factor testing device, and outputting a testing result to an upper computer data collection and analysis platform.

Compared with the prior art, the binding-belt type motor stator bar dielectric loss factor measuring system and the measuring method thereof have the following advantages:

the invention adopts the binding belt type electrode to quickly fix the electrode on the stator bar, leads the conductive rubber electrode to be tightly contacted with the stator bar by inflating the electrode, improves the testing efficiency, and adopts the automatic calibration function and the quasi-synchronization algorithm to eliminate the system error.

The dielectric loss factor testing device processes the voltage and current signals through the DSP digital signal processing chip, the calculation speed is high, and the result is directly sent to an upper computer data collection and analysis platform.

The upper computer data collection and analysis platform has the advantages of concise software part interface, visual information display and convenient operation, and the database can store a large amount of test data and provide effective data for product quality control.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic structural diagram of a taping motor stator bar dielectric loss factor measurement system;

FIG. 2 is a view of a taping electrode configuration in a taping motor stator bar dielectric loss factor measurement system;

FIG. 3 is a combined structure diagram of a voltage testing device, a current testing device and a dielectric loss factor testing device of a bandage type motor stator bar dielectric loss factor measuring system.

FIG. 4 is a data processing flow chart of a dielectric loss factor testing device of a bandage type motor stator bar dielectric loss factor measuring system.

Description of reference numerals:

the device comprises a 1-high-voltage power supply, a 2-voltage testing device, a 3-voltage following device, a 4-current testing device, a 5-dielectric loss factor testing device, a 6-upper computer data collecting platform, a 7-binding belt type electrode, a 7-1-left side grounding protection electrode, a 7-2-left side equipotential protection electrode, a 7-3-binding belt, a 7-4-right side equipotential protection electrode, a 7-5-right side grounding protection electrode, a 7-6-five-hole electrical interface, a 7-7-ventilation interface, a 7-8-fixing bag, a 7-9-measuring electrode and an 8-environment monitoring device.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in fig. 1-3, a bandage type motor stator bar dielectric loss factor measuring system comprises a high-voltage power supply 1, a voltage testing device 2, a voltage following device 3, a current testing device 4, a dielectric loss factor testing device 5, a data collecting platform 6, a bandage type electrode 7 and an environment monitoring device 8, the high-voltage power supply 1 is connected with a stator bar and a voltage testing device 2 through a protective resistor, the bandage type electrode 7 is wrapped on the stator bar, the bandage type electrode 7 is connected with a current testing device 4, the voltage following device 3 is used for eliminating leakage current generated on the bandage type electrode 7, the environment monitoring device 8 measures the temperature and humidity of the test environment, the voltage testing device 2 and the current testing device 4 output data to the dielectric loss factor testing device 5, and the testing data of the dielectric loss factor testing device 5 and the environment monitoring device 8 are sent to the upper computer data collection and analysis platform 6.

The dielectric loss factor testing device 5 comprises an A/D conversion circuit, a DSP chip and an RS-485 communication circuit, voltage and current signals are isolated by the dielectric loss factor testing device 5 through an optocoupler, then are input to the DSP chip for calculation after passing through the A/D conversion circuit, and the result is output to the upper computer data collection and analysis platform 6 through the RS-485 communication circuit. The method specifically comprises the following steps: the dielectric loss factor testing device 5 obtains the conditioned voltage and current signals to perform high-speed A/D conversion, the conversion result is transmitted to the DSP chip TMS320F28335, and the voltage and current signal relation is analyzed through a quasi-synchronization algorithm to obtain the result.

The bandage type electrode 7 comprises a left side grounding protection electrode 7-1, a left side equipotential protection electrode 7-2, a magic tape 7-3, a right side equipotential protection electrode 7-4, a right side grounding protection electrode 7-5, a five-hole electrical interface 7-6, an air vent interface 7-7, a fixed bag 7-8 and a measuring electrode 7-9, wherein the measuring electrode 7-9 is fixed in the middle of the fixed bag 7-8, the left side equipotential protection electrode 7-2 and the right side equipotential protection electrode 7-4 are symmetrically arranged on the left side and the right side of the measuring electrode 7-9, the left side grounding protection electrode 7-2 and the right side grounding protection electrode are symmetrically and fixedly arranged at the left end part and the right end part of the fixed bag, the fixed bag 7-8 is of a double-layer sealing structure made of soft woven fabric material and is unfolded to be rectangular, five jacks of the five-hole electrical interface 7-6 are respectively connected to five protection electrodes, the ventilation interface 7-7 is arranged on a double-layer gap of the fixed bag 7-8, the fixed bag 7-8 is inflated and deflated through the ventilation interface 7-7, the inner side of the fixed bag 7-8 is provided with a fastening tape 7-3, and correspondingly, the outer side of the fixed bag 7-8 is provided with a sticking area.

The left side equipotential protective electrode is connected with the right side equipotential protective electrode, the voltage following device is connected with the measuring electrode and the two connected equipotential protective electrodes, and leakage current of the measuring electrode on the binding belt type electrode to the grounding protective electrode is eliminated.

The left side grounding protection electrode 7-1, the left side equipotential protection electrode 7-2, the right side equipotential protection electrode 7-4 and the right side grounding protection electrode 7-5 are all arranged in a straight line shape, the grounding protection level is used for preventing currents on two sides from flowing into the measuring electrode 7-9 to influence a test result, and the equipotential protection level is used for eliminating leakage currents between the measuring electrode 7-9 and the grounding protection level. The electrodes are made of conductive rubber materials and can be in close contact with the stator bar, the electrodes are uniform electric fields, and the electrodes adopt chamfer structures to eliminate measurement errors caused by electric field concentration.

The voltage testing device 2 comprises a first operational amplifier circuit and a first band-pass filter circuit, the current testing device 4 comprises a second operational amplifier circuit and a second band-pass filter circuit, and the voltage testing device 2 and the current testing device 4 respectively output results of voltage and current signals to the dielectric loss factor testing device 5 after the voltage and current signals are processed by the operational amplifier and conditioned by the band-pass filter through the sampling resistor. The method specifically comprises the following steps: the voltage and current signals extracted by the voltage testing device 2 and the current testing device 4 are amplified through an AD8022 programmable instrument amplifier, and then other frequency interference signals are filtered through a 50Hz band-pass filter consisting of OP07, so that the accuracy of the signals is improved.

Fig. 4 shows a data processing flow of the dielectric loss factor testing device 5, where the dielectric loss factor testing device 5 has an automatic calibration module, the automatic calibration module eliminates additional phase errors of the system, the dielectric loss factor testing device 5 performs sampling processing on voltage and current signals by using a quasi-synchronous algorithm, and obtains a dielectric loss factor testing result by comparing phases of fundamental frequency voltage and current by using a harmonic analysis method.

The dielectric loss factor testing device is provided with an automatic calibration module, and the automatic calibration module is used for eliminating additional phase offset introduced after amplification, filtering and the like of a system. The same-phase standard sine wave is input into the system, the dielectric loss factor is tan delta ', the measured value of the dielectric loss factor is tan delta' in the normal test, and the actual value of the dielectric loss factor is calculatedThereby eliminating the additional phase error.

The medium loss factor testing device adopts quasi-synchronous algorithm sampling to solve the problem of asynchronous system sampling, a quasi-synchronous window function can be obtained by weighting and processing sampling data, the original signal data is multiplied by the window function, the processed signal data has the frequency cycle characteristic of the original data, and the synchronization error of the signal is effectively reduced.

The left grounding protection electrode 7-1, the left equipotential protection electrode 7-2, the right equipotential protection electrode 7-4, the right grounding protection electrode 7-5 and the measuring electrode 7-9 are all made of conductive rubber; the four guard poles were 340mm in length and 40mm in width, with the dimensions of the measurement poles 7-9 being 260mm by 340 mm.

And a comprehensive data analysis module is installed in the upper computer data collection and analysis platform 6, the data analysis module comprises the standard data of the dielectric loss factor of the conventional electrode stator bar, the upper computer data collection and analysis platform 6 compares the tested data with the standard data, analyzes the insulation quality of the measured sub-line bar, records, counts, stores and manages the measured result, and gives an evaluation result.

A measuring method of a bandage type motor stator bar dielectric loss factor measuring system specifically comprises the following steps:

firstly, binding the bandage type electrode 7 to a position of a stator bar to be tested through a sticking area and a sticking belt 7-3, wherein the electrode faces the stator bar and is in contact with the stator bar, and inflating the fixing bag 7-8 through an air pump to enable the bandage type electrode 7 to be in close contact with the surface of the stator bar;

then, connecting the left equipotential protective electrode and the right equipotential protective electrode together and then connecting the left equipotential protective electrode and the right equipotential protective electrode with the voltage following device 3, connecting the left grounding protective electrode and the right grounding protective electrode together and then grounding, operating the upper computer to control the test to start, and switching on the power supply;

and finally, conditioning the signals by a voltage testing device and a current testing device, sending the conditioned signals to a dielectric loss factor testing device 5, inputting the results after A/D conversion into a DSP chip for calculation, and outputting the test results to an upper computer data collection and analysis platform 6.

The environment monitoring device 8 in the application is an existing structure and comprises a humidity sensor and a temperature sensor, wherein the temperature sensor and the humidity sensor collect signals, the signals are input into a single chip microcomputer after A/D conversion, and then the signals are sent to an upper computer data collection and analysis platform 6 through the single chip microcomputer. The voltage follower 3 in the present application is a voltage follower, which is a conventional structure and is not described herein again.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.