Application research of three-phase asynchronous motor detection technology

Introduction:

Equipment fault Diagnosis Technology is a combination of engineering and theory of comprehensive technology, it has greatly promoted the enterprise equipment production maintenance system reform, the greatest degree of reducing economic losses, for enterprises to obtain as much economic benefits. Motor fault diagnosis is a branch of equipment fault diagnosis technology, three-phase asynchronous motor automation testing platform for the enterprise to provide a considerable convenience, it can automatically complete the three-phase induction motor all the detection, and the detection data for further management and analysis, for quality inspection and maintenance personnel to provide reliable data basis. Therefore, it is also the focus of motor production enterprises. This paper focuses on the analysis and research of three-phase asynchronous motor detection system produced by Tianjin Communication Broadcasting Group, and explores the application of three asynchronous motor detection platform.

1. System Features

? The system is used for the factory inspection and maintenance of three-phase induction motor, and the single station design

? Automated test flow for quick and easy

? Customized Operation interface, professional control software, simple and clear interface module

? Modular test function for rapid service and deployment for each test unit

? With Java language development, and network and database seamless link, with excellent portability and cross-platform deployment capabilities;

? The system adopts standardized test instrument, which is easy to replace and repair, and has excellent repeatability and stability.

1.1. Customizable detection function

The system supports: DC resistance test, insulation resistance test, no-load test, blocking test, rotational speed steering, turn-to-turns withstand voltage, power frequency withstand voltage, gas tightness test and oil injection function.

PC-side software is developed in Java language, has the ability to test the modular deployment of functions, according to the different needs of users, customized combination of different test projects.

1.2. Can connect to network server for data management

The system seamlessly docking network server, call the basic data file on the server, use as the standard of detection;

Users can perform data statistics, data management and quality analysis according to the test results of each test module, and provide data cloud statistics service for other departments within the company.

1.3. Local Data service support available

In the case of unavailability of network service, the system provides local data service support, which helps users to set up local database, so that users can collect test data.

1.4. Software core testing process can expand docking different test equipment and network services

Software can be expanded to connect to a variety of peripheral testing equipment and customized network services, each detection project is a separate component, can be freely splicing combination, to adapt to the customer's different detection environment and detection process. At the same time, the software's human-machine interface and detection device drivers are based on a unified API operating interface, according to customer needs, flexible interface and testing equipment to adjust.

2. System composition

Figure 2-1 System composition

The system is composed of PC (including test software), test instrument, test sensor, PLC control module, sweep code gun and switch circuit. which

(1) PC: running motor testing software;

? Through the RS232 port: with the test instruments and other peripheral devices such as scanning gun to carry out instruction interaction, so as to achieve the control of peripheral devices and measurement data read;

? Through the network interface: With the customer company server for motor basic data and access and test data upload;

? Through the network interface: with the PLC for information interaction;

? touch screen display;

? Integrated PCI serial port expansion card (RS232) for each test equipment connection;

(2) test instrument: including DC resistance tester, insulation resistance tester, power meter, frequency converter, voltage tester, turn-to-turn tester, temperature sensor and other equipment, these devices through the RS232 port and PC communication, according to the instructions of the host computer to carry out various tests, and the measurement data can be transmitted to the host computer.

(3) test sensor: including the measuring speed of the table head, measuring the oil-filling function of the flowmeter and flow valve. These test sensors are connected with PLC and are controlled by PLC and collected by the data.

(4) plc Measurement and Control module: PLC external test sensor, switch circuit and sound light alarm device, and through the network port and PC connected. Responsible for data acquisition and control of peripheral test sensor, and be responsible for identifying the status of switching circuit, the PC can interact with the data through the network port.

(5) Scan the code gun: through the USB port connected to the PC, the motor barcode can be swept into the test software, the test software will sweep the code value as the primary key, to the server to retrieve the relevant data of the Test motor.

(6) Switching circuit: the console of the "Start", "Stop", "emergency stop" and other physical buttons, these buttons access to the PLC, by the PLC is responsible for identifying the switch/closed state of the button, the PLC then the button state through the network port to the detection software.

3. Detection function

Scanning gun swept into the motor of the "number", the test software according to the "ticket" to the server to query the number of the machine under test the model, serial number, quantity, computer characteristics, oil, oil and other related information. Subsequent tests use this data as a benchmark to continue to retrieve data from the database and obtain the data required for testing.

3.1. DC resistance test

The software realizes the operation prompt and the test conclusion display to the three-phase asynchronous motor's DC resistance test. The software obtains the data measured by the Millivolt (the value of the DC resistance between any two phases) and the temperature value of the system test, converting the measured data and then comparing it with the standard resistance range at a given temperature. Then the unbalance of three-phase resistor is calculated, then compared with the standard value, the conclusion is finally reached.

3.2. Insulation Resistance test

The software realizes the testing of the insulation resistance of the three-phase induction motor and shows the test results. The software obtains to test the test equipment to the electric motor winding and the wiring board and so on the insulating piece to the shell's insulating ability testing data, compares with the standard insulation resistance value under the given temperature (ambient temperature), displays the insulation resistance value and the test conclusion.

3.3. Plugging and turning test

The software realizes the test of three-phase asynchronous motor plugging and shows the test conclusion. After testing the test equipment, the software obtains the data, showing the IA, IB, IC three-phase current value and its balance, plugging power.

Note: The current balance formula (MAX (ia,ib,ic)-average (ia,ib,ic))/average (Ia,ib,ic) *100% with a permissible range of not more than 3%.

3.4. No-load test

The software realizes the test of three-phase asynchronous motor no-load and shows the test conclusion. After testing the test equipment, the software obtains the data, showing the IA, IB, IC three-phase current value and its balance, no-load power. According to the standard voltage correction test results and the standard values are compared to show the test conclusion.

The specification stipulates that the test motor is applied to the rated power of the variable voltage, the voltage variation range from 125% to the rated voltage gradually reduced to no-load current minimum or unstable minimum current. Between the 125% and 60% rated voltages, which include the rated voltage, at least 5 voltage points are taken at a uniform distribution. At least 4 voltage points are taken between the rated voltage and the minimum voltage of approximately 50%.

3.5. Rotational Speed Steering test

The software realizes the test of three-phase induction motor speed steering and shows the test conclusion. The rotational speed steering test and the no-load test are being transferred simultaneously. Software according to the test data of the system, output speed steering, rotational speed test results and standard output speed range to draw conclusions, turn to the results of the system record but do not make a decision.

3.6. Oil injection control and monitoring

The software realizes the control and monitoring of the oil injection quantity of the three-phase induction motor speed steering and shows the test conclusion. Start oil injection before the operator will be the corresponding circuit and reducer to make a good connection, the system received confirmation information after the start of solenoid valve, the operator opened the oil gun, the system automatically according to the required oil injection, to achieve the set of oil injection automatically cut off the supply line, the software needs to remind operators of oil finish.

3.7. Turn-to-turn testing

Turn-to-turn testing of the motor. Pulse voltage Impulse is applied to the standard coil and the motor test coil respectively to collect and save the oscillation curves produced by each. Through the comparison between the two curves to determine the inductance between the measured coil and the standard coil, the difference between the quality factor, as well as the winding number of poor, inter-turn short circuit and other undesirable conditions.

3.8. Air tightness test

Measuring range 0~1mpa, accuracy 0.5%.

3.9. Withstand pressure test

The software realizes the voltage withstand test between the windings of the three-phase asynchronous motor and the casing (ground), and displays the test results. A voltage of 2200V between the motor winding and the housing (ground) is applied to test the leakage current between the two ends to check whether the leakage current is within the qualifying range.

3.10. Comprehensive testing

Software to achieve comprehensive testing function, according to the operator of the above 6 test functions of the main screen check box selection, the corresponding combination test, and save the results.

3.11. Manual Testing

The software implements manual testing of the inspection equipment. There is a separate manual operator interface.

3.12. Check function

Every day testing equipment need to do a point check, pop-up point check prompt box prompt inspection, short-circuit winding and ground, testing the electrical insulation test, unqualified for the spot inspection success. Every day the first thing to boot the device needs to be checked, or other motor testing can not be done. After the checkpoint is successful, enter the test main work screen.

3.13. Introduction to the integrated testing process

In general, the production line uses a comprehensive testing process for motor testing.

Belt inspection equipment can be divided into a single box, single motor, box and motor combination of several types. Different types of test items are also different, details are as follows:

? Single box: Oil injection detection, insulation resistance testing, no-load test, rotational speed test;

? Single Motor: DC resistance test, insulation resistance testing, plugging test, no-load test, rotational speed test, turn to test;

? Box Plus motor: Oil injection detection, DC resistance test, insulation resistance testing, plugging test, no-load test, rotational speed test.

The specific test item can be freely selected by the operator when the comprehensive test is actually tested.

The flowchart is as follows:

Figure 3-1 Integrated test flowchart for motor testing

4. Screen function definition

The detection screen adopts only one main screen to show the test items and test methods of the motor test. That is, the user opens the motor detection client in front of the screen, including the scanning gun barcode information, automated testing process parts, as well as the part of the step test. The software according to the input work number query analysis needs to test the equipment model, according to the model information in the database analysis of the test needs to test the content, and the unnecessary test Content text box screen.

4.1. Main interface function

The overall layout of the screen is modular, and each test item shows its test data and results by a module. The interface definition is presented to the user as a theme defined throughout the software function, as shown in Figure 4-1.

Figure 4-1 Main interface

Users use the following methods:

? When the user with the scanning gun scan click on the ticket, the ticket text box immediately shows the number of test motor, model, serial number, oil number and other content.

? The type of motor is displayed in turn.

? Unwanted test content, the corresponding test item becomes grayed out.

? Click on the "Comprehensive test" button, Pop-up Test Select Confirmation window (see 4.2. Test Selection Confirmation window), the user selects the test item here and confirms the test parameters, immediately start the automatic test, and then return to the screen for the test results and test values display, if the test is successful to upload the test results to the server, test failure is not tested.

? Click on the "Withstand pressure test" button, the system will carry out the pressure test, and the results will be displayed in the main screen of the voltage-resistant module;

? Click the "one-way Test" button, the system will be the same as the comprehensive test pop-up test item selection screen, but at this time can only select one content to test.

? Click the "Manual Test" button, pop-up manual test screen, the screen has positive and negative control, brake power selection, control, three-phase voltage, current meter monitoring, rotational speed measurement, power protection and other functions. See 4.10 manual operator interface.

? The software communicates with the remote database in the background, records the test results in the local database, and uploads the test records to the remote database.

4.2. Test Selection Confirmation window

The screen is ejected when the user selects the "Comprehensive test" button on the main interface. This screen contains:

? Information Confirmation

Parameter confirmation and modification including motor information, box information, oil injection information and serial number information;

? Test Item Settings

L 380 ext. 400: If the check box is selected, then the rated voltage of the device is 380V, then the 380V is automatically converted to 400V for testing;

L no-load judgment: check box is selected after the no-load power test results to determine, otherwise the default is qualified;

L Test Failure: When the comprehensive test encountered unqualified items, the preset option can be used to do the corresponding operation (interrupt test and prompt for re-testing, stop test or ignore (insulation test results are not allowed to ignore the case));

? Test item Selection

This area allows users to select test items that need to be tested for comprehensive testing. When comprehensive testing, the region option is multi-select, and one-way test, the region option is a single radio.

Figure 4-2 Test Selection Confirmation window

4.3. Communication parameter setting

System administrator Login permissions can be selected through the main interface "test"-"Communication parameter settings" into the Communication Parameters settings interface, which is used to set the communication port of various instruments, convenient connection and debugging equipment. "Operator" and "Administrator" have no Modify permissions. 4-3:

Figure 4-3 serial port parameter setting interface

4.4. Test Maintenance window

The user can select "test"-"Test Maintenance window" through the main interface to enter this interface. This interface is used to modify the global (Database Ratedpara table) test criteria for the specified test machine name. Operator "and" Administrator "have no Modify permissions. Please follow the example below:

Figure 4-4 Test Maintenance window

4.5. Oil Injection Speed Test window

The user can enter this interface by selecting the "Test"-"Oil injection speed Test window" from the main interface. This interface is mainly used for monthly oil injection coefficient correction and tachometer is working properly. Please follow the example below:

Figure 4-5 Oil injection Speed Test window

4.6. Work Order Information Management

The user can choose "management" through the main interface, "Ticket information management" to enter this interface, the function of this interface is convenient for the administrator to add the definition of new ticket information, query and the existence of ticket information. To facilitate the production of inspection requirements. Query and save all rely on "work number" for database retrieval, so must guarantee the uniqueness of "ticket", and "ticket" input box is required. Administrators and system administrators have Modify permissions, and operators have only query permissions. The test parameters are added as shown in Window 4-5.

Figure 4-6 Work Order Information Management window

4.7. Bug Summary Add

If the comprehensive test results are not qualified, the defect Summary screen will be automatically ejected. 4-6. After completion by the quality management personnel. Click Save, then save to the database, corresponding to the database table name "Testerrresult", add a record. When you open the interface, you need to be able to automatically populate the current serial number. After the save is successful, the interface is automatically closed.

Figure 4-7 Defect Summary Interface

4.8. Test parameter Additions

The user can choose "Manage"-"test parameter Add" through the main interface to enter this interface, the function of this interface is to facilitate the administrator to add their own definition of new test standards, these new test standards can be applied to existing equipment or new equipment detection. The test parameters are added as shown in Window 4-7.

Figure 4-8 Test Parameters Add interface

? Query: "Motor identification Code" for the query conditions, so do "query" action, the interface on the Motor Identification Code input box can not be empty.

? Modify Save: With "Motor identification code" for the query conditions for other data modification, so do "modify save" action, the interface on the Motor Identification Code input box can not be empty.

? Added Save: The "Motor information" content for the search content combination into a new "motor identification code", so the "motor information" parameters must be filled in full and correct. New Prompt Confirmation box.

? Delete: the "Motor Identification code" is the deletion condition, so this input box is required. Remove feature only system administrator has this permission.

4.9. Data query

Users can choose "experimental data" through the main interface-"data query" into this interface, the data query interface for operators to test the results of the storage and query methods to facilitate enterprise production management and records. See 4-8 for details:

Figure 4-9 Test Result Query Delete

The test can be divided into "work order", "Serial number", "Operator", "Test machine name", "all" limit conditions for the query, and can be set by the date for two-level filtering. Query function using database paging lookup mode, up to 25 records at a time to avoid query results too long, query slow problem.

4.10. Defect Summary Query

Users can choose "Experimental data"-"Bug Summary query" through the main interface to enter this interface, detailed see 4-9:

And the bug summary Add the interface face should be the same database table.

Same as the data query interface, can also be based on the work order number, serial numbers, operators, test machine name, and date for conditional query.

Figure 4-10 Defect Summary record query interface

4.11 Manual Operator interface

Manual operation can be opened manually at the main interface point. Press the Entity Start button again to make the device available. The motor brake and start stop can then be operated manually. 4-10.

4-11 Manual Operator interface

Data reference: Tianjin Tong Guang Group Digital Laboratory

Application research of three-phase asynchronous motor detection technology