Design and Implementation of a Three-phase Asynchronous Motor Intelligent Test System

Abstract

Background: The locomotive traction motor has gradually shifted from DC motors to AC motors in high-speed railways, and the traction motor needs to be regularly maintained and tested frequently. Objective: The aim of this study was to test the related motor performance by obtaining and analyzing motor data from the test according to the standard "Three-phase Asynchronous Motor Test Method (GB-T 1032-2012)". The performance of the tested motor has been evaluated to meet the relevant requirements of the application. Thus, reasonable and scientific references have been offered for the maintenance and repair of the motor. Methods: A three-phase AC asynchronous motor test system based on LabVIEW and an AC power dynamometer was constructed based on the needs of the factory and type test of a three-phase AC asynchronous motor. Ambient temperature measurement, insulation resistance measurement, DC resistance measurement, no-load characteristics test, overspeed test, blocking characteristics test, load test, and temperature rise test have been carried out. The data on voltage, current, speed, power, and so on, have been collected. A 125 kW three-phase asynchronous motor was tested with the designed system, and the parameters obtained from the system were compared with those from the motor labels. Results: The three-phase AC asynchronous motor test system was designed based on LabVIEW and AC dynamometer operating on an industrial computer with a precision measuring instrument. The most advanced virtual instrument technology was used to combine the powerful data computing and processing ability with the measurement and control ability of instrument hardware. The software proved to be able to acquire data display, control, storage, and analysis simultaneously. In addition, a high degree of intelligence, an automatic motor start and stop control, automatic synchronous acquisition of test data, automatic data processing and calculation, and automatic test report generation and printing function were covered in this system. The simulated results of the system agreed well with the actual performance of the three-phase asynchronous motor, and helped the motor to operate well. Conclusion: The designed testing system exhibited a high automation ability, reliability, and accuracy. It proved to be a time and manpower-saving technical method, improving the actual test efficiency, and helped to reduce labor intensity dramatically.