Service life evaluation method for bus electrolytic capacitor of motor driver

Abstract

The invention provides a service life evaluation method for bus electrolytic capacitors of a motor driver. The method comprises the steps: testing the core temperature of each bus electrolytic capacitor of a driver and the working environment temperature by means of a temperature-sensitive technology, selecting the highest core temperature rise [Delta]T among the electrolytic capacitors, and calculating the core temperature T2 of the electrolytic capacitors when the driver is running in a condition with the upper limit environment temperature. The service life of the bus electrolytic capacitors is calculated according to the difference between the highest allowed core temperature and the T2 as well as correction coefficients of bus voltages, so the service life of the driver can be evaluated. According to the method, the influence brought by the difference between an actual temperature upper limit for a driver and a test environment temperature, the influence of bus voltage when the driver is in use and the influence of uneven temperature rises among bus electrolytic capacitors are all taken into consideration. Aspects are comprehensively considered by the method, and an evaluation result is reliable.

Description

technical field [0001] The invention relates to a method for testing and evaluating the life of an electrolytic capacitor of a motor driver bus, which is used for evaluating the life of the driver. Background technique [0002] With the advancement of automation technology and the continuous development of industrial automation, servo and frequency conversion systems are widely used in manufacturing, medical treatment, entertainment, service and other industries. The purpose is to provide accurate and fast position control, which is indispensable in the field of advanced manufacturing technology. Advanced automation equipment, its technical level and application degree are an important symbol of a country's industrial automation. [0003] With the promotion and application of servo and frequency conversion systems, the demand for their performance is getting higher and higher, including shorter positioning time, better control stability, smarter self-tuning technology, and h...

AI Technical Summary

Problems solved by technology

[0005] At present, the method for evaluating the life of the electrolytic capacitor on the drive bus, one is the ripple current test method, which calculates the life of the capacitor by testing the ambient temperature, ripple current, and actual applied voltage of the electrolytic capacitor, but the calculation process is more complicated. Poor accuracy, only suitable for initial design selection, not as a means of engineering verification

The other is the thermal resistance calculation method, which calculates the life of the capacitor through the ESR of the electrolytic capacitor and the ripple current at different frequencies. The acquisition of the key parameter ESR requires a large amount of data accumulation support, otherwise the calculation result is quite different from the actual one. The method is only suitable for the initial selection design

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