Application of benchmark nonlinear load in UPS power supply testing

Benchmark nonlinear load is recommended by IEC62040, China standard GB/T7260 and other standards in uninterruptible power supply (UPS) testing, but due to the configuration of non-linear loads of different UPS is tedious, it is not widely used in the daily work. In order to make the testing work of UPS with nonlinear load convenient and expand the testing range, the related research is done. In this paper, the theory and structure of the wide range automatic adjustable benchmark nonlinear load is studied, a flexible configuration scheme adaptive to the needs of work is proposed, and the nonlinear load which can be adjusted automatically is developed. Its main power circuit is composed of rectifier diode, high power resistor and capacitor, which are connected in parallel with an electronic switch to achieve the different combinations to meet the needs of different power and power factors. An embedded system is introduced to automatic configure the parameters with a phase-shifting capacitor to expand the testing range of power factor. The developed intelligent nonlinear load is applied in the calibration and test of UPS and its performance is proved. The test results show that the implementation is successful.