fluctuation compensation

YANG Lei，YIN Rong-sen

（College of Electrical Engineering，Zhejiang University，Hangzhou 310027，China）

Abstract：In order to eliminate the weighing errors caused by external supply voltage fluctuation of the weighing sensor，the method for detecting and compensating the voltage fluctuation of the weighing system was focused on. The strain effect of strain gauge and the measurement principle of the Wheatstone bridge were analyzed. Then the correcting relationship between the output voltage signal and external supply voltage signal was given. A dynamic voltage fluctuation compensation method by synchronously sampling output voltage and supply voltage was proposed subsequently. A weighing system based on digital signal processor TMS320F28335 and analog-digital

conversion chip ADS1234 was designed to examine the proposed method. The results indicate that the weighing errors of the compensated weighing system are lower than 1% within the fluctuation range of the external supply voltage，which verifies that this method is feasible for improving the weighing accuracy.

Key words：weighing；voltage fluctuation；dynamic compensation；pressure sensor；signal sample