Platinum Resistance High-Precision Nonlinear Correction Based on Genetic Algorithm

Main reasons why nonlinear errors exist in the process of temperature measurements with platinum resistors have been analyzed in accordance with the nonlinear characteristic of platinum resistors. Then, the principle of two nonlinear compensation algorithms, such as Genetic algorithm, Newton iteration method is introduced. At last, measuring data based on single-chip computer temperature measurement and control system are used as samples, and the compensation error of these algorithms are analyzed and compared with the help of MATLAB under the condition of the different curve fitting order and strategy. The results show that, as for the accuracy of measurement, sub-fitting is higher than that of the whole and the high-order is higher than that of low-order on the same compensation algorithm conditions; genetic algorithm combined with the Newton iteration method is superior to genetic algorithm on the same curve fitting conditions.