A disturbance observer-based technique to achieve system modeling and parameter identification of micro heater

System modeling plays an important role in accomplishing the temperature control of the micro heater existing in the polymerase chain reactor (PCR). In this paper, a lumped mechanism model for the micro heater existing in the PCR system is first constructed, where some critical model parameters including the surface heat transfer coefficient and specific heat capacity are determined through a novel identification approaches simultaneously. Then, a disturbance observer (DO) that employs the input/output signal of the micro heater only is designed to estimate the lumped uncertainties caused by model errors, model uncertainties, external disturbances, and parameter perturbations. This estimates provided by the DO is added to the preliminary mechanism model of the micro heater to further improve the model' s accuracy and reasonability. Experiments and comparisons between the mechanism model without the DO and the mechanism model with the DO are conduct to reveal the superiority of the proposed overall system modeling scheme.