Optimizing Reflow Soldering Oven Temperature Control: A Mathematical Approach with First-Order Modelling and PI Controller Design

This paper presents a comprehensive analysis of the identification and control of a reflow soldering oven, with the primary goal of developing a Proportional-Integral (PI) controller to ensure precise temperature regulation and high-quality solder joints in circuit board manufacturing. The study begins by examining the generic thermal profile of a reflow soldering oven, offering insights into its temperature dynamics and control requirements. A mathematical model of the oven is derived using a first-order transfer function with transport delay, based on system response analysis. This model serves as the basis for designing and tuning the PI controller. The design process involves a systematic approach, including model validation and performance analysis under various operating conditions. The optimization of temperature control focuses on minimizing overshoot, compensating for steady-state errors, and ensuring robust responses to disturbances. Comprehensive simulations are conducted to evaluate the system's performance and stability, taking into account potential disturbances, noise, and time delays. The effectiveness of the developed PI controller is validated through comparisons with a simple Proportional (P) controller, and its accuracy is verified using the pole placement method. The results demonstrate significant improvements in temperature control, highlighting the controller's ability to precisely maintain desired thermal profiles.