Simulink Modeling of Buck DC-DC Converter with Voltage and Current Feedback Control

This article presents a Simulink-based modeling approach for Buck DC-DC converters incorporating both voltage feedback and current feedback control systems. The Buck converter, a fundamental power electronics device, efficiently steps down DC input voltage to a lower regulated DC output level. Simulink modeling provides an effective platform for simulating and analyzing the converter's operational principles through built-in power electronics components like MOSFET switches, inductors, capacitors, and pulse-width modulation (PWM) generators. The voltage feedback loop typically employs a PID controller that compares the actual output voltage with a reference value, adjusting the duty cycle of the PWM signal to maintain stable output. The current feedback mechanism monitors inductor current using current sensors, implementing protection features like overcurrent limit and current-mode control for improved dynamic response. These dual-feedback systems are configured using Simulink's control system toolbox blocks, including subtractors for error calculation, compensator blocks for loop stabilization, and scope blocks for waveform visualization. Through Simulink modeling, engineers can simulate various operating conditions, test different control algorithms, and optimize component values using parameter sweeping techniques. The model enables analysis of transient responses, efficiency calculations, and stability verification through Bode plots and step response tests. This modeling methodology proves essential for designing and optimizing high-performance Buck converters with precise voltage regulation and robust current protection capabilities.