MATLAB Simulation for Dual Active Bridge DC-DC Converter
Introduction:
We delve into the implementation of an active bridge simulation using MATLAB. The active bridge serves as a crucial component for voltage regulation, utilizing high-frequency transformers to convert input voltage to a variable output voltage. Through simulation, we explore the functionality of the active bridge and its ability to track reference voltage changes.
Simulation Setup:
Active Bridge Configuration: The active bridge consists of two bridges, one on the input side and one on the output side, interconnected by a high-frequency transformer. This configuration enables bidirectional power flow and voltage transformation.
Input and Output Voltages: The input voltage is fixed at 16 volts, while the output voltage can vary between 0 and 24 volts. The primary objective is to regulate the output voltage based on reference values.
Control Logic: A proportional-integral (PI) controller is employed to regulate the output voltage. The controller compares the measured output voltage with the reference voltage and generates a phase angle signal. Phase-shifted modulation techniques are utilized to generate pulses for the active bridge switches, controlling both input and output sides.
Voltage Variation: The simulation involves changing the output voltage reference every 100 milliseconds, alternating between 24 volts and 14 volts. This variation allows us to observe the response of the active bridge system under changing load conditions.
Simulation Results:
Output Voltage Tracking: The simulation demonstrates the ability of the active bridge to track reference voltage changes effectively. Despite fluctuations in the reference voltage, the output voltage closely follows the desired trajectory, maintaining regulatory control.
Response Analysis: By observing the primary and secondary voltages, as well as load voltage and current, we can analyze the dynamic response of the active bridge system. The response aligns with the desired behavior, showcasing the efficacy of the control logic and modulation techniques.
Reference Tracking: The comparison between the reference voltage and the actual output voltage highlights the accuracy of the tracking mechanism. The active bridge successfully adjusts its operation to match the reference voltage profile, ensuring consistent performance under varying operating conditions.
Conclusion: The MATLAB simulation of the active bridge for voltage regulation underscores its effectiveness in maintaining stable output voltage levels. Through precise control and modulation techniques, the active bridge adapts to changing load conditions and tracks reference voltage changes accurately. This simulation serves as a valuable tool for understanding and optimizing the performance of active bridge systems in practical applications.