Adaptive Passivity-Based Control of DC-DC Boost Power Converter Supplying Constant Power and Constant Voltage Loads

This paper presents a robust passivity-based control (PBC) strategy to mitigate the instability effect of the dc-dc boost power converter supplying a constant power load (CPL) and a constant voltage load (CVL) in DC microgrid systems. The control robustness of the PBC against both line and load variation is significantly improved by adding the nonlinear disturbance observer (NDO). Using the disturbance estimation technique, this observer works in parallel with the PBC strategy to compensate the disturbances of the system through a feed-forward compensation channel. Based on the dissipation property, the PBC strategy ensures the system stability, whereas the NDO guarantees global trajectory tracking to the reference voltage during disturbances. This control strategy not only ensures large signal stability of the system, but also provides a fastest recovery performance during disturbances of the system as compared with other PBC strategies. The hardware-in-loop (HIL) and real-hardware experimental results are provided to verify the control robustness of the proposed control strategy.