Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Updated version "Robust Voltage Regulation of DC-DC Buck Converter With ZIP Load via An Energy Shaping Control Approach"

Wei He, Yanqin Zhang, Yukai Shang, Mohammad Masoud Namazi, Wangping Zhou, Josep M. Guerrero

TL;DR

This work tackles robust voltage regulation of a buck converter feeding a ZIP load in a DC distribution network. It recasts the system as a port-Hamiltonian model and develops an adaptive energy shaping controller (AESC) augmented by a disturbance observer to handle time-varying matched and mismatched disturbances, with an explicit domain-of-attraction guarantee. Key contributions include a formal stability analysis, online disturbance reconstruction, and a comparative validation against PI and RPBC via simulations and hardware experiments. The proposed framework improves robustness and transient performance for ZIP/CPL-laden DC microgrids and offers a structured approach for energy-shaping control under uncertain loads.

Abstract

ZIP loads (the parallel combination of constant impedance loads, constant current loads and constant power loads) exist widely in power system. In order to stabilize buck converter based DC distributed system with ZIP load, an adaptive energy shaping controller (AESC) is devised in this paper. Firstly, based on the assumption that lumped disturbances are known, a full information controller is designed in the framework of the port Hamiltonian system via energy shaping technique. Besides, using mathematical deductive method, an estimation of the domain of attraction is given to ensure the strict stability. Furthermore, to eliminate the influence of parameter perturbations on the system, a disturbance observer is proposed to reconstruct the lumped disturbances and then the estimated terms are introduced to above controller to form an AESC scheme. In addition, the stability analysis of the closed-loop system is given. Lastly, the simulation and experiment results are presented for assessing the designed controller.

Updated version "Robust Voltage Regulation of DC-DC Buck Converter With ZIP Load via An Energy Shaping Control Approach"

TL;DR

This work tackles robust voltage regulation of a buck converter feeding a ZIP load in a DC distribution network. It recasts the system as a port-Hamiltonian model and develops an adaptive energy shaping controller (AESC) augmented by a disturbance observer to handle time-varying matched and mismatched disturbances, with an explicit domain-of-attraction guarantee. Key contributions include a formal stability analysis, online disturbance reconstruction, and a comparative validation against PI and RPBC via simulations and hardware experiments. The proposed framework improves robustness and transient performance for ZIP/CPL-laden DC microgrids and offers a structured approach for energy-shaping control under uncertain loads.

Abstract

ZIP loads (the parallel combination of constant impedance loads, constant current loads and constant power loads) exist widely in power system. In order to stabilize buck converter based DC distributed system with ZIP load, an adaptive energy shaping controller (AESC) is devised in this paper. Firstly, based on the assumption that lumped disturbances are known, a full information controller is designed in the framework of the port Hamiltonian system via energy shaping technique. Besides, using mathematical deductive method, an estimation of the domain of attraction is given to ensure the strict stability. Furthermore, to eliminate the influence of parameter perturbations on the system, a disturbance observer is proposed to reconstruct the lumped disturbances and then the estimated terms are introduced to above controller to form an AESC scheme. In addition, the stability analysis of the closed-loop system is given. Lastly, the simulation and experiment results are presented for assessing the designed controller.

Paper Structure

This paper contains 14 sections, 3 theorems, 27 equations, 18 figures, 2 tables.

Table of Contents

  1. Introduction
  2. Literature review
  3. Contribution
  4. System model and problem formation
  5. System model
  6. Problem formulation
  7. Adaptive ESC design and stability analysis
  8. ESC design
  9. Further discussion on sufficient condition \ref{['condition']}
  10. Adaptive ESC design
  11. Stability analysis
  12. Simulation results
  13. Experimental results
  14. Conclusion

Key Result

Proposition 1

Consider the system (system3) verifying Assumption ass1. An ESC is designed as where $k > 0$ and $\alpha > 0$ are controller gains, $x_c$ is a new state of the controller. The following condition is satisfied Then, the closed-loop system is asymptotically stable around the equilibrium $(e_1^\star, e_2^\star ,e_3^\star)=(0,0,0)$.

Figures (18)

  • Figure 1: A typical structure of DC microgrids.
  • Figure 2: A typical structure of buck converter based DC distribution system.
  • Figure 3: The control diagram of DC-DC buck converter feeding a ZIP load.
  • Figure 4: The response curves of buck converter with a ZIP load under the proposed controller with different control gains.
  • Figure 5: Output voltage curves in the case of a step change in the reference $v_*$.
  • ...and 13 more figures

Theorems & Definitions (7)

  • Proposition 1
  • Proposition 2
  • Remark 1
  • Proposition 3
  • Remark 2
  • Remark 3
  • Remark 4