Passivity-Based Control of Buck Converters with Constant-Power Loads

This paper studies the control of buck converters subjected to constant-power loads using a passivity-based technique. This technique allows for global analysis and avoids the limitations present in small-signal-based techniques. Passivity-based control in this application leads to a systematic derivation of a linear proportional-differential controller. It is also proved that the equilibrium point is only locally stable due to the infeasibility of duty ratio values larger than unity. The paper presents a method to obtain the region of attraction and shows that this region is not affected by controller gains. Experimental work is included to verify the analysis.

[1]  Mehrdad Ehsani,et al.  On the Concept of Negative Impedance Instability in the More Electric Aircraft Power Systems with Constant Power Loads , 1999 .

[2]  Ali Emadi,et al.  Dynamics and control of multi-converter DC power electronic systems , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[3]  R. Ortega,et al.  Energy-shaping of port-controlled Hamiltonian systems by interconnection , 1999, Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304).

[4]  Romeo Ortega,et al.  Passivity-based controllers for the stabilization of Dc-to-Dc Power converters , 1997, Autom..

[5]  P.T. Krein,et al.  Mitigation of power system collapse through active dynamic buffers , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[6]  R. W. Ashton,et al.  The application of feedback linearization techniques to the stabilization of DC-to-DC converters with constant power loads , 1998, ISCAS '98. Proceedings of the 1998 IEEE International Symposium on Circuits and Systems (Cat. No.98CH36187).

[7]  Robert S. Balog,et al.  Autonomous Local Control in Distributed DC Power Systems , 2006 .

[8]  F. C. Lee,et al.  Modeling, analysis and design of distributed power systems , 1989, 20th Annual IEEE Power Electronics Specialists Conference.

[9]  C. Rivetta,et al.  Large-signal analysis of a DC-DC buck power converter operating with constant power load , 2003, IECON'03. 29th Annual Conference of the IEEE Industrial Electronics Society (IEEE Cat. No.03CH37468).

[10]  Philip T. Krein,et al.  Elements of Power Electronics , 1997 .

[11]  V. Grigore,et al.  Stabilizing a telecom power supply feeding a constant power load , 1998, INTELEC - Twentieth International Telecommunications Energy Conference (Cat. No.98CH36263).

[12]  V. Grigore,et al.  Dynamics of a buck converter with a constant power load , 1998, PESC 98 Record. 29th Annual IEEE Power Electronics Specialists Conference (Cat. No.98CH36196).

[13]  R. D. Middlebrook,et al.  Input filter considerations in design and application of switching regulators. , 1976 .

[14]  M. Ehsani,et al.  Negative impedance stabilizing controls for PWM DC-DC converters using feedback linearization techniques , 2000, Collection of Technical Papers. 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) (Cat. No.00CH37022).