Nonlinear control of switched-capacitor converter using sliding mode control approach

Conventional PWM voltage mode or current mode control techniques are commonly used in practice for controlling switched-capacitor converters. However, such control methods are only useful for applications involving small operating regions. This paper discusses the application of nonlinear control in the form of sliding mode control on switched-capacitor converters. The result is an enlarged operating range and hence wider application possibilities. The sliding mode controller adopted in this work is of constant-frequency type that is derived from the indirect sliding mode control technique. The design, analysis, and implementation issues of this controller are detailed in the paper. Experimental results are presented to validate the theoretical design and to illustrate the strength of the proposed controller.