论文信息 - A comparison and an improvement of two continuous-time models for current-mode control

A comparison and an improvement of two continuous-time models for current-mode control

Current-mode control can be used to control switched DC-DC power converters. This paper compares two continuous-time models for current-mode control that are made to be accurate up to half the switching frequency. The two models are the ones presented by Ridley and Tan. The closed loop frequency responses predicted by these two models are compared with results obtained from simulations of a buck converter in continuous conduction mode. The control-to-output transfer functions and the output impedances predicted by the two models agree very well with the simulation results. This is however not the case for the audio susceptibility. A new expression for the audio susceptibility is presented in this paper and is used to improve the two models.

B. Johansson

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