Thee peak-current-mode (PCM) control strategy is widely adopted in pulse\nwidth-modulated (PWM) DC-DC converters. However, the converters always involve a sub-harmonic\noscillating state or chaotic state if the active duty ratio is beyond a certain range. Hence, an extra\nslope signal in the inductor-current loop is used to stabilize the operation of the converter. This paper\npresents a new technique for enlarging the stable range of PCM-controlled DC-DC converters,\nin which the concept of utilizing unstable period-1 orbit (UPO-1) of DC-DC converters is proposed\nand an implementation scenario based on the parameter-perturbation method is presented. With the\nproposed technique, perturbations are introduced to the reference current of the control loop, and the\nconverters operating in a chaotic state can be tracked, and thus be stabilized to the target UPO-1.\nTherefore, the stable operating range of the converters is extended. Based on an example of a\nPCM-controlled boost converter, simulations are presented as a guide to a detailed implementation\nprocess of the proposed technique, and comparisons between the proposed technique and techniques\nin terms of ramp compensation are provided to show the differentiation in the performance of the\nconverter. Experimental results in the work confirm the effectiveness of the proposed technique.
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