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Topics in multiple-loop regulators and current-mode programming

Middlebrook, R. D. (1987) Topics in multiple-loop regulators and current-mode programming. IEEE Transactions on Power Electronics, PE-2 (2). pp. 109-124. ISSN 0885-8993. doi:10.1109/TPEL.1987.4766345.

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Some general considerations about multiple-loop feedback are discussed, and it is concluded that incorporation of a current-programmed power stage into a "new" power stage model is both justified and useful. A new circuit-oriented model of the current feedback path is derived which augments the well-known power stage canonical circuit model. The current loop gain, though wide-band, is always stable if the conventional stabilizing ramp is employed but has a relatively small low-frequency value. Consequently, the "new" power stage is more usefully modeled by a y-parameter model in which the current loop is not explicit. Expressions for the y parameters are given that are extensions of those previously derived. Another form of the model resembles the original canonical form for duty ratio programming, and shows that current programming effectively introduces lossless series damping that separates widely the two poles of the power stage LC filter. Therefore, although current programming tends to make the power stage output behave as a current source, the control-to-output voltage transfer function exhibits, in addition to the familiar dominant pole, a second pole at the current loop gain crossover frequency, which may lie anywhere from one-sixth to two-thirds of the switching frequency.

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Additional Information:© 1985 IEEE. Date of Publication: April 1987; Date of Current Version: 27 January 2009; Issue Date: April 1987. This work was conducted under the Power Electronics Program supported by grants from the General Telephone Company and Emerson Electric Company, and under contracts from IBM Tucson and San Jose, and the McDonnell Douglas Astronautics Company.
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General Telephone CompanyUNSPECIFIED
Emerson Electric CompanyUNSPECIFIED
McDonnell Douglas AstronauticsUNSPECIFIED
Issue or Number:2
Record Number:CaltechAUTHORS:20150630-134313858
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Official Citation:Middlebrook, R.D., "Topics in Multiple-Loop Regulators and Current-Mode Programming," Power Electronics, IEEE Transactions on , vol.PE-2, no.2, pp.109,124, April 1987 doi: 10.1109/TPEL.1987.4766345 URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:58712
Deposited On:01 Jul 2015 15:27
Last Modified:10 Nov 2021 22:09

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