Δv/Δt-intervention control concept for improved transient response in digitally controlled boost converters

authored by

Samuel Quenzer-Hohmuth, Steffen Ritzmann, Thoralf Rosahl, Bernhard Wicht

Abstract

Boost converters suffer from a bandwidth limitation caused by the right-half-plane zero (RHPZ), which occurs in the control-to-output transfer function. In contrast, there are many applications that require superior dynamic behavior. Further, size and cost of boost converter systems can be minimized by reduced voltage deviations and fast transient responses in case of large signal load transients. The key idea of the proposed ΔV/Δt-intervention control concept is to adapt the controller output to its new steady state value immediately after a load transient by prediction from known parameters. The concept is implemented in a digital control circuit, consisting of an ASIC in a 110nm-technology and a Xilinx Spartan-6 field programmable gate array (FPGA). In a boost converter with 3.5 V input voltage, 6.3 V output voltage, 1.2 A load, and 500 kHz switching frequency, the output voltage deviations are 2.8x smaller, scaling down the output capacitor value by the same factor. The recovery times are 2.4x shorter in case of large signal load transients with the proposed concept. The control is widely applicable, as it supports constant switching frequencies and allows for duty cycle and inductor current limitations. It also shows various advantages compared to conventional control and to selected adaptive control concepts.

Organisation(s)

Mixed-Signal Circuits Section

External Organisation(s)

Robert Bosch GmbH
Reutlingen University

Type

Conference contribution

Pages

316-322

No. of pages

7

Publication date

2018

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Electrical and Electronic Engineering

Electronic version(s)

https://doi.org/10.1109/APEC.2018.8341029 (Access: Closed)