Gramian based digital controller design for two-input integrated DC-DC converter

Abstract

A gramian based digital controller design is proposed for a two-input DC-DC converter suitable to draw power from two different dc sources feeding a common dc-bus is presented in this paper. The proposed converter is simple and it belongs to sixth-order family performing bucking as well as boosting features. The salient features of this converter are that both the sources either individually or simultaneously supply power to the downstream load at reduced ripple current. Although this will be performing the load management, there is considerable interaction among the control loops. The issue of control-loops interaction is investigated in this paper by applying gramian based control theory. A digital voltage-mode controller is designed for downstream dc-bus regulation while the current controller regulates the power from the weak input power source. A 24 V, 96 Watt converter performance is analyzed and compared with the experimental observations. keywords: Two input dc-dc converter, Gramian, Multi-input Converter, Synchronized trailing-edge switching.

Interaction measures in a three input integrated DC-DC converter

“…The EFRI measures are based on the controllability Gramian W c and observability Gramian W o of each subsystem of the converter, W c and W o defined as (18) satisfies equation (17). Various EFRI [8] measures are HIIA, PM and H2-norm based interactions.…”

“…The interactions of TIID converter is quantified systematically using dc-gain and gramian based measures. Thus in this paper an attempt is made to analyse the interactions of integrated converter [8][9][10][11][12][13][14][15] under parameter variations. The impact of parameter variations on quantification is shown graphically.…”

“…To construct a small-signal model at a steady-state point, assume the variables y, x, d and u of the converter model are equal to steady-state values along with some small superimposed variations change k ˆin each state variables where k = x, u, y, d 1 , d 2 and d 3 in respective variables as mentioned in(8).…”

H∞ loop-shaping of a multi-input dc-dc converter using weight function parameter optimization

“…The statement of the optimization problem is given below. The parameters 'a' and 'b' of W 1 given in equation (6) are to be optimized such that, the objective function to be minimized is given in equation (16), subjected to the constraints as given in equations (17) to (22).…”

“…Multiple sources such as conventional, renewable energy sources and hybrid energy storage systems can be integrated in a DC-DC converter to have both flexibility and reliability and thus representing a multi-input multi/single output converter (MIC) [2]. The MIC topologies have one or more variables that are primarily controlled to ensure the desired degree of system stability as well as robustness range and forms a multi-variable control system [3][4][5][6][7]. To manage the available power of multiple sources in these MIC topologies, robust controllers are specifically designed which can handle a pre-defined uncertainty at an opering point.…”