Centralized PID control by decoupling of a boiler-turbine unit

Centralized multivariable control by simplified decoupling

“…As an example, Figure 3 shows the Bode plots of the irrational transfer function in (23) after removing the external time delay of three units and the stationary gain equal to -0.0038. The corresponding approximation is also shown.…”

“…K(s) works as the only block to control the different measurement signals and to reduce the interactions. In recent years, several methodologies were developed for this design [16][17][18][19][20][21][22][23].…”

“…They are preferred over more advanced controllers in practical applications unless PID controls cannot meet the specifications. Therefore, the resultant controller K(s) in several methodologies [16,21,22,23] is a multivariable PID control.…”

An extended approach of inverted decoupling

“…Nevertheless, the realizability of the decoupler elements in each configuration is always the same, independent of the selected case. For example, as shown in Table 1, for inverted decoupling of TITO processes using configuration 1-2, the pair of decoupler elements that differ from one have the following expressions: 12 21 11 22 -g -g and g g (9) INSERT HERE FIGURE 4…”

“…There are two approaches of centralized control: a pure centralized strategy [4][5][6][7][8][9] or a decoupling network combined with a diagonal decentralized controller [10][11][12][13][14]. A decentralized control system with a decoupling matrix can be designed by combining a diagonal controller C(s) with a block compensator D(s) in such a way that the controller sees the apparent process G(s)·D(s) as a set of n completely independent processes.…”