Signal Flow Graph and Block Diagram · Control Systems · GATE ECE

The block diagram of a feedback control system is shown in the figure. The overall closed-loop gain G of the system is

By performing cascading and/or summing/differencing operations using transfer function blocks G₁(s) and G₂(s), one CANNOT realize a transfer function of the form

For the signal flow graph shown in the figure, the value of $$\frac{\mathrm C\left(\mathrm s\right)}{\mathrm R\left(\mathrm s\right)}$$ is

Consider the following block diagram in the figure. The transfer function $$\frac{\mathrm C\left(\mathrm s\right)}{\mathrm R\left(\mathrm s\right)}$$ is

For the following system, When X₁(s) = 0 , the transfer function $$\frac{\mathrm Y\left(\mathrm s\right)}{{\mathrm X}_2\left(\mathrm s\right)}$$ is

The transfer function Y(s)/R(s) of the system shown is

The equivalent of the block diagram in Figure is given as

Signal flow graph is used to find

In the following block diagram, R(s) and D(s) are two inputs. The output Y(s) is expressed as Y(s) = G$$_1$$(s)R(s) + G$$_2$$(s)D(s).

G$$_1$$(s) and G$$_2$$(s) are given by

The signal flow graph for a system is given below. The transfer function $$\frac{Y(s)}{U(s)}$$ for this system is

Consider the signal flow graph shown in Figure. The gain $$\frac{x_5}{x_1}$$ is

The signal flow graph of a system is shown in figure. The transfer function $$\frac{C(s)}{R(s)}$$ of the system is

An electrical system and its signal-flow graph representations are shown in Figure (a) and (b) respectively. The values of G₂ and H, respectively are

In the signal flow graph of Fig. y/x equals

In the signal flow graph of Figure, the gain c/r will be

For the system shown in figure the transfer function $$\frac{\mathrm C\left(\mathrm s\right)}{\mathrm R\left(\mathrm s\right)}$$ is equal to

In the signal flow graph shown in fig X₂= TX₁ where T is equal to

A feedback control system is shown in figure (a) Draw the signal-flow graph that represents the system.
(b) Find the total number of loops in the graph and determine the loop-gains of all the loops.
(c) Find the number of all possible combination of non-touching loops taken two at a time.
(d) Determine the transfer function of the system using the signal-flow graph.

Draw a signal flow graph for the following set of algebraic equations: $$$\begin{array}{l}y_2=ay_1-\;gy_3\\y_3=ey_2+\;cy_4\\y_4=by_2-dy_4\end{array}$$$ Hence, find the gains $$\frac{y_2}{y_1}$$ and $$\frac{y_3}{y_1}$$.

Reduce the signal flow graph shown in fig. below, to obtain another graph which does not contain the node e₅.Also, remove any self-loop from the resulting graph.