7.1 Continuous feedback control systems and their performance
Consider a SISO electromechanical linear dynamic system, described by transfer function \(G_P(s)\), conventionally called the plant. For example, the plant might be a DC motor and mechanical load. Our goal is to continuously control its output motion by manipulating its electrical input. Applying the concept of feedback, figure 7.1 shows a block diagram of the control strategy.
Sensor \(H_S\) converts physical motion \(Y\) into an analog or digital signal appropriate to be an input to a control device through one of its interfaces. An estimate of \(Y\) is made by multiplying the detected sensor output by the inverse of the sensor DC gain \(H_{S0} = H_S(0)\) (the sensor sensitivity). The control device subtracts the …