Cascade connection in control system

Cascade control involves the use of two controllers with the output of the first controller providing the set point for the second controller, the feedback loop for one controller nestling inside the other (Figure 13.19). Such a system can give a improved response to disturbances.

1. What is the function of Cascade?
2. What is cascade PID control?
3. What is a cascading loop?
4. What is the difference between cascade and feedforward control?

What is the function of Cascade?

Cascade function is a Boolean function which can be implemented by a so-called cascade network. An n input cascade network is a circuit built with n-1 two-input-one-output gates (i.e., dyadic operations) such that at least one input of each gate is a network input.

What is cascade PID control?

Cascade Control is an advanced application of the PID that can improve control of systems that are subject to significant lag. Since such systems are slow to respond to disturbances their performance can suffer with each upset.

What is a cascading loop?

Cascade control is a control algorithm in which the output of one control loop provides the target for another loop, as shown in the diagram below. The ultimate goal of the cascaded loops is to control the end process.

What is the difference between cascade and feedforward control?

Feedforward is thus more specific than cascade control: it is designed to head off a particular disturbance. However, it cannot measure how well it did, nor can it respond to other disturbances, such as xd1, that might affect the controlled variable.