Deadbeat Controller
Not all applications will need a PID control. Some simple applications such as conveyor belt and bottle filling in the industry sometimes almost open x x the amount of time and close the output. They are called deadbeat controls, which are the oldest of all digital controls, and work well with a small operating range while sacrificing the opportunity to correct themselves in the event of unexpected errors. In the real-time control theory, the dead beat control problem involves determining which input signal should be used in the system to bring the output to a stable state with a small number of time steps.
Dead beat controllers are often used to control the process because of their good flexible properties. They are the old feedback loop where control benefits are set using a plant-based system and normal natural frequency. The deadbeat response has the following characteristics:
1. Zero steady-state error
2. Minimum rise time
3. Minimum settling time
4. Less than 2% overshoot/undershoot
5. Very high control signal output
Deadbeat controller’s algorithm
The algorithm of a deadbeat controller is in the following form:
These
terms are output feedback values and
are error feedback values. All of them are scaled by a series of coefficients which are calculated by the designer.
The general strategy for finding the algorithm is as follow:
1. Find the controller’s output (digitized)
2. Find the controller’s input (digitized)
3. Use z-transform to find the algorithm
The designer should have in his or her mind an idea of the overall system output c(t) and work from there. With the desired output signal chosen and the process’s step response known, it is possible to determine what kind of input signal must be fed into the process. The process’s input signal is also the controller’s output signal.
The designer should also know what kind of reference signal r(t) he or she will be feeding into the overall system. This knowledge, along with the knowledge of the system’s output c(t), will allow the designer to calculate the error signal. The error signal is also the controller’s input.
