Comparison between P, PI, PD and PID controllers

A review on the composite controllers along with the proportional controller

Considering a unit negative feedback system, with Setpoint - R(S) ,
Output - C(S) Error signal - E(s) = R(S) - C(S) Manipulated signal - M(S) The type of controller used defines the output of the system. Here, specifically we see the following controllers alone.

Proportional ( P ) Proportional - Integrated ( PI ) Proportional - Differential ( PD ) Proportional - Integrated - Differential ( PID )

Gain in time domain

Proportional ( P ) : Screenshot%20(38) Proportional - Integrated ( PI ) : Screenshot%20(40) Proportional - Differential ( PD ) : Screenshot%20(39) Proportional - Integrated - Differential ( PID ) : Screenshot%20(44)

Gain in Frequency Domain

Proportional ( P ) : Screenshot%20(38) Proportional - Integrated ( PI ) : Screenshot%20(41) Proportional - Differential ( PD ) : Screenshot%20(42) Proportional - Integrated - Differential ( PID ) : Screenshot%20(43)

Advantages:

Proportional ( P ) : Speed controlled ( Increase gain)
Proportional - Integrated ( PI ) : Good damping, Offset is zero ( because of Integration), No steady state error Proportional - Differential ( PD ) : Maximum overshoot decreases, Rise time, settling time is reduced , Bandwidth is increased. Proportional - Integrated - Differential ( PID ) : Decreases rise time (Kp), Eliminates steady state error (Ki), Decreases overshoot and settling time ( Kd).

Disadvantages:

Proportional ( P ) : Offset issue Proportional - Integrated ( PI ) : Slow Response, Stability Proportional - Differential ( PD ) : Offset, Steady state error

System Filteration

Proportional ( P ) : Linear network ( No filteration) Proportional - Integrated ( PI ) : Low pass filter Proportional - Differential ( PD ) : High pass filter Proportional - Integrated - Differential ( PID ) : Band pass or Band reject depending on gain values

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