---
# System prepended metadata

title: PID control
tags: [control, motor]

---

# PID control
###### tags: `motor` `control`

## Servo control loop
![](https://i.imgur.com/Qlai85B.png)

There are often three types of closed loop in a servo drives control. Position, Velocity, and Torque. With the current loop nested inside the velocity loop, which is nested inside the position loop. In nested systems, the response of the inner loop must be faster than the response of the outer loop, or the inner loop will have little or no effect on the outer loop. For servo control loops, the inner loop should have a bandwidth that is 5 to 10 times faster than the outer loop. In this scenario, the current loop bandwidth should be 5 to 10 times that of the velocity loop, and the velocity loop bandwidth should be 5 to 10 times that of the position loop.

https://youtu.be/qKy98Cbcltw

## Reference link
[Beginners' PID Control](http://brettbeauregard.com/blog/2011/04/improving-the-beginners-pid-introduction/)