0x2011 Velocity Controller

Velocity PID Tuning (objects 2011:1...2011:4)

IMPORTANT: These values are only used in velocity control mode (not in cascaded position control)

Controller Structure

image/svg+xml τ_offset τ_con τ_ref τ Velocity Control

PID Parameter Range

The constants K_p, K_i, and K_d should be between 0 and 10 with the precision of 6-digit floating point. To find the proper values of PID constants of velocity controller the following steps are recommended:

Recommended Tuning Steps
  • Step 1. Check if all constants K_p, K_i, and K_d are set to 0. After that activate the velocity controller. By default, the integral limit of velocity controller should be set to the maximum torque of the selected motor in [mNm].
  • Step 2. Set the reference velocity to 50% of rated motor velocity [rpm].
  • Step 3. Increase K_p until the measured speed is around 70% of the reference speed. As a suggestion start with K_p equal to 0.1, and in each step increase K_p with a factor of 2. 
  • Step 4. From this step forth, step response of the system should be checked. Increase K_i step by step to increase the speed of velocity controller (as a suggestion start with K_i equal to 0.01 and in each step increase it by a factor of 2). At this point, the parameters K_p and K_i of the velocity controller are tuned. The parameter K_d of the velocity controller can be kept at its default value (0).
Name Index:Sub Type Bit Size Min Data Max Data Default Data Unit Access PDO Mapping
Controller Kp 0x2011:1 REAL 32 0 0 readwrite

The P-gain of the PID Velocity Control Loop [mNm/rpm].
Name Index:Sub Type Bit Size Min Data Max Data Default Data Unit Access PDO Mapping
Controller Ki 0x2011:2 REAL 32 0 0 readwrite

The I-gain of the PID Velocity Control Loop [mNm/(rpm*s)]
Name Index:Sub Type Bit Size Min Data Max Data Default Data Unit Access PDO Mapping
Controller Kd 0x2011:3 REAL 32 0 0 readwrite

The D-gain of the PID Velocity Control Loop [rpm*s/inc]
Name Index:Sub Type Bit Size Min Data Max Data Default Data Unit Access PDO Mapping
Controller integral limit 0x2011:4 UDINT 32 0 readwrite

Integrator limitation for anti-windup. The technique used is clamping and it prevents the integral term from accumulating above or below pre-determined bounds. Initially set to MAX (2,147,483,647 --> Integral limit DEACTIVATED), please set the maximal values for your integral limit manually.