SPRUHJ1I January 2013 – October 2021 TMS320F2802-Q1 , TMS320F28026-Q1 , TMS320F28026F , TMS320F28027-Q1 , TMS320F28027F , TMS320F28027F-Q1 , TMS320F28052-Q1 , TMS320F28052F , TMS320F28052F-Q1 , TMS320F28052M , TMS320F28052M-Q1 , TMS320F28054-Q1 , TMS320F28054F , TMS320F28054F-Q1 , TMS320F28054M , TMS320F28054M-Q1 , TMS320F2806-Q1 , TMS320F28062-Q1 , TMS320F28062F , TMS320F28062F-Q1 , TMS320F28068F , TMS320F28068M , TMS320F28069-Q1 , TMS320F28069F , TMS320F28069F-Q1 , TMS320F28069M , TMS320F28069M-Q1
Finally, the scaling of the PI coefficients throughout this series of PI Tuning sections has been done assuming we want to represent real system values throughout the signal chain. For example, the output of the speed PI controller equals the actual input reference current in amperes for the current controller. The output of the current controller equals the actual voltage applied to the motor windings. But in many designs, the PI controller outputs are normalized to per unit scaling where a value of 1 represents the maximum value possible, and a value of -1 represents the minimum value possible. For example, a current regulator's output might be scaled in such a way that 1 corresponds to 100% PWM, and -1 corresponds to 0% PWM. In these cases, it is required to know the exact scale factor between the PI output and the actual system parameter you are controlling so that you can adjust the PI coefficients accordingly.