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
As a general rule, the current commanded to estimate the stator inductance (Ls) should be 10% to 20% of the rated phase current (negative current). Considering the same example as the resistance estimation, if we consider the same motor, with 4 A of rated current, the recommended current would be about -0.5A, as shown below:
#define USER_MOTOR_IND_EST_CURRENT (-0.5)
Keep in mind that the current used to estimate Ls is independent of the current used for Rs identification. Even though the general guideline for both currents is 10-20% of the rated current of the motor, if the motor required more current for Rs in order to get it through the open loop ramp, the Ls current might not need to as high since the motor is already spinning.