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
Many automotive pumps feature a large amount of cogging force or have a very large friction. For these applications it is important to decrease the RampTime_sec parameter. This parameter is located in the configuration structure of the SpinTAC Velocity Identify global structure. The RampTime_sec value represents the amount of time in seconds it takes to ramp the Iq reference from 0 to 1.0 PU. Decreasing this value means that Iq reference will increase more quickly during inertia identification. This ensures that the motor decelerates properly. If the motor does not properly decelerate, the inertia identification process will produce a bad result.
Figure 8-7 is the speed feedback during the inertia identification process for an automotive pump with large friction. When RampTime_sec is set to 10.0 the inertia identification process does not complete successfully. It is important to notice that the larger RampTime_sec has a delayed start to the process and the motor stops in the middle of the test. Both of these conditions cause the inertia identification to fail with the ERR_ID set to 2003. When RampTime_sec is set to 3.0, the inertia identification does not have a delayed start, and the motor does not stop during the test. Both of these conditions need to be satisfied in order for the inertia identification to complete successfully.