SLAU927B June 2024 – November 2024 MSPM0G3507
To estimate the rotor position accurately, the motor needs to build sufficient BEMF before switching to closed loop. During startup, the FOC algorithm accelerates the motor with a second order open loop ramp profile to increase the speed until sufficient BEMF is built. By default, for basic spin up of motor, the open loop ramp up parameters are configured with a linear first order configuration with sluggish acceleration, which works for most of the motors. Disable switching to closed loop control to verify the appropriate functionality of open loop , using closedloopDis = 1b in ALGO_DEBUG_CTRL on the Motor Tuning page. To further optimize the startup time, see Section 7 to fine tune the startup performance.
Depending on the load of the motor, tune the OL_ILIMIT to the lowest possible value for smooth handoff once the closed loop is enabled (closedloopDis = 0b).