Rotor Position Measurement at Low Speeds

[erdemdilmen]

Hello,

I am planning to use BLDC motors in a robotic manipulator where torque control of the motors will be established. Thus, FOC SDK of STMicroelectronics will be utilized. Since the manipulator will be a parallel one, none of the motors will need to make one full revolution and they will work in low speeds as well. They will be equipped with encoder to measure the rotor position that is critical to FOC. Also, the zero position of the motors will be known prior to the running of the manipulator and so absolute position measurement will be no problem.

My question is as follows. Can BLDC motors be used in the above mentioned application utilizing the FOC SDK? As I know, sensorless estimation of rotor position requires the spped to be relatively high. However, HFI (high frquency injection) technique of STM can overcome this issue and can estimate the rotor position at low speeds and even at standstill. Only requirement is for the motor to be an interior PMSM. Then, in case of encoder, there is no such need as high speed and FOC SDK can be uitilized to control the BLDC motors in the application mentioned above where low speeds will be concerned. Please correct me if I am wrong.

Best,

Erdem

[GMA]

Hello @erdemdilmen,

Because your motor "will be equipped with encoder", the position control feature is adequate.
For more information, refer to the User Manual, position control chapter, available through Workbench tool > About > Documentations > Documentation, or see Application Note AN5464 for more details.

[erdemdilmen]

Hello GMA,

Thanks for the answer.

Best,

Erdem