https://ww1.microchip.com/downloads/en/appnotes/01078b.pdf
https://www.infineon.com/dgdl/Infineon-TLE987x-Sensorless-Field-Oriented-Control-ApplicationNotes-v01_00-EN.pdf?fileId=5546d46270c4f93e0170f23529817afa
https://www.infineon.com/dgdl/Infineon-AN93637_PSoC_4_Sensorless_Field_Oriented_Control_(FOC)-ApplicationNotes-v05_00-EN.pdf?fileId=8ac78c8c7cdc391c017d0740371063ac
ODRIVE PLL
https://github.com/odriverobotics/ODrive/blob/f04c36538a0b02e7ffefaabf3dfc6a1a188411ed/Firmware/MotorControl/sensorless_estimator.cpp
https://cas.mines-paristech.fr/~praly/Telechargement/Journaux/2010-IEEE_TPEL-Lee-Hong-Nam-Ortega-Praly-Astolfi.pdf
Greqt blog
https://imperix.com/doc/implementation/sensorless-motor-control
https://imperix.com/doc/help/using-the-angle-decoder-modules
Papers overview
https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/iet-pel.2019.0822
10.35860-iarej.412250-774131.pdf
An_improved_Q-PLL_to_overcome_the_speed_reversal_problems_in_sensorless_PMSM_drive.pdf
Conventional_Synchronous_Reference_Frame_Phase-Locked_Loop_is_an_Adaptive_Complex_Filter.pdf