US 11,705,834 B2
Sensorless angle estimation for trapezoidal control
Rajan Lakshmi Narasimha, Dallas, TX (US); and David Patrick Magee, Allen, TX (US)
Assigned to Texas Instruments Incorporated, Dallas, TX (US)
Filed by TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US)
Filed on Dec. 27, 2019, as Appl. No. 16/728,664.
Prior Publication US 2021/0203257 A1, Jul. 1, 2021
Int. Cl. H03K 5/00 (2006.01); H02P 6/15 (2016.01); H02P 6/20 (2016.01)
CPC H02P 6/157 (2016.02) [H02P 6/20 (2013.01); H02P 2209/03 (2013.01); H02P 2209/07 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
obtaining measurements of voltage signals and of a total current signal from a brushless direct-current (BLDC) motor having a rotor;
determining, with processing circuitry, an angular position of the rotor or a commutation state of the motor according to a nonlinear motor model responsive to the measurements, in which the nonlinear motor model provides using a look-up table (LUT) of voltage offsets and at least one of the following as a function of current level and current slope: voltage thresholds, or zero-crossing time intervals, the determining further including
determining a floating gate voltage with respect to a neutral voltage,
determining an offset based on the total current signal and the voltage offsets of the LUT, and
adding the determined offset to the determined floating gate voltage; and
controlling, responsive to the determined angular position or the determined commutation state, the motor during a startup of the motor.