US 12,438,493 B2
System and method for torque limiting of DC machines
Md Abid Hossain, Saginaw, MI (US); Ashish Verma, Saginaw, MI (US); and Thomas J. Stutts, Midland, MI (US)
Assigned to Steering Solutions IP Holding Corporation, Saginaw, MI (US)
Filed by Steering Solutions IP Holding Corporation, Saginaw, MI (US)
Filed on Nov. 21, 2023, as Appl. No. 18/515,802.
Prior Publication US 2025/0167719 A1, May 22, 2025
Int. Cl. H02P 29/032 (2016.01); B62D 5/04 (2006.01)
CPC H02P 29/032 (2016.02) [B62D 5/0409 (2013.01); B62D 5/046 (2013.01)] 20 Claims
OG exemplary drawing
 
11. A motor control system, comprising:
a brushed direct current (DC) motor having a set of brushes;
a voltage regulator configured to apply a DC voltage to the brushed DC motor based on a voltage command; and
a controller configured to:
determine, based on one of a motor current command or an actual motor current, a brush voltage drop across the set of brushes of the brushed DC motor;
determine, based on the brush voltage drop, at least one of: a first torque limit based on a supply current value not exceeding a supply current limit, and a second torque limit based on a controller supply voltage value not exceeding a maximum available voltage;
determine a final torque limit based on the at least one of the first torque limit and the second torque limit;
determine a limited torque command based on a torque command and not to exceed the final torque limit;
determine a voltage command based on the limited torque command; and
transmit the voltage command to the voltage regulator.