US 11,940,473 B2
Apparatus and method for compensating for offset in switching current sensing
Sang Min Kim, Yongin-si (KR)
Assigned to HYUNDAI MOBIS CO., LTD., Seoul (KR)
Filed by HYUNDAI MOBIS Co., Ltd., Seoul (KR)
Filed on Dec. 2, 2021, as Appl. No. 17/540,645.
Claims priority of application No. 10-2020-0167073 (KR), filed on Dec. 2, 2020.
Prior Publication US 2022/0170965 A1, Jun. 2, 2022
Int. Cl. G01R 15/18 (2006.01); G01R 19/25 (2006.01); H02M 1/00 (2006.01); H02P 27/06 (2006.01)
CPC G01R 19/2506 (2013.01) [G01R 15/181 (2013.01); H02M 1/0009 (2021.05); H02P 27/06 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An apparatus for compensating for an offset in switching current sensing, the apparatus comprising:
a Rogowski coil configured to detect a switching current flowing through each of switching elements to output a differentiated value;
an integrator configured to integrate the differentiated value received from the Rogowski coil;
a reset circuit configured to apply reset signals for respective switching periods of the switching elements so that an offset integrated value is not accumulated when the integrator performs integration;
a subtractor configured to receive an output value of the integrator, to perform a phase current reconstruction function, which is a subtraction operation on the output value of the integrator, to derive a voltage value corresponding to a phase current, and to output the voltage value as a current sensing signal; and
a controller configured to receive the current sensing signal from the subtractor, to process the current sensing signal using an offset calibration software, and to compensate for an offset of the current sensing signal in real time,
wherein the reset circuit provides a reset signal to the integrator at a timing of an ON period of a pulse-width modulation (PWM) switching signal.