US 12,266,919 B2
Method for adaptively adjusting PWM duty cycle, circuit and motor driving system
Sang Wang, Wuxi (CN); Xudong Zhao, Wuxi (CN); and Zhengrui Zhang, Wuxi (CN)
Assigned to CRM ICBG ( wuxi ) Co., ltd., Jiangsu (CN)
Appl. No. 18/699,318
Filed by CRM ICBG (WUXI) CO., LTD., Wuxi (CN)
PCT Filed Jul. 29, 2022, PCT No. PCT/CN2022/108942
§ 371(c)(1), (2) Date Apr. 8, 2024,
PCT Pub. No. WO2023/071344, PCT Pub. Date May 4, 2023.
Claims priority of application No. 202111282951.9 (CN), filed on Nov. 1, 2021.
Prior Publication US 2024/0332951 A1, Oct. 3, 2024
Int. Cl. H02H 7/09 (2006.01); H02H 3/24 (2006.01); H02H 7/08 (2006.01); H02P 6/28 (2016.01); H02P 27/08 (2006.01)
CPC H02H 7/09 (2013.01) [H02H 3/243 (2013.01); H02H 7/0833 (2013.01); H02P 6/28 (2016.02); H02P 27/08 (2013.01); H02P 2205/01 (2013.01); H02P 2205/05 (2013.01); H02P 2205/07 (2013.01); H02P 2209/11 (2013.01)] 15 Claims
OG exemplary drawing
 
6. A circuit for adaptively adjusting a PWM duty cycle, for a motor driving system, comprising:
a sampling module, configured to receive a direct current bus voltage and sample the direct current bus voltage, so as to obtain sample signals of the direct current bus voltage;
a digital filtering module, connected to an output end of the sampling module, and configured to perform a low-pass filtering on the sample signals to obtain low-pass filtered signals;
an under-voltage determination module, connected to an output end of the digital filtering module, and configured to determine whether the direct current bus voltage is under-voltage based on the low-pass filtered signals;
a duty cycle calculation module, connected to the output end of the sampling module and an output end of the under-voltage determination module, and configured to calculate a new duty cycle D′ and a new amplitude corresponding to the new duty cycle D′ when the direct current bus voltage is not under-voltage; wherein the new duty cycle D′ satisfies: D′=D*A/B; wherein D denotes a duty cycle obtained from a control loop of the motor driving system, A denotes a previous sample signal of the direct current bus voltage, and B denotes a current sample signal of the direct current bus voltage;
a duty cycle determination module, connected to an output end of the duty cycle calculation module, and configured to determine whether the new duty cycle D′ is greater than 100%; and
an adjustment module, connected to the output end of the duty cycle calculation module and an output end of the duty cycle determination module, and configured to initiate a weak magnetic control when the new duty cycle D′ is greater than 100%, and apply the new amplitude to a sine wave generator when the new duty cycle D′ is less than or equal to 100%, so as to adjust a duty cycle of PWM signals through the new amplitude.