US 11,656,280 B2
Device for condition monitoring and protection of rotating electrical machines, and a method thereof
Simi Valsan, Kerala (IN); and Arinjai Gupta, Bangalore (IN)
Assigned to ABB Schweiz AG, Baden (CH)
Appl. No. 17/50,850
Filed by ABB Schweiz AG, Baden (CH)
PCT Filed May 30, 2019, PCT No. PCT/IB2019/054473
§ 371(c)(1), (2) Date Oct. 27, 2020,
PCT Pub. No. WO2019/229687, PCT Pub. Date Dec. 5, 2019.
Claims priority of application No. 201841020550 (IN), filed on May 31, 2018.
Prior Publication US 2021/0072320 A1, Mar. 11, 2021
Int. Cl. G01R 31/34 (2020.01); G01R 15/18 (2006.01); G01R 19/00 (2006.01); G01R 23/15 (2006.01); H02H 5/10 (2006.01); H02H 7/08 (2006.01)
CPC G01R 31/343 (2013.01) [G01R 15/181 (2013.01); G01R 19/0092 (2013.01); G01R 23/15 (2013.01); H02H 5/10 (2013.01); H02H 7/08 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A device for condition monitoring and protection of a rotating electrical machine based on measurements of current signal obtained with a current sensor measuring the current flowing in an electrical line powering the rotating electrical machine, wherein the device is configured to operate a switch to electrically disconnect the rotating electrical machine from the electrical line based on processing of the measured current, the device comprising:
an input interface configured to receive current signal from the current sensor;
a processing unit configured to:
a) extract, using at least one wavelet filter, an approximation coefficient and a frequency band content containing information representative of a condition of a rotor bar from the measured current signal;
b) compare the extracted frequency band content with a threshold value for identifying the condition of the rotor bar in the rotating electrical machine, wherein the condition of the rotor bar includes identifying damage associated with the rotor bar;
c) provide one or more status signals based on the identified condition of the rotor bar; and
an output interface configured to provide a trip signal to the switch based on at least one status signal from the one or more status signals, for electrically disconnecting the rotating electrical machine and protecting the rotating electrical machine based on the identified condition.