Title:
DIAGNOSING METHOD OF MOTOR
Document Type and Number:
Japanese Patent JPS60109742
Kind Code:
A
Abstract:
PURPOSE:To readily detect the short circuit or the slack of a winding by obtaining an unbalance of phases from the maximum and minimum phase differences of the waveforms of currents of the respective phases of a 3-phase motor and an unbalance of amplitudes from the maximum and minimum amplitudes of the current. CONSTITUTION:Current transformers (CT) 2a, 2b are inserted to the phases B and C of a 3-phase induction motor, the output currents are A/D-coverted by a signal processor 3, calculated by a calculator 4, and waveform data Ad-Cd are stored for more than one period. The calculator 4 obtains zero crossing points Pa-Pc of the currents of the phases A-C to obtain the time intervals, the maximum and minimum phase differences MaxR, MinR are decided from the phases A1=Pb-Pa, B1=Pc-Pb, C1=Pa-Pc, and the phase unbalance rate UBP=(MaxR-MinR)X100% is obtained. The peak values Aa, Ba, Ca are selected from the Ad-Cd, the maximum MaxA and the minimum MinA are obtained, the average value Am=(Aa+Ba+Ca)/3 is calculated, the amplitude unbalance rate UBA=(MaxA-Min)/Am% is obtained, printed by a printer 5, thereby detecting the malfunction of the winding.
Inventors:
KUNO TSUTOMU
Application Number:
JP21576283A
Publication Date:
June 15, 1985
Filing Date:
November 15, 1983
Export Citation:
Assignee:
SUMITOMO METAL IND
International Classes:
G01R31/34; H02K11/00; (IPC1-7): G01R31/34; H02K11/00
Attorney, Agent or Firm:
Tono Kono