Motor fault diagnosis system and method based on current and phase identification

• Main Authors: LI FENGPING, GANG JIANHUA, PENG ZHIHUI, HUANG JIBAO, HUANG BO
• Format: Patent
• Language: Chinese; English
• Published: 29.04.2022
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

The invention discloses a motor fault diagnosis system and method based on current and phase identification. The system comprises an isolation voltage transformer VT, a voltage signal conditioning circuit, an isolation current transformer CT, a sampling resistor R, a current signal conditioning circuit and a main control chip. The method detects whether the AC motor is locked by judging the phase relation between the voltage and the current in the starting stage. When locked-rotor occurs in the operation stage, the slip ratio of the motor is changed from a certain stable value to 1 in an approximate step mode. At the moment, the current of the motor is sharply increased, and the phase between the voltage and the current rapidly jumps to a new phase value. Therefore, whether the motor has the locked-rotor fault or not can be quickly and accurately diagnosed by detecting the relation between the current, voltage and current phases of the motor and the time, and the operation safety of the alternating-current mo