Induction motor temperature measurement using phase controlled alternating current

• Main Authors: Suel, II Richard Dean, Didat Mark Anthony, Gelber Scott Michael
• Format: Patent
• Language: English
• Published: 27.02.2018
• Subjects: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS,e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USERAPPLICATIONS; CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERATION; LAUNDERING; LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILEARTICLES; MEASURING; MEASURING QUANTITY OF HEAT; MEASURING TEMPERATURE; PHYSICS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TESTING; TEXTILES; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR; TREATMENT OF TEXTILES OR THE LIKE

Methods and systems are provided for monitoring current flow in an induction motor, particularly an induction motor associated with a washing machine and for controlling operation of the motor to limit thermals during operation of the motor. The subject matter provides for periodically stopping the motor and applying a phase limited alternating (AC) voltage to the motor that is of insufficient magnitude to start the motor rotating. A current reading is taken and converted using a look up table to a corresponding temperature. If the temperature exceeds a predetermined amount, temperature fold back procedures are initiated the may include shortening and/or pausing certain washer operations.