LAUNDRY MACHINE CONTROL SYSTEM FOR LOAD IMBALANCE DETECTION AND EXTRACTION SPEED SELECTION

摘要

A control system for a laundry washing machine with a horizontal wash dru m detects load imbalance in the drum and selects a proper rotation speed for the drum in a water extraction operation. A drive controller for the motor turning the drum detects a phase angle variation in the drive voltage and dr ive current applied to the motor as an indication of the load imbalance in t he drum, and determines whether the detected load imbalance falls in one of a plurality of pre-defined load-imbalance zones. The drive controller then p rovides a signal indicating the detected imbalance zone to a machine control ler of the washing machine. The machine controller selects a proper rotation speed for the extraction operation based on the detected imbalance zone, or alternatively initiates a load-redistribution operation to reduce the load imbalance.