Appliance and method for operation using fluid level detection by pattern recognition of motor current

An appliance, the appliance comprising:

• a cabinet forming a wash chamber, the wash chamber configured to contain a volume of fluid;
• a pump configured to flow the fluid to or from the wash chamber;
• a flow nozzle configured to eject the fluid into the wash chamber, the flow nozzle in fluid communication with the pump to receive the fluid therefrom;
• and
• a motor operably coupled to the pump, wherein the motor is configured to energize the pump to selectively flow the fluid through the flow nozzle;
• a controller operably coupled to the motor, the controller configured to perform operations, the operations comprising:
• acquiring a dataset comprising a function of current magnitude and time corresponding to operation of the pump to flow the volume of fluid;
• determining an average current magnitude based at least on the dataset;
• determining a standard deviation based at least on the average current magnitude;
• comparing the standard deviation to a threshold to determine whether to transmit a control command to the motor;
• and
• transmitting the control command to the motor when the standard deviation is greater than the threshold, wherein the control command is a stop fluid fill signal corresponding to ending fluid input to the wash chamber, a start fluid fill signal corresponding to providing fluid to the wash chamber, or a pump speed change signal corresponding to adjusting operation of the pump.