Abstract: A method for monitoring a linear compressor is provided. The method includes determining a velocity dependent induced voltage in a driving coil of the linear compressor, extracting a higher order harmonic from the velocity dependent induced voltage, and establishing that a piston of the linear compressor is crashing if the higher order harmonic is greater than a reference value.

Abstract: Systems and methods for safely powering an appliance user interface without external power are provided. One exemplary method includes receiving power generated by rotation of a rotor. The method further includes monitoring for the presence of a safety condition and disabling passive braking of the rotor when the safety condition is present such that the user interface of an appliance is powered. An exemplary washing machine can include a basket and a motor which includes a rotor, the motor being configured to rotate the basket by rotating the rotor. The washing machine can further include a user interface and a motor control circuit configured to drive the motor. The motor control circuit can be further configured to receive power generated by rotation of the rotor, monitor for the presence of a safety condition, and disable passive braking of the rotor when the safety condition is present.

Abstract: A method for monitoring a linear compressor is provided. The method includes determining a velocity dependent induced voltage in a driving coil of the linear compressor, extracting a higher order harmonic from the velocity dependent induced voltage, and establishing that a piston of the linear compressor is crashing if the higher order harmonic is greater than a reference value.

Abstract: An electric motor in an appliance and a method of controlling the motor to achieve speeds greater than a base speed of the motor is provided. To achieve speeds above the base speed of the motor, field weakening can be implemented by applying a field weakening angle to a phase advance angle between a desired stator flux and a rotor flux. The field weakening angle can be based on the current speed of the motor. The field weakening angle can be a fixed angle and can be determined by comparing the current speed of the motor with a predetermined threshold. In addition, the magnitude of the electrical signal applied to the motor can be adjusted during field weakening based on a desired speed of the motor where the electrical signal can be a voltage.

Abstract: Systems and methods for detecting an out of balance condition for a washing machine are disclosed. The wash basket of the washing machine is rotated at a constant predetermined rotational speed. If the washing machine has an unbalanced load, the wash tub will strike the cabinet as the basket rotates in the wash tub. The tub strikes cause the wash basket to lose momentum. The inverter drive control system causes the inverter to provide more current through the motor phases to the motor to maintain constant speed. From the value of the current, the severity of the tub strikes during a test period can be determined. An out of balance condition can be detected and measured based at least in part on the severity of the tub strikes.

Abstract: Systems and methods for safely powering an appliance user interface without external power are provided. One exemplary method includes receiving power generated by rotation of a rotor. The method further includes monitoring for the presence of a safety condition and disabling passive braking of the rotor when the safety condition is present such that the user interface of an appliance is powered. An exemplary washing machine can include a basket and a motor which includes a rotor, the motor being configured to rotate the basket by rotating the rotor. The washing machine can further include a user interface and a motor control circuit configured to drive the motor. The motor control circuit can be further configured to receive power generated by rotation of the rotor, monitor for the presence of a safety condition, and disable passive braking of the rotor when the safety condition is present.

Abstract: An electric motor in an appliance and a method of controlling the motor to achieve speeds greater than a base speed of the motor is provided. To achieve speeds above the base speed of the motor, field weakening can be implemented by applying a field weakening angle to a phase advance angle between a desired stator flux and a rotor flux. The field weakening angle can be based on the current speed of the motor. The field weakening angle can be a fixed angle and can be determined by comparing the current speed of the motor with a predetermined threshold. In addition, the magnitude of the electrical signal applied to the motor can be adjusted during field weakening based on a desired speed of the motor where the electrical signal can be a voltage.

Abstract: Systems and methods for detecting an out of balance condition for a washing machine are disclosed. The wash basket of the washing machine is rotated at a constant predetermined rotational speed. If the washing machine has an unbalanced load, the wash tub will strike the cabinet as the basket rotates in the wash tub. The tub strikes cause the wash basket to lose momentum. The inverter drive control system causes the inverter to provide more current through the motor phases to the motor to maintain constant speed. From the value of the current, the severity of the tub strikes during a test period can be determined. An out of balance condition can be detected and measured based at least in part on the severity of the tub strikes.