Abstract: A washing machine appliance and a method of operation thereof are provided for shifting between different modes such as wash, rinse, and/or spin modes. A clutch is used to shift between the different modes of operation. Alignment of the clutch, particularly the clutch teeth, is provided so as to allow for proper engagement of the clutch and motor or to properly align the clutch teeth for disengagement and locking with locking teeth carried upon e.g., a platform lock.

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 washing machine and method for detecting unbalance in a washing machine. A power filter may be calculated based on a detected load size, speed of a component of the washing machine, and/or a resonant frequency of the washing machine. An unbalanced indicator may be activated when a speed does not pass the power filter.

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: A system and method of detecting phase angle in an inverter is provided. A shunt resistor is coupled to a controller which is part of an inverter circuit and a phase angle may be directly derived from the detected voltage across the shunt resistor. The detected shunt voltage may be used to adjust the power delivery from the inverter to the load.

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 washing machine appliance and a method of operation thereof are provided for shifting between different modes such as wash, rinse, and/or spin modes. A clutch is used to shift between the different modes of operation. Alignment of the clutch, particularly the clutch teeth, is provided so as to allow for proper engagement of the clutch and motor or to properly align the clutch teeth for disengagement and locking with locking teeth carried upon e.g., a platform lock.

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: A washing machine and method for detecting unbalance in a washing machine. A power filter may be calculated based on a detected load size, speed of a component of the washing machine, and/or a resonant frequency of the washing machine. An unbalanced indicator may be activated when a speed does not pass the power filter.

Abstract: An apparatus and techniques for detecting unbalanced load in a washing machine are provided. A clothes basket containing a load of clothing and rotatable about an axis is accelerated. As the clothes basket passes a first predetermined rotational speed, one of power and torque applied to the clothes basket is limited. It is determined whether the clothes basket accelerates from the first predetermined to a second predetermined rotational speed within a predetermined time. Failure to reach the second predetermined rotational speed within the predetermined time signifies an out-of-balance condition as to the load of clothing. No resonance of the machine lies between the first and second predetermined rotational speeds. In another aspect, a similar technique can be employed, with or without limiting power or torque, wherein a resonance does lie between the first and second predetermined rotational speeds.

Abstract: A system and method of detecting phase angle in an inverter is provided. A shunt resistor is coupled to a controller which is part of an inverter circuit and a phase angle may be directly derived from the detected voltage across the shunt resistor. The detected shunt voltage may be used to adjust the power delivery from the inverter to the load.

Abstract: A method of operating a motor, the method comprising: operating a motor at a first speed; operating the motor in negative slip; imbalancing at least one phase of the motor to dissipate regeneration energy using windings of the motor; and wherein a next motor speed is decreased to a speed less than the first speed. An apparatus for carrying out the method is also presented.

Abstract: An apparatus and techniques for detecting unbalanced load in a washing machine are provided. A clothes basket containing a load of clothing and rotatable about an axis is accelerated. As the clothes basket passes a first predetermined rotational speed, one of power and torque applied to the clothes basket is limited. It is determined whether the clothes basket accelerates from the first predetermined to a second predetermined rotational speed within a predetermined time. Failure to reach the second predetermined rotational speed within the predetermined time signifies an out-of-balance condition as to the load of clothing. No resonance of the machine lies between the first and second predetermined rotational speeds. In another aspect, a similar technique can be employed, with or without limiting power or torque, wherein a resonance does lie between the first and second predetermined rotational speeds.

Abstract: A method and apparatus for measuring a size of a load in a basket that is rotatably supported is presented. The method comprises determining an acceleration energy (AE) required to accelerate the basket; determining a friction energy (FE) required to maintain a stable rotational speed of the basket; subtracting the friction energy (FE) from the acceleration energy (AE) to obtain a load inertial energy (LE); and determining a load size from the load inertial energy (LE).

Abstract: A method and apparatus for measuring a size of a load in a basket that is rotatably supported is presented. The method comprises determining an acceleration energy (AE) required to accelerate the basket; determining a friction energy (FE) required to maintain a stable rotational speed of the basket; subtracting the friction energy (FE) from the acceleration energy (AE) to obtain a load inertial energy (LE); and determining a load size from the load inertial energy (LE).

Abstract: In one embodiment of the invention, an appliance and method is provided that can determine load imbalance or out-of-balance conditions. The appliances that typically apply load imbalance detection are clothes washers. A method of imbalance detection includes identifying parameter values that fluctuate with load imbalance over a predetermined sample period and determining a target parameter value from the identified parameter values. The method further includes calculating a parameter spread of the parameter values by comparing parameter values to the target parameter value. The method further includes converting the parameter spread into a weight value that reflects an imbalance condition.

Abstract: A method and apparatus is provided for determining a measurement of a portion of a load in a basket that is rotatably supported provided, the method includes: a) determining, a dry load measurement; b) spinning, the basket that is rotatably supported in order to gradually remove the liquid from the load, wherein the liquid is removed substantially by centrifugal force on the basket that is rotatably supported; c) determining a wet load measurement, wherein the dry load measurement is less than the wet load measurement; d) comparing the dry load measurement to the wet load measurement to determine a remaining liquid measurement; and e) repeating c) and d) until the remaining liquid measurement substantially is within a predetermined percentage threshold of about 0 percent to about 50 percent of the wet load measurement.

Abstract: A washing machine is provided that includes measuring a load in a washer with a motor, the method comprising: a) accelerating a load in the washer b) providing a first input voltage and running the motor until a first speed of the motor is stable; c) providing a second input voltage, d) starting a timer, upon providing the second input voltage, and obtaining a first time measurement; e) operating the motor until the load speed responds to the second input voltage to the motor and is stable; f) stopping the timer and obtaining a second time measurement; g) calculating a time differential between the first time measurement and the second time measurement; and h) determining the load size using a load size equation and the time differential.

Abstract: A method of operating a motor, the method comprising: operating a motor at a first speed; operating the motor in negative slip; imbalancing at least one phase of the motor to dissipate regeneration energy using windings of the motor; and wherein a next motor speed is decreased to a speed less than the first speed. An apparatus for carrying out the method is also presented.