The Motor - Fisher & Paykel AquaSmart WL26CW1 Product Information

The Motor

AquaSmart™ has a brushless DC motor, with 48 permanently magnetised ferrite poles. The
stator has 36 electrically commutated poles and is controlled by 3 hall positioning sensors. The
hall sensors provide the signal to electrically control the stator magnetic poles, via the current
limiting switching electronics. The resulting magnetic field causes the rotor to rotate. The
AquaSmart™ motor controller controls the switching sequence of electrical current to the stator.
The electrical power consumption of the motor is directly dependent on the load.
Speed range: 0 - 1000 rpm
Maximum torque: 28 Nm
AquaSmart™ Stator Curved Pole Tips
Traditional auto-washers rely on a number of mechanical items to perform the functions
required of a washing machine. For example, a gearbox for agitation, solenoids and clutches for
spin, mechanical brakes to stop the basket, and timers and switches for the wash program. The
Direct Drive technology utilised in AquaSmart™ has eliminated many of these mechanical parts,
creating a simpler and inherently more reliable drive system.
Whereas traditional auto-washer motors are usually capable of two speeds, the speed of the DC
motor is dependent on the amount of current it takes from the mains. It draws less current
when it wants to go slowly, and more when it wants to go fast, a method that allows the motor
to run at any speed. Power input (current) is dictated by the motor controller, which constantly
senses the position of the motor (via the Hall sensor) and alters the current to suit.
The motor is directly coupled to the low profile agitator via a shaft, so that when the motor
moves so does the agitator. Therefore when the motor controller senses the position of the
motor it is in fact sensing the position of the low profile agitator. This allows AquaSmart™ to
continually sense what is occurring in the wash basket and feed this information to the
computer (motor controller), which then responds appropriately, adjusting speeds, water levels
etc. The "brain" of AquaSmart™ is the result of years of wash performance testing and
thousands of loads of washing. In comparison, a traditional washer continues unchanging, no
matter what happens
.