Hamilton Sundstrand Company ACT2000 User Manual

Page of 45
 ACT2000
 
 
1.4  Brushless DC Motor Assembly 
A brushless DC motor powers the ACT2000 linear drive mechanism. The DC 
motor contains a stator and rotor. See Figure 1-3 
Motor Stator 
The motor stator is attached to the main housing by a pre-loaded wave spring 
and screws. Thermistors are embedded in the stator windings to monitor winding 
temperatures. The motor electrical power and thermistor wires pass from the 
motor through a conduit into the electronics housing. 
Motor Rotor 
The motor rotor is locked to the ball screw shaft via a straight key. The motor rotor 
contains powerful magnets that align with the energized stator windings thereby 
creating torque and shaft rotation. 
1.5  Motor Control Electronics 
The motor control electronics (MCE) are contained within the main housing 
electronics enclosure. The MCE includes harnesses, heat sink, digital and driver 
component assemblies (CA). 
The MCE electronics communicate with the user’s controller through analog and 
serial interfaces. The MCE controls the brushless DC motor, to position the 
actuator based on position feedback from the resolver. 
Note:
 The digital board analog and discrete interfaces are electrically 
isolated. The MCE serial interface is NOT electrically isolated. 
 
1.6 Resolver Assembly 
A Brushless, non-contacting resolver is the primary ACT2000 feedback sensor.  
A sinusoidal feedback signal is provided from the resolver to the motor control 
electronics.  A sinusoidal signal from the MCE provides the resolver excitation. 
The resolver includes a stator and rotor. See Figure 1-3 
Resolver Stator 
The resolver stator is clamped to the main housing between the main bearing 
retaining nut and resolver retainer. The resolver stator angular position relative to 
the rotor is adjustable. Electrical wires from the resolver are reeled in the resolver 
adapter to allow rotation. The resolver wires, along with the motor and thermistor 
leads, are routed through a conduit into the electronics housing.  
Resolver Rotor 
The resolver rotor is mounted by a key to a ball screw shaft. As the rotor rotates, 
the stator transformer output signal provides shaft rotation information to the 
MCE. 
 
 
1-3