ConstantActuatorSimple behavioural actuator model for system simulation 
This information is part of the Modelica Standard Library maintained by the Modelica Association.
Similar to rotational DCMotors, the electromechanical energy conversion of translatory electrodynamic actuators and generators of moving coil and moving magnet type can be described with the following two converter equations:
F = c * i V_i = c * v
with electrodynamic or Lorentz force F, converter constant c, current i, induced backemf V_i and armature velocity v. The model is very similar to the wellknown behavioural model of a rotational onephase DCMachine, except that it is for translatory motion. For a moving coil actuator with a coil inside an air gap with flux density B and a total wire length l inside the magnetic field, the converter constant becomes
c = B * l.
The converter constant c as well as coil resistance R and inductance L are assumed to be known, e.g., from measurements or catalogue data. Hence this model is wellsuited for system simulation together with neighbouring subsystems, but not for actuator design, where the motor constant is to be found on base of the magnetic circuit's geometry, material properties and winding data. See PermeanceActuator for a more accurate model of this actuator that is based on a magnetic network. Due to identical connectors, both models can be used in system simulation, e.g. to simulate a stroke as demonstrated in ArmatureStroke.
k 
Value: 3.88 Type: ElectricalForceConstant (N/A) Description: Converter constant 

R 
Value: 2.86 Type: Resistance (Ω) Description: Coil resistance 
L 
Value: 0.0051 Type: Inductance (H) Description: Coil inductance at midstroke 
m_a 
Value: 0.012 Type: Mass (kg) Description: Armature mass 
c 
Value: 1e11 Type: TranslationalSpringConstant (N/m) Description: Spring stiffness between impact partners 
d 
Value: 400 Type: TranslationalDampingConstant (N·s/m) Description: Damping coefficient between impact partners 
x_min 
Value: 4e3 Type: Position (m) Description: Minimum armature position 
x_max 
Value: 4e3 Type: Position (m) Description: Maximum armature position 
p 
Type: PositivePin Description: Electrical connector 


n 
Type: NegativePin Description: Electrical connector 

flange 
Type: Flange_b Description: Flange of component 
r 
Type: Resistor Description: Coil resistance 


armature 
Type: TranslatoryArmatureAndStopper Description: Armature inertia with stoppers at end of stroke range 

l 
Type: Inductor Description: Coil inductance 

electroTranslationalConverter 
Type: TranslationalEMF 
Modelica.Magnetic.FluxTubes.Examples.MovingCoilActuator Comparison of the forcecurrent characteristics of both converter models with armature blocked at midposition 

Modelica.Magnetic.FluxTubes.Examples.MovingCoilActuator Armature stroke of both moving coil actuator models after a voltage step at time t=0 