Source code for RCAIDE.Library.Components.Powertrain.Converters.DC_Motor
# RCAIDE/Library/Components/Propulsors/Converters/DC_Motor.py
#
#
# Created: Mar 2024, M. Clarke
# ----------------------------------------------------------------------------------------------------------------------
# IMPORT
# ----------------------------------------------------------------------------------------------------------------------
# RCAIDE imports
from .Converter import Converter
from RCAIDE.Framework.Core import Data
from RCAIDE.Library.Methods.Powertrain.Converters.Motor.append_motor_conditions import append_motor_conditions
from RCAIDE.Library.Methods.Mass_Properties.Center_of_Gravity.compute_cylinder_center_of_gravity import compute_cylinder_center_of_gravity
from RCAIDE.Library.Methods.Mass_Properties.Moment_of_Inertia.compute_cylinder_moment_of_inertia import compute_cylinder_moment_of_inertia
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# DC_Motor
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[docs]
class DC_Motor(Converter):
"""
A direct current (DC) electric motor component model for electric propulsion systems.
Attributes
----------
tag : str
Identifier for the motor. Default is 'motor'.
resistance : float
Internal electrical resistance of the motor [Ω]. Default is 0.0.
no_load_current : float
Current drawn by the motor with no mechanical load [A]. Default is 0.0.
speed_constant : float
Motor speed constant (Kv). Default is 0.0.
efficiency : float
Overall motor efficiency. Default is 1.0.
gearbox.gear_ratio : float
Ratio of output shaft speed to motor speed. Default is 1.0.
power_split_ratio : float
Ratio of power distribution when motor drives multiple loads. Default is 0.0.
design_torque : float
Design point torque output [N·m]. Default is 0.0.
interpolated_func : callable
Function for interpolating motor performance. Default is None.
Notes
-----
The DC_Motor class models a direct current electric motor's performance
characteristics. It accounts for electrical, mechanical, and thermal effects
including:
* Internal resistance losses
* No-load current losses
* Gearbox losses
* Speed-torque relationships
* Power distribution for multiple loads
**Definitions**
'Kv'
Motor velocity constant, relating voltage to unloaded motor speed
'No-load Current'
Current drawn by motor to overcome internal friction when unloaded
'Power Split Ratio'
Fraction of total power delivered to primary load in multi-load applications
See Also
--------
RCAIDE.Library.Methods.Powertrain.Converters.Motor
"""
def __defaults__(self):
"""This sets the default values for the component to function.
Assumptions:
None
Source:
N/A
Inputs:
None
Outputs:
None
Properties Used:
None
"""
self.tag = 'motor'
self.diameter = 0.0
self.length = 0.0
self.resistance = 0.0
self.no_load_current = 0.0
self.speed_constant = 0.0
self.efficiency = 1.0
self.gearbox = Data()
self.gearbox.gear_ratio = 1.0
self.design_angular_velocity = 0.0
self.design_torque = 0.0
self.design_current = 0.0
self.inverse_calculation = False
self.interpolated_func = None
[docs]
def append_operating_conditions(self,segment,energy_conditions,noise_conditions=None):
append_motor_conditions(self,segment,energy_conditions)
return
[docs]
def compute_moments_of_inertia(self,vehicle,center_of_gravity=[[0, 0, 0]]):
"""
Computes the moment of inertia tensor for the motor.
Parameters
----------
center_of_gravity : list, optional
Reference point coordinates for moment calculation, defaults to [[0, 0, 0]]
See Also
--------
RCAIDE.Library.Methods.weights.vehicle.moments_of_inertia.compute_fuselage_moment_of_inertia
Implementation of the moment of inertia calculation
"""
_ , _ = compute_cylinder_moment_of_inertia(self,outer_length=self.length,outer_radius=self.diameter/2,center_of_gravity= center_of_gravity)
return
[docs]
def compute_center_of_gravity(self,vehicle):
"""
Computes the center of gravity for the motor.
See Also
--------
RCAIDE.Library.Methods.weights.vehicle.center_of_gravity.compute_fuselage_center_of_gravity
Implementation of the center of gravity calculation
"""
_ = compute_cylinder_center_of_gravity(self, length=self.length)
return
