Source code for pybamm.models.submodels.equivalent_circuit_elements.rc_element
import pybamm
[docs]
class RCElement(pybamm.BaseSubModel):
"""
Parallel Resistor-Capacitor (RC) element for
equivalent circuits.
Parameters
----------
param : parameter class
The parameters to use for this submodel
element_number: int
The number of the element (i.e. whether it
is the first, second, third, etc. element)
options : dict, optional
A dictionary of options to be passed to the model.
"""
def __init__(self, param, element_number, options=None):
super().__init__(param)
self.element_number = element_number
self.model_options = options
[docs]
def get_fundamental_variables(self):
vrc = pybamm.Variable(f"Element-{self.element_number} overpotential [V]")
variables = {f"Element-{self.element_number} overpotential [V]": vrc}
return variables
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def get_coupled_variables(self, variables):
T_cell = variables["Cell temperature [degC]"]
current = variables["Current [A]"]
soc = variables["SoC"]
r = self.param.rcr_element(
f"R{self.element_number} [Ohm]", T_cell, current, soc
)
c = self.param.rcr_element(f"C{self.element_number} [F]", T_cell, current, soc)
tau = r * c
vrc = variables[f"Element-{self.element_number} overpotential [V]"]
Q_irr = -current * vrc
variables.update(
{
f"R{self.element_number} [Ohm]": r,
f"C{self.element_number} [F]": c,
f"tau{self.element_number} [s]": tau,
f"Element-{self.element_number} "
+ "irreversible heat generation [W]": Q_irr,
}
)
return variables
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def set_rhs(self, variables):
vrc = variables[f"Element-{self.element_number} overpotential [V]"]
current = variables["Current [A]"]
r = variables[f"R{self.element_number} [Ohm]"]
tau = variables[f"tau{self.element_number} [s]"]
self.rhs = {
vrc: -vrc / (tau) - current * r / tau,
}
[docs]
def set_initial_conditions(self, variables):
vrc = variables[f"Element-{self.element_number} overpotential [V]"]
self.initial_conditions = {
vrc: self.param.initial_rc_overpotential(self.element_number)
}
