Ideal Transformer

Symbol

Information

An ideal transformer is a theoretical electrical device that transfers electrical energy between two circuits without any losses. It follows the voltage and current transformation equations:

\[ \begin{align}\begin{aligned}V_s = \frac{V_p}{N}\\I_p = \frac{I_s}{N}\end{aligned}\end{align} \]

Where:

• \(V_p\), \(V_s\): Primary and secondary voltage (Volts)

• \(I_p\), \(I_s\): Primary and secondary current (Amperes)

• \(N\): Turns ratio (dimensionless)

An ideal transformer assumes 100% efficiency, meaning there are no power losses, no leakage inductance, and no resistance in the windings.

Ports

• p1, n1: Primary coil terminals

• p2, n2: Secondary coil terminals

Symbol description

Field	Value
Symbol.name	Transformer Ideal
Symbol.file	TransformerIdeal.sym
Symbol.directory	Basic
Symbol.referance	T
Model.name	TransformerIdeal
Model.file	TransformerIdeal.py

Model

The Ideal Transformer model implements a lossless transformer with a fixed turns ratio (N).

The voltage and current relationships are defined based on the transformation ratio, ensuring ideal energy transfer.

Attributes:

• Vp (signal): Primary voltage input, defined between nodes (p1, n1).

• Ip (signal): Primary current output, defined between nodes (p1, n1).

• Vs (signal): Secondary voltage output, defined between nodes (p2, n2).

• Is (signal): Secondary current input, defined between nodes (p2, n2).

• N (param): Turns ratio (dimensionless), default is 7.0.

Methods:

analog(): Defines the ideal transformer relationship:

\[ \begin{align}\begin{aligned}V_s = \frac{V_p}{N}\\I_p = \frac{I_s}{N}\end{aligned}\end{align} \]

from pyams.lib import model, signal, param
from pyams.lib import voltage, current

class TransformerIdeal(model):
    """
    Ideal Transformer Model
    Defines the transformation ratio for voltage and current:
    Vs = Vp / N
    Ip = Is / N
    """

    def __init__(self, p1, n1, p2, n2):
        # Signal declaration
        self.Vp = signal('in', voltage, p1, n1)
        self.Ip = signal('out', current, p1, n1)
        self.Vs = signal('out', voltage, p2, n2)
        self.Is = signal('in', current, p2, n2)

        # Parameter declaration
        self.N = param(7.0, '', 'Winding ratio')

    def analog(self):
        """Defines the voltage and current relationships of an ideal transformer."""
        self.Vs += self.Vp / self.N  # Voltage transformation equation
        self.Ip += self.Is / self.N  # Current transformation equation

Command syntax

The syntax for defining an Ideal Transformer in a PyAMS simulation:

# Import the model
from pyams.models import TransformerIdeal

# Tname: is the name of the Transformer instance
# p1, n1: Primary winding connections
# p2, n2: Secondary winding connections
Tname = TransformerIdeal(p1, n1, p2, n2)