modelFrequencyCalc
Frequency deviation calculation from a rotating phasor
Information
This block uses the real and imaginary components of a Cartesian representation of a voltage phasor to estimate the electrical frequency deviation from nominal value present at the node.
Vr*der(Vi) - Vi*der(Vr)
f = -----------------------
Vr^2 + Vi^2
The calculations are done using the filtered derivative of the real and imaginary parts of the phasor representation. The user is required to set proper values for initialization of the calculations, together with a smoothing filter time constant, used to filter the derivative components.
Note
The calculated frequency is just an estimate and can deviate by a certain margin of error.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | start_guess | false | |
| Real | real_start | 1 | Phasor initial real part |
| Real | imag_start | 0 | Phasor initial imaginary part |
| Types.Time | Ts | 0.01 | Smoothing filter time constant |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | real_part | ||
| Modelica.Blocks.Interfaces.RealOutput | y | O/P is in rad/sec | |
| Modelica.Blocks.Interfaces.RealInput | imag_part |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Continuous.Der | derOfReal | ||
| Modelica.Blocks.Math.Product | ImagXderReal | ||
| Modelica.Blocks.Math.Add | diff | ||
| Modelica.Blocks.Math.Division | division | ||
| Modelica.Blocks.Math.Product | RealXderImag | ||
| Modelica.Blocks.Math.Product | imag2 | ||
| Modelica.Blocks.Math.Product | real2 | ||
| Modelica.Blocks.Math.Add | sum | ||
| Modelica.Blocks.Continuous.Der | derOfImag |