modelPLLFreeze
Phase-Locked Loop whose angle can be frozen
Information
The PLL calculates the frequency of the grid voltage by synchronizing the internal phase angle with measured voltage phasor. q-component of internal voltage phasor is therefore controlled to be zero.
Following relationship is used to calculate internal voltage phasor q-component:
uqPu = uiPu * cos(phi) - urPu * sin(phi);
If uqPu is zero, the internal phasor is locked with the measured phasor and rotates with the same frequency.
When the freeze input is activated (by another block, e.g. on low voltage), the internal phasor is kept constant.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Types.PerUnit | Ki | PLL integrator gain | |
| Types.PerUnit | Kp | PLL proportional gain | |
| Types.PerUnit | OmegaMaxPu | Upper frequency limit in pu (base OmegaNom) | |
| Types.PerUnit | OmegaMinPu | Lower frequency limit in pu (base OmegaNom) | |
| Types.ComplexVoltagePu | u0Pu | Start value of complex voltage at PCC in pu (base UNom) |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | omegaRefPu | Reference frequency of the system in pu (base OmegaNom) | |
| Modelica.ComplexBlocks.Interfaces.ComplexInput | uPu | Complex voltage at PCC in pu (base UNom) | |
| Modelica.Blocks.Interfaces.BooleanInput | freeze | If true, integration is frozen | |
| Modelica.Blocks.Interfaces.RealOutput | omegaPLLPu | Measured frequency in pu (base OmegaNom) | |
| Modelica.Blocks.Interfaces.RealOutput | phi | Voltage phase at PCC in rad |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Continuous.Integrator | integrator | ||
| Modelica.Blocks.Math.Add | add2 | ||
| Modelica.Blocks.Sources.RealExpression | realExpression | ||
| Modelica.Blocks.Continuous.LimIntegrator | limIntegrator | ||
| Modelica.Blocks.Math.Add | add1 | ||
| Modelica.Blocks.Math.Gain | gain | ||
| Modelica.Blocks.Logical.Switch | switch1 | ||
| Modelica.Blocks.Sources.Constant | const |