Which are the differences of the Soft starter model for RMS and EMT simulation?
- EMT Simulation
The model used permits the direct modification of the ignition angle (alpha).
- RMS Simulation
This model is slightly different, as the application of a soft starter does not allow a simple relation between the voltages at both nodes and the ignition angle (is dependent on the R/X ratio of the load etc.). Therefore the soft starter is modeled for RMS simulation as a simple amplification factor (Kin). The behaviour can be described as follows, which is similar to a controlled reactance: U_2 = Kin * U_1; P_1 = P_2
In case a more detailed relation between the factor alpha and the value of Kin is required, it is recommended to use a simple DSL model with alpha as input and Kin as output parameter.
Hint: The model is not symmetrical - even when this is not visualized in the symbol.