Main Content

Machine Parameterization

In Simscape™ Electrical™ software, induction machines are parameterized using fundamental parameters. Each synchronous machine is parameterized using standard or fundamental parameters.

Machine fundamental parameters include the values of inductances and resistances of the stator and rotor d- and q-axis equivalent circuits. These parameters fully specify the electrical characteristics of the machine, but you cannot determine them directly from machine test responses. Hence, it is more common to parameterize a synchronous machine using a standard parameter set. You can obtain the standard parameters by observing responses at the machine terminals with suitable tests scenarios.

You can tell the parameter set a block uses because the block name includes the parameter set name, e.g. Induction Machine Squirrel Cage. The parameters you can set in the block dialog box correspond to the parameterization type.

If a machine block has standard and fundamental variants, base your block choice on the parameters you are most familiar with or you have available. Standard block variants use classical equations to convert standard parameter values that you enter to fundamental parameter values for use at run time.

If a machine block has an SI and a per-unit variant, base your block choice on the parameters you have available. For machine blocks that are SI variants, you enter the number of pole pairs and the SI values for the nominal voltage, power, and frequency on the main tab of the dialog box. You also enter SI values for the resistance and reactance parameters on the impedance tab, and for the magnetic flux linkage parameters on the initial condition tab. The block uses classical equations to calculate per-unit base values from the parameters on the main tab. It expresses the resistance, inductance, and magnetic flux linkage parameters as per-unit ratios of the SI values (resistance, reactance, and magnetic flux linkage) and the base values for use at run time.

The field circuit and rotational ports of machine blocks use SI units. However, the pu measurement port of machine blocks outputs a vector of physical signals in per-unit.

Related Topics