## Per-Unit Conversion for Machine Parameters

### Impedance Conversion Equations

For machine impedance parameters (resistance, inductance, and reactance), the relationships between SI and per-unit values are defined by these equations:

`$R=\frac{{R}_{\left(SI\right)}}{{R}_{base}}$`

`$L=X=\frac{{X}_{\left(SI\right)}}{{X}_{base}}$`

where:

• R(SI) is the resistance, expressed in Ω.

• Rbase is the per-unit base resistance, expressed in Ω.

• R is the per-unit resistance.

• X(SI) is the reactance, expressed in Ω.

• Xbase is the per-unit base reactance, expressed in Ω.

• X is the per-unit reactance.

• L is the per-unit inductance.

### Magnetic Flux Linkage Conversion Equations

For machine magnetic flux linkage parameters, the relationship between SI and per-unit values is defined by

`$\psi =\frac{{\psi }_{\left(SI\right)}}{{\psi }_{base}}$`

where:

• ψ(SI) is the magnetic flux linkage, expressed in Wb.

• ψbase is the per-unit base magnetic flux linkage, expressed in Wb.

• ψ is the per-unit magnetic flux linkage.