Transient Stability Analysis: Generator Machines Models Validation Parameter Check

The Validation page is found on the Transient Stability Analysis dialog.

Generator Machine models

Clicking the Run Validation button will run the validation and clicking the Run AutoCorrection button will modify many of the input values. In Simulator running the auto correction will permanently change your input data. Then many user assume these corrections are valid for their cases but in reality it just make the simulation run without errors but do not means the solution is correct. In order to have an idea of the correction Simulator does during AutoCorrection here is a list of the Parameter Check and corrections done to the transient stability models.

Machine Model Reactance Validation

These reactance values are specified on the d-axis and q-axis and are referred to as synchronous reactance (Xd and Xq), transient reactance (Xdp and Xqp), subtransient reactance (Xdpp and Xqpp), and leakage reactance (Xl). In order for the equations which model the machine to be numerically stable, the reactance must obey the following relationships: [Xl>Xqpp>Xqp>Xq] and [Xl>Xdpp>Xdp>Xd]. A violation of any of these relationships can cause numerical instability and also just fundamentally does not make sense. Despite this, these types of errors are very common.

When encountering models which do not obey these relationships, PowerWorld Simulator will perform the following error checking, and when using auto-correction will make the following changes to the input data.

if Xqp > Xq then Xqp = 0.8*Xq

if Xdp > Xd then Xdp = 0.8*Xd

if Xqpp > Xqp then Xqpp = 0.8*Xqp

if Xdpp > Xdp then Xdpp = 0.8*Xdp

if Xl > Xqpp then Xl = 0.8*Xqpp

if Xl > Xdpp then Xl = 0.8*Xdpp

All of the synchronous generator models that have the following parameters until stated otherwise in the model: