Power System Stabilizer Models

Supplementary Discontinuous Excitation Control

Power system stabilizers are used to enhance the damping of power system oscillations through excitation control.

Commonly used inputs to the stabilizers are:

• Shaft speed

• Terminal frequency

• Power

Power System Stabilizers are represented in PSCAD as dynamic transfer functions, and can be interfaced to synchronous machine exciters.  There are several pre-defined stabilizers available in the PSCAD Master Library.  If none of these suit your needs, equivalent stabilizer systems can be constructed by using combinations of the basic control 'building blocks' from the CSMF (Continuous System Modeling Functions) section of the PSCAD Master Library.

Supplementary Discontinuous Excitation Control

In some particular system configurations, continuous excitation control with terminal voltage and power system stabilizing regulator input signals does not ensure that the potential of the excitation system for improving system stability is fully exploited.  For these situations, discontinuous excitation control signals may be employed to enhance stability following large transient disturbances.

If desired, the user may choose to include one of three types of discontinuous excitation controllers to be included within one the above chosen stabilizers.

For further details on background theory for these stabilizer models, see PSCAD reference [4].