FourBusLimits Validation

This study uses the reusable FourBusLimits case.

A fault at bus 4 from 1.0 to 1.15 s is followed by opening branch 1–4 at 2.0 s, which leaves the charged branch 2–4 open at bus 4 and raises the plant and machine voltages. Together, the two events drive these limits:

REPCA saturates at Qmax during the fault and at Qmin after the opening.
REECB limits the REPCA voltage reference to Vmax during the fault.
REGCA holds the plant voltage at Vhvmax after the opening.
ESDC1A holds the field voltage at zero after the opening.

The monitored variables are compared against reference/FourBusLimits.ref.csv, generated with PowerWorld 24.

Monitored variables