First time here? We are a friendly community of Power Systems Engineers. Check out the FAQ!

Ask Your Question

Revision history [back]

click to hide/show revision 1
initial version

answered Sep 23 '1

perolofl gravatar image

The speed channel in PSSE is in per unit speed deviation. Nominal frequency (60 or 50 Hz) is zero pu deviation. Positive pu speed deviation means overfrequency and negative means underfrequency.

Example: 61 Hz is (61-60)/60 pu speed deviation.

When plotting, use a formula and calculate (1+spd)*60 to get the channel value in Hz.