Power System Stabiliser
Power System Stabiliser
(OP)
We are purchasing 3* 35MW generators for a plant that has a load requirement of 90MW. These generators are limited by the steam consumption to overall 60MW therefore we are importing from the electrical utility 30MW. We have a 33/33 OLTC as the grid transformer.
For the generators the AVR transfer control block diagram indicated a PSS ( Power stabiliser). We are unsure whether we need this for damping of small oscillations with the grid. One scenerio we could have is one generator available producing the maximum and importing 55MW from the grid.
Do we need a PSS?
For the generators the AVR transfer control block diagram indicated a PSS ( Power stabiliser). We are unsure whether we need this for damping of small oscillations with the grid. One scenerio we could have is one generator available producing the maximum and importing 55MW from the grid.
Do we need a PSS?






RE: Power System Stabiliser
You need them not only to damp the little oscillations with the grid but above all among your machines.
Moreover you must set also the reactive power compound at a negative value to avoid the reactive power oscillations.
RE: Power System Stabiliser
RE: Power System Stabiliser
RE: Power System Stabiliser
RE: Power System Stabiliser
RE: Power System Stabiliser
GEH-6359, "Power System Stabilizer for the EX2000 Digital Exciter".
That contains a very exaustive explanation about PSS.
In particular at page 1-4:
"Inter-unit oscillations typically involve two or more
synchronous machines at a power plant or nearby power
plants in which machines swing against each other.
Inter-unit oscillations typically occur at frequencies of
1.5 to 3 Hz."
RE: Power System Stabiliser
Larger machines that use static exciters (such as the EX2000) can rapidly respond and compensate for system disturbances. Additionally a large machine can correct system disturbances with a PSS, where a smaller machine cannot.
I've worked at a facility that had nine 33 MW generators, equipped with PMG type exciters, and no PSS. There were no electrical instability issues between the machines. Hope this is of help.
RE: Power System Stabiliser