Reverse Power/Min Power

I'm not an expert in this field, but my general feeling is that you will have to increase the speed of the generator.

If the incoming generator took on load for a few minutes and then cut out on reverse/min power, one thing I would suspect is that it hadn't been used for a while, and then picked up a slug of bad fuel that slowed it down, causing it to absorb power rather than contribute its share of the total load.

Check quadrature CT connections - should not in reverse

Are you running three phase?

I would test the rotation of each power input to the synchronising panel, just to be sure.

Reverse power relay operates only when power flows in oppsite direction( Motoring action).When the generator operates O.K. in solo condition, there seems no fault in generator part. C.T. connetions( specially polarity) to be checked when connected through synchronising panel.

When the genset is run singly, the reverse power cannot take place. When you are running the generators in parallel, and if the load on a set is too small compared to its capacity, the reverse power can take place. This will also happen if the load is fluctuting and the engine governor responses are not matching. In case of a sudden load reduction,the gen set with faster governor response will shed load first and may go in reverse power.

Priyadarshan

Apparently,the set which is tripping after 2/3 minutes of synchronising is due to Motoring.The reverse power would have acted and tripped the set.

Please inform us whether this problem has cropped up recently or during initial commissioning.

If the problem cropped up on already running system then the response of the set is sluggish for load variations.this may be due to the controller or governor or fuel system

This is due to the fact that the governor of the engine is not properly responding.

In modern sets for parallel operation there will be controller which will increase or decrease the speed of the set for proper load sharing.

In your case i do not know whether any controller is fitted into the system.

In any case if the system is manual, after synchronizing the sets you have manually vary the speed of the set so that the set takes load.

If the speed:Load characters of the sets are not matching properly then also these problems will crop up

You can have problem with the voltage regulator when operating in parallel because the voltage output is the same. I sugest you instal a load in the genetator and test this alone.

But your problem may be too in the speed and synchronism control.

Send me more information that I believe I can give you some help.

Cilmo Oliveira

Did the 3 generators run together?

If it is the case, then I should say that the governors are not synchronized. Therefore, the speed is different and the one with the lower speed becomes a 'motor'. I think u simply need to look at your sync panel

Are the generators of identical make?

Govenor and avr may not be responding correctly load in sync mode but will work fine on its own, i suggest you seek specialist to look at the 2 areas

JS