Generator Synchronizing issue

[hle42000]

We have a baseload gas turbine generator system. We have a Basler DECS-200 as a voltage regulator, Woodward SPM as an Auto-synchronizer, and Woodward Load Sharing Module. The utility voltage is rated at 13.8KV. As long as the utility voltage is dropping down to 13.4kv or more, the gas turbine generator had no problem synchronizing to Utility. But, when the utility voltage drops down to 13.2Kv, the generator couldn't synchronize to the utility bus. Please note that the Woodward auto synchronizer is a without matching voltage model. So, it only considers phase matching of generator and utility. Can somebody please give me some suggestions on how to solve this issue?

 

[rbulsara]

What issue? It appears that you are trying to create one.

Rafiq Bulsara

http://www.srengineersct.com

 

[ScottyUK]

You need a synchroniser which can control terminal voltage via the AVR as well as speed via the governor, or you need an operator to manually match voltages prior to sttempting sync.


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If we learn from our mistakes I'm getting a great education!

 

[GTstartup]

Let me see, you don't have a voltage matching unit and you can't auto synchronize when the voltages don't match.

My suggestion? - get a voltage matching unit

 

[catserveng]

The DECS200 has a voltage match feature, you just need to bring in the bus voltage and set it up.

 

[hle42000]

We don't have a manual synchronizing operation. Our customer only wants automatic synchronzing operation.
The Woodward SPM auto synchronizer part nunmber is 9907-028
I have talked to Woodward technical support, he said this model has without voltage matching, so it only looks for phases of generator and utility before it issues a breaker closing command.

So, you recommended to use the auto synchronizer with voltage matching circuit? Then I would like to know when do we use the model without voltage matching?

 

[dpc]

Many new voltage regulators can do voltage matching without any help from the auto synchronizer. You just need an external check that the voltage is matched before actually closing the breaker to make sure the regulator hasn't lost its mind. This can be done by a synch check relay, but you probably don't have that either.

It's not unusual to buy the synchronizer without voltage matching to save money, since the function is generally not needed. But it helps to have some idea of how a generator is synchronized to the grid.



David Castor

http://www.cvoes.com

 

[catserveng]

You have all the hardware you need, with the possible exception of a sync check relay as mentioned above. But depending on the generator protective relay you have, it may have that function. Review the DECS manual on setting up the voltage match, it's not that hard. You may want to delay the SPM run signal for a short time to allow the DECS to adjust the voltage to the desired level, then allow the SPM to match phase and issue the close command.

Mike L.