High and Low Grid Frequency and Voltage

I have just three comments.

1. Eschew Obfuscation
2. CRIMINAL
3. Refer to your textbook on circuit analysis to derive the appropriate equations. Examine what will happen as ω varies 15%. If you haven't had this class....

Dear friend , when STG parallel with grid we can not change grid frequency .please check nearest sub station frequency set point at which level you have to set your STG at that set point . when you export power that time if grid tripped in high frequency your STG TRIPPED due to high frequency and your STG will be safe ok from jayesh sathwara

Ok, could somebody explain what STG does while paralleling the grid. Besides sounding cool.

I presume that STG is Steam Turbine Generator (Turbo Generator). Please go through the Operation Manual supplied by the Generator manufacturer. That gives the limits of Voltage, Frequency variation (and also the combined variation) within which the the set can operate. Normally any set would operate satisfactorily for 51Hz at rated voltage.

dear Guest Welcome to the forum If your STG is connected to Grid, and the frequency of grid go to 51 hz ( i assume you were running at 50hz), than suddenly your STG stop delivering power and receive a huge amount of reverse power, as the control of STG RPM is usually slow, the only measure you can take to save your unit is to isolate it immediatly from the grid question 2- please resubmit in different editing, I didnt understand it Regards

Reverse cannot flow from the grid till the prime movers is supplying the power. Further as long as the generator is connected to the grid, generator cannot run at speed other than that of the grid. If the grid frequency increases due to load throw off then remaining load will shared by the units connected to the grid. 51 Hz should not be a cause of concern (assuming it is a 50 Hz system).

Dear Sir, the grid freq. is 51 hz and voltage is 139 kv, can over fluxing occur. Though we reduce the loading, the grid condition is same. so I think it is not good to reduce load on monitary basis. else what to do in such condition. Pl. suggest

Dear Sir, thanks for your valuable comment.

for my question 2, the trip value for the generator is 52 Hz ( as we are running on 50 Hz) we have to pump power in to the grid though it is saturated and the turbine RPM also goes high upto 5090. If there is any fluctuation of voltage or frequency in the grid this can lead to station tripping. but we cannot isolate the STG form grid as we r exporting power in open access to the third party. so in this condition what will be the safe action.

Regards,