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Give more info please Discribe the problem with harmonic data, voltages and system size

Find manufacturer's tables You may have to dig for “Bid Evaluations” or some other Bid generator-turbine documents. The manufacturer has to have given tables about fuel consumption. Fuel consumption is paramount to define the winning offer.

Dede61: You are right, I do agree that a capacitor bank will improve the efficiency of the generators. Do you know the PF of that company before applying Caps? Has this company poor power factor and a lot of harmonics? That company may be solving more than one problem with the Caps. Stulea, to...

In 8.5.2 states 600V and bellow As a reference you can use "Element of Power System Analysis" by Stevenson

Stulea after reading your statements, here you have my comments You know that the generators have the ability of working at leading power factor (Producing reactive power) where *The power input to the turbine regulates the most of the real power that the generator generates. *The generator...

You need a relay to prevent the generator from exporting power. The relay will operate over the speed governor and the AVR to keep the gen from exporting power. See http://www.woodward.com/ic/pdf/01740.pdf http://www.woodward.com/IC/pdf/82380.pdf No, I do not work for these people

Previous Posts from Scottf and Busbar already defined that you need to ground both sides. For IEEE recommended practice for harmonic control you may check STD519. Now, the circulation of harmonics in this application is usually not a concern because metering and relaying equipment will not...

The formula is basic, of course all these are complex numbers. d:o) V bus = V system – I motor starting x Z system ***************** The main concept here is that Z system is the impedance of the system at MCC terminals, and this value can be calculated from the short circuit current (SCC): Z...

I used "log log paper" as a filter and found the following: www.members.cox.net/mikecrivello/ Graphingonloglogpaper.doc You may copy and paste the graph in another doc, and set the size of the page where you want to print the log-log graph ...

jghrist I neglected the evaluation of the transformer because the impedance of the line was referred to 66kV voltage base. If the system has a transformer then your analysis applies. Now, the system short circuit capacity is independent of the per unit bases selected (The same value of short...

You have short circuit available at 66kV equal to 1830 MVA, and you are using power base equal to 100 MVA and voltage base 11 kV (Is this because you have a transformer? Or should be 66kV?), then You may do it without pu analysis Short circuit available (I = S / (1.732 V) System impedance will...

I have Elements of Power System Analysis by WD Stevenson- Fourth Edition, and in my opinion it is a great reference for Transmission lines System modeling Symmetrical components Unsymmetrical faults Power system stability I found that does not have good samples for load flow and for the...

I have great respect for the time that you have volunteered to answer my questions, and if I asked for advice (And your time) is because I want to make sure that I am considering all the variables to increase the rating of this cell (You may read my original thread). In my opinion, this Forum...

Check the voltages they may not be identical in magnitude and angle, because the voltages from utility are not quite balanced and the transformer is not perfect. Check the loads they may not be identical in magnitude and angle. Check the currents they may not have the same angle Beside that...

Thank you dcp, my problem is not the breaker. I need to increase the sc capacity of the buses of the new cell. This cell is to add another breaker, (the existing cells are 750MVA and all the breakers are 750MVA). I cannot use reactors because this new breaker is to energize a static var...

I have a Siemens switchgear with the nominal values of 15kV, 3000A and 750 MVA short circuit capacity at old STD C37.06-1987. There is cell available with only 500 MVA short circuit capacity (K factor 1.3)with the same nominal voltages and currents. Problem: The expected 3phase sc current is...

First the transformer is at least 35 years old. You do not want to exceed the cooling capacity of the transformer oil, and must also consider that in an old transformer you have other limitations like oil expansion (the oil is not that great any more), pressure in seals (seals are not flexible...

I am interested in information about the latest equipment available to minimize power quality problems (flicker, etc.) associated with arc furnaces at steel mills. A/We are too Is there equipment available that could correct all PQ problems for a 500MW steel mill connected at 161-kV? A/One...

When using “shunt trip” you can have the following options to know when the tripping circuit is healthy: Indication lights in parallel with tripping contacts (The light is in series with the tripping coil). Note: this also applies to the closing coil and that is one reason why you have at least...

You should understand about Per unit Symmetrical components Three phase short circuit calculation (Basic with utility impedance and neglecting utility impedance – also call infinite bus) Over current protection Overcurrent differential protection It will help understanding about Thevenin...