Recent content by PMACP

nawao: I did the procedure. The card appears responding as expected. Note that the excessive reactive generation only occurs at some specific periods of the week. In fact it tends to occur at saturday near 12:00-14:00 when the voltage on the grid increases. During the rest of the time the...

Hi, nawao, I read the datasheet, and I know what you said. However, the card is regulated to cos fi control, and i need to know what happens on that situation before do some other control. On other and, davidbeach said (previous post) that is not p+ossible to control the voltage.... what you...

Hi, nawao, note that the card M50FA400A is regulated in order to control de power factor, not the reactive power directly. That is, the card trys to maintain a specific cos fi not a constant value of reactive power. So, when the voltage goes up the generated reactive power tends to increase...

nawao: The guy that isntalled the system said to me that the AVR card was set to 400 V. Also he said to me that this card only is used in order to do the excitation of the generator before the paralell. After the paralell, the AVR card doesn't any contro (He said), and only the cos fi card...

Nawao, I forguet to say that in last post. The AVR only works when the machine starts. After it is connected to the main grid, the AVR is stopped and the control is made by the cos Fi regulator. Sorry for forguet say you that. This means that the voltage is not controlled, right?

Nawao, Hi. Can you, please, explain why I can't add the values? I measured the power per phase. So, The total reactive power (for instance) should be the sum of the reactive power of each phase. Where is my mistake? Thanks

Hi, I have now some data about MV voltages: Time UAB UBC UAC 7:00 16026 16065 16126 8:00 16050 16066 16120 9:00 15837 15871 15924 10:00 15897 15913 15958 11:00 15805 15838 15912 12:00 15882 15898 15987 13:00 16018 16045 16113 14:00 15799 15829 15880 15:00 15880 15880 15978 16:00 15922 15937...

Hi: Bill: "That's an interesting question. I'll have to think about it." Thank you. I wait for your opinion. Now, can you tell me if there is some problem resulting from connecting a measurement equipment to the voltage transformers on the HV side of the power transformer. I'm thing to...

Hi again Is that possible that the generator works with symetrical active and reactive power on each phase and than the transformer presents unbalanced reactive powers on each phase? Is that a evidence of saturation? Thanks

Hi Some more interesting information in attach http://files.engineering.com/getfile.aspx?folder=ed157bbc-d68e-4841-aadf-7c6efa3a7a28&file=novo.doc

nawao: in fact I can't do it. I don't have an available transformer to do that. Note that the ancillary services current may achieve 300 A per phase. Thanks

Hi "Can you measure the primary voltages?" Yes, I have some values. I'm sending you an attach with some violtage, current and power values. As well I made some comments about the regime of operation of the generator-transformer set. "Can you disconnect the generator and measure the voltages...

Bill, Hi. thank you for your very good tips. I think some of the problems I have are in fact related to what you said. However i need some more details if you can give them to me. a) Have you some written information on that subject (some book, or a paper for example)? b)You said that I...

Hi, I have now some more data. My measuremnts show me that the reactive power that is supplied by the generator to the transformer are different on each phase. Moreover, the reactive power, at some periods, are capacitive on two phases and inductive on the other one. Between the generator...

Hi, The control cards that are installed on the generator are presented on attach. There is a A V R card and a cosfi/Var card regulated to cos fi control. I don't know until this moment the set points of the cards. Do someone recognize those control cards? How do they the control? Assume...