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oops, got one of the links wrong, should be:- http://www.ipst.org/TechPapers/2005/IPST05_Paper038.pdf Dr K S Smith Mott-MacDonald, Power Systems Division Glasgow, Scotland.

We have worked on a number of installations were Is-limiters have been installed. The ABB tripping logic is robust as it is based on instantanous i(t), di/dt measurements. One concern is the impact of capacitor switching - this may cause a high di/dt leading to tripping of the unit. Generally...

Yes. Dr K S Smith Mott-MacDonald, Power Systems Division Glasgow, Scotland.

I'd recommend PSCAD-EMTDC for this type of calculation. www.pscad.com Dr K S Smith Mott-MacDonald, Power Systems Division Glasgow, Scotland.

As the transformer inrush current is almost wholly reactive, there will be minimal transient real power demand on the system, and consequently there will be very little generator speed/frequency variation, the governor will not have to work very hard. The key factor is voltage dip, which will...

References 2 and 3 of the following paper might be useful: http://www.ipst.org/TechPapers/2005/IPST05_Paper026.pdf Dr K S Smith Mott-MacDonald, Power Systems Division Glasgow, Scotland.

This type of calculation can be undertaken using the PSCAD-EMTDC program. See http://www.ipst.org/TechPapers/2005/IPST05_Paper026.pdf for inrush calculations for windfarms. We have also sucessfully applied this methodology to offshore interconnecions. Ken Dr K S Smith Mott-MacDonald, Power...

You might find a paper I have written on this topic useful. This will not help with your present problem, but the type of analysis described in this paper would have identified your voltage drop problem at the design stage. http://www.ipst.org/TechPapers/2005/IPST05_Paper026.pdf Ken Smith Dr...

My organisation could do the work for you (you seem to have all our competitors names) Ken Smith Mott MacDonald Power Systems Division 1 Atlantic Quay Glasgow Tele +44 (0)141 222 4613 Dr K S Smith Mott-MacDonald, Power Systems Division Glasgow, Scotland.

The leakage reactance Xl is already included in Xd, Xd', Xd", Xq, Xq", etc. The normal steady state reactance of the machine Xd, is made up of two components the leakage X1 in series with the Xd mutual Xmd, i.e Xd = X1 + Xmd. Similarly for the transient reactance Xd' = X1 + Xmd*Xf/(Xmd+Xf)...

Commutation failure does not occur in diode rectifier converters. It will not occur in thyristor converters when operating as rectifiers (the firing angle alpha is in the range 0 to 90 degrees and the real power flow is from the ac to the dc side). When a thyristor converter operates as an...

The "N-S motor" was a trade named used by Lawrence Scott and Electromotors, Norwich, UK for their variable speed commutator ac motors. These machines, built before the widespread availability of variable frequency inverters, were widely used for pumping applications in the UK and...

I have measured harmonic levels at a large aluminimum smelter and can confirm that phase shifting transformers are very effective in limiting harmonic voltage distortion on the HV side on the rectifier transformer. In an aluminium smelter potline, the dc currents supplied by each rectifier are...

In a rectifier, the hand over of load current between an incomming and outgoing diode does not occur instantanously. This is due to the inductance in the supply lines to the rectifier circuit. When the incoming device starts to conduct, the current rises from zero to the dc current value, at...

The arcing transients you have described are consistient with an transient oscillation taking place between the system inductances and capacitances. Surge arrester devices could be specified which would limit the overvoltages by absorbing some of the energy in the transient. A full EMT type...

PSCAD-EMTDC is ideal for simulating rectifier systems. It also has models of electrical machines, transmission lines, etc. Highly recommended. See http://wwww.pscad.com where you can down load a personal/evaluation edition

I have a set of parameters for an induction motor with a deep bar rotor. This includes the starting and running values of the rotor single cage equivalent circuit. Can any body advise me of a straightforward method of converting these parameters to the resistance and reactance of a double cage...