I am told that when a DG set is feeding non-linear loads with high distortion levels its loading or rating needs to be derated. Can somebody advise me how to calculate the derating factor, if THD(I) and THD(v) levels are known. What is the effect of Harmonics on DG set ? ARe there any articles...
We are working on design of a filter to filter out 3rd harmonics generated by SMPS of computers. However, when we conducted a log on the input parameters of a computer, we found that it draws around 0.6 Amps @ 0.6 PF lead !! The filter itself is a passive filter (LC combination) and hence would...
I am working on a design of harmonic rejection filter to reject 3rd harmonics present in neutral. I plan to use a capacitor of 120 uF and inductor of around 9 mH in parallel connection. The analysis shows that this combination has high impedance at 3rd harmonic (150 Hz)but the programme also...
In one of the cement plant where we conducted harmonic audit we found that on the HT 6.6. KV BUS, the Voltage as well as current distortion drastically increased when the supply was switched from Utility supply to their own Captive Turbogenerator supply. It increased from nearly 2% to almost...
We have a glass melting furnace 50 KW fed by a furnace transformer,cycloconverter and an uncontrolled rectifier, feeding the furnace at 11V DC. One of the Energy auditors measured the energy consumption at the input of furnace and found that 223 KWH energy was used to melt only around 3.4 Kgs of...
WE HAVE COME ACROSS A CASE, WHERE A 1250 KVA, 415V DG SET IS NOT ABLE TO TAKE THE LOAD OF 2 DC DRIVES EACH RATED AT 500 KVA. WE HAVE BEEN TOLD BY DG SET MANUFACTURER THAT IT IS DUE TO HARMONICS PRODUCED BY DC DRIVES. THE DG SET IS 415V AND SUPPLY TO DC DRIVES DIRECTLY WITHOUT ANY TRANSFORMER IN...
wE PLAN TO CONNECT A HARMONIC FILTER TUNED TO 4.7TH ACROSS OUR DC DRIVE 250 KW. WILL THERE BE ANY EFFECT ON THE WORKING OF DC DRIVE ? THE DRIVE HAS A DEDICATED TRANSFORMER AND THE FILTER IS PROPOSED TO BE INSTALLED PARALLEL TO THE DRIVE ?
I have a Power Control Centre (415V), from which a feeder feeds around 500 kw of load of Variable speed drives (6-pulse). Another feeder from this PCC feeds a Motor Control centre having 300 KW load. To improve the PF of motors, capacitors are connected across the motors directly.
We are...
how does one calculate the short circuit level on a Low Tension bus when both utility and Captive Power (Diesel Genset) is connected to the same bus. There are all the three possibilities of operation: Utility only, Captive Power only and both utility + captive Power. <br><br>I need...
