Electric Power Generation, Transmission, and Distribution

noninteger multiples of the power frequency, are analytically treated in the same manner, usually based on the principle of supe ...

THDðÞ¼% ffiffiffiffiffiffiffiffiffiffiffi P^1 i¼ 2 F^2 i s F 1 * 100 % (30:2) Because harmonic levels are never constant, it is ...

utility insures that any ‘‘reasonable’’ amount of harmonic current injected by any and all customers does not lead to excessive ...

suggested by the IEC are similar (but not identical) to those given in Tables 30.2 and 30.3, the IEC tables for system-level har ...

to have mathematically correct equipment models and the data to use in them. Assuming that this data is available, there are a v ...

A frequency scan result is actually a plot of impedance vs. frequency. Two types of results are available: driving point and tra ...

It should be noted that passive filtering cannot always make use of existing capacitor banks. In filter applications, the capaci ...

IEC 61000-3-6 TR3,Electromagnetic compatibility(EMC)—Part 3: Limits—Section 6: Assessment of emission limits for distorting load ...

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31 Voltage Sags Math H.J. Bollen STRI 31.1 Voltage Sag Characteristics ............................................. 31 -1 Volta ...

31.1.1 Voltage Sag Magnitude—Monitoring The magnitude of a voltage sag is determined from the rms voltage. The rms voltage for t ...

This is due to the finite length of the window used to calculate the rms value. We also see that the rms value during the sag is ...

Vsag¼ ZF ZSþZF (31:2) where it is assumed that the pre-event voltage is exactly 1 pu, thusE¼1. The same expression can be derive ...

Vsag¼ 1  SFLT SPCC (31:4) This equation can be used to calculate the magnitude of sags due to faults at voltage levels other th ...

withVnomthe nominal voltage. As bothzandIfltare of similar magnitude for different voltage levels, one can conclude from Eq. (31 ...

the pre-event and the during-event voltage. With reference toFig. 31.4andEq. (31.2), the phase-angle jump is the argument ofVsag ...

introduced. The basis of this characterization is the theory of symmetrical components. Instead of the three-phase voltages or t ...

requirements for IT-equipment as recommended by the Information Technology Industry Council (ITIC, 1999). Strictly speaking, one ...

instead of by a full curve. From the tests summarized inFig. 13.8it is found that the voltage tolerance of personal computers va ...

voltage and with a larger ripple. The resulting DC bus voltage for a sag down to 50% is shown in Fig. 31.11, together with the a ...