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An equivalent source at 69 kV has a three-phase short circuit capacity of 1180 MVA with X/R = 10. It feeds a dedicated feeder through a 30 MVA, 69 kV/12.47 kV transformer with a leakage impedance of 5%. A group of nonlinear loads consisting of computers and network server is fed by a 1.5 MVA, 12.47 kV/480 V service transformer. The leakage impedance of the transformer is 4%. A wye-grounded capacitor bank rated at 3.287 MVAr, 12.47 kV is installed at the secondary of the 69 kV/12.47 kV transformer. The nonlinear load has the fundamental current of 450 A and it produces 11th order harmonic current of 5.3 % of the fundamental. The system is shown in Figure 5.

1). Draw an equivalent circuit at the fundamental frequency of the 12.47 kV system. The equivalent circuit must show values of impedances and current magnitude at the 12.47 kV feeder.

2) Determine the system parallel resonant frequency at the 12.47 kV system and repeat question (1) at the resonant frequency.

3) Mitigate the harmonic problem by shifting the parallel resonant frequency to a non-characteristic harmonic frequency by modifying the size of the capacitor. What is the appropriate size of the capacitor bank while keeping the steady state voltage rise less than 2.0%?

4). Mitigate the harmonic problem by blocking the harmonic current from entering the 12.47 kV systems. Install the filter for the 11th harmonic at the 480-V bus. The filter will also improve the power factor from 0.75 lagging to 0.96 lagging. Determine the appropriate capacitor and reactor size for the filter.

 

 

 

 

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Network Forging

The requirement for socialization and personality makes a nearby network connect that numerous individuals keep up all through their lifetime. Their lives may focus on religion, ethnicity, or even the financial class to which the person has a place. The people group mirrors these angles by gathering people in comparable circumstances and convictions. The bound Western dress of Pang-Mei Natasha Chang clarifies the significance of custom and culture in the network’s personality by clarifying the connection between conventional Chang Yu-I’s life and Westernized Xu Zhimo I am communicating.

Both Findhorn and Auroville were built up as a rebel ideal world, a retreat of the Western world that was established during the 1960s. Joined by delicate total of different conviction frameworks, these are cognizant networks – global free self-ruling ideal world network, not a network worked by history, culture or group. A significant number of these organizations have fizzled (478 cognizant networks have contracted to 112 in the previous a long time since the 1920 ‘s), they are presently the two biggest otherworldly focuses on the planet. They have around 200 enormous private networks and bolster themselves by offering courses for some guests (Findhorn has 1,200 paid visitors for each year and Auroville has There are more than 50,000 guests).

In 1953, humanist Robert Nisbet recommended that another type of network “identified with contemporary life and thought” ought to be in any event incompletely settled via scanning for a more grounded network. This idea despite everything applies, except today it might mean thinking about how religion, governmental issues, and network support are most appropriate to the American reality. To do that, we have to make ventures to make parks and entertainment focuses alluring and advance the development of the network. At the end of the day, this implies underlining and upgrading hierarchical examples that give individuals the force – to give them instruments to recover their capacity

For the offspring of the club, this is an issue, they generally respect innovation and family authority – adjustment and homogenization as an approach to assemble a network. They emanate their own natural cadence delicately from the phase toward a radiant doof-doof-doof so they use medication to become companions, medication and become companions . A couple of years prior, in the equivalent “Yearly Trends” paper, Disclosure and Rudimental ‘s “move/well known” revisionism was appreciated and pundit Philip Sherburne composed that move music observes “Cheerful Giving” once more. In 2015, a gathering of individuals of this sort of vanguard group surrendered delight

 

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