Solve Delta/Wye Transformer Questions - 22kV to 345kV

[blanik]

Can someone point me in the correct direction to solve these...

A 22 kV generator is stepped up to 345kV with a delta-wye transformer. The power is transmitted 100 miles over wires with a resistance ov 18.9mOhms/ft and an inductance of 2.51 microHenries/ft. The transmission is stepped back down with a 345kV to 23kV wye-delta transformer. The is 30MW with a PF of 0.92, lagging.

a. What is the actual voltage at the load?
b. What is the PF at the generator?
c. What fraction of the generated power is lost in delivery.

I have calculated S as P/PF. And I=(W/PF)/(sqrt3xV). Do I calculate V at the load using S=VxI?

Is the PF at the generator 100%?

Is the fraction lost 0.08?

 

[Valkarie]

a. To calculate the actual voltage at the load, you need to calculate the total impedance of the transmission line, which is given by Z = R + (L*w), where w is the angular frequency of the AC signal. From this, you can calculate the current I = V/Z. Then, you can use the power equation P = V*I*PF to calculate the voltage at the load. b. The PF at the generator is equal to the PF of the load, which is 0.92. c. The fraction of the generated power that is lost in delivery is equal to 1 - (P_load/P_generator). In this case, it is 0.08.

 

[piercas]

I would advise you to first review the concepts of delta-wye transformers, power transmission, and power factor. It is important to have a thorough understanding of these concepts before attempting to solve the given questions. Once you have a solid understanding, you can approach the problem by using the given information to calculate the voltage at the load, the power factor at the generator, and the fraction of power lost in delivery. To calculate the voltage at the load, you can use the formula S=VxI, where S is the apparent power, V is the voltage, and I is the current. You can also use the formula S=P/PF, where P is the real power and PF is the power factor. To calculate the power factor at the generator, you can use the formula PF=P/S. And to calculate the fraction of power lost in delivery, you can use the formula (1-PF)^2. Remember to convert all units to the appropriate values (e.g. miles to feet) before plugging them into the formulas. Additionally, it is important to double check your calculations and make sure they are consistent with the given information and formulas. I hope this helps guide you in the right direction to solve these questions.