1) A three-phase substation transformer operating at 34.5kV is loaded to
24 MVA. What is the per-phase current? (assume balanced
conditions)
2) If the current calculated above lags the voltage by 30°, what is the
breakdown of active and reactive loading on the transformer? (assume
balanced conditions)
1) A three-phase substation transformer operating at 34.5kV is loaded to 24 MVA. What is the...
A three-phase Y-A transformer is rated 225-kV:24-kV, 400 MVA and has a single-phase equivalent series reactance of 6.08 ? as referred to its high-voltage terminals. The transformer is supplying a load of 375 MVA at 0.89 power factor leading at a voltage of 24 kV (line to line) on its low-voltage side. It is supplied from a feeder whose impedance is 0.17 +/2.2 ? connected to its high-voltage terminals. For these conditions, calculate (a) the line-to-line voltage at the high-...
Question I The rating of a three phase three winding transformer are: Y-connected 10 KV 40 MVA Secondary Y-connected 22 KV 40 MVA A-connected 4 KV 15 MVA Primary Tertiary Neglecting winding resistance and exciting current, the per unit leakage reactance are: Mps 9.6 % pu on 40 MVA, 11022 KV xm = 7.2 % pu on 40 MVA, I 10/ 4 KV Xsti: 12 % pu on 40 MVA, 22/ 4 KV Determine the era nyimpedances of the transformer...
(30) Assume that a distribution substation, shown below, has a 4000 kVA 69/12.47 kV LTC 4) transformer feeding a three-phase four-wire 12.47 kV distribution system. The transformer has a reactance of 0.065 pu. Assume that fault impedance is 40 Q and that the maximum and minimum power generations of the system are 600 and 360 MVA, respectively. Use 1 MVA as the three-phase power base: a) Under the maximum (system) power generation conditions, determine the available three- phase, L-L, and...
(30) Assume that a distribution substation, shown below, has a 4000 kVA 69/12.47 kV LTC 4) transformer feeding a three-phase four-wire 12.47 kV distribution system. The transformer has a reactance of 0.065 pu. Assume that fault impedance is 40 Q and that the maximum and minimum power generations of the system are 600 and 360 MVA, respectively. Use 1 MVA as the three-phase power base: a) Under the maximum (system) power generation conditions, determine the available three- phase, L-L, and...
Problem 2: A three-phase transformer bank (1-phase transformers) is to handle 30 MVA and have a primary voltage of 115kVLL and a secondary voltage of 4.16kVLL. Find the rating of each individual transformer in the bank (high side voltage, low side voltage, transformer turn ratio, and apparent power rating of each transformer) if the bank is connected: Wye-Wye Wye-Delta Delta-Wye Delta-Delta Draw winding connections for (a)-(d) (NOTE: This step does not need to be done in MATLAB). Assume all delta...
Outcome 2. Assume you need to size voltage regulators for a distribution substation transformer. A copy of the transformer nameplate is given on the back. Assume your utility allows this transformer to run 20% overloaded for 4 hours a day. Part 1 Review the nameplate and provide: 1. OA Rating MVA 14 2. Low side voltage 14.3 kV Part 2 Recommend a three-phase voltage regulator by giving its capacity and line current ratings for a wye-wye connection. Power Rating (kVA):...
5. Consider the one-ine diagram shown below. The three-phase transformer bank is made up of three identical single-phase transformer, each specified by X1-0.004 Ω (on the high-voltage side), negligible resistance and magnetizing current, and turns ratio N2/N,-10. The transformer bank is delivering is delivering 110MW at 0.9 power factor leading to a substation bus voltage is 230kV. Determine the reactive power supplied by the source. (3.47) whose To rest of the system Generator ΔΥ 230-kV substation bus Step-up transformer bank...
3) A two-winding transformer, three phase, 345/230 kV has a single phase capacity of 500 MVA: (a) Determine the total 3-phase capacity, if it is connected as Auto-XMR (b) Determine the voltage and current capacity per each phase Js. LI V, s, V
A 400-MVA, 200-kV/20-kV, three phase Y-Y transformer has an equivalent series impedance of ZTL = 0.012 + 20.0162 per phase referred to the low-voltage side (secondary side). The transformer is supplying a three-phase load of 300-MVA, 0.8 power factor lagging at terminal voltage of 20 kV (line-to-line) on its low-voltage side (secondary side) as shown in Fig. 22. The primary is supplied from a transmission line with an impedance of ZL = 0.5 + j1.0 per phase. The line-to-neutral load...
Please show detailed steps. Thanks
Problem # 1: Three Phase Power [35 points] A three-phase substation bus supplies three wye-connected three phase loads that are connected in parallel through a three-phase feeder with an impedance of 0.3 30 per phase Load 1 draws 75kVA at 0.866 lagging power factor, load 2 draws 45 kW at 0.70 leading power factor and load 3 draws 20 kVAR at 0.85 lagging power factor. The line-line voltage at the load is 460V Take the...