Electric Power Generation, Transmission, and Distribution

The per-unit models ofEqs. (20.1)and (20.2)are as follows. Pu¼ P Po ¼ V Vo av f fo af (20:3) Qu¼ Q Po ¼ Qo Po V Vo bv f fo ...

where aoþa 1 þa 2 ¼ 1 boþb 1 þb 2 ¼ 1 Dpreal power frequency damping coefficient, per unit Dqreactive power frequency damping ...

where Ppoly¼a 0 þa 1 V Vo  þa 3 V Vo  2 (20:12) Pexp1¼a 4 V Vo a 1 [1þDp1Df] (20:13) Pexp2¼a 5 V Vo a 2 [1þDp2Df] (20:14 ...

protective relay operations. At the utilization level, motors on air conditioner units and motors in many other residential, com ...

add to 100%. The entries across from each component load for a given window type represent the percentage of that load making up ...

21 Distribution System Modeling and Analysis William H. Kersting New Mexico State University 21.1 Modeling ..................... ...

The following sections will present generalized three-phase models for the ‘‘series’’ components of a feeder (line segments, vol ...

Self-impedance: ^zzii¼riþ 4 ˆPiiGþj Xiþ 2 ˆGiiln Sii Ri þ 4 ˆQiiG  V=mile (21:1) Mutual impedance: ^zzij¼ 4 ˆPijGþj2ˆG ln Sij ...

Using these approximations and assumptions, Carson’s equations reduce to: ^zzii¼riþ 0 : 0953 þj 0 :12134 ln 1 GMRi þ 7 : 93402  ...

The phase frame matrix can be used to accurately determine the voltage drops on the feeder line segments once the currents flowi ...

The resulting sequence impedance matrix is of the form: ½Š¼z 012 z 00 z 01 z 02 z 10 z 11 z 12 z 20 z 21 z 22 2 4 3 (^5) V=mile ...

The GMDs as defined above are used inEqs. (21.9)and (21.10)to determine the various self and mutual impedances of the line resul ...

FromFig. 21.4the following distances between conductors can be determined: Dab¼ 2 :5ft Dbc¼ 4 :5ft Dca¼ 7 :0ft Dan¼ 5 :6569 ft D ...

The results of this example should not be interpreted to mean that a three-phase distribution line can be assumed to have been t ...

GMRs¼geometric mean radius of a neutral strand (ft) rc ¼resistance of the phase conductor (V=mile) rs ¼resistance of a solid neu ...

Example 21.2 Three concentric neutral cables are buried in a trench with spacings as shown in Fig. 21.8. The cables are 15 kV, 2 ...

21.1.1.8 Tape Shielded Cables Figure 21.9 shows a simple detail of a tape shielded cable. Parameters of Fig. 21.9 are dc¼diamete ...

In applying Carson’s equations for both concentric neutral and tape shielded cables, the numbering of conductors and neutrals is ...

21.1.2 Shunt Admittance When a high-voltage transmission line is less than 50 miles in length, the shunt capacitance of the line ...

Example 21.4 Determine the shunt admittance matrix for the overhead line of Example 21.1. Assume that the neutral conductor is 2 ...