Electrical Distribution Feeder Analysis
EE 4225 Project
Distribution Feeder Analysis
11/29/2010
Kris Bartell
Matt Drzewiecki
Evan Zaborski 1.0 Abstract
This project offered the opportunity to simulate the voltage profile of an IEEE sample distribution feeder. Through an iterative process, this can be accomplished using a series of calculations. To achieve this goal, the simulation package Matlab was used as the driving force behind the programming and calculating. Discussion
2.1 Individual Segment Modeling
To simulate the feeder, the first thing needed is a model of each line segment. To construct this model, code can be written that computes the distances between conductors by using the configurations and conductor values given for each line segment. These results provide the information needed to create the primitive impedance matrix, Zprim. Using the matrix operation known as Kron reduction, shown in Equation (1) below, these primitive matrices can be converted into Zabc impedance matrices.
Z=A-BC^(-1) D (1)
Each matrix can then be multiplied by its respective segment length to convert to actual ohmic values of line resistance. These matrices represent the main part of the line model.
2.2 Load Modeling
Each load connected to the feeder can now be modeled. To accurately simulate the voltage profile, three types of loads will be modeled. These include a constant current load, a constant impedance load, and a load with constant real and reactive power. To simplify needed calculations, each delta-connected load shall be converted to a wye-connected load using Equation (2).
Z_Υ=Z_Δ/3 (2)
The current required for each load can now be calculated based on the nominal line voltage.
2.3 Iterative Process
Using these currents the voltage drop can be computed for each line segment. Now the second part of the iteration can begin, calculating the voltages at all the nodes. Using the voltage drops the new node voltages can be computed. After the node voltages have been
Distribution Feeder Analysis
11/29/2010
Kris Bartell
Matt Drzewiecki
Evan Zaborski 1.0 Abstract
This project offered the opportunity to simulate the voltage profile of an IEEE sample distribution feeder. Through an iterative process, this can be accomplished using a series of calculations. To achieve this goal, the simulation package Matlab was used as the driving force behind the programming and calculating. Discussion
2.1 Individual Segment Modeling
To simulate the feeder, the first thing needed is a model of each line segment. To construct this model, code can be written that computes the distances between conductors by using the configurations and conductor values given for each line segment. These results provide the information needed to create the primitive impedance matrix, Zprim. Using the matrix operation known as Kron reduction, shown in Equation (1) below, these primitive matrices can be converted into Zabc impedance matrices.
Z=A-BC^(-1) D (1)
Each matrix can then be multiplied by its respective segment length to convert to actual ohmic values of line resistance. These matrices represent the main part of the line model.
2.2 Load Modeling
Each load connected to the feeder can now be modeled. To accurately simulate the voltage profile, three types of loads will be modeled. These include a constant current load, a constant impedance load, and a load with constant real and reactive power. To simplify needed calculations, each delta-connected load shall be converted to a wye-connected load using Equation (2).
Z_Υ=Z_Δ/3 (2)
The current required for each load can now be calculated based on the nominal line voltage.
2.3 Iterative Process
Using these currents the voltage drop can be computed for each line segment. Now the second part of the iteration can begin, calculating the voltages at all the nodes. Using the voltage drops the new node voltages can be computed. After the node voltages have been