EE 741
Photovoltaic (PV) Systems:
Impact on Distribution
Feeder Operation
Yahia Baghzouz, Professor
Impact on PV Systems on Voltage Profile
Under sunny skies, PV systems reduce the
real part of the load current.
This results in a voltage rise, but lower p

EE 741
Spring 2014
Distribution System Load
Characteristics
Load Characteristics
Some definitions
Relation between load and loss factors
Load management
Rate (tariff) structures
Metering
Conservation Voltage Regulation
Trend from linear to non-linear load

EE 741
Spring 2014
Sub-transmission Lines and
Distribution Substations
Overview
Types of sub-transmission layouts
Substation equipment
Substation bus schemes
Substation location
Substation rating (voltage drop calculations.)
Substation application curves

EE 741
Primary & Secondary Distribution
Systems
Radial-Type Primary Feeder
Most common, simplest and lowest cost
Example of Overhead Primary Feeder Layout
Example of Underground Primary Feeder Layout
Radial-Type Feeder with Tie and Sectionalizing Switche

ECG 741 COURSE SYLLABUS
Fall 2014
Instructor: Dr. Y. Baghzouz
Office Room # SEB-2167
Tel. # 895-0887
Fax # 895-4075
Email address: yahia.baghzouz@unlv.edu
Book Title: T. Gonen, Electric Power Distribution System Engineering, 2nd Edition, CRC
PRESS, 2008
R

EE 741
Over-voltage and Overcurrent Protection
Spring 2014
Causes of Over-voltages
Lightning
Capacitor switching
Faults (where
interruption occurs prior
to zero current crossing)
Accidental contact with
higher voltage systems
Ground Flash Density in U

EE 741 Test 3 (Take Home Part Use EasyPower Software)
Name:
Consider a 10 mi long feeder that serves a 5 MVA (80% Power Factor) uniformly
distributed load from a 69kV/13.2kV 15 MVA substation transformer with 8%
impedance. The uniform load can be lumped a

EE 741
Power Quality
Spring 2014
Definition
Power Quality ca ne defined as the goodness of the
electric power supply in terms of its voltage and current
wave-shapes, its voltage regulation, continuity of power
supply and its frequency.
Perfect Power ref

ECG 741
Power Distribution Transformers
Y. Baghzouz
Spring 2014
Preliminary Considerations
A transformer is a device that converts one
AC voltage to another AC voltage at the same
frequency. The windings are wrapped on top
of each other to decrease flux l

EE 741
Spring 2014
Distribution Planning and
Automation
Distribution Planning
Distribution system expansion to meet load growth
requires careful planning.
The objective of distribution system planning is to
provide reliable service to customers at the l

ECG 741
Power Transformers II
Y. Baghzouz
Spring 2014
Delta-Delta Connection
Wye-Wye Transformer Connection
4. - connection:
No phase shift, no problems with
unbalanced loads or harmonics.
Wye-Delta Transformer Connection
Delta-Wye Transformer Connection

EE 741
Spring 2014
Application of Capacitors
Shunt Capacitors
Supply reactive power, reduce current, release capacity,
correct the power factor, regulate the voltage
Power Factor Correction
Types of Capacitor Switching Methods
Time control
Temperature c

EE 741
Energy Storage
Spring 2014
Rationale for Energy Storage
The current and anticipated challenges facing the
electric grid include the following:
Variability in solar photovoltaic (PV) power output due to
the diurnal solar cycle, passing clouds, and

EE 741
Voltage Regulators
Spring 2014
Typical Voltage Profile from Substation to Customer
Step-Voltage Regulator
These devices are essentially autotransformers with adjustable turns in the
series winding.
They usually have a maximum voltage
regulation r

ECG 741 CHAP 3 HOMEWORK
Problems 2.4-7
Consider the load data below of an urban feeder. Determine the following:
1) The average load, peak load, and load factor
2) The load diversity
3) The loss factor, and the average power loss (assume the power loss at