Transcript GE Power Quality - Levine Lectronics and Lectric

Digital Meters - Power
Quality Monitoring and
John Levine, P.E.
Analysis
Levine Lectronics and Lectric
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Contents
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Effects of power quality
Power Quality definitions revisited
What is needed for PQ monitoring ?
Summary
Monitor and Analyze Power Disturbances, Disruptions & Harmonics
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PQ is a Business Problem
Power Quality issues cause business problems
such as:
• Lost productivity, idle people and equipment
• Lost orders, good will, customers and profits
• Lost transactions and orders not being processed
• Revenue and accounting problems
• Customer and/or management dissatisfaction
• Overtime required to make up for lost work time
According to Electric Light and Power Magazine, 30 to 40 Percent
of All Business Downtime Is Related to Power Quality Problems.
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Is Power Quality Such a Big
Problem?
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Why PQ is such a Big Problem?
• The sensitivity of today’s electronic equipment makes it
susceptible to power disturbances
• For some devices, a momentary disturbance can cause
o scrambled data
o interrupted communications
o a frozen mouse
o system crashes and equipment failure
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PQ Problems are Expensive
•
Berkeley Lab Study Estimates $80 Billion Annual
Cost of Power Interruptions … Research News,
Berkeley Lab, February 2, 2005
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$50 billon per year in the USA is lost as a results
of power quality breakdowns …. Bank of America
Report
•
A manufacturing company lost more than $3
million one day last summer in Silicon Valley
when the “lights went out.” … New York Times
January 2000
•
“A voltage sag in a paper mill can waste a whole
day of production - $250,000 loss” … Business
Week, June 17,, 1996
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Half of all computer problems and one-third of all
data loss can be traced back to the power line …
Contingency Planning Research, LAN Times
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Who is Affected?
• High Cost Facilities
o Semiconductor plants
o Pharmaceuticals
o Data centers
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Medium Cost Facilities
o Automotive manufacturing
o Glass plants
o Plastics & Chemicals
o Textiles
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Lost production
Scrap
Costs to restart
Labor costs
Equipment damage and repair
Other costs
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PQ Definitions Revisited
IEEE Categories
Std 1159-1995
Short Duration
Variations
Typical
Duration
Instantaneous Sag
0.5 – 30 cycles
Momentary Sag
30 cycles – 3
sec
Temporary Sag
3 sec – 1 min
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PQ Definitions Revisited
IEEE Categories
Std 1159-1995
Short Duration
Variations
Typical
Duration
Instantaneous Sag
0.5 – 30 cycles
Momentary Sag
30 cycles – 3
sec.
Temporary Sag
3 sec – 1 min.
Instantaneous Swell
0.5 – 30 cycles
Momentary Swell
30 cycles – 3
sec.
Temporary Swell
3 sec – 1 min.
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PQ Definitions Revisited
IEEE Categories
Std 1159-1995
Short Duration
Variations
Typical
Duration
Instantaneous Sag
0.5 – 30 cycles
Momentary Sag
30 cycles – 3
sec.
Temporary Sag
3 sec – 1 min.
Instantaneous Swell
0.5 – 30 cycles
Momentary Swell
30 cycles – 3
sec.
Temporary Swell
3 sec – 1 min.
Momentary Interruptions
0.5 – 30 cycles
Temporary Interruptions
30 cycles – 3
sec.
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PQ Definitions Revisited
IEEE Categories
Std 1159-1995
Long Duration
Variations
Typical
Duration
Sustained interruptions
> 1 min
Under voltages
> 1 min
Over voltages
> 1 min
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PQ Definitions Revisited
IEEE Categories
Std 1159-1995
Long Duration
Variations
Typical
Duration
Sustained interruptions
> 1 min
Under voltages
> 1 min
Over voltages
> 1 min
Voltage imbalance
Steady state
Waveform Distortion
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PQ Definitions Revisited
IEEE Categories
Std 1159-1995
Long Duration
Variations
Typical
Duration
Sustained interruptions
> 1 min
Under voltages
> 1 min
Over voltages
> 1 min
Voltage imbalance
Steady state
Waveform Distortion
DC offset
Steady state
Harmonics
Steady state
Inter harmonics
Steady state
For Electric Utilities Control of Voltage and Prevention of Outages is Power
Quality
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Sources of PQ Problems
Utility Sources
• Lightning
• PF Correction
Equipment
• Faults
• Switching
Internal Sources
• Individual Loads –Lighting, Elevators, Coolers,
HVAC
• Uninterruptible Power Supplies
• Variable Frequency Drives
• Battery Chargers
• Large Motors During Startup
• Electronic Dimming Systems
• Lighting Ballasts (esp. Electronic)
• Arc Welders, and Other Arc Devices
• Medical Equipment, e.g. MRIs and X-Ray
Machines
• Office Equipment and Computers
• Wiring
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PQ Problems and Possible Causes
Typical problems
Disturbance Type
Possible Causes
Overheated neutral
Intermittent lock-ups
Frequency deviations
Steady-state
Shared neutrals
Improper or inadequate wiring
High source impedance
SCR/Rectifiers and notching
Harmonics
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PQ Problems and Possible Causes
Typical problems
Disturbance Type
Possible Causes
Overheated neutral
Intermittent lock-ups
Frequency deviations
Steady-state
Shared neutrals
Improper or inadequate wiring
High source impedance
SCR/Rectifiers and notching
Harmonics
Interruption
Garbled data
Random increase in harmonics levels
Utility faults
Inrush currents
Inadequate wiring
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PQ Problems and Possible Causes
Typical problems
Disturbance Type
Possible Causes
Overheated neutral
Intermittent lock-ups
Frequency deviations
Steady-state
Shared neutrals
Improper or inadequate wiring
High source impedance
SCR/Rectifiers and notching
Harmonics
Interruption
Garbled data
Random increase in harmonics levels
Intermittent lock-ups
Lights flicker
Garbled data
Utility faults
Inrush currents
Inadequate wiring
Sags/Swell
Source voltage variations
Inrush/surge currents
Inadequate wiring
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PQ Problems and Possible Causes
Typical problems
Disturbance Type
Possible Causes
Overheated neutral
Intermittent lock-ups
Frequency deviations
Steady-state
Shared neutrals
Improper or inadequate wiring
High source impedance
SCR/Rectifiers and notching
Harmonics
Interruption
Garbled data
Random increase in harmonics levels
Utility faults
Inrush currents
Inadequate wiring
Intermittent lock-ups
Lights flicker
Garbled data
Sags/Swell
Source voltage variations
Inrush/surge currents
Inadequate wiring
Component failure
Dielectric breakdown
Lock-ups
Garbled data
Wavy CRTs
Impulses
EMI/RFI
Lightning
Load switching
Capacitor switching
Static discharge
Hand-held radios
Loose wiring/arcing
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PQ Problems and Possible Causes
Typical problems
Disturbance Type
Possible Causes
Overheated neutral
Intermittent lock-ups
Frequency deviations
Steady-state
Shared neutrals
Improper or inadequate wiring
High source impedance
SCR/Rectifiers and notching
Harmonics
Interruption
Garbled data
Random increase in harmonics levels
Utility faults
Inrush currents
Inadequate wiring
Intermittent lock-ups
Lights flicker
Garbled data
Sags/Swell
Source voltage variations
Inrush/surge currents
Inadequate wiring
Component failure
Dielectric breakdown
Lock-ups
Garbled data
Wavy CRTs
Impulses
EMI/RFI
Lightning
Load switching
Capacitor switching
Static discharge
Hand-held radios
Loose wiring/arcing
Overheated transformers and motors
Voltage and current distortions
Garbled data
Lock-ups
Harmonics
Electronic loads
SCR/rectifier
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Major PQ Problems
Outages,
6%
Spikes, 7%
Swells,
Sags, 56%
31%
Source: EPRI, 1994
Swells
Sags (Dips)
System fault conditions
Associated with system faults
Switching on a large capacitor bank
Switching of heavy loads
Switching off a large load
Starting of large motors
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Cost of Voltage Sags
Textile Industry
Plastics Industry
Glass Industry
Process Industry
Semiconductors
$1k
$10k
$100k
$1M
$10M
Source: EPRI “The Economics of Custom Power”, IEEE T&D Show 2003
Losses per Voltage Sag Event
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Cost of Momentary Outages
Momentary Outages
create problems when
computers and clocks
reset, equipment stalls,
and work stops.
Category
Industrial
Semiconductor Manufacturing
Electronics
Automobile Manufacturing
Pharmaceutical
Glass
Rubber and Plastics
Petrochemical
Food Processing
Textile
Metal Fabrication
Mining
Paper
Printing(Newspapers)
Cost of Momentary Interuption
($/ kW Demand)
Minimum Maximum
Commercial
Hospitals, banks, civil service
Communications, information processing
Resturants, bars, hotels
Commercial shops
$20.0
$8.0
$5.0
$5.0
$4.0
$3.0
$3.0
$3.0
$2.0
$2.0
$2.0
$1.5
$1.0
$60.0
$12.0
$7.5
$50.0
$6.0
$4.5
$5.0
$5.0
$4.0
$4.0
$4.0
$2.5
$2.0
$2.0
$1.0
$0.5
$0.1
$3.0
$10.0
$1.0
$0.5
Source: EPRI “The Economics of Custom Power”, IEEE T&D 2003
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High Speed Waveform Capture
High Speed Waveform Capture Is the Most Important PQ
Troubleshooting Tool
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Benefits of Continuous PQ Monitoring
• Power Quality monitoring provides a continuous
“Health Check” of a facility’s power system … for
example:
o
Harmonic interaction between loads and
power conditioning equipment spotted
o
High Inrush currents from equipment
startup detected
o
Transients from load switching are seen
• It provides data to see, diagnose and avert
looming problems – “like squeaky brakes on a
car”
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Trends can be detected
o
JIT equipment maintenance programs
can be established
• It acts like a “Black Box” on an airplane to tell
you what, when, and where a Power Quality
event occurred … to prevent it from reoccurring
Continuous PQ Monitoring Detects, Records, and Leads
to the Prevention of PQ Problems
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What is needed for PQ Monitoring?
PQ Monitors must detect and record
the 7 types of PQ problems
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Transients
Interruptions
Sag/Under Voltage
Swell/Over Voltage
Waveform Distortion
Voltage Fluctuations
Frequency Variations
These include Flicker and
Compliance to ITI(CBEMA), IEEE
and ISO Standards
Plus they must …
• Be easy to use
• Be Suitable for continuously
monitoring indoors and outdoors
• Interface with standard PQ analysis
Software…PQDif format
• Be fast enough to capture high
speed events that produce
equipment problems
• Have enough storage to save the
waveforms you need
• Have PQ analysis tools that
produce usable, actionable
recommendations
ITI: Information Technology Industry Council (Computer & Business Equipment Manufacturer’s Association)
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Real Time Field Recorded Events
Source: AGA Brazil
Meter: EPM9650
Period: Jan 2005 – Dec
2005
Continuous Monitoring of the Station for PQ Problems
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PQ Meter ITI Capture
ITI Acceptable Power
Disturbance Envelope
Damage Inducing Voltage
Surges as Recorded
Equipment Interrupting
Voltage Sags as Recorded
ITI: Information Technology Industry Council (Computer & Business Equipment Manufacturer’s Association)
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Instantaneous Sag Event
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Instantaneous Swell Event
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Harmonic & Interharmonic Spectrum
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Flicker Recording
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Flicker Recording
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Summary
GE Multilin provides the necessary tools for a successful PQ
disturbance analysis and allows users to take remedial actions
Symptoms
Feels the pulse of the
power system network
Examinations Accurate Measurement to
determine actual state
High resolution recordings
for longer durations
Diagnosis
GE Communicator
software
Remedy
Remedial actions
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Finally…
If You Can’t Measure it You Can’t Manage
it
If You Can Measure it You Can Manage
it
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Proper Phasors
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Proper Phasors
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