• Uninterruptable Power


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    • Abstract: Uninterruptable PowerSupply (UPS)Introduction, Batteriesand Maintenance1 Common TerminologyAC Power : refers to voltage which cyclesfrom negative to positive levels withrespect to ground. This is what is typically

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Uninterruptable Power
Supply (UPS)
Introduction, Batteries
and Maintenance
1
Common Terminology
AC Power : refers to voltage which cycles
from negative to positive levels with
respect to ground. This is what is typically
supplied to most common types of loads.
DC Power : refers to a steady state of
voltage. All batteries provide a DC output.
2
Common Terminology
UPS : Uninterruptable Power Supply
PDU : Power Distribution Unit
Battery Bank : Any number of batteries
connected in a series string.
Rectifier : A device used for converting
AC power into DC power.
Inverter : A device used for converting DC
power into AC power.
3
Common Terminology
Ground : A reference point which
indicates a 0V level.
Neutral : A conductor which provides a
return path for power.
Single Phase : 120, 240 Vac power
supply.
Three Phase : 208, 480, 600 Vac power
supply.
4
UPS Systems
The fundamental function of all UPS
systems is to provide a source of power to
a critical load when the primary power has
been disrupted.
A secondary function of a UPS system is
to provide power protection from voltage
fluctuations (i.e. Brown outs, spikes…)
5
UPS Systems
Static UPS systems typically consist of the
following:
Rectifier: converts AC to DC.
Inverter: converts DC to AC
Battery Bank: provides a secondary source of
power.
Static Switch: A device which allows a power
bypass around the UPS to occur.
6
UPS Systems
UPS systems have three general modes
of operation:
Normal Operation
On Battery
On Bypass
7
Technology Features
IGBT (Insulated Gate Bipolar Transistor)
Enables high efficiency at full and partial load
conditions
PWM (Pulse Width Modulation) enhanced with
Space Vector Modulation
Excellent output performance
Digital Control Circuitry
16-bit Microprocessor
computing resources for control of power module
regulation and UPS event handling
Dedicated IC model generator Fully digital
Stable output voltage wave form
Less parts count
High output voltage quality even at highly non-linear
loads conditions
8
Technology Features
No Potentiometers
Easier parameters set-up through the monitoring system
More accurate and higher stability of installed values
Digital Phase Locked Loop (PLL)
High output frequency accuracy and a more precise
synchronization between mains and inverter
High integration: Single control board
Improved serviceability
DSP (Digital Signal Processing)
Rapid response
Digital rectifier regulation – Controlled by microprocessor
Hybrid digital & analog inverter regulation
9
What’s wrong with Power
Power Experts, Hydro Utilities, IEEE agree, that there are
9 Common Power Problems that exist in our day to day
electrical systems
Power failures High voltage spikes
Power sags Frequency variations
Power surges Switching transients
Brownouts Harmonic distortion
Line noise
10
Off-Line UPS
Normal Mode - Utility Present
Utility
Power
Surge
Suppression
EMI/RFI
Filters
Load
Battery
Charger Inverter
Battery
• Load is normally connected to utility
• Load power does not flow through inverter
11
Off-Line UPS
Battery Mode - Utility Outage, Power Problems
Utility
Power
Surge
Suppression
EMI/RFI
Filters
Load
Battery
Charger Inverter
Battery
• 4 mS break in power to critical load
12
Off-Line UPS features
• lowest initial cost
• basic power outage protection
• Power failure
Off-line • Brownouts
• High voltage
spikes
13
Line-Interactive UPS
Normal Mode -- Utility Present
Voltage
Regulator
Utility EMI RFI
Filter
Load
Charger Inverter
Battery
• UPS “interacts” with line by regulating voltage
• Load power does not flow through inverter
14
Line-Interactive UPS
Battery Mode -- Voltage fluctuation
Voltage
Regulator
Utility EMI RFI
Filter
Load
Charger Inverter
Battery
15
Line-Interactive UPS
Battery Mode -- Utility Outage
Voltage
Regulator
Utility EMI RFI
Filter
Load
Charger Inverter
Battery
• 4 mS break in power to critical load
16
Line-Interactive UPS
• higher initial cost vs. off-line UPS
• power outage protection
• voltage regulation without going to battery
• Power failure
• Brownouts
Line-
Interactive • High voltage spikes
• Power sags
• Power surges
17
On-Line UPS
Normal Mode -- Utility Present
Static Bypass Switch
Utility Rectifier Inverter Load
Battery
• Load power flows through rectifier and inverter (double conversion)
18
On-Line UPS
Normal Mode -- Utility Problem
Static Bypass Switch
Utility Rectifier Inverter Load
Battery
• Load power flows through rectifier and inverter (double conversion)
19
On-Line UPS
Battery Mode -- Utility Outage
Static Bypass Switch
Utility Rectifier Inverter Load
Battery
• No interruption
20
On-Line UPS
Bypass Mode
Static Bypass Switch
Utility Rectifier Inverter Load
Battery
•Transfer to bypass in case of failure
21
On-Line UPS - Features
• most power protection and highest reliability
• voltage and frequency regulation without going to battery
• longest battery life
• blocks harmonic load currents
• automatic internal bypass for higher availability
• High voltage spikes • Frequency variation
• Power failure • Harmonic distortion
On-line • Brownouts • Power surges
• Power sags • Switching transients
• Line noise
22
Power Distribution
PDU’s serve as a single point interface
between the UPS system and critical
loads.
Most PDU’s will also provide voltage
regulation, ground transient suppression,
and a convenient point to tie neutral and
ground conductors.
23
Power Distribution
24
Power Distribution
25
Facility Power System
26
UPS Applications
IT – Multiple Workstations, Servers, Networks, Data Centers
Service Providers – Network Service Providers
Health Care – Medical Imaging Equipment, Lab Equipment
Transportation – Air, Rail, Subways, Motorways
Telecommunications – TV, Cellular, Satellite
Process Control & Automation – Pharmaceutical, Water & Waste
Treatment, Automotive
Finance – Banking, Insurance
Mission Critical Applications
27
Batteries
28
The battery is the most vulnerable part of any uninterruptible power supply
(UPS), regardless of capacity, topology or brand. The battery is ultimately at
the heart of the UPS in terms of reliability. Understanding causes of battery
degradation, ways to prevent degradation and maintenance options are
fundamental to ensure maximum system availability.
IEEE defines the end of useful life for a battery as the point when it can no
longer supply 80% of its rated capacity in ampere-hours. Because the
relationship between amp-hours and load protection time is not linear, a 20%
reduction in capacity results in a much greater reduction in protection time.
For example, a UPS battery that supports a full load for 15 minutes when
new will support the same load for only about eight minutes when it reaches
its defined end of life. When the battery reaches 80% of its rated capacity,
the aging process accelerates--and the battery should be replaced.
29
Since few changes have occurred in battery technology, UPS manufacturers
have sought alternative measures to monitor batteries and extend battery life.
Advances in monitoring and managing UPS batteries through software and other
communications devices have continued to improve, providing a key component
of extending battery life.
Most UPSs still use either sealed or flooded cell batteries. Flooded cell, or wet
cell, batteries are typically found in larger, three-phase UPSs. These batteries are
similar to car batteries, where the water level is routinely checked and water can
be added if needed. Sealed batteries use a suspended gel electrolyte instead of
water and do not require the fluid level to be replenished. Though sealed
batteries are often called maintenance free, they still require scheduled
maintenance and service.
30
There are four major factors that affect UPS battery life
(both sealed and flooded cells): ambient temperature,
battery chemistry, cycling and lack of service.
31
Maintenance Techniques Of Managing Batteries
•Battery circuit tests perform a periodic pulse test of the battery string to
ensure that there are no open circuits that would jeopardize battery
performance and system availability.
•Temperature-compensated charging monitors the battery temperature and,
through sophisticated algorithms, adjusts the rate of charge, compensating
for heat, to prolong the life of the battery.
32
Maintenance Techniques Of Managing Batteries
The final factor to consider is the service of the batteries and the UPS.
The gradual decrease in battery life can be monitored and evaluated
through voltage checks, as well as load testing. Maintenance program
extends battery string life by preventing loose connections, removing
corrosion and identifying bad batteries before they can affect the rest of
the string.
Without regular maintenance and service checks, a UPS battery may
experience: heat-generating resistance at the terminals, improper
loading, reduced protection and premature failure. Temperature, float
level, cycling and other factors all affect UPS battery life. Batteries can
degrade to the point that they are unable to provide adequate run time for
a UPS. Battery monitoring can provide the solution to keep mission-
critical systems fully protected.
33
UPS Maintenance
34
Downtime….
4% Batteries
15%
UPS Part Problems
36%
UPS in Overload
19% Human Error
Non-UPS
4% Equipment Problem
22%
UPS in Bypass
When Power
Outage Occurred
62% of load drops could have been eliminated
or greatly reduced by appropriate preventive and
remedial maintenance
35
Preventative maintenance is crucial to achieve the maximum
performance and lifespan from your critical power equipment this
gives you the opportunity to detect and repair problems, minimizing
your risk for unplanned downtime
36
The small periodic time investment to check batteries, connections,
fans, relays and sensors is well spent compared to damage or lost
data and broken hardware after a power disturbance reveals a dead
UPS system. We know of systems one to three years old that had
failed in an outage. These units failed because of lack of battery
maintenance, blocked air filters and fan failures. Poor battery
connections, dirt and dust within the unit also cause premature
failure and unexpected added expense.
37
Components of an Electrical Power
“Risk Management Plan” Predictive
Monitoring Usage
Maintenance Plan
For Equipment
Dual Power Feeds from the Utility
Paralleling Switch Gear
Uninterruptible Power Systems (UPS’s) and Batteries
Generators and Fuel Tanks
Automatic Transfer Switches (ATS’s)
Trans Voltage Surge Suppressors (TVSS’s)
38
Communication
39
In today’s world technology has been advancing in a lot of
different ways mainly how we interact and communicate every
day example, Cell phones, Emailing, Internet etc
UPS communication has also come a long way from just
supplying a common trouble alarm signal to the operator. Thru
UPS software systems are designed to send out these alarms to
your cell phones & operators are able to communicate with the
UPS systems outside their work place. The software also gives
you the capability to download key events from the alarm log
and monitor the status like all metering on the UPS.
40
41
• Client/Server structure for both
standalone and network
applications
• Simultaneous SNMP Agent/Client
capabilities
• Script execution capability for
shutdown and “on alarm” actions
+ E-mail notification
• Password protection for any
critical operation
Protects the
operating system
against failures of
commercial power
42
Operations Management Software
Protection
Protection
Monitoring
Monitoring
Diagnostics
Diagnostics
Management
Management
Remote
Remote
Easy control and cost efficiency assessment
43
Single Point Of
Failure
44
4. Extended Outage Protection
• High-Availability Electrical Power Provider
• On-Site Power Generation Capability
• 100% UPS Protection
• Extended Run UPS Electrical Power Provider
Backup Generator
IEEE Compliance GE Zenith Systems
Process Revenue
GE UPS IT Investment
45
Review: High Availability and Power
Protection
Power is #2 largest cause of system
downtime
Use the 5 step Business Process Availability Methodology:
Define process
Measure cost of downtime / process
Analyze data across process to achieve high availability
Improve process - standardize
Control process
Remember the 4 characteristics of high availability power solutions:
Solid electrical infrastructure
N+1 redundant UPS
Manageability
Extended outage protection
46
Redundant Architecture
Utility
Redundancy Protection should
Supply
be:
• Multiple units in parallel
• Any UPS should be able to be
the logic leader
• Decentralized bypass
• Redundant Communication
Bus
• Transparent failover and
recovery process
To critical
load
47
Don’t let Power
Outages, Harmonic
Distortion or any of the
Power Problems plague
your IT systems and
cripple your business.
Power Solutions
including UPS, TVSS,
Harmonic Cancellation
Transformers and state
of the art software
management tools for
complete PowerTrain
monitoring to protect
your critical data.
Power Failure Power Sag Power Surge Undervoltage Overvoltage Electrical Frequency Switching Harmonic
Line Noise Variation Transient Distortion
48
Power Black-out
If your
company had
been here,
would your
business
have been
protected?
• Power disturbances caused by faults / breakdown in Generation, Transmission & Distribution or End
User Electrical Distribution
• Frequency of events vary by geography… Generation Capacity, T&D Capacity, Weather, Acts of Nature
End User Grounding, Type of Loads
49
Thank You
Questions
50


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