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UNINTERRUPTIBLE POWER SUPPLIES

A N RAVAL ELECRICAL ENGINEER

CO(IS).IOCL

• THIS PRESENTATION IS FOR INFORMATIONAL AND THIS PRESENTATION IS FOR INFORMATIONAL AND EDUCATIONAL PURPOSES ONLY. IT DOES NOT CONTAIN EDUCATIONAL PURPOSES ONLY. IT DOES NOT CONTAIN ALL INFORMATION REQUIRED, AND IS NOT INTENDED TO ALL INFORMATION REQUIRED, AND IS NOT INTENDED TO BE USED FOR THE SPECIFICATION OR DESIGN OF BE USED FOR THE SPECIFICATION OR DESIGN OF UNINTERRUPTIBLE POWER SUPPLIES (UPS) OR UPS UNINTERRUPTIBLE POWER SUPPLIES (UPS) OR UPS SYSTEMS.SYSTEMS.

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INTRODUCTION

WHAT IS AN UNINTERRUPTIBLE POWER SUPPLY?WHY USE A UPS?

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WHAT IS AN UNINTERRUPTIBLE POWER SUPPLY?

AN UNINTERRUPTIBLE POWER SUPPLY (UPS) IS A DEVICE THAT HAS AN ALTERNATE SOURCE OF ENERGY THAT CAN PROVIDE POWER WHEN THE PRIMARY POWER SOURCE IS TEMPORARILY DISABLED

THE SWITCHOVER TIME MUST BE SMALL ENOUGH TO NOT CAUSE A DISRUPTION IN THE OPERATION OF THE LOADS

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WHY USE A UPS?

PROTECTS AGAINST MULTIPLE TYPES OF POWER DISTURBANCES

ONLY DEVICE THAT PROTECTS AGAINST AN OUTAGEOFFERS PROTECTION AGAINST

EQUIPMENT NOT OPERATING PROPERLY COMPUTER AND EQUIPMENT DAMAGE DATA LOSS TIME AND EXPENSE TO RECOVER BACK TO WHERE

YOU WERE, IF EVEN POSSIBLE

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POWER DISTURBANCES

CAUSESTYPESDURATIONRESULTING PROBLEMSCOMMENTSWHAT THE POWER UTILITY CAN DOWHAT THE ORIGINAL EQUIPMENT MANUFACTURER

(OEM) CAN DOWHAT YOU CAN DOPROTECTIVE DEVICES

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CAUSES OF POWER DISTURBANCES

STORM ACTIVITY – LIGHTNING, WIND, ICEOBJECTS COMING IN CONTACT WITH POWER LINE AND

TRIPPING BREAKER – TREE BRANCHES, ANIMALS, OTHER

CONSTRUCTION ACTIVITYACCIDENTS – MOTOR VEHICLE, OTHEREQUIPMENT FAILUREOVERLOADINGLOAD SWITCHINGPOOR GROUNDING

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TYPES OF POWER DISTURBANCES

INTERRUPTIONSAG, UNDER VOLTAGESURGE, OVER VOLTAGEVOLTAGE FLUCTUATIONFREQUENCY VARIATIONSPIKES / TRANSIENTS

IMPULSIVE OSCILLATORY

WAVEFORM DISTORTION DC OFFSET HARMONICS INTERHARMONICS NOTCHING NOISE

VOLTAGE IMBALANCE

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DURATION OF POWER DISTURBANCES

INSTANTANEOUS - ½ CYCLE (8 1/3 ms) OR LESSMOMENTARY - ½ CYCLE TO 3 SECTEMPORARY - 3 SEC TO 1 MINSUSTAINED - GREATER THAN 1 MINUTE

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PROBLEMS RESULTING FROMPOWER DISTURBANCES DATA ERRORS DATA LOSS BLOWN FUSES TRIPPED BREAKERS INTERFERENCE WITH CONTROL OF LOADS OVERLOADED NEUTRAL CONDUCTORS MOTORS

HEATING SPEED VARIATION STALLING AUDIBLE NOISE VIBRATION

TRANSFORMERS HEATING AUDIBLE NOISE VIBRATION

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POWER DISTURBANCESANDPROTECTIVE DEVICES

SURGE PROTECTOR

LINE FILTER ISOLATION TRANSFORMER

VOLTAGE REGULATING

LINE CONDITIONER

ON-LINE UPS

INTERRUPTION YESSAG, UNDER VOLTAGE YES YES

SURGE, OVER VOLTAGE YES YESVOLTAGE FLUCTUATION YES YESFREQUENCY VARIATION YES

IMPULSIVE YES YES YESOSCILLATORY YES YES YES

DC OFFSET YES YESHARMONICS YES YES

INTERHARMONICS YESNOTCHING YES YES

NOISE YES YES YESVOLTAGE IMBALANCE YES

PROTECTIVE DEVICE OFFER PROTECTION?

WAVEFORM DISTORTION

SPIKES / TRANSIENTS

POWER DISTURBANCE

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UPS

ARCHITECTURESWAVEFORMS INVERTER TECHNOLOGYCOMPONENTSSWITCHOVER TIMEADVANTAGES / DIS-ADVANTAGESSIZINGBATTERY SAFETY

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UPS COMPONENTS

CONVERTER - AC TO DC SPD - PROTECTS AGAINST SPIKES AND TRANSIENTS

BATTERY STORED ENERGY DEVICE - PROTECTS AGAINST INTERRUPTIONS

INVERTER – DC TO AC WAVEFORM SYNTHESIS – PROTECTS AGAINST DC OFFSET AND

INTERHARMONICS FILTER – PROTECTS AGAINST HARMONICS, NOTCHING AND NOISE VOLTAGE REGULATOR – PROTECTS AGAINST SAGS, SURGES AND

FLUCTUATIONS

MONITOR AND CONTROL HARDWARE / SOFTWARE

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SWITCHOVER TIME

A TYPICAL SWITCHOVER TIME 2 – 4 ms

ONE QUARTER CYCLE OR LESS

FOR SOME EQUIPMENT THIS IS NOT TOLERABLE

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BLOCK DIAGRAMLINE INTERACTIVE UPS

BATTERY CHARGER

AC SUPPLY

INVERTERDC TO AC

CRITICALLOAD

(AC)

BATTERY

AUTOMATIC SWITCH

AC FAIL

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BLOCK DIAGRAMON-LINE UPS

CONVERTER AC TO DC

AC SUPPLY

INVERTERDC TO AC

CRITICALLOAD

(AC)

BATTERY

AUTOMATIC SWITCH

INVERTER FAIL

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UPS WAVEFORMS

TRUE SINEWAVEMODIFIED SINEWAVESQUARE WAVE

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UPS WAVEFORMS

-170

0

170

0 4 8 12 16 20

TIME (ms)

VO

LT

AG

E

TRUE SINEWAVEMODIFIED SINEWAVESQUARE WAVE

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INVERTER TECHNOLOGY FOR TRUE SINEWAVE

PULSE WIDTH MODULATION - PWMLINEAR AMPLIFIERRESONANT INVERTER

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BLOCK DIAGRAMPWM INVERTER

HIGH FREQUENCY GENERATOR

PULSE WIDTH MODULATOR

BASE / GATE DRIVE

TRANSISTOR BRIDGE

TRANSFORMER FILTER

CRITICALLOAD

(AC)

REFERENCE SINEWAVE

GENERATORCOMPARISON

AMPLIFIER

DC POWER

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BLOCK DIAGRAMRESONANT INVERTER

SQUARE WAVE

GENERATOR

SWITCH DRIVE

TRANSISTOR SWITCHES

TRANSFORMERLC RESONANT TANK FILTER

CRITICALLOAD

(AC)

DC POWER

(OR FERRORESONANT)

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ADVANTAGES / DIS-ADVANTAGES OF THE DIFFERENT UPS ARCHITECTURES

LINE INTERACTIVE ADVANTAGES AC TO DC CONVERTER / BATTERY CHARGER DOES NOT HAVE TO

PROVIDE FULL LOAD POWER (POTENTIALLY CHEAPER) LESS STRESS ON DC TO AC INVERTER SINCE IT RUNS AT NO LOAD

UNTIL UPS SWITCHES TO BATTERY POWER (POTENTIALLY CHEAPER)

ON-LINE ADVANTAGES ZERO SWITCHOVER TIME FROM MAIN LINE TO BATTERY POWER ALWAYS ISOLATED FROM POWER DISTURBANCES ON THE MAIN

LINE

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SIZING THE UPS

EQUIPMENT RATINGS FOR LOADS OBTAIN RATINGS FROM NAMEPLATE OR SPEC SHEET ENERGY USAGE MAY BE SPECIFIED IN VOLT AMPS (VA) OR WATTS

(W) AND IN VALUES THAT ARE EITHER MAXIMUM OR NOMINAL (VA) AND (W) ARE RELATED VIA THE POWER FACTOR

TOTAL UPS LOAD MUST NOT EXCEED THE UPS VOLT AMP (VA) RATING

TOTAL UPS LOAD MUST NOT EXCEED THE UPS WATT (W) RATING

OVERSIZE / DERATE TO ADD LIFE

RUNTIME CHARTS

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BATTERY SAFETY

MAINTENANCE INSPECT PERIODICALLY REPLACE AS NEEDED

RISKS ACID ELECTRIC SHOCK BURN FLYING, MOLTEN METAL (EYES) INJURIES RESULTING FROM CARRYING HEAVY BATTERY PACKS

DISPOSAL DISPOSE OF PROPERLY RECYCLE WHENEVER POSSIBLE

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DOES A UPS OFFER COMPLETE PROTECTION?

SOME POWER DISTURBANCES MAY EXCEED THE HANDLING CAPABILITY OF THE UPS

UPS FAILURE

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DO YOU THINK “POWER DISTURBANCES WON’T HAPPEN TO YOU” ?

POWER DISTURBANCES OCCUR FREQUENTLY, THOUGH MANY ARE SMALL AND WITHOUT CONSEQUENCE

AN ON-LINE UPS CAN PROTECT AGAINST MORE SIGNIFICANT POWER DISTURBANCES WHEN THEY DO OCCUR

THE COST OF NOT HAVING A UPS CAN EASILY EXCEED THE COST OF A UPS

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SUMMARYTHINGS TO CONSIDER WHEN SPECIFYING A UPS

POWER QUALITY ARCHITECTURE - LINE INTERACTIVE OR ON-LINE WAVEFORM - SQUARE, MODIFIED SINE, TRUE SINE IMMUNITY TO DISTURBANCES OTHER THAN OUTAGE

RUN TIME WITH AN OUTAGERELIABILITYAUDIBLE NOISEMONITOR AND CONTROL HARDWARE / SOFTWARE

LOCAL / REMOTE CONTROL

INITIAL COSTMAINTENANCE COSTWARRANTY

AN RAVAL