UPS

1. UNINTERRUPTIBLEUNINTERRUPTIBLE
POWER SUPPLIES( UPS)POWER SUPPLIES( UPS)

2. UNINTERRUPTIBLE POWER SUPPLIESUNINTERRUPTIBLE POWER SUPPLIES
OUTLINEOUTLINE
• INTRODUCTION
• UNINTERRUPTIBLE POWER SUPPLIES
• GENERAL DISCUSSION
• SUMMARY

3. INTRODUCTIONINTRODUCTION
• PURPOSE
• WHAT IS AN UNINTERRUPTIBLE
POWER SUPPLY?
• WHY USE A UPS?

4. PURPOSEPURPOSE
• THE PURPOSE OF THIS PRESENTATION IS TO DISCUSS THE
DIFFERENT TYPES OF UNINTERRUPTIBLE POWER SUPPLIES
AVAILABLE, WHAT THE UPS PROTECTS AGAINST, THE
COMPONENTS OF A UPS, AND ISSUES REGARDING SELECTION AND
SIZING.
• THE DIFFERENT TYPES AND CAUSES OF POWER DISTURBANCES
ARE DISCUSSED, AS WELL AS WHAT THE POWER UTILITY, THE
ORIGINAL EQUIPMENT MANUFACTURER, AND YOU, CAN DO TO
MINIMIZE THEIR EFFECT.

5. WHAT IS AN UNINTERRUPTIBLE POWERWHAT IS AN UNINTERRUPTIBLE POWER
SUPPLY?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

6. WHY USE A UPS?WHY USE A UPS?
• PROTECTS AGAINST MULTIPLE TYPES OF POWER
DISTURBANCES
• ONLY DEVICE THAT PROTECTS AGAINST AN OUTAGE
• OFFERS 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

7. UPSUPS
• ARCHITECTURES
• WAVEFORMS
• INVERTER TECHNOLOGY
• COMPONENTS
• SWITCHOVER TIME
• ADVANTAGES / DIS-ADVANTAGES
• SIZING
• BATTERY SAFETY

8. UPS ARCHITECTURESUPS ARCHITECTURES
• LINE INTERACTIVE
• ON-LINE

9. BLOCK DIAGRAMBLOCK DIAGRAM
LINE INTERACTIVE UPSLINE INTERACTIVE UPS
BATTERY
CHARGER
AC SUPPLY
INVERTER
DC TO AC
CRITICAL
LOAD
(AC)
BATTERY
AUTOMATIC
SWITCH
AC FAIL

10. BLOCK DIAGRAMBLOCK DIAGRAM
ON-LINE UPSON-LINE UPS
CONVERTER
AC TO DC
AC SUPPLY
INVERTER
DC TO AC
CRITICAL
LOAD
(AC)
BATTERY
AUTOMATIC
SWITCH
INVERTER FAIL

11. BLOCK DIAGRAMBLOCK DIAGRAM
LAPTOP COMPUTER POWER SUPPLYLAPTOP COMPUTER POWER SUPPLY
CONVERTER
AC TO DC
AC SUPPLY
CONVERTER
DC TO DC
BATTERY
CRITICAL
LOAD
(DC)

12. UPS WAVEFORMSUPS WAVEFORMS
• TRUE SINEWAVE
• MODIFIED SINEWAVE
• SQUARE WAVE

13. UPS WAVEFORMSUPS WAVEFORMS
-170
0
170
0 4 8 12 16 20
TIME (ms)
VOLTAGE
TRUE SINEWAVE
MODIFIED SINEWAVE
SQUARE WAVE

14. INVERTER TECHNOLOGY FOR TRUEINVERTER TECHNOLOGY FOR TRUE
SINEWAVESINEWAVE
• PULSE WIDTH MODULATION - PWM
• LINEAR AMPLIFIER
• RESONANT INVERTER

15. BLOCK DIAGRAMBLOCK DIAGRAM
PWM INVERTERPWM INVERTER
HIGH
FREQUENCY
GENERATOR
PULSE WIDTH
MODULATOR
BASE /
GATE
DRIVE
TRANSISTOR
BRIDGE
TRANSFORMER FILTER
CRITICAL
LOAD
(AC)
REFERENCE
SINEWAVE
GENERATOR
COMPARISON
AMPLIFIER
DC POWER

16. BLOCK DIAGRAMBLOCK DIAGRAM
LINEAR AMPLIFER INVERTERLINEAR AMPLIFER INVERTER
OSCILLATOR
AMPLIFIER
SINEWAVE
OSCILLATOR
TRANSFORMER
COMPARISON
AMPLIFIER
POWER
AMPLIFIER
CRITICAL
LOAD
(AC)
DC POWER

17. BLOCK DIAGRAMBLOCK DIAGRAM
RESONANT INVERTERRESONANT INVERTER
SQUARE
WAVE
GENERATOR
SWITCH
DRIVE
TRANSISTOR
SWITCHES
TRANSFORMER
LC RESONANT
TANK FILTER
CRITICAL
LOAD
(AC)
DC POWER
(OR FERRORESONANT)

18. UPS COMPONENTSUPS 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

19. SWITCHOVER TIMESWITCHOVER TIME
• A TYPICAL SWITCHOVER TIME 2 – 4 ms
• ONE QUARTER CYCLE OR LE
• FOR SOME EQUIPMENT THIS IS NOT TOLERABLE

20. ADVANTAGES / DIS-ADVANTAGES OFADVANTAGES / DIS-ADVANTAGES OF
THE DIFFERENT UPS ARCHITECTURESTHE 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

21. BATTERY SAFETYBATTERY 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

22. GENERAL DISCUSSIONGENERAL DISCUSSION
• DOES A UPS OFFER COMPLETE
PROTECTION?
• DO YOU THINK “POWER
DISTURBANCES WON’T HAPPEN TO
YOU” ?
• MISCELLANEOUS

23. SUMMARY
THINGS 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 OUTAGE
• RELIABILITY
• AUDIBLE NOISE
• MONITOR AND CONTROL HARDWARE / SOFTWARE
LOCAL / REMOTE CONTROL
• INITIAL COST
• MAINTENANCE COST
• WARRANTY