Products and Services

 

IPSI
P.O. Box 92384
Rochester, New York 14692
In the USA
Tel. 1.800.959.4724
Fax: 585.359.9061
Contact IPSI

International
Tel. +001-585-334-5803
Fax. +001-585-359-9061

   
 

Power Quality and Harmonic Abatement

 
  IPSI not only provides the services necessary to insure that your equipment receives power when needed, but also services to assure that the power you need is high quality.

With modern electronic controls, "reliable" power is not sufficient; you need "power quality" also.

Poor Power Quality can manifest itself in several different ways:

1. Sags or Swells (surge) - RMS voltage variations. A sag is usually defined as a decrease in the normal voltage supply level of 90% or less than the nominal RMS level. . This is the most common type of power quality issue. A swell/surge is defined as an increase in the normal voltage level of about 110%. Both Sags and swell last less than 3 minutes. Anything below 10% is in reality an "interruption."

 
 

 


 

Example of a Voltage Sag/Swell

 

 

 

 

Example of a Current Sag/Swell

   
  2. Dropouts- lose of voltage, normally short term event, normally lasting milliseconds or seconds.  
  Example of a Dropout    

 

3. Transients/Impulses - short-term excess voltage, normally measured in microseconds that result in a notched waveform

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Example of a Transient

 

4. Harmonics- Distortion of the normal voltage and current waveform that are integer multiples of the fundamental frequency. Interharmonics are non-interger multiples of the fundamental frequencies.

 

Example of voltage without harmonic distortion

Example of voltage without harmonic distortion

 

Example of harmonics over a one week period

 

5. Reliability- Power is not available when needed. These are long term events that can be measured in minutes, hours and days. This would include "rolling blackouts" and power outages.


The Results/consequences of power quality.

Blown Fuses & breakers

Overheated components - wiring, capacitors, motors, etc.

Erratic control functions

Damaged equipment

Telephone line buzz

Causes of Poor Power Quality

Non-linear loads, inc adjustable speed drives

Solid State controls - can cause damaging harmonic currents and voltages

Arc welders, furnaces

Power factor correction capacitors

Faulty power transformer

Poor connections, loose terminations or improper grounding

Utility capacitor switching

Solutions to Poor Power Quality

1st Step: A complete power quality analysis by IPSI trained engineers and technicians.

2nd Step: Implement a solution based on the power quality analysis:

Typical solutions:

Adding capacitors

Installing a back up generator set (Standby Generator Info)

Adding a ride thru UPS system (Vycon Flywheel System Info)

Installing special transformers

Installing harmonic trap filters (can be active or passive) (MTE Matrix Filter Info)

Using a phase shift transformer

Neutral conductor resizing

Repairing wiring and connections.

                                      

 

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     Site Created by Amy Pschierer