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____________________________________________________________________________________
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Editorial Topic: Power Failure Causes and Remedies
Power Failures topic was main editorial issue in January. Unfortunately, power failures continue to be
main peoples concern also in February. We have recorded 42 major incidents in February, each
affecting thousands up to hundreds of thousands people. Taking in account the importance of this
subject on the Power Protection and UPS industry, we feel that that we should provide more insight,
focusing on this issue also in present News Letter.
To sense the agony that people feel when power fails, here are some reported reactions:
“We are in darkness, no lights, either in houses or the street. “
“There is no communication; we have been left without Internet and phones.”
“It is freezing, too, which is very worrying, because there are a lot of elderly people and small children
living on this estate.”
“No-one knew what was going on and everyone's worried about the money in their machines”
“Hotels and motels are filled up with residents seeking warm shelter.”
“My wife was trapped in the elevator; no one knows how to release her.”
“I spent hours on the road, in most places there are no traffic light signals.”
“Building supply stores are swamped with customers seeking generators and heaters”
These do not refer to business arena, where probably most harm was experienced.
Weather is generally held responsible for most of power outages. In numerous cases however,
significant damage is done by equipment malfunctions, revealed when the power fails. You can’t
blame acts of God when your battery, generator, switch or other critical item fails when it is called to
action.
Main power outages caused by weather are predictable, and do conservatively reappear year after year.
Generally, during the dry period, contamination which includes electrically conductive material, is
collected on power line insulators. Rains and storms close the electric path causing shorts and arcs,
tripping line breakers. Sometimes utility poles catch fire due to the electric arcs.
Salt is used in some areas as part of winter road treatment, increasing the amount of contamination
spread by road vehicles. This creates more potential for electric arcs near freeways and major roads.
Trees are also a leading cause of power failures in winter. Winds and snow cause trees to fall. The
falling trees cut power lines. Some power lines create electric shorts and arcs between adjacent power
lines or from power lines to ground.
Excessive heat, as experienced in Australia last months, overloads electricity supply due to tremendous
growth in air conditioning, thus tripping line breakers. Fires and high ambient temperature cause line
transformer malfunctions.
Lack of rain may affect power supply in places where considerable amount of power is generated by
hydropower. Kathmandu is now seeing severe power cuts, with no rain in the past few months and
decreasing water level in rivers feeding the hydropower plants.
The said 34 power fail incidents happened, according to reports, due to following reasons.
1. 7 Incidents (16.7%) -Transmission Line failure:
2. 7 Incidents (16.7%) -Transformer failure:
3. 5 Incidents (11.9%) - Unclear reason:
4. 5 Incidents (11.9%) - Backup generator failure
5. 3 Incidents (7.1% ) -Trees
6. 3 Incidents (7.1% ) - Underground Cable
7. 3 Incidents (7.1 %) - Car accidents
8. 2 Incidents (4.8% ) - Ice
9. 2 Incidents (4.8% ) - Air contamination
10. 1 Incident (2.4% ) - Equipment failure substation
11. 1 Incident (2.4% ) - No rain
12. 1 Incident (2.4% ) - Insulator mechanic failure
13. 1 Incident (2.4% ) - Turbine malfunction
15. 1 Incident (2.4% ) - No backup generator
Analyzing the results:
46 % of total incidents are caused by equipment failure. (Transformer, Underground cable, Substation
equipment, Insulator mechanic failure, Turbine malfunction, Backup generator, missing generator)
19% are caused by weather (Trees, Ice, No rain, Air contamination).
16 % Transmission Line failure , may or may not relate to natural cause.
12% Unclear reason.
7% Car accidents.
"Unclear" category, relates to incidents where the exact reason at the time of reporting was still
unknown.
Almost half of the reported incidents happen due to equipment failure. Most of these could probably
be avoided by proper preventive maintenance
The said failures concern grid distribution network that cause power outage lasting a few hours,
sometimes a few days. These might happen anywhere although the probability of failures is
considerably increased in certain locations, where at times of dramatic seasonal changes in
temperature, associated with strong winds and snow; citizens are plagued each year by electricity
problems.
Most public installations have backup generators, but these may obey Murphy’s Law, which, due to
poor preventive maintenance and/or lack of redundancy, fail to perform at the exact moment when
they are most needed.
UPSonNet’s Site News
News Briefs
In January 2009 we started a new service by presenting on our site Daily News Briefs. This service
aims to update users and Industry participants, with Essential Industry News, while investing only a
few minutes a day.
Our records indicate high interest in this service. Each day more people pay us daily visits to become
updated with the latest industry news.
The scope of interest varies according to the diverse interest of our audience. We had doubts before
deciding to present a more broad view, by including also such topics as financial results from Industry
partners, or agreements between Industries Partners.
Another issue of concern refers to inclusion Industry partners, that relate only partly to our reader’s
interests, such as Enersys, which offers also automotive batteries influencing considerable its financial
results.
We welcome any remarks, ideas or proposals from readers of this newsletter.
Please e-mail on any related subject to: info.newsletter@upsonnet.com
Industry News
Silicon Carbide (Sic) components
February News briefs, present new products from three companies based on SiC technology, offering
dramatic reduction in power conversion losses, and reduced size.
Infenion technology offers SiC based Shottky diodes claiming to reduce total converter losses by 20%.
Crey and Powerex demonstrate new SiC based dual switch module, claimed to reduce losses by 45%
compared to IGBT module.
Mitsubishi demonstrates 11kW inverter based on SiC diodes and Mosfet switching, claimed to reduce
total inverter losses by 70% and volume by 25%.
In the past the cost of SiC devices was the major consideration hampering its application. Now, due to
increased concern about energy waste and technological advancements, SiC becomes an interesting
cost effective solution.
Silicon Carbid is therefore now drawing attention as a next-generation material that comes after
Silicon. It’s excellent dielectric constant ten times greater than Silicon, enables reduction of
component thickness, associated with lower on–resistance and capacitance. Thus both conduction
and switching losses can be dramatically reduces. In addition compactness can be further increased
due to SiC's ability to oprate at junction temperatures of 200C , versus a limit of 150C for Silicon
IGBT's.
The importance of significantly decreasing both losses and volume cannot be exaggerated. It can be
compared to other revolutionary milestones which changed the power conversion industry, all by
introducing technologies which offered lower losses at less space. These include decreasing volume
and increasing efficiency by introduction of Transformerless UPS systems, Decreasing size and losses
of magnetic components while increasing Switching Frequency by means of IGBT components, and
additional striking frequency increase by introducing Resonant Converter circuits.
If economically justified, the new SiC components will cause an Industry Leap, enabling dramatic
decrease of volume and cooling requirements, of particular importance in data centers. The added
values, such as lower electricity costs, smaller batteries, more environment friendly systems are also
of prime importance.
To receive this newsletter in your e-mail please subscribe
Power Failures topic was main editorial issue in January. Unfortunately, power failures continue to be
main peoples concern also in February. We have recorded 42 major incidents in February, each
affecting thousands up to hundreds of thousands people. Taking in account the importance of this
subject on the Power Protection and UPS industry, we feel that that we should provide more insight,
focusing on this issue also in present News Letter.
To sense the agony that people feel when power fails, here are some reported reactions:
“We are in darkness, no lights, either in houses or the street. “
“There is no communication; we have been left without Internet and phones.”
“It is freezing, too, which is very worrying, because there are a lot of elderly people and small children
living on this estate.”
“No-one knew what was going on and everyone's worried about the money in their machines”
“Hotels and motels are filled up with residents seeking warm shelter.”
“My wife was trapped in the elevator; no one knows how to release her.”
“I spent hours on the road, in most places there are no traffic light signals.”
“Building supply stores are swamped with customers seeking generators and heaters”
These do not refer to business arena, where probably most harm was experienced.
Weather is generally held responsible for most of power outages. In numerous cases however,
significant damage is done by equipment malfunctions, revealed when the power fails. You can’t
blame acts of God when your battery, generator, switch or other critical item fails when it is called to
action.
Main power outages caused by weather are predictable, and do conservatively reappear year after year.
Generally, during the dry period, contamination which includes electrically conductive material, is
collected on power line insulators. Rains and storms close the electric path causing shorts and arcs,
tripping line breakers. Sometimes utility poles catch fire due to the electric arcs.
Salt is used in some areas as part of winter road treatment, increasing the amount of contamination
spread by road vehicles. This creates more potential for electric arcs near freeways and major roads.
Trees are also a leading cause of power failures in winter. Winds and snow cause trees to fall. The
falling trees cut power lines. Some power lines create electric shorts and arcs between adjacent power
lines or from power lines to ground.
Excessive heat, as experienced in Australia last months, overloads electricity supply due to tremendous
growth in air conditioning, thus tripping line breakers. Fires and high ambient temperature cause line
transformer malfunctions.
Lack of rain may affect power supply in places where considerable amount of power is generated by
hydropower. Kathmandu is now seeing severe power cuts, with no rain in the past few months and
decreasing water level in rivers feeding the hydropower plants.
The said 34 power fail incidents happened, according to reports, due to following reasons.
1. 7 Incidents (16.7%) -Transmission Line failure:
2. 7 Incidents (16.7%) -Transformer failure:
3. 5 Incidents (11.9%) - Unclear reason:
4. 5 Incidents (11.9%) - Backup generator failure
5. 3 Incidents (7.1% ) -Trees
6. 3 Incidents (7.1% ) - Underground Cable
7. 3 Incidents (7.1 %) - Car accidents
8. 2 Incidents (4.8% ) - Ice
9. 2 Incidents (4.8% ) - Air contamination
10. 1 Incident (2.4% ) - Equipment failure substation
11. 1 Incident (2.4% ) - No rain
12. 1 Incident (2.4% ) - Insulator mechanic failure
13. 1 Incident (2.4% ) - Turbine malfunction
15. 1 Incident (2.4% ) - No backup generator
Analyzing the results:
46 % of total incidents are caused by equipment failure. (Transformer, Underground cable, Substation
equipment, Insulator mechanic failure, Turbine malfunction, Backup generator, missing generator)
19% are caused by weather (Trees, Ice, No rain, Air contamination).
16 % Transmission Line failure , may or may not relate to natural cause.
12% Unclear reason.
7% Car accidents.
"Unclear" category, relates to incidents where the exact reason at the time of reporting was still
unknown.
Almost half of the reported incidents happen due to equipment failure. Most of these could probably
be avoided by proper preventive maintenance
The said failures concern grid distribution network that cause power outage lasting a few hours,
sometimes a few days. These might happen anywhere although the probability of failures is
considerably increased in certain locations, where at times of dramatic seasonal changes in
temperature, associated with strong winds and snow; citizens are plagued each year by electricity
problems.
Most public installations have backup generators, but these may obey Murphy’s Law, which, due to
poor preventive maintenance and/or lack of redundancy, fail to perform at the exact moment when
they are most needed.
UPSonNet’s Site News
News Briefs
In January 2009 we started a new service by presenting on our site Daily News Briefs. This service
aims to update users and Industry participants, with Essential Industry News, while investing only a
few minutes a day.
Our records indicate high interest in this service. Each day more people pay us daily visits to become
updated with the latest industry news.
The scope of interest varies according to the diverse interest of our audience. We had doubts before
deciding to present a more broad view, by including also such topics as financial results from Industry
partners, or agreements between Industries Partners.
Another issue of concern refers to inclusion Industry partners, that relate only partly to our reader’s
interests, such as Enersys, which offers also automotive batteries influencing considerable its financial
results.
We welcome any remarks, ideas or proposals from readers of this newsletter.
Please e-mail on any related subject to: info.newsletter@upsonnet.com
Industry News
Silicon Carbide (Sic) components
February News briefs, present new products from three companies based on SiC technology, offering
dramatic reduction in power conversion losses, and reduced size.
Infenion technology offers SiC based Shottky diodes claiming to reduce total converter losses by 20%.
Crey and Powerex demonstrate new SiC based dual switch module, claimed to reduce losses by 45%
compared to IGBT module.
Mitsubishi demonstrates 11kW inverter based on SiC diodes and Mosfet switching, claimed to reduce
total inverter losses by 70% and volume by 25%.
In the past the cost of SiC devices was the major consideration hampering its application. Now, due to
increased concern about energy waste and technological advancements, SiC becomes an interesting
cost effective solution.
Silicon Carbid is therefore now drawing attention as a next-generation material that comes after
Silicon. It’s excellent dielectric constant ten times greater than Silicon, enables reduction of
component thickness, associated with lower on–resistance and capacitance. Thus both conduction
and switching losses can be dramatically reduces. In addition compactness can be further increased
due to SiC's ability to oprate at junction temperatures of 200C , versus a limit of 150C for Silicon
IGBT's.
The importance of significantly decreasing both losses and volume cannot be exaggerated. It can be
compared to other revolutionary milestones which changed the power conversion industry, all by
introducing technologies which offered lower losses at less space. These include decreasing volume
and increasing efficiency by introduction of Transformerless UPS systems, Decreasing size and losses
of magnetic components while increasing Switching Frequency by means of IGBT components, and
additional striking frequency increase by introducing Resonant Converter circuits.
If economically justified, the new SiC components will cause an Industry Leap, enabling dramatic
decrease of volume and cooling requirements, of particular importance in data centers. The added
values, such as lower electricity costs, smaller batteries, more environment friendly systems are also
of prime importance.
To receive this newsletter in your e-mail please subscribe
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 |
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 |
| |
 |
| UPSonNet NewsLetter February 2009 |