Transcript Didden, M BE Session 2 – Block 3 Barcelona 12

Barcelona 12-15 May 2003
Considerations to choose the appropriate
voltage sag mitigation device
M. Didden, K.U.Leuven - Energy Institute
[email protected]
Didden, M BE Session 2 – Block 3
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Barcelona 12-15 May 2003
Introduction
- If process modifications are not possible, mitigation equipment
between process and grid can be considered
- General guideline before comparing different options:
f  p prev
Cinv
f
pprev
f·pprev
Csag
pmnt
i
n
Cinv

C sag
 (1  i)n (i  p
mnt )  p mnt

x
n

(
1

i
)
1





initial investment per kVA,
annual outages due to sags,
percentage of outages being prevented,
annual mitigated outages,
outage cost per sag per kVA,
annual maintenance costs per kVA as a percentage of Cinv,
discount factor,
project time (a).
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Barcelona 12-15 May 2003
Considerations (1/2)
Mitigation concept
1) Full protection: during a sag, the load is completely fed by an
external energy source
2) Relative protection: the voltage is raised by a certain
percentage, implying that the immunity of the equipment is
enhanced by the same percentage
3) Absolute protection: the process will be protected against sags
of a certain depth.
!!! It should be taken into account that the amount of reduced
process outages using this protection highly depends on the initial
immunity of the process
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Barcelona 12-15 May 2003
Considerations (2/2)
Price
- Initial purchase price
- Standby cost
- Maintenance (moving parts, batteries)
Other PQ-problems
Some applications are able to solve problems such as voltage
harmonics, current harmonics, flicker and controlling reactive
power.
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Barcelona 12-15 May 2003
Conclusions
The techno-economic best solution:
-
Flywheel
On-line UPS
DVR with energy reserve
DVR without energy reserve
Statcom
Shunt connected SM
Boost Converter
Active Front End
Transformerless series injector
Didden, M BE Session 2 – Block 3
/
if all sags have to be mitigated for
/
if no DC-bus
/
no DC-bus + other PQ issues
if DC-bus, no other PQ-issues
if DC-bus, other PQ-issues
no DC-bus, no other PQ-issues
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