Sergiu Paduraru, CIGRE meeting Rio de Janeiro, 6 – 7 of April 2010
Latest trends in PMUs and Wide Area Systems
© ABB Group
April 12, 2010 | Slide 1
Content
ƒ
C37.118 standard developments – PMU performance – related developments
ƒ
C37.118 standard developments – standard philosophy – related developments
ƒ
Towards a new time synchronization concept – the evolution of IEEE 1588
standard
ƒ
PDC requirements – do we need to define a PDC-to-PDC communication
protocol?
ƒ
PDC requirements – do we need to have performance requirements in a
standard?
ƒ
Comments and Questions
© ABB Group
April 12, 2010 | Slide 2
C37.118 standard developments
PMU performance – related developments
ƒ
The specification of the dynamic requirements is finalized right now by the
standard working group and should come out soon.
ƒ
A special attention is given to frequency requirements and the compromise
between
- the response time of the device, and
- the artifacts outside the bandwidth.
ƒ
A new type of requirement – related to the faster reporting frequency was gaining
more and more adherents in the NASPI meeting in February in Austin and the
iPCGRID meeting in March; more and more people would like to have reporting
rates of 120 msg/sec. or even 240 msg/sec; the possible applications extent is not
apparent right now.
ƒ
ABB will include all the new standard requirements in the new PMU product,
scheduled to hit the market in 2011, and will implement also those requirements
that are favored by the community, but will not be standardized by that time.
© ABB Group
April 12, 2010 | Slide 3
C37.118 standard developments
standard philosophy – related developments
ƒ
At the end of March a ”YES” vote was given by the standard working group to split
the standard into two parts:
- C37.118-1 for the device performance requirements
- C37.118-2 for the communication protocol
ƒ
This split has a number of advantages, one of them is that it prepares the field for
the merging with the IEC61850 standard – and the development of the new
IEC61850-90-5 standard
ƒ
There are a number of pitfalls to be avoided in the new standard, like – for
example – how the integration of phasor data transmission requirements will affect
the already existing requirements in this area (in the 9-2 part of the standard) but a
careful development will make it possible to avoid these pitfalls
ƒ
ABB participates actively in the development of the new IEC61850-90-5 standard
and will incorporate all the new requirements stemming from it in the new products
© ABB Group
April 12, 2010 | Slide 4
Towards a new time synchronization concept
The evolution of IEEE 1588 standard
ƒ
For quite a time now, the most precise time synchronization has been the one
given by GPS; while it’s accurate, it has the disadvantage of a non-standardized
time distribution concept – if a substation is having a number of devices
synchronized by GPS, one ends up in a situation where it either has a ”forest” of
GPS antennas or it’s distributing the signal through a non-standard system of
antenna splitters
ƒ
One can say that IEEE 1588 takes the SNTP concept to a new level – it can have
multiple master clocks, path delay calculation mechanisms and much more
ƒ
The ”end result” of the standard will have a performance of sub 1µs time accuracy
distributed over Ethernet networks
ƒ
ABB is in the spearhead of the IEEE 1588 standard development and will include
the 1588 type of time synch in the upcoming products
© ABB Group
April 12, 2010 | Slide 5
PDC requirements – are we in need to define
a PDC-to-PDC communication protocol?
ƒ
Right now the C37.118 is sufficient to serve the existing PDC-to-PDC
communications, but very soon it will become obvious that this will not be enough:
- PDCs will come in different ”flavors”, some of them – like for example the
gateway/PDC will be in need for an extended security implementation,
and that has no place in C37.118 right now;
- there are different types of PDC-to-PDC communication – some (like the
transmission of the actual data frames) can be performed by a specific
protocol (like C37.118), others (like database transfer, synchronization
and reconstruction) are better left to commercially available,
database specific protocols (like ODBC).
ƒ
C37.118-2 and IEC61850-90-5 will have to address these issues too, but the
difficult part will be to distinguish between different types of inter-PDC applications;
a diligent work must be done here.
ƒ
ABB has a strong PDC implementation that works seamlessly with our Network
Management Systems, and a development in this area is under way.
© ABB Group
April 12, 2010 | Slide 6
PDC requirements – do we need to have
performance requirements in a standard?
ƒ
Given a Wide Area System, we can say that the Phasor Data Concentrator is
the only device that operates outside a standard
ƒ
As we specified before, there are different types of PDCs:
- the ”substation PDC” – can be used as a data back-up PDC;
- the ”data server PDC” – that will store the data from the data stream
and make it available for the Wide Area Applications;
- the ”gateway PDC” – while the two types above are ”fishing” data from a
data stream in a switch, this one is an interconnection PDC (with other
WAS) with extended security functionality so the data is ”going through it”
- the ”super PDC”, a more complex version of the ”data server”;
all these have slightly different requirements
ƒ
We consider that we need a PDC standardization and ABB will support and
actively participate in such a standard
© ABB Group
April 12, 2010 | Slide 7
© ABB Group
April 12, 2010 | Slide 8