Web deploying an integrated GIS/SCADA/OMS solution
If disparate data from GIS and SCADA systems need to be integrated - how and
where is the best place to store the resulting single real-time ‘operational’ network
model? There are three main options.
Option 1 – Build the DMS within the SCADA
Option 2 – Build the DMS within the GIS
Option 3 (preferred option) – Build the DMS as an independent platform
Option 1 - Build the DMS within the SCADA system
In the early 1990’s the importing of GIS data into a real-time SCADA system had
been achieved and deployed in isolated projects. What this approach tended to do
however, was force the SCADA system to deviate from its original design
characteristics. Fundamentally, SCADA systems are designed with a purposely
sized database, very high-speed data event processing, high reliability and rather
simple graphical display functionality. The data volume associated with GIS
systems was substantially higher than that of typical SCADA systems and the
spatial data display requirements were considerably different to the rather basic
single line diagrams SCADA systems were designed to display. As a consequence,
compromises had to be made to achieve this architecture e.g. Simplification of the
network model.
Option 2 - Build the DMS within the GIS system
GIS systems were never originally designed or used as real-time operational tools.
GIS platforms were rarely deployed in such a manner as to guarantee 24 hour by 7
day availability with seamless failover. The primary function of GIS systems was
to store data, provide a set of tools to maintain the data and allow easy importing
and exporting of data to other systems. As the business need developed to integrate
real-time data with geographical data, GIS companies recognised this, and began
developing strategies to adapt their systems. This adaptation however proved to be
a far more complex exercise than anticipated. The system performance that was
required to effectively handle real-time dynamic data was difficult to achieve on a
platform that was never intended to perform such high throughput levels.
While significant steps have now been made by GIS companies, the guarantees of
24 by 7 availability and the ability to process real-time data at up to 200 events per
second for 10 or 20 seconds, as in the case of storm conditions, remain promises
that GIS companies are still reluctant to make.
Option 3 - Build the DMS as an independent platform
Deciding on a solution to the integration challenge begins with identifying sound
philosophical positions on which to base the decisions. The philosophies that the
majority of utility companies are adopting include choosing best of breed products,
utilising modular design techniques and allowing the ultimate business needs to
drive the technical architecture.
Given that SCADA has major limitations regarding its ability to display spatial
data, and GIS has inherent problems managing real-time data, it would appear that
neither option provides an optimal solution for the business. Both options involve
compromising the specialised nature of each system and impose limitations for the
future development of other business systems.
A logical conclusion would therefore be to integrate SCADA and GIS data on a
platform that can support both spatial and real-time data while providing the
necessary performance requirements. This platform would also provide the basis to
integrate other data and related technologies such as trouble call and customer
information. This allows the user to put in place an integration platform rather than
just a distribution management ‘product’. By utilising a modular design, the user
maintains the flexibility to choose best of breed products including trouble call,
dispatch, power analysis etc.
A complete DMS product therefore stands on its own merits as an integration
platform built to handle real-time and spatial data, with open interfaces to external
systems and a modular internal software structure. This solution guarantees that
current demands are met and future needs can be confidently accommodated by
simply building new modules and interfaces with the existing ‘open’ DMS
platform.
The DMS platform then provides the basis for specialist applications such as:
- Outage Management
- Switching Management
- Storm Management
- Power Analysis
- Load Management
Flexiblity is the key
By using an independent DMS, a utility is no longer bound to a particular GIS or
SCADA vendor. If the utility was to merge with a second utility with a different
GIS and SCADA system, the utility has the choice to either decommission systems
or simply provide another interface into the new GIS and SCADA systems.
This flexibility extends to the integration of other systems that may contribute data
to the operational network model e.g. Switch asset databases, land base maps etc.
By ensuring that the DMS has a modular internal architecture, the additions of new
software functionality can also be achieved at the minimum cost and risk. Utilities
may have no immediate need for Load Flow analysis, but may wish to add such
functionality in the years to come. The internal architecture of the ‘ideal’ DMS
then becomes:
- real-time data base (Operational network model)
- generic interfaces (GIS, SCADA etc)
- optional software modules (switching management, dynamic ratings etc)
A modular approach to Distribution Management Systems allows SCADA, GIS
and other external systems to live out their natural life-cycle and eventually be
replaced with products from any preferred vendor.
Step 2 - Web Enabling the DMS
There has been a great deal written about the power of web technologies, and how
‘eBusiness’ will transform business. By remaining true to the position that ‘the
business requirement should guide the technical solution’, there is the opportunity
to utilise web technologies in operational systems such as DMS. Care needs to be
taken however to ensure that all the business requirements are considered
including security, performance and functionality.
