ISAP 99 - DUtrain GmbH

which are suggested to the operator step by step)
is:
• isolating and grounding of defective 110 kV
cable OST-SUED2; due to the non-functioning
busselector in bay OST the busbar
sectionalizer in SUED2 must be opened;
• re-energization of left part of busbar in SUED2
from SUED1, partial recovery of 10 kV loads;
• recognition that the second transformer in
SUED2 cannot be fed from 110 kV, therefore
similar proceeding on 10 kV level as described
in scenario 3.
The given examples prove that the generic
restoration system is able to interactively provide
meaningful restoration suggestions for various
disturbance scenarios (each relying on the actual
system status), and if needed extending its
operations to all levels of the system which are
controlled from the actual control center or
represented on the simulator respectively. Current
work is to also verify the restoration system with
other power systems (e.g., the complete Dutch
400/230/150/110 kV transmission system).
4. CLOSED LOOP OPERATION
In case of operating remotely controlled
switchgear as well as setpoint assignment to
units, the restoration system can arbitrarily be set
into the autonomous operational mode as
described in [11] and [9]. The result is that the
number of necessary operator’s interventions is
drastically reduced, thus considerably speeding up
the process of restoration. Currently also an
intelligent automated selection of loads to be
reconnected, of units to be involved and of
topological connections to be preferred is under
development, leading to another significant step
towards closed loop system operation. Even if the
practical involvement of such grade of automatism
is still under critical discussion [12], the simulator
integration enables operators to smoothly become
acquainted with their functionality and developers
to test them in multifarious manner.
5. CONCLUSION
Restoration is one of the most demanding tasks in
power system operation. Due to rare occurrence,
lack of operators’ experience, time pressure and
stress, the involvement of technical systems for
either on line support or preventive training is
desired; but few approaches being practically
employed so far are mainly individual power
system specific solutions. The generic restoration
guidance system reported here overcomes this
drawback, taking over the characteristics of an
EMS application function. Combination with an
operators’ training simulator ensures that the
restoration performance can be verified in much
detail under various conditions - for which several
examples were reported -, and furthermore proves
as a powerful instrument for guided operators
training in disturbance clearing. Finally, the
potential of closed loop operation of such systems
can critically be estimated.
REFERENCES
[1] Proceedings of ESAP I - IV and ISAP 1994, 1996, 1997
[2] The Use of Expert Systems for Power System Restoration;
CIGRE Task Force 38.06.04, CIGRE-Brochure No. 90, 1994
[3] Spanel,U.; Krost,G.: System Restoration Guidance as
Intelligent Application Function in Power System Control;
submitted for ISAP 1999, Rio de Janeiro (Brazil)
[4] Spanel,U.; Krost,G.: Operator Training System - A Flexible
Approach; 12 th CEPSI, Pattaya (Thailand), 1998
[5] Rumpel,D.; Zaluk,R.; Post,U.: Concept of an On-line Data
Base supporting Grid Data Language, PSCC Lissabon
(Portugal), 1987, p. 345-351
[6] Rumpel,D.; Kempinski,W.; Litzinger,A.: Transparent Data and
Automatic User-Interface Design for Power-System Control
and Simulation, Proc. of the 31 st UPEC 1996, Iraklio
(Greece), Vol.2, pp. 372-375
[7] Dickers,K.; Rumpel,D.: Modelling for Grid Restoration
Studies, Electr. Power & Energy Systems, Vol.9, No.1, 1987,
p. 45-55
[8] König,S.; Mohr,L.; Krost,G.; Rumpel,D.; Spanel,U.: An Expert
System in Training Power System Restoration at the
Stadtwerke Duisburg AG; Intelligent Systems Application to
Power Systems (ISAP’94), Proc. Vol.2, Montpellier (France)
[9] Krost,G.; Spanel,U.: Heuristic Power Setpoint Assignment for
Restoration; Intelligent Systems Application to Power
Systems (ISAP’97), Seoul (Korea)
[10]Ju,K.; Krost,G.; Rumpel,D.: Expert System for Interlocking
and Sequence Switching; Intelligent Systems Application to
Power Systems (ISAP'96), Orlando (Florida)
[11]Krost,G.; Spanel,U.; Müller,Ch.: Self-acting Expert Systems
in Electric Energy System Operation; Intelligent Systems
Application to Power Systems (ISAP’96), Orlando (Florida)
[12] Panel Discussion on „Power Systems Control and Closed
Loop Action“; ISAP’96, Orlando (USA), 30.01.1996