Now you can be better prepared for circumstances of insufficient pressure or supply in your gas pipeline network.
- If pressure drops in the system how long can we keep our high priority customers in service?
- We have a zone with a major hospital and and other critical customers, what alternate zones can we shut in to keep them going?
- How can we be better prepared to operate the system with the minimal amount of disruption to the network in the event of an emergency?
- If we need to shut in Zone 1 which other zones may be impacted as well?
NextGen’s LoadPlanning Module will enable operators to proactively manage their pipeline networks when less than optimal conditions occur for delivering gas supplies to their customer base.
A low pressure situation can occur for any number of reasons, ranging from an unprecedented weather event, an accidental break in the line, the infrastructure’s inability to handle an increase in demand, or to a disruption due to a scheduled maintenance. It is clear that distribution companies need the ability to control and prioritize which loads can be preemptively suspended during low pressure conditions, as well as be made aware of which areas will be automatically shut in during a forced load shedding event.
Preemptive Load Planning is performed in a controlled manner where an absolute minimum number of meters get shut in and low pressure situations are proactively avoided in specified areas for as long as possible.
The LoadPlanning Module will allow the model to be split into isolation zones by defining a region for each isolation zone, and setting priorities so that some nodes (and all meters under them) will be shed before others, i.e., higher priority loads, such as zones with hospitals or contract priorities, can remain online for as long as possible and only get shut in after the lower priority zones have been sequentially shed. If multiple pressure isolated areas are being impacted by minimum delivery pressure violations, the program will keep repeating load shedding runs until all areas have been fixed.
A Forced Load Shedding on the other hand, is an uncontrolled and automatic occurrence resulting in deliveries unable to be made to the various nodes or meters, regardless of priority.
The program will attempt to shed loads in all areas of the system that are experiencing minimum delivery pressure violations, even if they are in totally separate pressure isolated regions of the system. The LoadPlanning Module will allow an operator to see the ramifications of a shut in if no preemptive measure have been taken.
The LoadPlanning Module will enable you to:
- Assign a load shedding Priority Level to each node and meter in the system (typically tied to a contract).
- Loads are then shed sequentially from lower priority nodes or meters to the next higher priority level.
- Intelligently shed the absolute minimum number of zones.
- Manually select which emergency isolation zone to shut in or re-enable in addition to the optimization algorithms selecting shut in zones.
- Exclude some nodes (and all meters under it) within a load shedding zone from load shedding.
- Define a search radius which will limit the loads shed within one priority level before going on to the next priority level.
- Make simulation runs to gauge how different combinations of shut down zones impact the system operation.
- Alert customers of impending cuts, be able to take corrective action.
- Use optimization algorithms to keep the amount of loads shed to an absolute minimum.
- Demonstrate justification as to why specific loads were shed in the event of legal action.
The Methodology
- The LoadPlanning Module uses optimization algorithms in tandem with steady state runs to predict which nodes and meters to shut in during low pressure conditions.
- A system can potentially be comprised of dozens, or even tens of thousands of nodes or meters to be shut in, and the LoadPlanning optimization logic works equally well regardless of the complexity of the network.
LoadPlanning Features
- Override Sequence Numbers are set by the user to control which nodes get shed first.
- In Forced Load Shedding Mode, the LoadPlanning Module will assist in predicting exactly which nodes or meters will be shut in due to low pressures when certain operating conditions are encountered.
- LoadPlanning Module can be used in Preemptive Load Planning Mode to determine exactly which nodes or meters to shut in beforehand to avoid the low pressure problems in the first place.
- Option of setting a limit at any particular node or meter so that rather than the entire load being cut to zero, only a portion of it is cut.
- No limit on the number of priority levels, or on how many nodes or meters can reside within each level.
