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Enhanced Reliability

Main Features

The new Reliability module is an optional facility within DINIS and offers many enhancements over the reliability facility that comes as part of the standard Core DINIS application. Specifically the new Reliability module has been developed to provide meaningful information from actual data gathered across a network with emphasis on the customer and restoration times. The results will give a quantitative measure of the reliability of the network and the effectiveness of the current network protection.

The objective for the Reliability module is to enable users who have databases, which contain information on line and plant failures or maintenance records, to enter this information into DINIS networks in direct form. From this input, DINIS will calculate the internationally accepted performance and reliability statistics for any circuit including nested protection areas, and offer all the DINIS inter-active graphic and "what-if" analysis facilities.

Provides for time scales to be measured terms of “time periods”. This will greater flexibility and benefit users who do not record their maintenance or reliability over one calendar year or over a 12-month period.
Take account of the number of faults occurring on each line per time period. This can make use of historical data which has been recorded for a particular time period, grouped data to find an average over a number of time periods or projected values from activity curves to give the predicted number of faults, which will occur on a specific line, for a time period in the future.
Calculate the faults per time period for loads, transformers and shunts. Again, the data can be historic, an average or predicted and the number of faults per time period
Allow the user to select whether switching will restore loads or whether the fault must be repaired for supply to be restored. These two different methods of restoring supply will have two different associated supply restoration times which will be stored in the data for the protection device.
Calculate a number of “reliability indices”. These indices are calculated from formulae that typically include the number of interruptions, the duration of interruptions and the number of customers affected. There are over ten of these reliability indices. The Reliability module will calculate the four most common of these indices, which are:
o System average interruption frequency index (SAIFI).
o System average interruption duration index (SAIDI).
o Customer average interruption duration index (CAIDI).
o Average service availability index (ASAI).
Historical or predicted indices can be calculated depending on the data available. Actual records can be used to calculate indices for previous time periods, or predicted faults on the network can be used to calculate indices for future time periods. A description for the type of information may be entered and later displayed with the results. There are several advantages of entering data for different time periods:
o Using historical data for different time periods can build up a picture of chronological changes to the network to identify weak areas.
o Existing indices can be established which can act as a guide for acceptable levels in the future.
o Previous predictions can be compared with actual performance. This will give a true gauge of the accuracy of the simulated results.
o Use of predicted data in conjunction with maintenance schedules can be used to re-plan maintenance activities and effect cost savings.
As mentioned above, the loads will contain information regarding how their supply will be restored i.e. by switching or repair. It is the intention that the circuit will be configured to calculate indices for specific situations. Further to this, indices will be calculated by assuming that all the loads will be restored by switching (best case scenario) and all the loads will be restored by repair (worst case scenario).
The results of the indices will be available for both individual protection zones and the entire network, i.e. overall indices for all the protection zones in the network.
Allow the identification of areas of the network that require more protection and suggest areas where devices should be added. This will be in the form of a report and the actual network will remain unchanged. The report will identify the zone with the worst reliability indices and suggest a node in this zone where a further protection device should be placed in order to create a new zone containing 30% of the load for the original zone. The figure of 30% will be set as a system setting so that it may be changed.
Enable users to determine the impact of embedded generation on your network
The ability to define the cost to the consumer of loss of supply becomes possible through use of the Reliability module.
Enables you to assess the impact of distribution loss of supply on the energy supply (retail) companies, who are subsequently unable to deliver energy they have purchased.
The reliability module is API enabled. This will enable users to “drive” the module remotely or automatically as part of a reliability sequence by means of entering data into DINIS, running the analysis and generating the output results.

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