Electrical Network Splitting Configuration

8/20/2019 Electrical Network Splitting Configuration

http://slidepdf.com/reader/full/electrical-network-splitting-configuration 1/121



CONTENTS



In a previous study

[1]Network Splitting was see to have potential for network fault level

reduction in the short term. From a fault level solution perspective it can offer significant faultlevel improvements, but in splitting a distribution network many important issues and factors

must also be considered.

This project is commissioned and managed by the DTI’s Distributed Generation Programme, andis guided by Workstream 3 of the Technical Steering Group. The focus of WS3 is on short-termnetwork solutions to help accommodate distributed generation.

A key element of this project is to understand and consider the performance of networks usingnetwork splitting arrangements. This in turn could help to accommodate distributed generationwhere perhaps fault level issues work against conventional generation connection arrangements.As mentioned before however, there are many issues to take into account and so network splittingshould not be construed as the immediate short term solution and answer for the connection of

distributed generation without also considering other important key issues.

This project is split into various tasks. These are:

1 Review impacts of network splitting2 Case study examples3 Network studies4 Other network issues5 Impact analysis6 Implementation of solutions

This report is structured into sections and cover these tasks in tern. This ensures a logical andstructured approach in documenting the work carried out under this project.



Network Splitting via a bus-section circuit breaker confirmed that fault levelscan be reduced significantly.

Concerns of quality of supply to the customer, and transient stability of the connected distributedgeneration, was suggested to be improved with the use of fast-closing switchgear or a statictransfer switch in the bus-section.

It was however expressed in this study that the fault level was seen to be sensitive to the closureof the normally open point (NOP) on the ring effectively connecting the cable network in parallelwith the bus-section breaker. It is suggested in [4] that care be taken in cases where short cablelength are present to ensure the network is operated in a radial configuration rather than as a ringas this can effectively eliminate any fault level benefits gained as a result of the open bus section.

Most HV networks however are operated as open rings. A particular issue is that it could bedifficult to move the open points on the open rings due to fault levels exceeding the networkcapability. During these periods it may be necessary to disconnect customers (i.e. make theparallels dead) but more likely is to require the DG to be constrained off for an hour or so whilstswitching takes place. This may, under fault conditions, be at short notice.



http://www.energywatch.org.uk/

http://www.energywatch.org.uk/



mailto:[email protected]

mailto:[email protected]

Electrical Network Splitting Configuration

Documents

Transcript of Electrical Network Splitting Configuration