Meter assigned to the wrong substation: finding mapping errors
A balance group is a substation and all meters it supplies. If the records put a meter under one substation while it is actually connected to the neighbouring one, the imbalance of both is wrong. Such errors pile up over the years: switching, new connections, rerouted lines. GRID-IN uses AMI data to determine which substation each meter actually belongs to.
How does the error distort the imbalance?
The consumption of the “foreign” meter lands in the wrong sum:
- the substation the meter is wrongly assigned to has more metered than it supplied — its imbalance is too low or negative;
- the substation that actually supplies the meter misses its consumption — its imbalance is too high and looks like losses.
Why fix this first?
While the mapping is wrong, the substation imbalance shows a metering error, not losses. Crews go looking for irregularities where there are none, while real losses at the neighbouring substation go unnoticed. Checking on site means walking the lines, and diagrams go out of date just like the records.
What does GRID-IN do?
- no mapping available — builds it from the data: which meters belong to which substation;
- mapping available — checks it and lists, with addresses, the meters that according to the data belong to another substation;
- diagram available — shows mismatches between diagram and records: a meter on the diagram under another substation, a house on the map with no service connection on the diagram.
Once the mapping is fixed, each substation’s imbalance becomes real, and only then can losses be looked for in it.
What is needed?
Load profiles of consumer meters and of the substation input meters for the same period — for all substations between which errors are possible, i.e. neighbouring substations together. The existing mapping from the records, if any, to check it. Details — Data requirements.
Related pages: Substation imbalance, How to reduce losses in 0.4 kV networks.