Electrical distribution hierarchy for load management

[chuck-h]

OCA presents a model for electrical distribution hierarchy in OCPP2.0 "Standardized Components" 3.2.24, and gives an illustrative example at 3.2.41

An example. The incoming fuses are all 120A. Each floor has a set of 80A fuses. On
the first floor, there’s also a group of Charging Stations that are behind a set of 32A
fuses.
DistributionPanel.Fuse[1] = 120
DistributionPanel.Fuse[2] = 120
DistributionPanel.Fuse[3] = 120
DistributionPanel.DistributionPanel[0] = "Level-1"
DistributionPanel.DistributionPanel[1] = "Level-2"
DistributionPanel["Level-1"].Fuse[1] = 80
DistributionPanel["Level-1"].Fuse[2] = 80
DistributionPanel["Level-1"].Fuse[3] = 80
DistributionPanel["Level-1"].ChargingStation[0] = "NLCP013"
DistributionPanel["Level-1"].ChargingStation[1] = "NLCP014"
DistributionPanel["Level-1"].ChargingStation[2] = "NLCP015"
DistributionPanel["Level-1"].DistributionPanel[0] = "Level-1a"
DistributionPanel["Level-1a"].Fuse[1] = 32
DistributionPanel["Level-1a"].Fuse[2] = 32
DistributionPanel["Level-1a"].Fuse[3] = 32
DistributionPanel["Level-1a"].ChargingStation[0] = "NLCP130"
DistributionPanel["Level-1a"].ChargingStation[1] = "NLCP136"
DistributionPanel["Level-1a"].ChargingStation[2] = "NLCP132"
DistributionPanel["Level-2"].Fuse[1] = 80
DistributionPanel["Level-2"].Fuse[2] = 80
DistributionPanel["Level-2"].Fuse[3] = 80
DistributionPanel["Level-2"].ChargingStation[0] = "NLCP023"
DistributionPanel["Level-2"].ChargingStation[1] = "NLCP024"

Loosely speaking, the function of a typical load management system is to adjust the current consumed at each of the charging stations so that no Fuse is carrying over its rated current.

[chuck-h]

Some issues with the OCA model

1. How to represent single phase charging loads (either line-to-line on 3ph or line-to-neutral)
2. How to represent loads other than EV charge stations
3. How to represent current sensing points
4. How to distinguish between fuse rating and maximum managed load setting

[chuck-h]

Consider a data table representing "circuits". A circuit corresponds physically to a single current-carrying wire. Characteristics of a circuit include:

1. A circuit name
2. A source location (usually in an electrical panel)
3. A parent circuit
4. A continuous current rating

Installations may be single-phase or three-phase. Single-phase loads may be connected line-to-line or line-to-neutral. These arrangements are captured by treating each non-neutral conductor as a circuit.
Single-phase line-to-lline loads and three-phase loads are fed by two-pole and three-pole circuit breakers, respectively. A multipole circuit breaker "trips", and disconnects all poles, when any one circuit exceeds the breaker rating.

A second data table of loads will be useful. A load might be an EV charging station, or a non-EV load whose consumption is measured or estimated. A load will have connections to one, two, or three circuits; this can be represented in a load_connections table.

Questions
A circuit at any given time will be carrying a certain amount of current. This value might be reported by a charging station, measured by a separate sensor, or possibly estimated or computed. Should the circuit table be continually updated with current readings?