Network Module

The Net module provides comprehensive functionality for creating and manipulating power system network models in Julia. It includes features for defining buses, branches, transformers, prosumers, and shunts, as well as methods for running power flow analysis and managing network modifications.

Creating a Network

Start by creating a new network object:

using Sparlectra

# Create a new network with a name and base MVA
net = Net(name = "example_network", baseMVA = 100.0)

Adding Components

Buses

# Add buses with different types (PQ, PV, Slack)
addBus!(net = net, busName = "B1", busType = "PQ", vn_kV = 110.0, vm_pu = 1.0, va_deg = 0.0)
addBus!(net = net, busName = "B2", busType = "PQ", vn_kV = 110.0, vm_pu = 1.0, va_deg = 0.0)
addBus!(net = net, busName = "B3", busType = "PQ", vn_kV = 110.0, vm_pu = 1.0, va_deg = 0.0)
addBus!(net = net, busName = "B4", busType = "PQ", vn_kV = 110.0, vm_pu = 1.0, va_deg = 0.0)
addBus!(net = net, busName = "B5", busType = "Slack", vn_kV = 110.0, vm_pu = 1.0, va_deg = 0.0)

AC Lines

# Add AC lines with physical parameters
addACLine!(net = net, fromBus = "B1", toBus = "B2", length = 25.0, r = 0.2, x = 0.39)
addACLine!(net = net, fromBus = "B1", toBus = "B3", length = 25.0, r = 0.2, x = 0.39)

# Add AC lines using the PI model (directly with per-unit values)
addPIModelACLine!(net = net, fromBus = "B3", toBus = "B4", r_pu = 0.05, x_pu = 0.2, b_pu = 0.01, status = 1)

Transformers

# Add a two-winding transformer
add2WTrafo!(
    net = net, 
    fromBus = "B2", 
    toBus = "B4", 
    sn_mva = 100.0, 
    vk_percent = 10.0, 
    vkr_percent = 0.5, 
    pfe_kw = 20.0, 
    i0_percent = 0.1
)

# Add a transformer using the PI model
addPIModelTrafo!(
    net = net, 
    fromBus = "B4", 
    toBus = "B5", 
    r_pu = 0.01, 
    x_pu = 0.1, 
    b_pu = 0.0, 
    status = 1, 
    ratio = 1.05
)

Prosumers (Generators and Loads)

# Add loads
addProsumer!(net = net, busName = "B1", type = "ENERGYCONSUMER", p = 1.0, q = 2.0)
addProsumer!(net = net, busName = "B2", type = "ENERGYCONSUMER", p = 1.0, q = 2.0)

# Add a slack generator
addProsumer!(
    net = net, 
    busName = "B5", 
    type = "SYNCHRONMASCHINE", 
    referencePri = "B5", 
    vm_pu = 1.0, 
    va_deg = 0.0
)

# Add a PV generator
addProsumer!(
    net = net, 
    busName = "B1", 
    type = "GENERATOR", 
    p = 1.1, 
    q = 2.0, 
    vm_pu = 1.02
)

Shunts

# Add a shunt to a bus
addShunt!(net = net, busName = "B1", pShunt = 0.0, qShunt = 1.0)

Running Power Flow

# Set parameters
tol = 1e-6
maxIte = 10  

# Run power flow
etime = @elapsed begin
  ite, erg = runpf!(net, maxIte, tol, 0)
end

# Check results and calculate losses
if erg != 0
  @warn "Power flow did not converge"        
else
  calcNetLosses!(net)
  printACPFlowResults(net, etime, ite, tol)
end

Modifying the Network

Updating Component Parameters

# Update a branch's parameters
brVec = getNetBranchNumberVec(net = net, fromBus = "B1", toBus = "B2")
updateBranchParameters!(
    net = net, 
    branchNr = brVec[1], 
    branch = BranchModel(
        r_pu = 0.02, 
        x_pu = 0.2, 
        b_pu = 0.01, 
        g_pu = 0.0, 
        ratio = 1.0, 
        angle = 0.0, 
        sn_MVA = 100.0
    )
)

# Update bus powers
addBusLoadPower!(net = net, busName = "B1", p = 2.0, q = 1.0)
addBusGenPower!(net = net, busName = "B5", p = 3.0, q = 1.5)
addBusShuntPower!(net = net, busName = "B2", p = 0.0, q = 1.0)

Setting Branch Status

# Change a branch's status (in-service or out-of-service)
setNetBranchStatus!(net = net, branchNr = brVec[1], status = 0)  # 0 = out of service

Removing Components

See the Component Removal documentation for details on removing components from networks.

Handling Isolated Buses

# Mark isolated buses in the network
markIsolatedBuses!(net = net, log = true)

# Clear (remove) isolated buses
clearIsolatedBuses!(net = net)

Validating the Network

Always validate your network after making significant modifications:

result, msg = validate!(net = net)
if !result
  @error "Network is invalid: $msg"
end

API Reference

Sparlectra.add2WTrafo! — Method

Add a two-winding transformer to the network.

Arguments

net::Net: The network to which the transformer will be added.
fromBus::String: The name of the bus where the transformer originates.
toBus::String: The name of the bus where the transformer terminates.
sn_mva::Float64: Rated power of the transformer.
vk_percent::Float64: Voltage regulation percent of the transformer.
vkr_percent::Float64: Voltage regulation percent of the transformer.
pfe_kw::Float64: Iron loss of the transformer.
i0_percent::Float64: No-load current percent of the transformer.
status::Int: The status of the transformer. Default is 1.