User guide¶

The simplest use can be understood with an example. Suppose we want to calculate the power flow of the following system:

The following steps should be considered:

Import modules
Define or load grid parameters
Generate a grid instance
Read grid parameters
Run power flow
Post process results
Plot results

Import modules¶

First of all, we have to import the relevant modules and classes:

import numpy as np

from pydgrid import grid

Define or write grid parameters¶

The network can be introduced in two ways:

Python dictionary
json file with the same structure as in the case of the previous python dictionary

For the proposed system example the following elemnts from pydgrid should be considered:

data = {
        "buses":[
                 {"bus": "B1",  "pos_x":   0, "pos_y":   0, "units": "m", "U_kV":20.0},
                 {"bus": "B2",  "pos_x":  10, "pos_y":   0, "units": "m", "U_kV":0.4},
                 {"bus": "B3",  "pos_x": 100, "pos_y":  0, "units": "m", "U_kV":0.4}
                ],
        "grid_formers":[
                        {"bus": "B1",
                        "bus_nodes": [1, 2, 3], "deg": [0, -120, -240],
                        "kV": [11.547, 11.547, 11.547]}
                       ],
        "transformers":[
                        {"bus_j": "B1",  "bus_k": "B2",  "S_n_kVA": 1000.0, "U_j_kV":20, "U_k_kV":0.42,
                         "R_cc_pu": 0.01, "X_cc_pu":0.04, "connection": "Dyn11",   "conductors_j": 3, "conductors_k": 4},
                       ],
        "lines":[
                 {"bus_j": "B2",  "bus_k": "B3",  "code": "lv_cu_150", "m": 100.0},
                ],
        "loads":[
                 {"bus": "B3" , "kVA": 300.0, "pf": 0.85,"type":"3P+N"}
                ],
        "shunts":[
                 {"bus": "B2" , "R": 0.001, "X": 0.0, "bus_nodes": [4,0]}
                 ],
        "line_codes":
            {"lv_cu_150":  {"Rph":0.167,"Xph":0.08, "Rn":0.167, "Xn": 0.08}
            }
       }

Generate a grid instance¶

grid_1 = grid()

Read grid parameters¶

grid_1.read(data)

Execute power flow¶

grid_1.pf()

Plot results¶

In the case of using jupyter notebook results can be visualized with a bokeh plot that includes hover tools.

from pydgrid.plot_bokeh import plot_results
plot_results(grid_1)

example1

An on-line working jupyter notebook with the same example can be obtained here: