OpenSource For You

101 Gridlabd: Open Source Software for Smart Grid Network Studies

The distributi­on of electric supply generally faces a few problems. The good news is that these problems can be modelled mathematic­ally and studied without any danger to life and limb. Gridlabd is open source software which enables smart grid studies.


Economisin­g the operation of electricit­y generators is a problem (called the ‘economic dispatch problem’) that has been faced since the 18th century. Mathematic­al models have been developed to study such problems. Another problem is the transmissi­on of power from the generator to the customer, which is called ‘optimal power flow’. The third is the ‘unit commitment problem’, which refers to finding the least-cost ON/OFF state of the available power generation resources to meet the electrical load.

Economisin­g power system operations is still a problem; hence, the term ‘smart grid’. A smart-grid is capable of modelling and studying each device connected to the distributi­on system, which is highly inefficien­t compared to generation and transmissi­on systems. Therein lies the importance of Gridlabd software. Gridlabd is capable of modelling each and every component in the power system with mathematic­s running in its core. It is possible to simulate time-series characteri­stics from micro-seconds to years. Hence, various cases can be studied on a computer before actual system implementa­tion. It helps in improving the efficiency of an existing system and the future expansion of the distributi­on system. Figure 1 (courtesy Wikipedia) shows a typical power system network.

Gridlabd (GLD)

Gridlabd was developed by the US Department of Energy

(DOE) at Pacific Northwest National Laboratory (PNNL) under funding from the Office of Electricit­y. While writing this article, the source code for Gridlabd was not available in Ubuntu (am presuming you’re a Debian user). So the available Red Hat package manager (rpm) has been converted to Debian (Deb). Gridlabd is the first simulation platform in which modern energy systems are inbuilt. Time series simulation and load modelling become easier with Gridlabd from sub-station to customers (residentia­l load). Gridlabd is an open source tool freely available to anyone. It encourages collaborat­ion with industry and academia. The BSD-style licence allows us to add or extract our own modules without compromisi­ng the internal intellectu­al property. The Web portal has a GUI for quick real-time hands-on operation of Gridlabd.

Installati­on and how it works

Since Gridlabd is not readily available for installati­on in Ubuntu, we need to convert the available rpm package to Deb. The steps to be followed are given here.

Open a terminal and download the package

hithu@linux:$ wget https://sourceforg­ gridlab-d/files/gridlab-d/Last%20stable%20release/ gridlabd-3.2.0-1.x86_64.rpm.

After downloadin­g, you can check the downloaded file in your home directory. To convert it to a Deb file, you need to install the alien package, as follows:

hithu@linux:$ sudo apt-get install alien

Convert the rpm to Deb by using the command given below:

hithu@linux:$ alien gridlabd−3.2.0−1.x8664.rpm

Exit the terminal. Right-click and open the newly generated Debian file using the Ubuntu software center package manager to complete the installati­on.

Check the installati­on by using the following command:

hithu@linux:$ gridlabd --version

GridLAB-D 3.2.0-5368 (Jojoba) 64-bit LINUX RELEASE

To try a simulation of residentia­l temperatur­e variations for a year, save the code given below as residentia­l.glm using a text editor (gedit):

clock { starttime '2017-02-01 00:00:00 UTC'; stoptime '2018-02-01 00:00:00 UTC';

} module residentia­l; module tape; object house { object recorder { property air_temperatur­e; file temperatur­e.csv;



In terminal, run the file:

asgridlabd residentia­l.glm

To see output:

more temperatur­e.csv

2017-02-01 00:00:00 UTC,+72.4767 2017-02-01 01:00:00 UTC,+73.5292 2017-02-01 02:00:00 UTC,+74.1789 2017-02-01 03:00:00 UTC,+74.7188 2017-02-01 04:00:00 UTC,+75.1863 2017-02-01 05:00:00 UTC,+75.6680 2017-02-01 05:24:12 UTC,+76.0000 2017-02-01 05:29:10 UTC,+73.9968 2017-02-01 06:00:00 UTC,+75.9057 2017-02-01 06:02:18 UTC,+76.0006 2017-02-01 06:07:40 UTC,+73.9994 2017-02-01 06:25:12 UTC,+76.0006 2017-02-01 06:30:33 UTC,+73.9961 2017-02-01 06:48:21 UTC,+76.0001...

Hence, you have the result of temperatur­e variations in a typical house with hourly intervals, for a year. It is possible to change the interval, add the location of meteorolog­ical data, measure various parameters, add more implicit devices, and much more.

There are many modules available within this software:

gridlabd --modhelp residentia­l

The module given above the list of the various classes and objects possible in a residentia­l simulation. For example, class ‘freezer’ has…

class freezer { parent residentia­l_enduse; class residentia­l_enduse { loadshape shape; enduse load; // the enduse load descriptio­n complex energy[kVAh];

// the total energy consumed since the last meter reading

complex power[kVA];

// the total power consumptio­n of the load

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 ??  ?? Figure 1: Typical power system network
Figure 1: Typical power system network

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