A load flow study is a study that helps to determine proper loading as well as whether the proper voltage is maintained at each circuit due to voltage drop. In simpler terms, it helps to determine how much current load you have and whether the equipment is overloaded or not. With the voltage, you need to keep the values within the nominal range. This study helps to determine if you are within the recommended tolerances within these limits.
To start a load flow study, you need to get the loading data for your plant. Motor and horsepower loading are the primary items that are required. You will need the information of KW or KVAR loading for dynamic loads. For static loads, you will need the KW or resistive load demand. You will need the demand and diversity (how often it runs) as well for the system. With all this information you are comparing all of this versus the ratings of the equipment. Most of this information can be taken from the nameplate on the piece of equipment such as the bus rating of the gear.
A one-line is not critical for the Load Flow Study, but it will help you get started with the study. If you do not have one, a study can still be done, and in fact, by using the digital tools to do the load flow study you will generate a simple one line.
Once the Load Flow Study has been done, you can expect to receive a report. This report can include any overload issues such as an overloaded piece of equipment. The report will also include any concerns with the system.
A typical Load Flow study usually needs to be done every 3-5 years or as the loads change or the demand increases. The plant engineer or maintenance supervisor is usually the one responsible for requesting the load flow study be done.
Once abnormalities are identified, components can be replaced as needed, or whole new pieces of gear can be brought in to help mitigate the issues.
A load flow study is important to help ensure that your transformers, breakers, cables, etc. do not become overloaded. Once a device is overloaded, the excess temperature is generated which can cause issues with the longevity of devices as well as potential fire risks. Voltage drops being kept to a minimum can also help to make sure that your equipment performs the way it was intended.