Written by Harvey Ursaki, November 19, 2019
Power transformers are used throughout the Electrical Industry networks to step up voltage for transmission or step-down voltage for distribution.
A power utility transformer is one of the more complicated machinery in the electrical industry. The design of the transformer is in two stages as follows:
Internal design – this is the responsibility of the transformer manufacturer. Following a client’s specifications, the manufacturer builds the transformer accordingly.
Installation design – this is the responsibility of the client once the transformer is manufactured and delivered, unless the transformer manufacturer is contracted to do both.
The design of the transformer is also regulated by accepted international standards such as IEEE and NEMA, and within individual countries, each having their own codes and standards with regards to transformer manufacturing as well.
By using these standards, and with the advancement of the web-based programming it is now possible to automate the installation design of the transformers!
Electrical Design Management’s (EDM) HV Transformer Calculator module is a powerful tool for engineers or designers responsible for the installation design as well as the protection and control design of high voltage power transformers.
From sizing the transformer, selecting CT quantities and ratios, to choosing transformer alarms and relaying, the calculator organizes and displays your design on the fly.
By taking you step by step in determining your design parameters of the Power Transformer, the final design, from transformer sizing, protection and control to cabling, is completed by module.
The module then produces the following drawings: Single Line Diagrams, Alarm and Tripping Schematics as well as Wiring Diagrams, all with the click of a few buttons.
Let’s look at a typical trip and alarm feature of the module.
Below is a sample of the drawings that can be produced by simply selecting the desired alarm or trip boxes! This example is using auxiliary relays as an selectable option to control the alarm functions, EDM allows you to select other options like micro-process relay as a control function.
Also, you can add any alarms or trips you require to the list, these will also be included in the schematic drawings!
The drawings are produced in DFX format and can be saved and imported to most CAD programs for additional detailing to complete the drawings.
Yes, Power Transformer Installation Design canand should be automated with EDM software leading the way!
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