DRY “Don’t Repeat Yourself”

Modeling Steel for Electrical Substations

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Utilizing Autodesk Inventor for modeling steel structures benefits our electric utility clients in several ways. We can minimize the time spent reworking or repeating structural designs. By applying Inventor’s modeling geometry for the design and detailing, we save time and minimize potential errors or design flaws. These aspects benefit our clients by reducing billable time and minimizing potential errors.

1.      Steel analysis and detailing

2.      Validation of electrical clearances

3.      Station drawings

When designing elements of an electrical substation, steel structures play a major role in the integrity and reliability of the substation’s operation. Therefore, 3D modeling provides a streamlined process for steel analysis/design, steel detailing, and creating the substation plans and elevations.

While the analysis is performed, the detail drawings begin. If a part changes, the model is revised and drawings will update to reflect the revised part. Once the steel drawings are completed, we utilize the steel model to create station drawings. These include the overall plans, elevations, and necessary details.

Here are two examples of how this process works and why it benefits our clients. Example 1 demonstrates the addition of equipment to an existing steel structure. Example 2 demonstrates the design of a new steel structure.

Example 1: Load Analysis of an Existing Structure

The client needed to add new current and potential voltage transformers to an existing equipment support truss. We needed to validate the capacity of the existing truss for the new equipment. The team created a model of the existing truss using Inventor. The model’s geometry was then utilized by Robot Structural Analysis (RSA) to check that the existing truss would be able to support the new equipment. The analysis showed that the existing truss did not have adequate capacity to support the new equipment and switches. Using the existing truss model, we engineered a new structure which would support the added equipment. The new structure needed to be built above and through the existing truss. Once the analysis was completed, we created the steel detailing drawings from the Inventor model, not repeating ourselves. 

Example 2: New Steel Structure Design

A new structure was created using fabricated welded steel sections, eight or twelve-sided. Before beginning the actual design, we created a parameterized assembly to properly place the new equipment to validate required electrical clearances. There was some setup time involved, but the flexibility allowed us to resize the structure as needed to gain the required clearances. Once the dimensions were verified, we began detailing and design in parallel. We laid out the detail sheets using the Inventor model and analyzed the overall structure using RSA. The engineers checked all the bolted and welded connections using finite element analysis (FEA) from the Inventor model’s geometry. By utilizing the same geometry for the design and detailing, our team saved time and did not repeat ourselves.   

Conclusion

Modeling steel structures for electrical substations increases both efficiency and accuracy. As an engineering consultant, we have increased confidence these designs will work for our clients. Our clients have peace of mind that we have made the best use of technology to benefit their projects!