Over the last few decades, the Progress Energy Carolinas (PEC) service territory has been one of the fastest-growing areas in the United States. To meet this demand, PEC needs to plan, design, construct and retrofit power transmission substations. Reliable operation of a substation requires accurate relay logic design and installation. This in turn underscores the need to produce accurate and detailed protection and control (P&C) construction drawings to mitigate any error precursors and misinterpretations. To achieve these deliverables, a robust engineering process and versatile design tools are imperative.

In addition to PEC's growing demand for power substations, there are industrywide initiatives such as smart grid and distribution supervisory control and data acquisition (D-SCADA) that have increased the P&C engineering workload exponentially. When employing traditional engineering design processes with limited resources, it is not practical to deal with this workload effectively. As a result, PEC's transmission operations and planning department has designed, developed and implemented the Relay Automation Program for Intelligent Drawings (RAPID) process to standardize and automate the P&C engineering design process. The objective of this effort was to eliminate latent design errors, shorten project lead times, enhance quality and elevate the production rate.

Previous Process

To complete the P&C engineering design phase, PEC uses a wide variety of processes. Two design processes have been identified for improvement: three-tiered data entry tasks for project drawing information and multiple data duplication of relay logic data.

The title blocks of project drawings require specific information, including project name, drawing type, drawing title, revision information, drawing number for organized record keeping and drawing identification. This information is entered in a drawing transmittal form (DTF), which lists all the drawings required for a given P&C design project. DTF enables construction personnel to quickly retrieve the appropriate drawing for a relay panel, major equipment installations, wiring and functional testing.

To facilitate this need, the project drawing information entered in DTF also needs to be entered in each computer-aided design (CAD) drawing title block. To perform this task, each drawing used in a project requires the project drawing information to be entered manually, one at a time. This involves significant time and effort. The project CAD drawings are stored in a document management system (DMS) for centralized accessibility, future reference, asset maintenance and potential expansions.

For organized storage and future retrieval of CAD drawings, the project information needs to be entered a third time into the DMS for the corresponding project. Because of this requirement, the user must manually enter the project drawing information as DMS attributes for each drawing.

On the whole, during the life cycle of the project design, any changes to the project information requires the user to manually update the DTF, CAD drawings and DMS attributes, leading to labor-intensive and duplicative processes. With this process in place, there was an urgent need for process improvement to achieve efficiency gains.

Relay logic data is required for reliable and safe substation operation. The criteria for relay logic design are based on the substation configuration, protection scheme, voltage class, existing schemes and application methodology. To control and monitor functional components of a substation, several standard relay panel types have been established, including line, bank, bus, capacitor and tie-breaker panels. A relay panel contains a combination of Schweitzer Engineering Laboratories (SEL) relays and additional hardware. PEC uses SEL-300 and SEL-400 series relays extensively in its transmission P&C engineering design processes.

Several individual relays are used to create the P&C functional (logic) drawing. Each relay used in the functional drawing has its own settings sheet and dc elementary drawing. The relay logic data is primarily designed in the settings sheet. Subsequently, the former data is entered in functional and dc elementary drawings. For instance, a line panel functional drawing consists of the SEL-311C backup relay, SEL-321 primary relay and SEL-351S breaker relay. The user manually enters relay I/O data in individual relay settings files, functional drawings and dc elementary drawings. Also, the line number, breaker number, voltage class, bus number, bank number and so forth must be entered several times. The result is a redundant, highly error-prone and cumbersome process.

A Friendly Solution

To meet the previous process challenges, PEC developed and implemented the RAPID process to streamline P&C engineering design processes. Custom-built toolbars were designed within the CAD application for quick accessibility to various design elements and design tools to produce project-specific P&C drawings. The RAPID process is bifurcated into RAPID I and RAPID II, each providing the solutions to the unique challenges imposed by the conventional processes outlined previously.

To enhance the transmission P&C engineering design process, the RAPID tool provides many features:

• Interface to enforce standardization
• Graphic access to relay drawing templates
• Intuitive relay engineering design process
• Expedited changes during the design phase
• Data sync to CAD drawings
• Single-tiered data entry
• User-friendly design tools.

RAPID I

RAPID I was devised to eliminate the existing three-tiered data entry of project drawing information in the P&C engineering design process. The premise is to enter the project drawing information in DTF, which should automatically synchronize the corresponding CAD drawings title block information and DMS attributes. To design this automated solution, intelligence was applied to the DTF, drawing title blocks and DMS attributes.

Project drawing information changes made in the DTF are now automatically synchronized to the drawing title block, which in turn synchronizes the DMS attributes. This improvement eliminates three-tiered data entry and embraces single-tiered data entry.