How do engineering design tools fit in with AM/FM/GIS?

How do engineering design tools fit in with AM/FM/GIS?

Ed Hedges
Kansas City Power & Light Company
4400 East Front Street
Kansas City, MO 64120-1039

Kelley D. Grant, P.E.
Intergraph Corporation
MS: LR23A1
Huntsville, AL 35894

Changes in business rules have driven the need for design tools in AM/FM/GIS
AM/FM/GIS applications have been greatly impacted by technological changes that have propelled more and more facets of the utility business process into automation. As systems have become more open, utilities have found more opportunities for integration and new ways to take the greatest advantage of their data. This commonly involves bringing more users into the automated world.

This paper discusses distribution designers, users who often spend as much time in the field as in the office. They work with customers, customer representatives, mapping, property accounting, field crews, and standards engineers. Distribution designers have a variety of backgrounds; typically, they are not engineers, but come from the mapping or drafting departments and are trained in design. These designers contribute greatly to the maintenance of the AM/FM/GIS data by creating their designs directly in the system. They also benefit from the existing data when planning and designing new jobs or reworking older circuit sections.

One of the key tools needed by these designers is the ability to do some amount of electrical and structural design analysis within their AM/FM/GIS jobs. Though many of their jobs follow company standards, these tools allow them to examine special circumstances to be sure their designs fall within the desired limits. The next issue is to determine what tools are needed by the designers. Available packages range from very simple to highly complex, and the trick is to meet the designers' needs, but not slow them down with too many details.

What are the design tool requirements?

What is the business process?

We will first examine the business process that KCPL is implementing. Their designers often work directly with the customer, visiting the site and creating the designs. They draw the designs directly in the AM/FM/GIS application, using the existing electrical and landbase data, then review them with the customer and make changes as needed. Once the design is approved, it is ready to be scheduled. The design now goes to the crews to be constructed and then to the mapping department for as-built updates and any necessary update processes.

Our reason for describing the business process is to define the role of the designers. They are expected to provide a quick turnaround of jobs, provide instructions to the crews, and generate accurate materials lists. To accomplish these tasks, they concentrate on creating the initial design and reviewing it once to make as-built updates. The designers must populate only the attributes and relationships required for initial design. The mappers complete the as-built changes and assure relationships and data for on-going operations prior to posting.

Users Skills and Roles

A designer's specific role will help determine the complexity of the tools that are needed. A designer who is deeply involved in custom design jobs may be interested in more complex tools, while a designer who relies more on standards and common jobs may prefer simple tools. The background, role, and focus of the designers at a utility will play a large part in what tools are most appropriate. For KCPL, the designers will work in the AM/FM/GIS environment, but will be doing repetitive, routine jobs and will not be ultimately responsible for clean, postable data. They will be interested in digitizing their jobs so that they can perform some level of analysis, generate a construction plot, and pass their CU information to work management. This will allow them to be most concerned with the graphic display and establish only a minimum of the relationships and attribution.

What are the common job types?

The designers' jobs differ greatly from one district to another. Some districts in more established areas tend to have jobs geared more toward maintaining and re-working older or smaller capacity lines. The newer or growing areas include some of that type of work, but they also have work that is entirely new. Designers of new work encounter a fairly standard set of facilities, so the work will look similar and be more easily standardized.

The highest volume of KCPL's jobs are for new customers-usually subdivisions or commercial developments. In these cases, the loads are projected, based on typical data. The next-largest volume of KCPL's jobs are maintenance upgrades. These jobs require more analysis of the current data and are a great way to take advantage of the existing AM/FM/GIS data. The lowest-volume jobs are custom and/or industrial. These are the jobs that require complex analysis and must have real projected loads so that the designers can create accurate designs.

What is driving the exactness of the results?

In our discussions, we found a combination of available approaches for these tools. Traditionally, many of the calculations were reduced to a table in the book of company standards. Some tools used fairly standard calculations, while others followed more of a rule-of-thumb method. Then, of course, some tools used set calculations with various constants, look-up table variables, and safety factors. These were more complex and required more expertise in setting up and in understanding the result. We found that all of these approaches were useful in certain situations; however, we were most interested in minimizing design time and in using the tool as a "sanity check" for a veteran designer or as a learning tool for a new designer.

Additional influences drove our focus. We wanted to forego the detailed analysis used by standards to establish standard materials. The designer tools have to evaluate only the current standard materials, not all available industry materials. Another option we discussed was using look-up tables. However, we found that lower-cost design requires more analysis at the specific job level and cannot be accomplished with traditional broad-based table look-up. We also wanted the designers to have all the tools available to them in the AM/FM/GIS design environment.

Another issue was data collection. For complex tools, this could be too timeconsuming and costly for common high-volume designs. Also, how and where would this data be stored? The AM/FM/GIS data models are not geared for this level of data. It may be found in homegrown databases, but is often not available and must be collected. In this case, more inputs or standards-based defaults are required, adding work for the designer. Resorting to defaulting values loses some of the benefit of the more complex computation. Even when this data is gathered, the issue of determining the best storage location remains. If storage is not in the GIS data, certain considerations regarding the linking of this data must be made. Facilities may need to be treated in different ways, depending on what is tracked as assets and what lifecycle they go through in GIS or Work Management applications.

One significant issue required that we look closely at the more rigorous approach to the calculations. KCPL is currently conducting a pole inventory and checking the attachments and moments of all their poles. They are finding situations in which many foreign attachments are being placed on the poles. More and more disputes have arisen recently about who is responsible for replacing these poles. Because of the recent attention of the pole moment, KCPL wants to be sure they are basing their calculations on clear industry standards.

Is IT best to integrate, interface or write custom tools?

First, the general answer

We discussed with other utilities how they have addressed design tools in their AM/FM/GIS environments. We learned that utilities are using the full range of options, from complex high-end packages, to mid-range packages, to custom in-house tools, to integrated table look-ups.

The main complaint on the high-end package is the cost. To provide this solution to many users can be cost prohibitive. When this is the case, it is difficult to justify adding the cost of integrating or interfacing the design package to the AM/FM/GIS application. Often this solution is used on one or two seats to address the small percentage of large or complex jobs and to establish company standards.

The mid-range packages are attractive. This is a cost-effective option for a large number of users and lends itself to interfacing or integrating. These packages tend to require fewer inputs, use generalized calculations, and provide approximate results. However, not many of these packages have been integrated or interfaced to AM/FM/GIS applications, so there aren't many running examples. This range of package also seems to be used independently, but on more seats than the higher-priced package.

We also discussed with these utilities the advantages and disadvantages of custom-written tools-tools written specifically for the utility and maintained in house. This options allows the users to specify exactly what they want, and the tools can be integrated directly into the AM/FM/GIS environment. It also requires that in-house developers or subcontractors who know the AM/FM/GIS application and model write and maintain these tools. Such personnel can be hard to find and especially hard to keep. A major drawback of this approach is that when the platform moves forward, these tools require upgrade and maintenance work. This option may also prove to be cost prohibitive.

The last option we discussed was integrated, hard-copy look-up tables. We discussed making standard look-up tables available to the designers, but we decided that automating existing look-up charts would not provide significant process improvements. The automated solutions would be more tailored for the situation and be more beneficial to the designers.

Now, for the specific KCPL answer

In our workshop, we determined who our focus users are, how many we must consider, and at what complexity level they work. First, our users are the designers. There are approximately 30 of these users, so cost was a factor. The designers have the expertise to operate in an AM/FM/GIS environment and can benefit from the existing data, STORMS interface, and user environment. KCPL has seen the difficulty involved with finding and keeping skilled AM/FM/GIS developers, so we elected to look for a COTS package that would be easy to maintain.

Since all of these issues were addressed in our workshop discussions, we decided to go with a mid-range package that would meet the needs of the planners for the majority of their jobs. The tools we chose were a Circuit Load Calculator, Secondary Optimization for conductor and transformer sizing, Streetlight Design for conductor sizing, Pole Moment, and Guying. These tools will be integrated into the planners' user environments and will be easy to use and understand. Designers will gain from automatic updates that apply the results to their design, based on the calculations they run.

With the many design tools available, there is sure to be one to meet the needs of any individual user. Determining those needs is half the battle, and we hope this examination of our own process will help others make such a determination. We have completed the design of this package and are working through the build phase. We are eager to get the tools into the hands of the users and reap the benefits they will yield.