The construction of new substations and the expansion of existing facilities are commonplace projects in electric utilities. However, due to the complexity, very few utility employees are familiar with the complete process that allows these projects to be successfully completed. This article series will attempt to highlight the major issues associated with these capital intensive construction projects, and provide a basic understanding of the types of issues that must be addressed during this process.
Types of Substation:
There are four major types of electric substations. The first type is the switchyard at a generating station. These facilities connect the generators to the utility grid and also provide off-site power to the plant. Generator switchyards tend to be large installations that are typically engineered and constructed by the power plant designers and are subject to planning, finance, and construction efforts different from those of routine substation projects. Because of their special nature, the creation of power plant switchyards will not be discussed here, but the expansion and modification of these facilities generally follow the routine processes.
Another type of substation is typically known as the customer substation. This type of substation functions as the main source of electric power supply for one particular business customer. The technical requirements and the business case for this type of facility depend highly on the customer’s requirements, more so than on utility needs, so this type of station will also not be the primary focus of this discussion.
The third type of substation involves the transfer of bulk power across the network and is referred to as a switching station. These large stations typically serve as the
The fourth type of substation is the distribution substation. These are the most common facilities in electric power systems and provide the distribution circuits that directly supply most electric customers. They are typically located close to the load centers, meaning that they are usually located in or near the neighborhoods that they supply, and are the stations most likely to be encountered by the customers. Since the construction of distribution stations creates the majority of projects in utility substation construction budgets, these facilities will be the other major focus of this series article.
Source: Electric Power Substations Engineering