Working Group Details
WGD3 - Bus Design in Air Insulated Substations
|Working Group Chair||
|IEEE Program Manager|
This design guide provides direction for the substation engineer in the design of air insulated substations. This guide provides users with information on typical bus arrangements including various criteria necessary to develop bus arrangement decisions. The guide is applicable to both rigid bus and strain bus designs for outdoor and indoor, air-insulated, alternating current substations. This guide includes a method to calculate ampacity for electrical bus and ampacity tables for typical bus types and sizes. This guide also provides design criteria and a method to calculate electromechanical forces on insulators and bus resulting from gravity, wind, ice, short circuit forces, and thermal expansion. This guide does not consider the following: a) The electrical criteria for the selection of insulators (see IEEE Std 1313.2TM[B22]) b) The seismic forces to which the substation may be subjected (see IEEE Std 693TM and IEEE Std 1527TM) c) The design of bus mounting structures (see ASCE Manual and Report on Engineering Practice No. 113) d) Design considerations for contaminated environments (see IEEE Std 1313.2-1999 [B22]) e) Installation methods f) Design of direct current buses
Rigid-bus structures for outdoor and indoor, air insulated, and alternating current substations are covered. Portions of this guide are also applicable to strain bus structures or direct current substations, or both. Ampacity, radio influence, vibration, and forces due to gravity, wind, fault cur-rent, and thermal expansion are considered. Design criteria for conductor and insulator strength calculations are included.
A proper design of the substation bus ensures a safe and reliable operation of the substation and the power system. Two different types of buses are used in substations, the rigid bus and the strain (cable). This guide provides information on the different bus arrangements used in substations stating the advantages and disadvantages of each. Also it provides information as related to each bus type and construction. Once the bus type is selected, this guide provides the calculation tools for each bus type. Based on these calculations, the engineer can specify the bus size, forces acting on the bus structure, number of mounting structures required, and hardware requirements.