  In Energy Management System (EMS) applications and many other off-line
planning and study tools, one-line diagram (OLND) of the whole system and
stations is a straightforward view for planners and operators to design,
monitor, analyze, and control the power system. Large-scale power system OLND
is usually manually developed and maintained. The work is tedious,
time-consuming and ease to make mistake. Meanwhile, the manually created
diagrams are hard to be shared among the on-line and off-line systems. To save
the time and efforts to draw and maintain OLNDs, and provide the capability to
share the OLNDs, a tool to automatically develop substation based upon Common
Information Model (CIM) standard is needed. Currently, there is no standard
rule to draw the substation OLND. Besides, the substation layouts can be
altered from the typical formats in textbooks based on factors of economy,
efficiency, engineering practice, etc. This paper presents a tool on substation
OLND automatic generation and visualization. This tool takes the substation
CIM/E model as input, then automatically computes the coordinates of all
components and generates the substation OLND based on its components attributes
and connectivity relations. Evaluation of the proposed approach is presented
using a real provincial power system. Over 95\% of substation OLNDs are
decently presented and the rest are corner cases, needing extra effort to do
specific reconfiguration.
