Power Cases

In following cases, a method of equivalencing is used. We need equivalencing to reduce simulation time. It is useful especially when we want to study a large system with hundreds of thousand components by reducing the size of the power grid to a model system with fewer components than the original one. However, one disadvantage of an equivalent is that the reduced system can`t be used to study another behavior that the one for which reduction has been done. But if we focus of specific behaviors of the original, the equivalent can generate those behaviors similar enough and save a lot of time. Therefore, engineering insight is required between the size of the equivalent and the accuracy of the simulation results.

The first equivalencing method was developed by Ward in 1949 and it is still widely used. Another classic method is called a REI (radial, equivalent and independent) method. PowerWorld uses one of the Ward type methods. Moreover, there are basically two types of equivalencing, static equivalencing and dynamic equivalencing. Static network reduction is usually used for system planning and development as well as for system on-line monitoring and control purposes. Dynamic equivalencing methods are usually employed to create equivalent synchronous machines in order to mimic the transient stability behaviors of the original system. Also, it can be used to model equivalent loads. [1]

[1] By Wonhyeok Jang’s comments

Requirements that IEEE cases should meet:

1. Use PowerWorld version 17
2. Save cases as raw files.
3. The cases will be saved in different formats:

  • Pwb, pwd for PowerWorld (version 17)
  • PSSE (version 33)
  • PSLF

Power Cases

Case 1 – IEEE 9 Bus Systems

This IEEE 9 Bus Test Case represents a portion of the Western System Coordinating Council (WSCC) 3-Machines 9-Bus system. The system contains 3 generators, 9 buses and 3 loads. Read more …

Case 2 – IEEE 14 Bus Systems

The IEEE 14 Bus Test Case represents a portion of the American Electric Power System which is located in the Midwestern US as of February, 1962. This 14 bus system has 14 buses, 5 generators and 11 loads. Read more …

Case 3 – IEEE 30 Bus Systems

The IEEE 30 Bus Test Case represents a portion of the American Electric Power System (in the Midwestern US) as of December, 1961. This bus system contains 15 buses, 2 generators and 3 synchronous condensers. Read more …

Case 4 – IEEE 39 Bus Systems

This IEEE 39 bus system is well known as 10-machine New-England Power System. This bus system has 10 generators and many transforms between bus and bus, summing up to 46 lines and transforms. Read more …

Case 5 – IEEE 57 Bus Systems

The IEEE 57 Bus Test Case represents a portion of the American Electric Power System (in the Midwestern US) as it was in the early 1960′s. This system has 57 buses, 7 generators and 42 loads. Read more …

Case 6 – IEEE 118 Bus Systems

This IEEE 118 Bus Test Case represents a portion of the American Electric Power System (in the Midwestern US) as of December, 1962. This IEEE 118 bus system contains 19 generators, 35 synchronous condensers, 177 lines, 9 transformers and 91 loads. Read more …

Case 7 – IEEE 300 Bus Systems

This IEEE 300 Bus Test Case was developed by the IEEE Test Systems Task Force under the direction of Mike Adibi  in 1993. This IEEE 300 bus system contains 69 generators, 60 LTCs, 304 transmission lines and 195 loads. Read more …