# 6-Bus System (System II)

I. Introduction:

$$\bullet$$ The network of this test case is shown in the figure given below, where the near-end $$3\phi$$ fault is considered. The generating units are connected to all busbars except Bus 2 and 5, while the loads are not shown in the diagram.
$$\bullet$$ This system has same number of directional overcurrent relays (DOCRs) as compared with the first 8-bus test case. This is because the two additional buses are connected to the generating units and then feed the network through two transformers without using DOCRs on that two buses. It is supposed that the generators and transformers will be protected by their own protection systems.
$$\bullet$$ In [1], the relays operating time is modeled by using Sachdev formula instead of the standard formula by IEC and ANSI/IEEE that is considered in [2, 3]. Also, ($$TMS^{max}=11$$) is considered in [1] instead of ($$TMS^{max}=1.1$$) as in [2, 3].
$$\bullet$$ The CT ratios ($$CTRs$$), the $$3\phi$$ short-circuit current for each P/B pair of relays, the side constraints of each variable, and the coordination time interval ($$CTI$$) are given below (click on them for bigger size):

II. Single-Line Diagram:

$$\bullet$$ This single-line diagram was drawn by Ali R. Alroomi in Sept. 2015 and all the necessary data were coded in MATLAB m-files.

III. Files:

$$\bullet$$ High Resolution Images (JPEG and TIFF Formats) [Download]
$$\bullet$$ Results Tester (MATLAB, m-file Format) [Download]

IV. References (Some selected papers that use this system):

[1] M. M. Mansour, S. Mekhamer, and N.-S. El-Kharbawe, "A Modified Particle Swarm Optimizer for the Coordination of Directional Overcurrent Relays," IEEE Transactions on Power Delivery, vol. 22, no. 3, pp. 1400–1410, Jul. 2007.
[2] D. Vijayakumar, and R.K. Nema, "Superiority of PSO Relay Coordination Algorithm over Non-Linear Programming: A Comparison, Review and Verification," in Joint International Conference on Power System Technology and IEEE Power India Conference, 2008 (POWERCON 2008), pp. 1-6, Oct. 2008.
[3] D.K. Singh, and S. Gupta, "Optimal Coordination of Directional Overcurrent Relays: A Genetic Algorithm Approach," in 2012 IEEE Students' Conference on Electrical, Electronics and Computer Science (SCEECS), pp. 1-4, Mar. 2012.
[4] M. El-Mesallamy, W. El-Khattam, A. Hassan, and H. Talaat, "Coordination of Directional Overcurrent Relays Using Artificial Bee Colony," in 22nd International Conference and Exhibition on Electricity Distribution (CIRED 2013), pp. 1-4, Jun. 2013.
[5] S. Ralhan, and S. Ray, "Directional Overcurrent Relays Coordination Using Linear Programming Intervals: A Comparative Analysis," in 2013 Annual IEEE India Conference (INDICON), pp. 1-6, Dec. 2013.