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1 Read the system input data required for load flow.

2 Run the load flow program for the distribution network and compute the power loss and voltages at various nodes.

3 Calculate the differences in voltages ΔVtie(x) between the two buses across which different tie switches are placed to be connected; x = 1, 2, 3, … Stie, where Stie = number of tie switches.

4 Form a table for the above calculated voltage differences for all of the tie switches.

5 From the above table, select the tie switch for which the value of ΔVtie(x) is maximum. Suppose it is the tie switch ‘n’ such that (ΔVtie,max = ΔVtie(n)).

6 Compare the value of the (ΔVtie,max) with a set threshold value (θ). If ΔVtie,max is greater than the threshold value, go to the next step, else stop.

7 Compare the node voltages of the two nodes across which the tie switch ‘n’ is connected. Select the node with the smallest value. Let it be the node ‘m’ with node voltage Vm.

8 Close the tie switch ‘n’ and simultaneously open the sectionalizing switch connected to node ‘m’.

9 Run the load flow for the above reconfigured distribution network and compute the power loss. Let it be Ploss.

10 In the next step, close the previously opened sectionalizing switch and open its adjacent sectionalizing switch within the same loop.

11 Run the load flow for the above reconfigured distribution network and compute the power loss. Let it be P !loss.

12 If P !loss ≥ Ploss, declare the present reconfiguration as the best reconfiguration corresponding to tie switch n, else replace Ploss by P !loss and go to step 10.

13 i = number of iterations. If i < Stie then replace i by i + 1 and go to step 2 to repeat the program to find out the best reconfiguration corresponding to other tie switches, else go to next step.

14 Consider the current reconfiguration as the optimal reconfiguration of the distribution network and run the load flow to calculate the total technical loss (I2R), individual bus voltages, and different line flows.

15 Stop.

At last, the total technical loss (I²R) obtained during the best reconfiguration corresponding to tie switch n (n = 1, 2,…, n) and normal case load flow will be compared. Among all these n + 1 cases, the case for which the total technical loss (I²R) obtained will be minimum will be adopted as the operational network.