reaches Therefore, the control system turns off the enters in series with the DC-link and Ic. SC-FCL. rp discharges which decreases its current (time interval of till Fig. 4(c) shows the equivalent circuit Ld, t3 t4). after operation. The differential expression of is as follows: SC-FCL id whereby , , and . In the time interval of till expression is the same as (17). However, instead of t3 t4, id and their new values, and should be substituted during till respectively. Re2, Ve2, I0, Re3, Ve3, id(t3), t3 t4, Mode II-B continues up until the control system turns on the at Therefore, regarding Fig. SC-FCL t=t4. 4(a), another charging mode, the same as Mode II-A, will commence. To ensure a clear explanation, Table I is presented, showing the different modes of operation of the C-FCL with regard to Fig. 4(a). Table I: Details of operating intervals of the C-FCL after fault occurrence (t=t0). Time frame Switching state in the Operation states of the State of the The diodes in the RSC C-FCL are ON (according to Fig. 4(a)) till 000 Mode I ON All diodes t0 t1 till 100 Mode I ON All diodes t1 t2 till 100 Mode II-A ON and t2 t3 D2 D4 till 100 Mode II-B OFF and t3 t4 D2 D4 till 100 Mode II-A ON and t4 t5 D2 D4 till 100 Mode II-B OFF and t5 t6 D2 D4 till 100 Mode II-A ON and t6 t7 D2 D4 till 101 Mode I ON All diodes t7 t8 till 101 Mode II-A ON and t8 t9 D2 D4 (a)
reaches Ic. Therefore, the control system turns off the SC-FCL. rp enters in series with the DC-link and discharges Ld, which decreases its current (time interval of t3 till t4). Fig. 4(c) shows the equivalent circuit after SC-FCL operation. The differential expression of id is as follows: whereby , , and . In the time interval of t3 till t4, id expression is the same as (17). However, instead of Re2, Ve2, and I0, their new values, Re3, Ve3, and id(t3), should be substituted during t3 till t4, respectively. Mode II-B continues up until the control system turns on the SC-FCL at t=t4. Therefore, regarding Fig. 4(a), another charging mode, the same as Mode II-A, will commence. To ensure a clear explanation, Table I is presented, showing the different modes of operation of the C-FCL with regard to Fig. 4(a). Table I: Details of operating intervals of the C-FCL after fault occurrence (t=t0). Time frame (according to Fig. 4(a)) Switching state in the RSC Operation states of the C-FCL State of the The diodes in the are ON t0 till t1 000 Mode I ON All diodes t1 till t2 100 Mode I ON All diodes t2 till t3 100 Mode II-A ON D2 and D4 t3 till t4 100 Mode II-B OFF D2 and D4 t4 till t5 100 Mode II-A ON D2 and D4 t5 till t6 100 Mode II-B OFF D2 and D4 t6 till t7 100 Mode II-A ON D2 and D4 t7 till t8 101 Mode I ON All diodes t8 till t9 101 Mode II-A ON D2 and D4 (a)
IET%20Second%20Revised%20Manuscript.docx