Taking the Yuheng-Yan’an 750 k V electric transmission line for example

different ATP-EMTP models with different operation modes are built based on the actual data in 2014. Closing no-load line operation with different MOA settings and single-phase reclosing operation with different fault conditions are performed.Computation results show that: 1)in the case of equipping a reactor with 80% compensation degree

the application of only a pre-inset resistor can reduce the maximum 2% switching overvoltage to under 1.8 p.u. in the operations of closing no-load line and successful reclosing;2)when only different MOAs are equipped

the maximum 2%switching overvoltage is greater than 1.8 p.u. in the operations of closing no-load line

successful reclosing

and unsuccessful reclosing with an earth point at the reactive power sending end when the circuit Ⅱ is in normal operation condition; and 3)when a pre-inset resistor and 648 MOA at each end of the line are equipped

the maximum 2% switching overvoltage is under 1.8 p.u. in the operations of closing no-load line

successful reclosing

and unsuccessful reclosing with an earth point in the middle of the line. Consequently

it is concluded that the pre-inset resistor of circuit-breaker cannot be cancelled.