In order to meet the test of the moter trainset

guarantee the power quality of traction substation

eliminate the effect of negative sequence current

and give full play to the transfer capability of electric power system

the traction transformer and dynamic balance-compensation equipment（TSC+TCR）are cooperated on the traction power system

which is studied in this paper. After the introduction of present problems in test system

the scheme design of three-phase balance-compensation and its working principle

the dynamic balance-compensation equipment based on combination of TSC and TSR are developed. With perfect compensation current waveform

TSC+TCR compensation mode is suit for single-phase or three-phase traction transformer

in which load current can be compensated steplessly by compensation equipment

and both system reliability and safety are improved.