Possibilities to realize and introduce a bidirectional power flow substations forurban traction drive is described in this paper. Reconstruction of substations can be provided substituting a diodes in rectifier schemes with thyristors operating in two directions. In connection with commutation restrictions which are tied with extremevalue of inverter’s current a maximal value of delay angle in invertation regime must be lowered. Here is recommended this value as 1500. Such a principle allows simplified construction of control equipment. Newertheless lowered value of delay angle requests lowered value of inverters contrEMF also. It means that must be either lowered input voltage of inverter or largened a contrEMF. First measure can be provided applying on input of inverte BUCK type pulse converter controlled by invertor’s input current. The second measure can be provided for instace applying an extra transformer of lowered rated power a secondary windings of which are set in series with ones of governor transformer. The both kinds of rezitation schemes are examined applying computer modelling tools and are well operating in transient processes.