The efficiency of the recuperative braking of DC electric rolling stock is analyzed in the article. The monitoring of voltages and currents is done for EPL2T trains and VL8 locomotives in the traction and recuperative braking modes. Basic, additional and total technical losses of the recuperated energy are calculated for a DC traction power system. The statistical and theoretical distributions of the RMS current, the additional and total losses are drawn, and their basic probabilistic coefficients are calculated.

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