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The paper dwells on calculation method for the negative-sequence currents in the generator circuit in unbalanced conditions. The method considers shunting effect of the load, comprising asynchronous motors. It is based on a software complex for calculating electromechanical transients, designed on the basis of the single-phase network positive-sequence diagram and supplemented with straight-line negative and zero-sequence diagrams. During the electromechanical transient, diagrams of various sequences switch a circuit according to the type and point of fault. This method takes into account variation of the symmetrical periodic component, caused by sub-transient short-circuit current, the effect of automatic excitation control and change in the polar wheel angle during electromechanical transients. Calculations have shown that the load, comprising asynchronous motors, leads to decreasing negative-sequence currents in the generator circuit with various connection diagrams up to 17%. Accounting for the impact of motors allows us to specify calculations of tripping set points and sensitivity study of generator protection against the negative-sequence currents.