A method for detecting and compensating for a false data injection cyber-attack on an electrical substation including a merging unit (MU), a phasor measurement unit (PMU), and a substation phasor data concentrator (ssPDC), the method comprising: operating the PMU to receive input from at least one of a current transformer of the electrical substation, a voltage transformer of the electrical substation and a circuit breaker of the electrical substation and to provide a PMU measurement output based upon the received input, the PMU measurement output including one of a PMU current phasor, a PMU voltage phasor, and a PMU circuit breaker status indication; operating the MU to receive input from the at least one of the current transformer of the electrical substation, the voltage transformer of the electrical substation and the circuit breaker of the electrical substation and to provide an MU measurement output based upon the received input, the MU measurement output including one of an MU current phasor, an MLJ voltage phasor, and an MLT circuit breaker status indication; receiving with the ssPDC a first input indicated as the PMU measurement output and a second input indicated as the MLT measurement output and storing the first input and the second input in respective non-transitory memory locations; performing an electrical state estimation for the substation using the stored first input and the stored second input; determining, with the ssPDC, that one of the stored first input and the stored second input comprises false data based upon a discrepancy between the state estimation and the one of the stored first input and the second stored input and that another one of the stored first input and the stored second input comprises uncorrupted data; and replacing, in the memory of the ssPDC, the one of the stored first input and the stored second input which comprises false data with the other one of the stored first input and the stored second input which comprises uncorrupted data. operating the PMU to receive input from at least one of a current transformer of the electrical substation, a voltage transformer of the electrical substation and a circuit breaker of the electrical substation and to provide a PMU measurement output based upon the received input, the PMU measurement output including one of a PMU current phasor, a PMU voltage phasor, and a PMU circuit breaker status indication; operating the MU to receive input from the at least one of the current transformer of the electrical substation, the voltage transformer of the electrical substation and the circuit breaker of the electrical substation and to provide an MU measurement output based upon the received input, the MU measurement output including one of an MU current phasor, an MLJ voltage phasor, and an MLT circuit breaker status indication; receiving with the ssPDC a first input indicated as the PMU measurement output and a second input indicated as the MLT measurement output and storing the first input and the second input in respective non-transitory memory locations; performing an electrical state estimation for the substation using the stored first input and the stored second input; determining, with the ssPDC, that one of the stored first input and the stored second input comprises false data based upon a discrepancy between the state estimation and the one of the stored first input and the second stored input and that another one of the stored first input and the stored second input comprises uncorrupted data; and replacing, in the memory of the ssPDC, the one of the stored first input and the stored second input which comprises false data with the other one of the stored first input and the stored second input which comprises uncorrupted data. <EOS>