A system, method, and apparatus are described for monitoring the operation of a three phase system. In some embodiments, one or more vectors may be generated. The vectors may be indicative of an output of the three phase system. In some embodiments, one or more of the vectors may correspond to a difference of two of the three phases of the three phase system. A gain associated with a third of the vectors may be different from a gain associated with each of the first and the second vectors. The gain associated with the third vector may be maximized. The three vectors may be combined with hardware or software. In some embodiments, frequency content associated with the three phase system may be filtered with hardware or software. For example, filtering may be used to remove frequencies outside of a specified frequency range of interest.