Study On Power Frequency Parameter Variable-frequency Electrical Measurement Of Transmission Line

Transmission line is an important part of power system. Line-frequency parameters of transmission consist of positive-sequence parameters, zero-sequence parameters, mutual inductance impedance and so on. All the parameters are necessary for setting the mode of the power system. Power frequency interference is an important problem of the frequency parameters measurement. It used EMTP to stimulate the power frequency interference to come to a conclusion that the power interference can affect the accuracy of measuring result seriously. It used the improved-variable frequency electrical measurement to avoid the interference. It designed the hardware circuits, including analog circuits, digital circuits with the core of 89C52, circuit of Semi-frequency signal source, and so on. Finally, we used the frequency measurement method to complete the latter part of the parameters calculation.