TRANSMISSION EQUIPMENT FOR DISTRIBUTION LINE CARRIER SIGNAL USING FREQUENCY-SWEPT SIGNAL

摘要

PURPOSE:To improve the reduction of a signal transmission error ratio due to the variation of a signal transmission characteristics of a distribution line by superposing a signal of which band is expanded by frequency sweeping synchronously with a point close to a peak point generated every half period of the voltage waveform of commercial frequency and transmitting/receiving the superposed signal. CONSTITUTION:A signal of which frequency is swept from f1 frequency up to f2 frequency within the time width of 45 deg. before and after the maximum peak value of a commercial frequency full-wave rectifying voltage to the base of a transistor (TR) 17. A pulse code bit is inputted to a linear voltage sweeping wave generator 15 to generate the input voltage waveform of a voltage controlled oscillator 16 for generating a signal of which frequency is swept from f1 frequency up to f2 frequency within 1/240sec to be bit time width. The frequency-swept wave of the oscillator 16 is inputted to the base of the switching TR 17 and current change similar to that of a sweeping frequency signal is applied to a load current with 220V low voltage to transmit the load voltage to a substation through a high voltage winding of a cylindrical transformer 6 and a high voltage distribution line.