Dual Power Switching Sensing Method for Important Load Based on Power Line Carrier Impedance Characteristics

The problem of "dual power supply single meter" refers to that the important load adopts dual power supply, but only one electric energy meter is used for electric energy measurement. It makes difficult to determine which transformer area the electric energy consumption of this load is calculated in when the dual power supply is switched. In practice, due to the lack of cooperation between various departments, the dual power supply switching of important loads in the transformer area cannot be handled in time, resulting in unqualified line loss. This paper proposes a dual power switching sensing method for important load based on power line carrier impedance characteristics. When the dual power switching occurs, the network of the important load metering point changes. The change of input impedance of measuring point is sensed through the frequency sweep signal injected, so as to realize the automatic identification of dual power switching. By setting a reasonable threshold, several groups of confirmatory experiments proved the effectiveness and scientificity of the proposed method.