Research on Magnetic Sensing Broadband Weak Current Sensing Technology for Broadband Voltage Inversion in Distribution Networks

The load type of distribution network is complex, the power quality is poor, and the content of harmonics and higher-order harmonics is much higher than that of high-voltage power grid. At present, electromagnetic voltage transformers are mainly used for voltage sensing in the distribution network, with small dynamic range and large high-frequency measurement errors, making it difficult to measure transient and steady-state voltages above 2kHz. The broadband voltage inversion technology based on capacities device grounding current measurement converts the measurement of voltage into non-contact measurement of capacities current, achieving indirect measurement from voltage to current and then to voltage, and obtaining broadband voltage characteristics of the distribution network. It has outstanding advantages such as not changing the primary wiring and high safety. The above scheme requires the use of non-contact methods to accurately measure mA level broadband weak current. A broadband and high-precision capacities current sensing technology based on magnetic sensing technology was proposed in this paper, providing a reliable electromagnetic inversion basis for broadband voltage sensing.