High-reliability big-work-range sensing energy taking device based on adjustable impedance and regulation and control method

Abstract

The invention provides a high-reliability big-work-range sensing energy taking device based on adjustable impedance. The device comprises an energy taking current transformer (energy taking CT), an adjustable impedance circuit, an AC-DC conversion circuit, a storage battery and a supercapacitor energy management module and an electricity use load. By studying the influence of the secondary side load on the energy taking effect, the mathematical relationship of the active power output by the energy taking CT and the secondary side impedance is built. A method of connecting the adjustable impedance at the secondary side in parallel is used; the obtaining of the required power output when the primary side current changes in a large range is realized through regulating the adjustable impedance. Through a parallel connection resonance mode, the energy CT primary side current threshold value lower limit is reduced; the primary side current threshold value upper limit is improved in an adjustable impedance flow division mode, so that the work range of the energy taking CT can be expanded. The output of the required target power under the condition of large-range fluctuation of the primaryside current of the energy taking CT can be realized according to the mathematical relationship between the output power and the secondary side impedance.

Description

technical field [0001] The invention relates to the technical field of power supply applied to an on-line monitoring system of a transmission line, in particular to an adjustable impedance-based high-reliability and large-working-range induction energy harvesting device and a control method. Background technique [0002] With the rapid development of smart grids, the voltage level and transmission capacity of power system transmission lines are constantly improving. On-line monitoring of the operating status of high-voltage transmission lines and accurate positioning of line faults have attracted more and more attention. In a high-voltage, strong electromagnetic environment, a stable and reliable power supply is the premise and basis for the long-term stable operation of the online monitoring device. [0003] In recent years, Chinese and foreign scholars have conducted a large number of fruitful researches on the power supply of transmission line on-line monitoring devices. ...

AI Technical Summary

Problems solved by technology

[0010] 2. When the current on the primary side is too large, that is: greater than the upper threshold, the magnetic circuit of the energy harvesting CT is saturated at this time, and cannot provide stable energy for the secondary side

But at the same time, it also brings many unfavorable factors such as large iron core volume, frequent battery charging and discharging, battery life limit, etc., which adversely affects the application range, cost and operation reliability of the entire energy harvesting device.

Images