On-line energy acquisition device of automatic transformation winding based on current transformer (CT)

Abstract

The invention relates to an on-line energy acquisition device of an automatic transformation winding based on a current transformer (CT). The energy acquisition winding, which winds on the nanocrystal iron core, is utilized to transform magnetic field energy around the alternating current bus into electric energy, and the electric energy is processed by a low voltage drop rectifier circuit (1), a primary filter and voltage sampling circuit I (2), a delay comparison circuit (3), a relay drive control circuit (4), a zero voltage drop voltage regulator circuit (5) and a secondary voltage sampling and filter circuit II (6) to obtain a stable output voltage. The device of the invention can be used for transforming the magnetic field energy around the alternating current bus into the electric energy through the coupling of the magnetic circuit so as to provide stable electric energy for the state monitoring sensor nodes of the power grid line and the electrical equipment. The device of the invention is especially suitable to be used as a power supply for wireless sensor monitoring nodes of current, voltage, temperature and the like for high voltage pylon wires in remote districts, such as mountains, lake and the like.

Description

technical field [0001] The invention relates to a suspension power-taking device for a high-voltage line, in particular to a device for converting stray magnetic field energy around an AC bus bar into stable electric energy by using a small CT. Background technique [0002] In order to improve energy utilization efficiency and apply renewable energy access, the current power grid is gradually developing towards a flexible smart grid characterized by intelligent control, management and analysis, which requires various sensors to monitor the current of grid lines, Real-time monitoring of parameters such as voltage, temperature and power equipment operation. [0003] However, while we enjoy the convenience brought by electronic technology, another problem arises, that is, how to provide stable energy for these sensing devices. At present, various sensing devices used for power grid status monitoring are mostly powered by green energy (such as solar energy, wind energy, etc.) a...

AI Technical Summary

Problems solved by technology

[0005] One of the difficulties in the application of online energy harvesting devices based on CT (current transformers) is that as the bus current increases, too much energy is forcibly injected into the energy harvesting device, causing the temperature of the device to rise sharply

In order to reduce the temperature rise, there are mainly three methods adopted by the existing CT-based energy harvesting devices. One is the method of using the compensation coil, but it is essentially equivalent to transferring heat to the compensation coil, so the effect of reducing the temperature rise It is not obvious; the second is to connect a reactor or a choke coil with a large inductance value in series at the output end of the secondary winding. Or the high voltage drop at both ends of the choke coil is at the cost, which easily brings the risk of voltage breakdown to the electronic circuit in the energy-taking device; the third is to automatically change the number of winding turns by detecting the secondary winding current, which avoids The shortcomings of the first two, but the system is more complicated

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