Apparatus and method for obtaining electricity from high voltage electric cable

Abstract

The invention relates to a device and a method for getting power directly from a high-voltage cable, which is used for getting the electric energy directly from the primary bus current at the high-voltage side through a current mutual inductor. The device comprises a current mutual inductor, a high-voltage protection circuit, a rectifier bridge, an energy release circuit, a voltage stabilization block and a filtering circuit. Since the high-voltage protection circuit is additionally arranged between the current mutual inductor and the rectifier bridge, the induced voltage applied to the rectifier bridge is greatly reduced, the output current of the current mutual inductor is limited, and the invention plays the roles of stabilizing the voltage and the protecting the subsequent circuit andsuccessfully solve the problem of the power supply of the high-voltage side active electronic device.

Description

【Technical field】 [0001] The present invention relates to a device and method for taking electricity, in particular to a device and method for taking electricity from a high-voltage cable through a current transformer (CT, Current Transformer). 【Background technique】 [0002] The terminals of high-voltage cables are usually in the wild or in unattended areas, and it is often difficult to obtain the low-voltage power supply required for the system's collection terminals to work. Therefore, the power supply of the collection terminals has become a major problem in system design. Without a safe and reliable power supply, it is impossible to guarantee the accuracy and reliability of terminal data collection and transmission. [0003] At present, the electric energy of outdoor low-voltage equipment is mainly obtained through the following methods: [0004] 1. Use the current transformer to take power from the bus: [0005] The basic idea of ​​a typical circuit that uses a curre...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that due to the limitation of laser output power, especially the influence of photocell conversion efficiency, the energy provided by this method is limited, so the high-voltage side circuit is required to design micro-power consumption, which increases the circuit design. Difficulty, at the same time, compared with the previous two methods, the design cost is higher

The disadvantage of this method is that the output power is unstable, which is determined by the inherent defects of solar cells, and is easily affected by factors such as light intensity, external environment temperature changes, and seasonal changes; The energy provided by the method is limited, which limits its application; at the same time, the high design cost is also a factor that limits its wide application

However, there are still many problems in terms of manufacturing cost and reliability by adopting such a method.

[0014] From the above analysis, it can be seen that the use of current transformers to obtain power from the bus mainly has problems when the cable operating current is too small, the obtained power cannot meet the needs, and how to protect the power-taking device when the current is too large; The voltage divider mainly has the stability and reliability problems of the power-taking device from the busbar; the laser energy supply mainly has the problems of low laser output power, low conversion efficiency of photocells, and limited energy provided; the solar power supply mainly has the problem of output The power supply is unstable and affected by the weather; the main battery power supply has the problem that the life of the battery is relatively short and it is difficult to replace it

Judging from the current power supply situation of the data acquisition terminal of the high-voltage cable online monitoring system, there are certain problems in using the above-mentioned methods, so there is an urgent need for a method that can directly obtain sufficient electric energy from the cable and ensure reliable and safe power extraction. device

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