Power grid ground leakage protection sensor

Abstract

The invention provides a power grid ground leakage protection sensor and relates to the electric power supply control device field. On a technology aspect, 10 power grid ground leakage detection current automation control circuits Z and 6 power grid ground leakage backflow isolation circuits H are designed. The needed circuits in the above two kinds of circuits can be selected to be mutually combined and a power grid ground leakage detection channel is created so that the power grid ground leakage protection sensor is formed. In a mechanical structure, electronic circuits are divided and are used to form plates; combination is performed and a shell is installed; glue packaging is performed so as to make a module and form an electrical element; damages because of dampness, pollution, wearing, corrosion and vibration of the circuit are prevented and an influence of an electromagnetic interference is reduced. The power grid ground leakage protection sensor is taken as a core component so that a power grid ground leakage protector with high reliability can be made. The sensor is suitable for various occasions where ground connection is not performed purposely and a power supply and consumption system with a plurality of voltage grades. A ground connection fault which is generated at any position in the power grid can be timely detected and alarm and trouble shooting are performed so as to realize a goal that the power grid and the ground maintain insulation hanging operation.

Description

1. Technical field [0001] The invention relates to the field of power supply control devices, in particular to a power grid ground leakage protection sensor. 2. Background technology [0002] After investigation and research, we learned that the neutral points of most low-voltage distribution networks in my country are artificially grounded. [0003] It is also learned that over time, ground faults in the distribution network are inevitable, and ground faults can exist for a long time. [0004] In the same power distribution system, due to the grounding of the distribution network, the earth becomes one pole of the power supply. Between the artificial grounding, the ground fault and the ground fault, the two poles of the power supply are connected through the earth, forming the so-called "same network with different lines at the same time". Grounding" is the phenomenon of "similarity, difference and difference". This is the basic principle, essence and direct cause of prob...

AI Technical Summary

Problems solved by technology

If the leakage protector is late and refuses to move for some reason, it may cause disastrous consequences

[0013] Second, the repeated grounding of the zero line causes the leakage current to shunt and refuse to move.

Due to the grounding of the neutral point of the distribution network, the leakage protector has no effect on the repeated ground faults of the neutral line of the distribution network under its jurisdiction. In addition, the ground fault is inevitable, frequent, and can exist for a long time, which will inevitably cause the accumulation of ground faults. At this time, if there is an electric shock or a ground fault on the phase line, the ground current will flow back on the spot below the leakage protector through the ground fault point of the neutral line (equivalent to the load current), causing the residual current to shunt, reducing the detection signal, and causing leakage The protector refuses to move

[0014] The third is that the leakage protector is seriously damaged due to lightning overvoltage

Since the neutral point is grounded, the zero-N line of the distribution network is almost at the same potential as the ground, and the lightning voltage is introduced between the phase and the zero-N line of the distribution network, and the circuit board of the leakage protector has poor overvoltage resistance, and most Connected between the phase and neutral wires of the power grid, it is very easy to be damaged by lightning strikes

[0015] Fourth, the technical scheme of leakage protector is contradictory

Therefore, the name of the leakage protector is a bit misleading, and it is easy to cause misunderstandings.

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