CN2593440Y

CN2593440Y - Overvoltage protection apparatus

Info

Publication number: CN2593440Y
Application number: CN 03232771
Authority: CN
Inventors: 栾建川
Original assignee: CISDI Engineering Co Ltd
Current assignee: CISDI Engineering Co Ltd
Priority date: 2003-01-09
Filing date: 2003-01-09
Publication date: 2003-12-17
Anticipated expiration: 2013-01-09

Abstract

The utility model discloses an overvoltage protection apparatus which is a novel combined overvoltage protection apparatus relating to electric apparatus in an electric power system. The apparatus comprises four branches which are connected into a tetraster shape, wherein, branches, one end of which is connected with phase wires A, B, and C, are connected in series with a resistor through capacitors, and then are connected in parallel with a zinc-oxide nonlinear resistor, and finally are connected in series with a gap, one end of the fourth branch is connected with an earth wire, the fourth branch is connected in parallel with the zinc-oxide nonlinear resistor through a capacitor and then is connected in series with the gap, and the other end of the four branches is connected together. The utility model is suitable for isolated neutral systems of 35KV, 10KV, and 6KV, can be used for overvoltage protection of electric apparatus in electric power systems, and has a good overvoltage protection effect.

Description

A kind of overvoltage protection

Technical field

The utility model is a kind of novel combination type overvoltage protection that relates to the electric power system electric equipment.

Background technology

According to the Technological Economy of electric equipment and electric pressure, the insulation of high voltage electric apparatus (as power distribution equipment, transformer, motor etc.) all has certain limit.For avoiding the harm of atmospheric over-voltage and switching overvoltage to these equipment, in the prior art, have and adopt the band (seeing accompanying drawing 1) and the zinc oxide arrester device of the four stars type wiring of band gap not, employing RC capacitance-resistance absorption plant is also arranged.Have certain effect to a certain extent with in the certain limit to preventing overvoltage though the former shortcoming is it, because self electrical characteristic of znr, it is slower to high frequency overvoltage signal response speed.When switching overvoltage or other overvoltage take place, can not reduce the rising steepness of frequency of oscillation and overvoltage wave head, can not damping and decay overvoltage oscillations.In addition, the wave head of high frequency and high steepness also has harmful effect to zinc oxide arrester itself, thereby has caused frequent the electric equipment particularly damage of motor windings turn-to-turn insulation and the damage of zinc oxide arrester protective device self.Though and the latter's shortcoming be it to prevent overvoltage to a certain extent with have certain effect in the certain limit, but because self-characteristic can not be reduced to overvoltage a definite level, the overvoltage energy that can not release big rapidly, but come oscillatory extinction to fall the overvoltage wave energy by the equivalent resistance of resistance and system, thereby caused the particularly damage of motor windings turn-to-turn insulation of frequent electric equipment, RC capacitance-resistance absorption plant has also taken place often can not bear in some cases than the overvoltage of macro-energy and impact and the accident of blast.

Summary of the invention

The purpose of the utility model device is to provide a kind of novel combination type overvoltage protection device, to overcome the insurmountable difficult problem of above-mentioned prior art.

For achieving the above object, the technical solution that the utility model device is provided is in parallel with the znr valve block after capacitor is connected with resistance, connects with the gap, thereby constitutes a standard branch.The 4th branch road then by capacitor be composed in series with the gap again after znr is in parallel.And then be connected into the four stars type by three standard branches and the 4th branch road, and promptly one of three standard branches being terminated at A, B, C phase line, the 4th branch road one is terminated at ground wire G, and the other end of four branch roads is connected together, and forms a mid point.

After system or electric equipment adopt this device,, efficiently solve the Over-voltage Protection of electric equipment according to its mode of connection and operation principle.When switching overvoltage or the generation of other overvoltage, gap breakdown.After the puncture; RC loop and znr valve block insert oscillation circuit immediately simultaneously; effectively reduce frequency of oscillation and overvoltage wave head rising steepness; protected the turn-to-turn insulation of electric equipment; the also effectively damping and the superpotential vibration that decayed; rapidly the overvoltage amplitude is lowered and be limited in certain voltage levvl (because this device has clear and definite residual voltage value; also clear and definite this protective device is to superpotential protective capability), also can rapidly big overvoltage energy be released by the znr with big discharge capacity.In addition because gapped; under situations such as normal or single-phase earthing; the gap effectively isolates protection component and system; the chargeability that makes znr is zero; also make capacitor not be subjected to influence of harmonic in the electrical network; prolonged the life-span of device, capacitor under normal circumstances can not provide capacitance current to system yet.RC loop and znr in the device also play a part mutual protection.Because this device has also adopted the four stars type mode of connection, has effectively protected relatively to reach alternate overvoltage.

Description of drawings

Fig. 1 is the mode of connection of lightning arrester in the prior art.

Fig. 2 is the utility model structural representation.

Embodiment

Below in conjunction with accompanying drawing embodiment of the present utility model is described in further detail.

Referring to accompanying drawing 1,2, number in the figure: CG1, CG2, CG3, CG4 are the gap, and FR1, FR2, FR3, FR4 are znr, and C1, C2, C3, C4 are capacitor, and R1, R2, R3 are resistance.A, B, C are phase line, and G is a ground wire.

Referring to accompanying drawing 2, C1 connects with R1 (C2 and R2, C3 and R3), and is in parallel with FR1 (FR2, FR3) again, connects with CG1 (CG2, CG3) again, forms a standard branch.C4 is in parallel with FR4, connects with CG4 again, forms the 4th branch road.One end of three standard branches is connected with A, B, C phase line respectively, and an end of the 4th branch road links to each other with ground wire, and the other end of four branch roads links together, and forms a mid point.Its feature be with the RC capacitance-resistance absorb with znr effective in parallel after, again by a gap access electrical network.RC loop and znr in the device also play a part mutual protection.Because this device has also adopted the four stars type mode of connection, has effectively protected relatively to reach alternate overvoltage.

The utility model is applicable to 35KV, 10KV, 6KV isolated neutral system.

Claims

1. overvoltage protection, this device comprises four branch roads that are connected into the four stars type, it is characterized in that wherein a route capacitor that is terminated at A, B, C phase line connects afterwards in parallelly with znr with resistance, connects with the gap more at last; One the 4th branch road that is terminated at ground wire is then connected with the gap by after capacitor and the znr parallel connection again; Article four, the other end of branch road then is connected together.