A kind of overvoltage protection device that is used to prevent the insulated conductor lightning-caused breaking
Technical field
The utility model relates to the lightning protection device field, particularly a kind of overvoltage protection device that is used to prevent the insulated conductor lightning-caused breaking.
Background technology
Cause the overhead distribution fault in order to reduce external causes such as trees, birds, accumulated snow, improve power supply reliability.Developed countries has gradually adopted suspended insulated guide wire from the later stage sixties, and in Japan, overhead distribution is realized insulating basically.China also implements insulating to city overhead distribution net since the eighties and transforms pilot, has accelerated paces from the nineties, and particularly city net, upgrading of rural power grids engineering adopt the circuit of insulation in a large number in recent years.Insulated conductor has solved a series of unsafe problems that plain conductor exists, and still, thunderbolt outage problem is very outstanding.
At present, the insulated conductor bearing not stripping of insulatin layer that uses in the overhead power line of 10kv city.After the insulated conductor insulating barrier is worn by direct lightning strike or thunderbolt, form phase fault, power frequency continued flow continues finally to cause insulated conductor to blow through because of puncturing the pin hole passage place burning that forms, thereby causes the insulated conductor accident that goes offline.
Developed country adopts the time of suspended insulated guide wire power transmission and distribution longer, has accumulated a large amount of experiences.In order to reduce the thunderbolt loss of power accident rate that grows to even greater heights, successively adopted many precautionary measures and method, specific as follows:
(1) built on stilts lightning arrester
In the open space, joint use overhead ground wire to tackle distribution insulated overhead line power frequency continued flow, this is the bigger conventional method of a kind of investment.But, because the insulation level of distribution line design is lower, be very easy to cause the counterattack flashover behind the thunderbolt overhead ground wire, still can cause power frequency continued flow and blow insulated conductor.So external present less employing of this method.
(2) zinc oxide arrester
People utilize zinc oxide arrester nonlinear resistance property and the characteristic of blocking power frequency continued flow fast, are widely used in circuit with restriction thunder and lightning power frequency continued flow, and it is limited to play protection range, is merely able to protect this bar apparatus basically.Countries such as Japan, the U.S., Canada drop into huge fund circuit are transformed.After three (phase) zinc oxide arresters were installed on every basic electric pole, the thunderbolt power cut-off rate was reduced to 2.7% by original 93.3%, and the lightning-caused breaking accident does not take place basically again.When zero-clearance zinc oxide type lightning arrester was used for line thunder protection, lightning arrester directly was connected with insulated conductor, and this is the continuity of power station type lightning arrester technology, and it is reliable to have the impact energy of absorption, advantages such as discharge off time delay.
In the process that realizes the utility model, the inventor finds that there is following problem at least in prior art:
Because the insulation level of distribution line design is lower, be very easy to cause the counterattack flashover behind the thunderbolt overhead ground wire, still can cause power frequency continued flow and blow insulated conductor.Arrester without gaps is long-term because the effect of bearing lightning overvoltage and power frequency continued flow is intermittently also wanted in the effect of bearing power-frequency voltage, the lightning arrester easy ageing, so the lightning arrester accident is a lot.Because lightning arrester directly is connected with insulated conductor, when lightning arrester has an accident, may influence the normal power supply of circuit.
The utility model content
, the insulated conductor insulating barrier forms phase fault after being worn by direct lightning strike or thunderbolt in order to solve; Power frequency continued flow continues through burning because of puncturing the pin hole passage place that forms; Finally cause insulated conductor to blow; Thereby cause the go offline problem of accident of insulated conductor, the utility model embodiment provides a kind of overvoltage protection device that is used to prevent the insulated conductor lightning-caused breaking.Said technical scheme is following:
A kind of overvoltage protection device that is used to prevent the insulated conductor lightning-caused breaking, said overvoltage protection device comprises: comprise fixedly gold utensil, current limiting element, striking ball, mounting bracket up and down; Wherein, Said mounting bracket is installed in the place, steel angle of insulator; Said current limiting element is installed on the said mounting bracket, and said striking ball down is installed in said current limiting element upper end, and said upward striking ball is installed in a side lower end of said fixedly gold utensil; Be provided with discharging gap between the striking ball about said, said fixedly gold utensil is fixed on said insulator and the lead.
Further, said current limiting element is specially the zinc oxide current limiting element.
Further, said overvoltage protection device is installed in said lead fixed and puts not stripping of insulatin layer place, to bear lightning overvoltage, avoids the insulated conductor of burning.
The beneficial effect of the technical scheme that the utility model embodiment provides is: the utility model is employed in not stripping of insulatin of insulated conductor fixing point layer, has installed overvoltage protection device additional, when making lightning overvoltage not reach insulator arc-over as yet; Gap between the striking ball begins discharge up and down; Afterwards thunder and lightning power frequency continued flow guiding current limiting element is discharged, power frequency continued flow is then blocked by current limiting element, avoids blowing insulated conductor; And do not destroy any insulating barrier of insulated conductor; And connect together insulator and insulated conductor effectively, promptly guaranteed the line insulation performance, guaranteed the stable of insulated conductor again.
Description of drawings
In order to be illustrated more clearly in the technical scheme of the utility model embodiment; To do to introduce simply to the accompanying drawing that uses among the embodiment below; Obviously, below listed accompanying drawing only be some embodiment of the utility model, for those of ordinary skills; Under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is that the utility model embodiment provides a kind of structural representation that is used to prevent the overvoltage protection device of insulated conductor lightning-caused breaking.
In the accompanying drawing 1, the component list of each label representative is following:
1 fixing gold utensil; 2 current limiting elements; Striking ball about in the of 3; 4 mounting brackets.
Embodiment
For the purpose, technical scheme and the advantage that make the utility model is clearer, will combine accompanying drawing that the utility model execution mode is done to describe in detail further below.
Embodiment:
As shown in Figure 1, a kind of overvoltage protection device that is used to prevent the insulated conductor lightning-caused breaking, fixedly gold utensil 1, current limiting element 2, striking ball 3, mounting bracket 4 up and down; This overvoltage protection device is installed in the load side of line insulator; Mounting bracket 4 is installed in the place, steel angle of insulator; Zinc oxide current limiting element 2 is installed on the mounting bracket 4, and following striking ball 3 is installed in the upper end of zinc oxide current limiting element 2, and last striking ball 3 is installed in a fixedly side lower end of gold utensil; Fixedly gold utensil 1 is fixed on insulator and the lead, sets discharging gap between the striking ball up and down.
When thunderbolt took place, when lightning overvoltage did not reach insulator arc-over as yet, the gap between the striking ball began discharge up and down, afterwards thunder and lightning power frequency continued flow guiding current limiting element was discharged, and power frequency continued flow is then blocked by current limiting element, reaches the purpose of " taking shelter from the thunder ".When power-frequency overvoltage (Millisecond) appearred in short-term in transmission line, even circuit is in weak insulation (power frequency withstand 38kV), current limiting element still guaranteed discharge; Play a protective role; Thereby prevent that because of power frequency continued flow high temperature causes blowing insulated conductor and insulator arc-over, said fixedly gold utensil does not destroy any insulating barrier of insulated conductor, and connect together insulator and insulated conductor effectively; Promptly guarantee the line insulation performance, guaranteed the stable of insulated conductor again.
A kind of overvoltage protection device that is used to prevent the insulated conductor lightning-caused breaking, its installation method is:
(1) at first mounting bracket 4 is installed in place, steel insulator pin angle;
(2) zinc oxide current limiting element 2 is installed on the mounting bracket 4;
(3) will descend striking ball 3 to be installed in zinc oxide current limiting element 2 upper ends;
(4) will go up striking ball 3 and be installed in fixedly gold utensil one side lower end;
(5) fixedly gold utensil 1 is fixed on insulator and the lead;
(6) adjust the striking discharging gap.
The action principle of above-mentioned overvoltage protection device is: this product is installed in the load side of line insulator, and mounting bracket 4 is installed in place, steel insulator pin angle, and zinc oxide current limiting element 2 is installed on the mounting bracket 4; Following striking ball 3 is installed in zinc oxide current limiting element 2 upper ends; Last striking ball 3 is installed in fixedly gold utensil one side lower end, and fixedly gold utensil 1 is fixed on insulator and the lead, sets discharging gap between the striking ball up and down; When thunderbolt takes place; When lightning overvoltage did not reach insulator arc-over as yet, the gap between the striking ball began discharge up and down, afterwards thunder and lightning power frequency continued flow guiding current limiting element was discharged; Power frequency continued flow is then blocked by current limiting element, reaches the purpose of " taking shelter from the thunder ".When power-frequency overvoltage (Millisecond) appearred in short-term in transmission line, even circuit is in weak insulation, current limiting element still guaranteed discharge, plays a protective role, thereby prevents to cause blowing insulated conductor and insulator arc-over because of power frequency continued flow high temperature.
The utility model is employed in not stripping of insulatin of insulated conductor fixing point layer and has installed overvoltage protection device additional; When making lightning overvoltage not reach insulator arc-over as yet; Gap between the striking ball begins discharge up and down; Afterwards thunder and lightning power frequency continued flow guiding current limiting element is discharged, power frequency continued flow is then blocked by current limiting element, reaches the purpose of " taking shelter from the thunder ".When power-frequency overvoltage (Millisecond) appearred in short-term in transmission line, even circuit is in weak insulation, current limiting element still guaranteed discharge, plays a protective role, thereby prevents to cause blowing insulated conductor and insulator arc-over because of power frequency continued flow high temperature.Do not destroy any insulating barrier of insulated conductor, guaranteed the line insulation performance.
The utility model is employed in not stripping of insulatin of insulated conductor fixing point layer, has installed overvoltage protection device additional, when making lightning overvoltage not reach insulator arc-over as yet; Gap between the striking ball begins discharge up and down; Afterwards thunder and lightning power frequency continued flow guiding current limiting element is discharged, power frequency continued flow is then blocked by current limiting element, avoids blowing insulated conductor; And do not destroy any insulating barrier of insulated conductor; And connect together insulator and insulated conductor effectively, promptly guaranteed the line insulation performance, guaranteed the stable of insulated conductor again.
The above is merely the preferred embodiment of the utility model, and is in order to restriction the utility model, not all within the spirit and principle of the utility model, any modification of being done, is equal to replacement, improvement etc., all should be included within the protection range of the utility model.