CN105826848B - Power station grounded screen - Google Patents

The disclosure discloses a kind of power station grounded screen, belongs to electric field.The power station grounded screen includes：Grid side grounded screen and plant side grounded screen；The grid side grounded screen electrically connects with the earth point of the neutral point for the main transformer that boosts, and the grid side grounded screen electrically connects with the earth point of the first equipment, and first equipment includes the equipment being directly connected to power network；The plant side grounded screen electrically connects with the earth point of the second equipment, and second equipment includes the equipment that working power is provided by power station；Without electrically connecting between the grid side grounded screen and the plant side grounded screen.Harm of the earth-current to power station boosting main transformer is alleviated, has reached the effect for improving power network and power station security.

Power station grounded screen

Technical field

This disclosure relates to electric field, more particularly to a kind of power station grounded screen.

Background technology

Earth-current generally existing in power network, such as, boost main transformer neutral point out-of-balance current, geomagnetic induction current And it is other in the case of caused earth-current, and very big safety to power station and power station staff to be all present hidden for earth-current Suffer from.Therefore, potential safety hazard is produced, it is necessary to be let out to earth-current to power station and power station staff in order to reduce earth-current Stream.

Earth-current aerial drainage is realized in the following way at present：Each power station includes a grounded screen, the ground connection netting gear There is conductive capability, the electric current for accessing the grounded screen can be injected the earth, by the boosting main transformer by the power station Property point earth point, the earth point of power station station equipment, the earth point and miscellaneous equipment of the equipment being directly connected to grid side Earth point be connected in the grounded screen so that each earth-current pass through the grounded screen complete aerial drainage.

Inventor has found that correlation technique at least has following defect during the disclosure is realized：

Because the composition material of the grounded screen in each power station is not quite similar, cause the ground connection of the grounded screen in each power station Effect is also different, and then causes earth-current more to carry out aerial drainage by the grounded screen in the preferable power station of earthing effect.Now, Earth-current on power network can flow through the main transformer winding in the preferable power station of the earthing effect by overhead transmission line so that main transformer direct current Magnetic bias, increases noise, and longtime running influences Transformer Winding insulation, when serious, causes dielectric breakdown accident, and then cause this to connect Larger potential safety hazard be present in the preferable power station of ground effect.

The content of the invention

In order to solve problem present in correlation technique, the disclosure provides a kind of power station grounded screen.The power station connects Earth mat includes：Grid side grounded screen and plant side grounded screen；

The grid side grounded screen electrically connects with the earth point of the neutral point for the main transformer that boosts, the grid side grounded screen Electrically connected with the earth point of the first equipment, first equipment includes the equipment directly electrically connected with power network；

The plant side grounded screen electrically connects with the earth point of the second equipment, second equipment include working power by The equipment that power station provides；

Without electrically connecting between the grid side grounded screen and the plant side grounded screen.

Optionally, the grid side grounded screen and the distance at the plant side grounded screen interval are more than or equal to non-interference Distance, non-interference distance for the grid side grounded screen and the plant side grounded screen do not produce electromagnetic interference away from From.

Optionally, the non-interference distance is 20 meters.

Optionally, the plant side grounded screen electrically connects with the earth point of voltage transformer secondary side, the power station Side joint earth mat electrically connects with the earth point of voltage transformer secondary cable shield.

Optionally, the plant side grounded screen electrically connects with the earth point of Current Transformer Secondary side, the power station Side joint earth mat electrically connects with the earth point of Current Transformer Secondary cable shield.

Optionally, the grid side grounded screen includes the first bus-bar, and first bus-bar is electrically connected including one first End and at least one second electric connecting terminal are connect, first electric connecting terminal is connected with least one second electric connecting terminal, institute Each electric connecting terminal stated at least one second electric connecting terminal is in parallel, and each electric connecting terminal is used to connect a ground connection Point；

The grid side grounded screen and the first electric connecting terminal electricity in succession, the earth point of the neutral point with it is described at least Electric connecting terminal electrical connection in one the second electric connecting terminal, the earth point of each first equipment with it is described at least one Electric connecting terminal electrical connection in second electric connecting terminal.

Optionally, the power station grounded screen includes the second bus-bar, and second bus-bar is electrically connected including one the 3rd End and at least one 4th electric connecting terminal are connect, the 3rd electric connecting terminal is connected with least one 4th electric connecting terminal, institute Each electric connecting terminal stated at least one 4th electric connecting terminal is in parallel, and each electric connecting terminal is used to connect a ground connection Point；

The plant side grounded screen electrically connects with the 3rd electric connecting terminal, the earth point of each second equipment with Electric connecting terminal electrical connection at least one 4th electric connecting terminal；

The plant side grounded screen electrically connects with the 3rd electric connecting terminal, the ground connection of the voltage transformer secondary side Point electrically connects with an electric connecting terminal at least one 4th electric connecting terminal；

The earth point of the voltage transformer secondary cable shield and one at least one 4th electric connecting terminal Individual electric connecting terminal electrical connection.

Optionally, the power station grounded screen includes the second bus-bar, and second bus-bar is electrically connected including one the 3rd End and at least one 4th electric connecting terminal are connect, the 3rd electric connecting terminal is connected with least one 4th electric connecting terminal, institute Each electric connecting terminal stated at least one 4th electric connecting terminal is in parallel, and each electric connecting terminal is used to connect a ground connection Point；

The plant side grounded screen electrically connects with the 3rd electric connecting terminal, the earth point of each second equipment with Electric connecting terminal electrical connection at least one 4th electric connecting terminal；

The plant side grounded screen electrically connects with the 3rd electric connecting terminal, the ground connection of the Current Transformer Secondary side Point electrically connects with an electric connecting terminal at least one 4th electric connecting terminal；

The earth point of the Current Transformer Secondary cable shield and one at least one 4th electric connecting terminal Individual electric connecting terminal electrical connection.

Optionally, the neutral point includes the Y type neutral points of the boosting main transformer directly electrically connected with power network, the electricity Net side grounded screen electrically connects with the earth point of the Y types neutral point.

The technical scheme provided by this disclosed embodiment can include the following benefits：

The power station grounded screen provided in the embodiment of the present disclosure includes grid side grounded screen and plant side grounded screen, and Therebetween without electrical connection.Therefore, when laying the grid side grounded screen, generally it is convenient to select lay the grid side grounded screen Position, thus it is same or like with other grid side grounded screens on power network that preferably the grid side grounded screen can be laid in Environment in, and then cause in the grid side grounded screen and power network other each grid side grounded screens have it is same or like over the ground Resistance, and then the flowing of earth-current on power network is reduced, so as to reduce the ground electricity for flowing through step-up transformer main transformer winding and neutral point Stream, and then harm of the earth-current to power station boosting main transformer is alleviated, reach the security for improving power network and power station Effect.

It should be appreciated that the general description and following detailed description of the above are only exemplary, this can not be limited It is open.

Brief description of the drawings

Accompanying drawing herein is merged in specification and forms the part of this specification, shows the implementation for meeting the disclosure Example, and be used in specification to explain the principle of the disclosure together.

Figure 1A is a kind of block diagram of power station grounded screen according to an exemplary embodiment；

Figure 1B is a kind of schematic diagram of power station grounded screen according to another exemplary embodiment；

Fig. 2 is a kind of voltage transformer secondary side summation current transformer secondary side according to another exemplary embodiment The schematic diagram of sending and receiving power station side joint earth mat；

Fig. 3 is a kind of the voltage transformer secondary cable shield and Current Mutual Inductance according to another exemplary embodiment The schematic diagram of device secondary cable shielding layer sending and receiving power station side joint earth mat；

Fig. 4 is and a kind of schematic diagram of grounded screen including bus-bar according to an exemplary embodiment.

Embodiment

Here exemplary embodiment will be illustrated in detail, its example is illustrated in the accompanying drawings.Following description is related to During accompanying drawing, unless otherwise indicated, the same numbers in different accompanying drawings represent same or analogous key element.Following exemplary embodiment Described in embodiment do not represent all embodiments consistent with the disclosure.On the contrary, they be only with it is such as appended The example of the consistent apparatus and method of some aspects be described in detail in claims, the disclosure.

Figure 1A is a kind of power station grounded screen G exemplified according to exemplary partial implementation schematic diagram, as shown in Figure 1A, Power station grounded screen G can include grid side grounded screen G1 and plant side grounded screen G2.

Power station grounded screen G can be used for earth-current present in the equipment that aerial drainage power station includes, so the power station Grounded screen G electrically connects with there may be the equipment of earth-current in power station plant, with the earth-current in aerial drainage these equipment.

The mode or equipment for producing earth-current may include：The neutral point uneven electricity that may be present of boosting main transformer Flow, may cause to deposit in these equipment due to other reasons such as insulation breakdown, electromagnetic induction with the equipment that power network directly electrically connects Electric current, and the equipment that working power is provided by power station may also be due to other reasons such as insulation breakdown, electromagnetic induction Cause in these equipment there is also electric current.

Further, it is a kind of schematic diagram of power station grounded screen referring to Figure 1B, in Figure 1B, the power station grounded screen can be with Including following equipment：Boost main transformer 1, the neutral point 2 for the main transformer 1 that boosts, the first equipment 3, the second equipment 4, generator 5 (and one kind of the second equipment 4), first equipment 3 may include the equipment directly electrically connected with power network, and second equipment 4 includes The equipment that working power is provided by power station.

In addition, W, Y, Z be the boosting main transformer 1 to the three-phase bus after the boost in voltage in power station.Boosting master The three-phase line of transformer 1 and the outlet side of generator 5 is delta connection (can also be star connection), with grid side without being electrically connected Connect, the neutral point 2 of boosting main transformer 1 is wye connection.

Grid side grounded screen G1 and the plant side grounded screen G2 that power station grounded screen G includes include with power station Equipment connected by following connected mode：

The grid side grounded screen G1 electrically connects with the earth point of the neutral point 2, grid side grounded screen G1 also with this first The earth point electrical connection of equipment 3.

The plant side grounded screen G2 electrically connects with the earth point of second equipment 4.

Without electrically connecting between the grid side grounded screen G1 and plant side grounded screen G2.

In the present embodiment, as shown in figure 1 a or figure 1b, power station grounded screen G can include grid side grounded screen G1 With the plant side grounded screen two grounded screens of G2.In this way, G1 and G2 points are opened, it may be such that grid side grounded screen G1 can be according to need Be laid in its suitable laying place.Such as may be selected with power network on other grid side grounded screens have it is same or like Lay environment so that the resistance to earth of each grid side grounded screen is same or like on power network, and then reduces earth-current on power network Flowing, so as to reduce flow through boosting main transformer 1 main transformer winding and neutral point 2 earth-current, and then improve power network and The security in power station.

Optionally, the neutral point 2 also includes the delta-type neutral point directly electrically connected with power network.

Optionally, in order that not producing electromagnetic interference between the grid side grounded screen G1 and plant side grounded screen G2, The distance being spaced between the grid side grounded screen G1 and plant side grounded screen G2 is more than or equal to non-interference distance, and this is non-dry Disturb the distance that distance does not produce electromagnetic interference for the as grid side grounded screen G1 and plant side grounded screen G2.

In addition, the non-interference distance can be determined according to power station grounded screen G actual conditions, such as, when this When the grid side grounded screen G1 in power station and plant side grounded screen G2 laying areas are larger, non-interference distance can be determined For a larger distance, such as it is defined as 40 meters, as the grid side grounded screen G1 and the plant side grounded screen in the power station When G2 laying areas are smaller, the non-interference distance can be defined as to a less distance, such as be defined as 10 meters or 20 meters. Here it is not specifically limited.

In addition, when the power station is in coastal (such as Nuclear Power Station, Nuclear Power Station is mostly in coastal), due to seawater With certain electric conductivity, so when laying the grounded screen in power station, the grid side grounded screen G1 in the power station and seashore Distance is more than or equal to non-electric-connecting distance, to avoid the grid side grounded screen G1 and plant side grounded screen G2 from passing through seawater Electrical connection is realized, the non-electric-connecting distance refers to the grid side grounded screen G1 and plant side grounded screen G2 can not be real by seawater The distance now electrically connected.

In addition, for voltage transformer summation current transformer, grounded screen can be electrically connected in the following way：

For voltage transformer, its side joint is in high-pressure system, if the first and second of the voltage transformer in operation The insulation damages of side, primary side high pressure will scurry into secondary side, not only damage the safety that secondary side apparatus also threatens staff. Therefore, the secondary side of voltage transformer needs one point earth.Electrically connected to be not present with grid side grounded screen G1, referring to figure The earth point of 2, plant side grounded screen G2 also with voltage transformer secondary side 6 electrically connects.In addition, in order to further protect electricity Press transformer, improve the security in power station, referring to Fig. 3, plant side grounded screen G2 also with voltage transformer secondary cable The earth point electrical connection of screen layer 8.

For current transformer, its side joint enters high current, secondary side access low current, in order to prevent when first and second When side is broken down by high-voltage because of insulation breakdown, the high current of its primary side scurries into secondary side, so as to damage secondary side apparatus, and prestige Coerce the safety of staff.Therefore, the secondary side of current transformer needs one point earth.In order to grid side grounded screen G1 not In the presence of electrical connection, referring to Fig. 2, earth points of the plant side grounded screen G2 also with Current Transformer Secondary side 7 electrically connects, in order to Further improve the security of secondary side, referring to Fig. 3, plant side grounded screen G2 also with Current Transformer Secondary cable shield The earth point electrical connection of layer 9.

Further, since the voltage transformer primary side and the current transformer primary side are directly connected with power network, and power network Directly electrically connected with the neutral point 2 of the boosting main transformer 1, and the earth point electrical connection of the neutral point 2 of the boosting main transformer 1 Grid side grounded screen G1, thus the voltage transformer primary side and the current transformer primary side indirectly with grid side grounded screen G1 is electrically connected, thus without electrically connecting grounded screen again.

Optionally, the first bus-bar 10, first bus-bar 10 can also be included referring to Fig. 4, grid side grounded screen G1 Including first electric connecting terminal 11 and at least one second electric connecting terminal 12, first electric connecting terminal 11 with this at least one the Two electric connecting terminals 12 are connected, and each electric connecting terminal at least one second electric connecting terminal 12 is in parallel, and each electric connecting terminal For connecting an earth point.

In addition, referring still to Fig. 4, it can realize that the neutral point 2 electrically connects with grid side grounded screen G1 by the following method, with And first equipment 3 electrically connects with grid side grounded screen G1：

The grid side grounded screen G1 with the electricity of first electric connecting terminal 11 in succession, the earth point of the neutral point 2 with this at least one Electric connecting terminal electrical connection in individual second electric connecting terminal 12, the earth point of each first equipment 3 with this at least one the Electric connecting terminal electrical connection in two electric connecting terminals 12.

Optionally, the second bus-bar 20 is also included referring still to Fig. 4, power station grounded screen G, second bus-bar 20 wraps Include the 3rd electric connecting terminal 21 and at least one 4th electric connecting terminal 22, the 3rd electric connecting terminal 21 with this at least one 4th Electric connecting terminal 22 is connected, and each electric connecting terminal at least one 4th electric connecting terminal 22 is in parallel, and each electric connecting terminal is used In one earth point of connection.

In addition, referring still to Fig. 4, second equipment 4 and plant side grounded screen G2 electricity can be realized by the following method Connection：

The plant side grounded screen G2 electrically connects with the 3rd electric connecting terminal 21, the earth point of each second equipment 4 with Electric connecting terminal electrical connection at least one 4th electric connecting terminal 22.

In addition, referring still to Fig. 4, the voltage transformer secondary side 6 and the power station side joint can be realized by the following method Earth mat G2 is electrically connected, and the voltage transformer secondary cable shield 8 electrically connects with plant side grounded screen G2：

The plant side grounded screen G2 electrically connects with the 3rd electric connecting terminal 21, the ground connection of the voltage transformer secondary side 6 Point electrically connects with an electric connecting terminal at least one 4th electric connecting terminal 22.The voltage transformer secondary cable shield 8 earth point electrically connects with an electric connecting terminal at least one 4th electric connecting terminal 22.

In addition, referring still to Fig. 4, the Current Transformer Secondary side 7 and the power station side joint can be realized by the following method Earth mat G2 is electrically connected, and the Current Transformer Secondary cable shield 9 electrically connects with plant side grounded screen G2：

The plant side grounded screen G2 electrically connects with the 3rd electric connecting terminal 21, the ground connection of the Current Transformer Secondary side 7 Point electrically connects with an electric connecting terminal at least one 4th electric connecting terminal 22.The Current Transformer Secondary cable shield 9 earth point electrically connects with an electric connecting terminal at least one 4th electric connecting terminal 22.

It should be noted that power station grounded screen G is also suitable for Nuclear Power Station, existing Nuclear Power Station is substantially at edge Sea, and the resistance to earth of Nuclear Power Station grounded screen is much smaller than the resistance to earth in inland power station, therefore, the earth-current of existing power network More by the grounded screen of Nuclear Power Station to sea aerial drainage, so the main transformer winding and neutral point of Nuclear Power Station are caused very big Influence, when the grounded screen included using the disclosure, the grounded screen of Nuclear Power Station is laid as grid side grounded screen and generating Stand side joint earth mat, and the grid side grounded screen is laid in and is more than or equal to the distance on seashore in the non-electric-connecting distance Land so that the Nuclear Power Station grid side grounded screen has same or like electricity over the ground with other grid side grounded screens on power network Resistance, reduce earth-current on power network and flow through the Nuclear Power Station main transformer winding and neutral point, improve the peace of power network and the Nuclear Power Station Quan Xing.

In addition, for the power station built up, the power station grounded screen that this has built up can be disclosed according to the disclosure Power station grounded screen G will be transformed, will a Grounding Network Reconstruction be by the grid side grounded screen G1 and the power station The grounded screen of side joint earth mat G2 compositions.

In summary, the power station grounded screen provided in the embodiment of the present disclosure includes grid side grounded screen and power station side joint Earth mat, and therebetween without electrical connection.Therefore, when laying the grid side grounded screen, generally it is convenient to select lay the electricity The position of net side grounded screen, thus preferably the grid side grounded screen can be laid in and other grid side grounded screens on power network In same or like environment, so cause in the grid side grounded screen and power network other each grid side grounded screens have it is identical or Similar resistance to earth, and then the flowing of earth-current on power network is reduced, step-up transformer main transformer winding is flowed through with so as to reduce Property point earth-current, and then alleviate earth-current to power station boost main transformer harm, reached raising power network and generating The effect for the security stood.

Those skilled in the art will readily occur to the disclosure its after considering specification and putting into practice invention disclosed herein Its embodiment.The application is intended to any modification, purposes or the adaptations of the disclosure, these modifications, purposes or Person's adaptations follow the general principle of the disclosure and including the undocumented common knowledges in the art of the disclosure Or conventional techniques.Description and embodiments are considered only as exemplary, and the true scope of the disclosure and spirit are by following Claim is pointed out.

It should be appreciated that the precision architecture that the disclosure is not limited to be described above and is shown in the drawings, and And various modifications and changes can be being carried out without departing from the scope.The scope of the present disclosure is only limited by appended claim.