A kind of equal potential shielded capacitor voltage transformer
Technical field:
The present invention relates to a kind of capacitance type potential transformer, is more particularly to a kind of equal potential shielded capacitor voltage mutual inductance
Device.
Background technology:
AC extra high voltage technology of transmission of electricity in China's is quickly grown in recent years, and this is just carried to the accurate measurement of extra-high voltage grid voltage
High request is gone out.High voltage meter mainly has following three kinds at present:Electromagnetic potential transformer, capacitance type potential transformer
And electronic type voltage transformer.Electromagnetic potential transformer is used for the voltage measurement of below 110kV voltage class, capacitive battery
Pressure transformer is commonly used to the voltage measurement of 110kV aboves.Electronic type voltage transformer is still within researching and developing at present
And experimental stage, need to further it research and solve the problems such as its voltage measurement accuracy, laser life-span, system reliability, at present still
Engineer applied is not put into.
For more than 500kV voltage class, especially for extra-high voltage grade(1000kV), electromagnetic potential transformer by
In insulation difficulty and ferromagnetic resonance easily occurs in primary side and then triggers electric power accident, do not use.Capacitor voltage is mutual
Sensor because its simple in construction, low cost, primary side will not with power network occur ferromagnetic resonance, high reliability, by
It is widely used in the measurement of ultra-high/extra-high voltage voltage class line voltage.
But for the capacitance type potential transformer applied to ultra-high/extra-high voltage field, run into following technical difficulty:It is modern
In network system, digital relay protection system is taken seriously and is used widely more and more, and this just needs electricity
The capacitance type potential transformer for measuring voltage in net has outstanding transient response characteristic, when capacitance type potential transformer primary side
During voltage suddenly change(Short circuit), it is desirable to transformer secondary side voltage should be able to rapidly and accurately reflect the change of primary side voltage
Change.The national standard of capacitance type potential transformer(GB/T4703)Middle regulation, after capacitance type potential transformer primary side short circuit
In 0.2s, secondary side voltage is less than 0.1 to the ratio of secondary side voltage peak before short circuit.Existing capacitance type potential transformer is adopted
By the use of the ferromagnetic resonance damper by energy-storage travelling wave tube as main functional component(Current fast saturable damper is at home
Outer application is wide)Although the type damper has excellent suppression ferro-resonance over-voltage ability, its transient response characteristic
It is universal very poor, it is difficult to meet the requirement that extra-high voltage grid relay protection quick and precisely acts.
The content of the invention:
It is an object of the invention to provide a kind of equal potential shielded capacitor voltage transformer, the capacitance type potential transformer has
Effect improves transient response characteristic.
To achieve the above object, the present invention uses following technical scheme:A kind of equal potential shielded capacitor voltage transformer,
The voltage transformer includes capacitive divider and electromagnetic unit, and the electromagnetic unit includes and the capacitive divider output end
The intermediate transformer that connected compensation reactor and its armature winding are connected with the compensation reactor;The intermediate transformer
Level winding includes main secondary winding and remaining winding;The remaining winding parallel ferromagnetic resonance damper.
A kind of equal potential shielded capacitor voltage transformer provided by the invention, the main circuit of the ferromagnetic resonance damper
Including power electronic devices, control circuit and damped resistor, the power electronic devices makes producing by the control circuit
Turned on during raw ferro-resonance over-voltage, resonant energy is consumed by the damped resistor.
A kind of equal potential shielded capacitor voltage transformer provided by the invention, the electromagnetic unit are interior filled with insulation material
Material, the insulating materials is gas insulating material, foamed insulation material or insulating oil.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, the capacitive divider bag
Include the equivalent potential screen capacitor unit that the pivot flange being provided with by its both ends is connected with each other, the equivalent potential screen capacitor
Unit include being arranged on main capacitor between the upper and lower pivot flange, being sequentially coaxially provided with from inside to outside, interior insulation material,
Annular electrode and insulating sleeve;Set between the annular electrode upper and lower side pivot flange corresponding with its upper and lower side
There is auxiliary capacitor, the auxiliary capacitor is connected by stud and nut with the annular electrode, and the stud is described in
Pivot flange extends corresponding to auxiliary capacitor to its;The stud is provided with spring.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, the stud end face and its
There is certain distance between the corresponding pivot flange, the distance is according at least above the auxiliary capacitor axial expansion amount.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, above and below the main capacitor
The supporting insulator being connected with the pivot flange is respectively equipped with, the supporting insulator is located at the axle center of the insulating sleeve
On;The top and bottom of the insulating sleeve are respectively equipped with the sleeve flange being connected with the pivot flange.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, the main capacitor is with
Voltage capacitance is connected, and the medium voltage both it is introduced to the input of the electromagnetic unit.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, the top of the main capacitor
Portion and bottom are respectively equipped with guide flange, and the inner headed face of the guide flange is arranged on the periphery of the supporting insulator bottom
Outside.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, is arranged on the main capacitance
There is certain down suction between the inner headed face of the guide flange at the top of device and the supporting insulator periphery, the gap
Size is by the guide flange, the relative installation of the supporting insulator and the main capacitor maximum swelling amount Lai really
It is fixed.
Another preferable a kind of equal potential shielded capacitor voltage transformer provided by the invention, it is characterised in that:Institute
The valve rubber for being provided with gap and being affixed with the supporting insulator periphery is stated, the rubber mat thickness is less than the clearance gap
From;
The guide flange inner headed face of the main capacitor bottom and the supporting insulator bottom corresponding thereto
Periphery connected by valve rubber;
Be arranged on the guide flange at the top of the main capacitor by the both sides of its inner headed face with corresponding thereto
The top periphery both sides of the supporting insulator are flexibly connected;
It is arranged on the guide flange and the supports insulative subactivity corresponding thereto of the main capacitor bottom
Connection.
With immediate prior art ratio, the present invention, which provides technical scheme, has following excellent effect
1st, it is special without the energy-storage travelling wave tubes such as inductance, electric capacity, transient response without energy-storage travelling wave tube ferromagnetic resonance damper in the present invention
Property has clear improvement than existing capacitance type potential transformer, before secondary side voltage is lower than short circuit in 0.02 second after primary side short circuit
Less than the 10% of voltage peak, it can meet that ultra-high/extra-high voltage power network modern times relay protection system is rung to capacitance type potential transformer transient state
Answer the strict demand of characteristic;
2nd, electromagnetic unit small volume, in light weight in the present invention;
3rd, electromagnetic unit caloric value is small in the present invention, and stability is high;
4th, it is relatively independent between the main capacitor in the present invention and supporting insulator, not over bolt connection, installation
When can the position of centering capacitor at any time be finely adjusted, avoid the generation of eccentricity issues;
5th, the valve rubber in the present invention serves cushioning effect, ensures that main capacitor will not damage because jolting in transportation
It is bad;
6th, the interstitial structure that is provided with both had met the fixed requirement of main capacitor in the present invention, and can avoid main capacitor due to
Volumetric expansion and damage.
Brief description of the drawings
Fig. 1 is the capacitance type potential transformer circuit diagram of the present invention;
Fig. 2 is the ferromagnetic resonance damper structure schematic diagram of the present invention;
Fig. 3 is that the comparison diagram of the response characteristic of the capacitance type potential transformer of the present invention is intended to;
Fig. 4 is the equivalent potential screen capacitor unit axial section of the present invention;
Wherein, 1- main capacitors, 2- insulating sleeves, 3- auxiliary capacitors, 4- annular electrodes, 5- supporting insulators, 6- branch
Staying is blue;7- sleeve flanges, 8- interior insulation materials, 9- valve rubbers, 10- gaps, 11- guide flanges.
Embodiment
With reference to embodiment, the invention will be described in further detail.
Embodiment 1:
As Figure 1-4, the invention equal potential shielded capacitor voltage transformer of this example includes capacitive divider and electromagnetism
Unit, the electromagnetic unit include the compensation reactor that is connected with the capacitive divider output end and its armature winding with it is described
Intermediate transformer T connected compensation reactor L;The compensation reactor L is in parallel with voltage limiter S, and the intermediate transformer is secondary
Winding includes main secondary first winding 1a1n, main secondary second winding 2a2n, main secondary tertiary winding 3a3n and remaining winding
dadn;The remaining winding dadn Parallel connection ferroresonance dampers Z.
The main circuit of the ferromagnetic resonance damper Z includes IGCT and control circuit D1 and damped resistor D2, described
IGCT makes to turn on when producing ferro-resonance over-voltage by the control circuit, and resonant energy is by the damped resistor D2
Consumption.Filled with insulating materials in the electromagnetic unit, the insulating materials is gas insulating material, foamed insulation material or insulation
Oil.
The equivalent potential screen capacitor that the pivot flange 6 that the capacitive divider includes being provided with by its both ends is connected with each other
Unit, the equivalent potential screen capacitor unit include being arranged between the upper and lower pivot flange 6, from inside to outside sequentially coaxially
Main capacitor 1, interior insulation material 8, annular electrode 4 and the insulating sleeve 2 being provided with;The upper and lower side of annular electrode 4 with and its
Auxiliary capacitor 3 is provided between the corresponding pivot flange 6 of upper and lower side, the auxiliary capacitor 3 passes through stud and nut
It is connected with the annular electrode 4, the pivot flange 6 corresponding to the stud through the auxiliary capacitor 3 to its extends;Institute
State stud and be provided with spring.
Have certain distance between the corresponding pivot flange 6 in the stud end face, the distance according at least above
The axial expansion amount of auxiliary capacitor 3.The spring is in work load state, when the volume of auxiliary capacitor 3 is along axle
To during expansion, the spring below the annular electrode 4 is further compressed, and the amount of spring compression above the annular electrode 4 is reduced,
Otherwise similarly.Compression spring is used both to have ensured that shielding auxiliary capacitor 3 can make shielding with auxiliary again with normal expansion
Help capacitor 3 to be buffered when transport is jolted, avoid damage to annular electrode 4.
The main capacitor is respectively equipped with the supporting insulator 5 being connected with the pivot flange 6 about 1, the support is exhausted
Edge 5 is located on the axle center of the insulating sleeve 2;The top and bottom of the insulating sleeve 2 are respectively equipped with and the supporting methods
The connected sleeve flange 7 of orchid 6.Circular groove is provided with the axis on the top of supporting insulator 5 and bottom, is divided in the groove
Not She You Mume flower contact component, the metal embedded part that two Mume flower contact components pass through through two grooves connects.Described
Insertion metal bar shape electrode in the contact assembly of supporting insulator bottom;The supporting insulator side is corrugated surface.
The main capacitor 1 is connected with middle voltage capacitance C2, and the medium voltage both it is introduced into the electromagnetic unit
Input, medium pressure electric capacity are connected with coupled capacitor device δ.
The top and bottom of the main capacitor 1 are respectively equipped with guide flange 11, and the inner headed face of the guide flange 11 is set
Put outside the periphery of the bottom of supporting insulator 5.
Inner headed face and the supporting insulator 5 for being arranged on the guide flange 11 at the top of main capacitor 1 are cylindrical
There is certain down suction 10 between face, the size in the gap 10 is by the guide flange 11, the relative peace of the supporting insulator 5
Holding position and the maximum swelling amount of the main capacitor 1 determine.
Because in the presence of environment temperature and equipment itself operating temperature, the volume of main capacitor 1 can accordingly become
Change, especially in the axial direction.The structure in the gap 10 had both met the fixed requirement of main capacitor 1, and can avoid main capacitor 1 by
Damaged in volumetric expansion.
The valve rubber 9 being affixed with the periphery of supporting insulator 5 is provided with the gap 10, the valve rubber 9 is thick
Degree is less than the distance of gap 10;The inner headed face of the guide flange 11 of the bottom of main capacitor 1 and institute corresponding thereto
The periphery for stating the bottom of supporting insulator 5 is connected by valve rubber 9;It is arranged on the guiding method at the top of main capacitor 1
Orchid 11 is flexibly connected by the both sides of its inner headed face with the top periphery both sides of the supporting insulator 5 corresponding thereto;
The guide flange 11 for being arranged on the bottom of main capacitor 1 is flexibly connected with the supporting insulator 5 corresponding thereto.
Due to the main capacitor 1 be between supporting insulator 5 it is relatively independent be flexibly connected, fixed not over bolt, thus when master
Capacitor 1 can be finely adjusted in time in the axial direction when there are eccentricity issues, ensure that the smooth installation at the both ends of main capacitor 1 is consolidated
It is fixed.The both ends of main capacitor 1 are fixed by said structure and the supporting insulator 5, main capacitor 1 diametrically can not
It is mobile, it will not topple in transit due to jolting, reach fixed purpose.
The main circuit of the ferromagnetic resonance damper does not include any energy-storage travelling wave tube(Such as inductance, electric capacity), therefore it is described
Ferromagnetic resonance damper Z volumes without energy-storage travelling wave tube are less than the ferromagnetic resonance damper of energy-storage travelling wave tube, and then need bigger electricity
Magnetic cell.In addition, also include the element such as intermediate transformer T, compensation reactor L inside electromagnetic unit, the insulation of each interelement away from
From be also need consider the problem of.Therefore the electromagnetic unit of the present invention also has small volume, in light weight, the advantages that being easy to radiating.
Using the transient response characteristic of the domestic and international existing capacitance type potential transformer of energy-storage travelling wave tube damper and using this
Capacitance type potential transformer of the invention without energy-storage travelling wave tube ferromagnetic resonance damper is compared, and simulation result is shown in Fig. 3.It is real in Fig. 3
Line is actual tested voltage curve, and long dotted line is using the capacitor voltage obtained after the ferromagnetic resonance damper for having energy-storage travelling wave tube
Transformer transient resonse characteristic, short dash line are using the electricity obtained after the ferromagnetic resonance damper of the invention without energy-storage travelling wave tube
Appearance formula voltage transformer transient response characteristic curve.From the figure 3, it may be seen that after capacitance type potential transformer primary side short circuit, at half
In cycle, secondary side voltage is just down to less than 0.1 times of voltage peak before short circuit, effectively improves capacitance type potential transformer
Transient response characteristic.
Finally it should be noted that:The above embodiments are merely illustrative of the technical scheme of the present invention and are not intended to be limiting thereof, to the greatest extent
The present invention is described in detail with reference to above-described embodiment for pipe, those of ordinary skills in the art should understand that:Still may be used
Modified or equivalent substitution with the embodiment to the present invention, and repaiied without departing from any of spirit and scope of the invention
Change or equivalent substitution, it all should cover among present claims scope.