CN204794112U - Reactive power compensator - Google Patents

Abstract

The utility model discloses a reactive power compensator, it includes shunt capacitance ware group, the 2nd shunt capacitance ware group, a discharge coil, the 2nd discharge coil, the bypass switch, shove restriction reactor and quadrupole ground connection isolator, after establishing ties, shunt capacitance ware group and the 2nd shunt capacitance ware group be connected with the electric power system generating line through high voltage circuit breaker, a discharge coil and the parallel connection of shunt capacitance ware group, the 2nd discharge coil and the parallel connection of the 2nd shunt capacitance ware group, with the 2nd shunt capacitance ware parallel connection of group after the bypass switch establishes ties with the restriction reactor that shoves, tripolar among the quadrupole ground connection isolator is connected with the inlet wire side that a shunt capacitance ware was organized, and another utmost point among the quadrupole ground connection isolator is connected with the neutral point that the 2nd shunt capacitance ware was organized. The utility model discloses a control the bypass switch can realize organizing the reactive compensation capacity of the adjustment of output capacity, alright two grades of output to the shunt capacitance ware.

Description

A kind of reactive power compensator

Technical field

The utility model relates to a kind of reactive power compensator, belongs to power system reactive power control technology field.

Background technology

The many employings of reactive power compensation of current electric power system arrange compensation capacitors to realize at substation low-voltage side, because the load of electric power system has fluctuation in time, also present fluctuation change to idle demand.In current transformer station, reactive-load compensation capacitor allocation plan is low capacity, divides into groups more, when load fluctuation causes the reactive requirement change of electric power system, drops into by group or exit reactive-load compensation capacitor device according to reactive requirement.This allocation plan is the major programme of the idle configuration of current transformer station, but, there is following weak point in actual motion:

(1) capacitor grouping is many, need more switch cubicle and other relevant devices, especially 220kV substation low-voltage side reactive power compensator can reach group more than 20, need 20 multiaspect low-tension switch cabinets and supporting secondary device, cable, series reactance apparatus, equipment investment is very large, and installation, maintenance workload also increase thereupon;

(2) a large amount of reactive-load compensation capacitors takies very large space, especially for the capacitor of necessary indoor layout, needs very large construction area, occupies valuable land resource, also improve the construction cost of transformer station.

(3) for meeting load fluctuation to idle demand, the capacitor switching of low capacity, many groupings needs operation multiple stage circuit breaker to realize, complicated operation; In addition, breaker operator is frequent, more easily causes equipment fault, is a very large hidden danger to the safe and reliable operation of electrical network.

Utility model content

For overcoming the deficiency that above-mentioned prior art exists, the utility model provides a kind of reactive power compensator, and it can solve in current reactive power compensator, and capacitor grouping is many, space large and the problem of complicated operation.

The technical scheme in the invention for solving the technical problem is: a kind of reactive power compensator, it is characterized in that, comprise the first Shunt Capacitor Unit, second Shunt Capacitor Unit, first discharge coil, second discharge coil, by-pass switch, inrush current limiting reactor and four pole earthing isolators, described first Shunt Capacitor Unit is connected with electrical system bus by primary cut-out with after the second Shunt Capacitor Unit series connection, described first discharge coil and the first Shunt Capacitor Unit are connected in parallel, described second discharge coil and the second Shunt Capacitor Unit are connected in parallel, be connected in parallel with the second Shunt Capacitor Unit after described by-pass switch and the series connection of inrush current limiting reactor, three poles in described four pole earthing isolators are connected with the inlet wire side of the first Shunt Capacitor Unit, another pole in four pole earthing isolators is connected with the neutral point of the second Shunt Capacitor Unit.

Further, this reactive power compensator also comprises series reactor, and described series reactor is arranged between primary cut-out and the first discharge coil.

Further, this reactive power compensator also comprises metal oxide arrester, and described metal oxide arrester is connected with the inlet wire side of the first Shunt Capacitor Unit.

Preferably, described by-pass switch comprises vacuum circuit-breaker.

Preferably, described first Shunt Capacitor Unit comprises N1 group first series capacitor bank be connected in parallel, and each is organized the first series capacitor bank and comprises M1 the capacitor be connected in series; Described second Shunt Capacitor Unit comprises N2 group second series capacitor bank be connected in parallel, and each is organized the second series capacitor bank and comprises M2 the capacitor be connected in series; N1, N2, M1, M2 are the integer being more than or equal to 2.

Preferably, when the capacitance of the first Shunt Capacitor Unit and the capacitance of the second Shunt Capacitor Unit unequal time, reactive power compensator has two-stage reactive capability output level.

Preferably, when the capacitance of the first Shunt Capacitor Unit is equal with the capacitance of the second Shunt Capacitor Unit, the high power capacity value that reactive power compensator exports is 2 times of low capacity value, has lift face amount, half capacity two-stage reactive capability output level.

The beneficial effects of the utility model are as follows:

Reactive power compensator of the present utility model is made up of two Shunt Capacitor Unit, the inrush current limiting reactor of the by-pass switch for bypass in parallel of the Shunt Capacitor Unit near neutral point and restriction folding moment transient process, when the bypass switch is opened, two Shunt Capacitor Unit series connection access buses, whole loop capacitor value is large, thus, this reactive power compensator exports lower reactive capability; Otherwise, when by-pass switch closes, only there is a Shunt Capacitor Unit access bus, it is low when capacitive reactance is comparatively connected, thus, this reactive power compensator exports high reactive compensation capacity, like this, the adjustment that the utility model can realize Shunt Capacitor Unit output capacity by controlling by-pass switch, the reactive compensation capacity of this reactive power compensator just exportable two grades.

The utility model solves the many problems of current capacitor group capacity, propose a kind of two-stage capacity reactive compensation Shunt Capacitor Unit device, there is the reactive compensation capacity of two grades, large compensation capacity or little compensation capacity can be selected according to the needs compensated, achieve 1 Capacitor banks and export the idle function of 2 kinds of different capabilities, thus decrease the number of packet of reactive power compensation, decrease equipment investment and transformer station's floor space.The utility model is without the need to breaker operator in addition, just can realize the switching of condenser capacity by means of only folding by-pass switch, simple to operate, safe and reliable.

These two grounding apparatuss of single-phase earthing isolating switch of three-phase ground isolating switch and neutral point side are merged into four pole earthing isolator equipment by the utility model, save device fabrication resource, substantially increase the convenience of the daily tour of operations staff and maintenance, reduce operating cost.

Accompanying drawing explanation

Below in conjunction with accompanying drawing, the utility model is further illustrated:

Fig. 1 is structural representation of the present utility model;

In figure, CB1 is the first Shunt Capacitor Unit, CB2 is the second Shunt Capacitor Unit, L1 is the first discharge coil, L2 is the second discharge coil, KM is vacuum contactor, L3 is inrush current limiting reactor, QE is four pole earthing isolators, QF is primary cut-out, BUS is electrical system bus, L is series reactor, FV is metal oxide arrester.

Embodiment

For clearly demonstrating the technical characterstic of this programme, below by embodiment, and in conjunction with its accompanying drawing, the utility model is elaborated.Disclosing hereafter provides many different embodiments or example is used for realizing different structure of the present utility model.Of the present utility model open in order to simplify, hereinafter the parts of specific examples and setting are described.In addition, the utility model can in different example repeat reference numerals and/or letter.This repetition is to simplify and clearly object, itself does not indicate the relation between discussed various embodiment and/or setting.It should be noted that parts illustrated in the accompanying drawings are not necessarily drawn in proportion.The utility model eliminates the description of known assemblies and treatment technology and process to avoid unnecessarily limiting the utility model.

As shown in Figure 1, a kind of reactive power compensator of the present utility model, it comprises the first Shunt Capacitor Unit, second Shunt Capacitor Unit, first discharge coil, second discharge coil, vacuum circuit-breaker, inrush current limiting reactor, four pole earthing isolators, series reactor and metal oxide arrester, described first Shunt Capacitor Unit is connected with electrical system bus by primary cut-out with after the second Shunt Capacitor Unit series connection, described first discharge coil and the first Shunt Capacitor Unit are connected in parallel, described second discharge coil and the second Shunt Capacitor Unit are connected in parallel, be connected in parallel with the second Shunt Capacitor Unit after described vacuum circuit-breaker and the series connection of inrush current limiting reactor, three poles in described four pole earthing isolators are connected with the inlet wire side of the first Shunt Capacitor Unit, another pole in four pole earthing isolators is connected with the neutral point of the second Shunt Capacitor Unit, described series reactor is arranged between primary cut-out and the first discharge coil, described metal oxide arrester is connected with the inlet wire side of the first Shunt Capacitor Unit.

Described first Shunt Capacitor Unit comprises N1 group first series capacitor bank be connected in parallel, and each is organized the first series capacitor bank and comprises M1 the capacitor be connected in series; Described second Shunt Capacitor Unit comprises N2 group second series capacitor bank be connected in parallel, and each is organized the second series capacitor bank and comprises M2 the capacitor be connected in series; N1, N2, M1, M2 are the integer being more than or equal to 2.Be convenient to the capacitance of adjustment first Shunt Capacitor Unit and the second Shunt Capacitor Unit like this.

When the capacitance of the first Shunt Capacitor Unit and the capacitance of the second Shunt Capacitor Unit unequal time, reactive power compensator has two-stage reactive capability output level.

When the capacitance of the first Shunt Capacitor Unit is equal with the capacitance of the second Shunt Capacitor Unit, the high power capacity value that reactive power compensator exports is 2 times of low capacity value, has lift face amount, half capacity two-stage reactive capability output level.

Below operation principle of the present utility model and parameter thereof are described in detail.

One, the principle analysis of reactive power compensator

If power system voltage is U, if ignore the capacitive rise effect of series reactor, then think that the first Shunt Capacitor Unit CB1 is identical with power system voltage with the series voltage of the second Shunt Capacitor Unit CB2, if system angle frequency is ω, the capacitance of the first Shunt Capacitor Unit CB1, the second Shunt Capacitor Unit CB2 is respectively C ₁, C ₂;

(1) when vacuum circuit-breaker KM disconnects:

First Shunt Capacitor Unit CB1, the second Shunt Capacitor Unit CB2 series connection connecting system, capacitive reactance total after series connection:

${\mathrm{Xc}}_1=\frac{1}{w}\·\frac{C_1+C_2}{C_1{C}_2}---\left(1\right)$

The reactive capability that now reactive power compensator exports is:

${\mathrm{Sc}}_1=\frac{U^2}{{\mathrm{Xc}}_1}=\frac{U^2\·w}{\frac{1}{c_1}+\frac{1}{c_2}}---\left(2\right)$

(2) when vacuum circuit-breaker KM closes:

Second Shunt Capacitor Unit CB2 is bypassed, and only has the first Shunt Capacitor Unit CB1 to access loop, and the reactive capability that now reactive power compensator exports is:

${\mathrm{Sc}}_2=\frac{U^2}{{\mathrm{Xc}}_2}=U^2{\mathrm{wc}}_1=\frac{U^2\·w}{\frac{1}{c_1}}---\left(3\right)$

(3) being changed to of reactive power compensator input capacity before and after vacuum circuit-breaker folding is compared:

$\mathrm{\Δ}Sc={\mathrm{Sc}}_2-{\mathrm{Sc}}_1=\frac{U^2{{\mathrm{wc}}_1}^2}{c_1+c_2}=\frac{U^2{\mathrm{wc}}_1}{1+\frac{c_2}{c_1}}---\left(4\right)$

Drawn by formula (3) and formula (4), before and after vacuum circuit-breaker is closed, the ratio of the second Shunt Capacitor Unit CB2 and the capacitance of the first Shunt Capacitor Unit CB1 is depended in the change of capacity of reactive power compensation device, that is: when close vacuum circuit-breaker KM time reactive power compensator export high level reactive power Sc ₂, when disconnecting vacuum circuit-breaker KM, reactive power compensator exports low value reactive power Sc ₁;

When the capacitance of the first Shunt Capacitor Unit is equal with the capacitance of the second Shunt Capacitor Unit,

namely this reactive power compensator has lift face amount, half capacity two-stage reactive capability output level.

Two, the device parameter of reactive power compensator calculates

The calculation of parameter of (1) first Shunt Capacitor Unit CB1

If the low value reactive power that reactive power compensator exports is Sc ₁, the high level reactive power that reactive power compensator exports is Sc ₂, power system voltage is U, and when vacuum circuit-breaker closes, the voltage on the first Shunt Capacitor Unit CB1 is power system voltage, and reactive power compensator output reactive power is Sc ₂, then the capacitance of the first Shunt Capacitor Unit CB1 is:

$C_1=\frac{1}{w\·{\mathrm{Xc}}_2}=\frac{1}{w}\frac{{\mathrm{Sc}}_2}{U^2}---\left(5\right)$

Therefore the rated voltage of the first Shunt Capacitor Unit CB1 is U, capacitance C ₁for rated capacity is Sc ₂;

The calculation of parameter of (2) second Shunt Capacitor Unit CB2

When vacuum circuit-breaker disconnects, the first Shunt Capacitor Unit CB1 connects with the second Shunt Capacitor Unit CB2, and now reactive power compensator exports low value reactive power Sc ₁if the voltage now on the first Shunt Capacitor Unit CB1 is U ₁, voltage on the second Shunt Capacitor Unit CB2 is U ₂, then:

${\mathrm{Sc}}_1={\mathrm{wC}}_1{U}_1^2+{\mathrm{wC}}_2{U}_2^2---\left(6\right)$

Again according to Kirchoff s voltage, current law, there is following relation for whole circuit:

U＝U ₁+U ₂(7)

wC ₁U ₁＝wC ₁U ₂(8)

Simultaneous formula (6), formula (7) and formula (8), solution:

$C_2=\frac{C_1{\mathrm{Sc}}_1}{U^2{\mathrm{wc}}_1-{\mathrm{sc}}_1}---\left(9\right)$

$U_1=\frac{{\mathrm{Sc}}_1}{{\mathrm{Uwc}}_1}---\left(10\right)$

$U_2=U-\frac{{\mathrm{Sc}}_1}{{\mathrm{Uwc}}_1}---\left(11\right)$

Bring formula (5) into formula (9) respectively and formula (11) can obtain:

$C_2=\frac{{\mathrm{Sc}}_1{\mathrm{Sc}}_2}{U^{2}w({\mathrm{Sc}}_2-{\mathrm{Sc}}_1)}=C_1\frac{{\mathrm{Sc}}_1}{{\mathrm{Sc}}_2-{\mathrm{Sc}}_1}---\left(12\right)$

$U_2=\frac{U({\mathrm{Sc}}_2-{\mathrm{Sc}}_1)}{{\mathrm{Sc}}_2}---\left(13\right)$

Therefore the rated voltage of the second Shunt Capacitor Unit CB2 is capacitance C ₂for rated capacity is

(3) calculation of parameter of vacuum circuit-breaker KM

Neutral point connection function is only served as when vacuum circuit-breaker KM closes, pass through without operating current, its continuous firing electric current is only the unsymmetrical current of the first Shunt Capacitor Unit, the unsymmetrical current of general first Shunt Capacitor Unit is very low, and the continuous firing electric current of vacuum circuit-breaker KM can be considered by 10% of Shunt Capacitor Unit rated current; Vacuum circuit-breaker is attempted by the second Shunt Capacitor Unit CB2, therefore rated voltage is identical with the rated voltage of the second Shunt Capacitor Unit CB2, and namely the rated voltage of vacuum circuit-breaker KM is $\frac{U({\mathrm{Sc}}_2-{\mathrm{Sc}}_1)}{{\mathrm{Sc}}_2}.$

The utility model just can export two kinds of capacity by a set of capacitor device, thus decreases the number of packet of reactive power compensation.For 10kV reactive power compensation, the capacitor of 3.6Mvar and 4.8Mvar two kinds of group capacities is configured if need in the usual way, need two cover switch cubicles and series reactor, earthed switch, lightning arrester equipment simultaneously, and the utility model only needs the operation by vacuum circuit-breaker, just one group of exportable 3.6Mvar and 4.8Mvar reactive compensation capacity of equipment be can realize, equipment investment and transformer station's floor space decreased.

When usual manner configures the complete reactive power compensation of 2 groups of different capabilities, when needing switch capacitor group, need first to disconnect Capacitor banks 1 switch, then drop into Capacitor banks 2 switch, operating process is complicated, needs increased operating frequency circuit breaker also may cause equipment fault when load fluctuation is violent.The utility model achieves without the need to breaker operator, just can realize the switching of condenser capacity by means of only folding vacuum circuit-breaker, simple to operate, safe and reliable.

The utility model is that Shunt Capacitor Unit installs one group of four pole earthing isolator, namely original three-phase ground isolating switch is added single-phase earthing isolating switch and directly merge into four pole earthing isolators, three poles in described four pole earthing isolators are connected with described Shunt Capacitor Unit inlet wire side, and another pole is connected with described Shunt Capacitor Unit neutral point.Because four pole earthing isolators only have an operating mechanism, when it is operative, four pole synchronization actions of earthing isolator, make the inlet wire side of Capacitor banks and neutral point side realize the operation of synchronous ground connection.Adopt an operating mechanism to complete the reliable ground of Capacitor banks, ensure that the reliability of Capacitor banks ground connection, improve fail safe and the convenience of overhaul of the equipments.

The above is preferred implementation of the present utility model; for those skilled in the art; under the prerequisite not departing from the utility model principle, can also make some improvements and modifications, these improvements and modifications are also regarded as protection range of the present utility model.

Claims (7)

1. a reactive power compensator, it is characterized in that, comprise the first Shunt Capacitor Unit, second Shunt Capacitor Unit, first discharge coil, second discharge coil, by-pass switch, inrush current limiting reactor and four pole earthing isolators, described first Shunt Capacitor Unit is connected with electrical system bus by primary cut-out with after the second Shunt Capacitor Unit series connection, described first discharge coil and the first Shunt Capacitor Unit are connected in parallel, described second discharge coil and the second Shunt Capacitor Unit are connected in parallel, be connected in parallel with the second Shunt Capacitor Unit after described by-pass switch and the series connection of inrush current limiting reactor, three poles in described four pole earthing isolators are connected with the inlet wire side of the first Shunt Capacitor Unit, another pole in four pole earthing isolators is connected with the neutral point of the second Shunt Capacitor Unit.

2. a kind of reactive power compensator according to claim 1, is characterized in that, also comprise series reactor, and described series reactor is arranged between primary cut-out and the first discharge coil.

3. a kind of reactive power compensator according to claim 1, is characterized in that, also comprise metal oxide arrester, and described metal oxide arrester is connected with the inlet wire side of the first Shunt Capacitor Unit.

4. a kind of reactive power compensator according to any one of claims 1 to 3, is characterized in that, described by-pass switch comprises vacuum circuit-breaker.

5. a kind of reactive power compensator according to any one of claims 1 to 3, is characterized in that, described first Shunt Capacitor Unit comprises N1 group first series capacitor bank be connected in parallel, and each is organized the first series capacitor bank and comprises M1 the capacitor be connected in series; Described second Shunt Capacitor Unit comprises N2 group second series capacitor bank be connected in parallel, and each is organized the second series capacitor bank and comprises M2 the capacitor be connected in series; N1, N2, M1, M2 are the integer being more than or equal to 2.

6. a kind of reactive power compensator according to claim 5, is characterized in that, when the capacitance of the first Shunt Capacitor Unit and the capacitance of the second Shunt Capacitor Unit unequal time, reactive power compensator has two-stage reactive capability output level.

7. a kind of reactive power compensator according to claim 5, it is characterized in that, when the capacitance of the first Shunt Capacitor Unit is equal with the capacitance of the second Shunt Capacitor Unit, the high power capacity value that reactive power compensator exports is 2 times of low capacity value, has lift face amount, half capacity two-stage reactive capability output level.