CN201229831Y

CN201229831Y - Anti-resonance capacitor type voltage mutual transformer

Info

Publication number: CN201229831Y
Application number: CNU2008200295830U
Authority: CN
Inventors: 徐杰; 郭天兴
Original assignee: China XD Electric Co Ltd
Current assignee: China XD Electric Co Ltd
Priority date: 2008-07-09
Filing date: 2008-07-09
Publication date: 2009-04-29
Anticipated expiration: 2018-07-09

Abstract

The utility model relates to a capacitor voltage transformer (CVT for short), which particularly discloses an anti-resonance capacitor voltage transformer. The capacitor voltage transformer comprises an intermediate transformer, and the intermediate transformer comprises iron cores and a primary coil and a secondary coil coiled on the iron cores; the capacitor voltage transformer is characterized in that the iron cores are two C-shaped iron cores which are oppositely arranged, and has two air gaps; the width of the air gap is 1 to 5 millimeters.

Description

A kind of antiresonance capacitance type potential transformer

Technical field

The utility model relates to capacitance type potential transformer (being called for short CVT), relates in particular to a kind of antiresonance capacitance type potential transformer.

Background technology

At present, CVT owing to various superpotential influences, especially in the switching process, is easy to produce the ferro resonance phenomenon in operation of power networks.No matter reason is existing C VT intermediate transformer iron core and is the mountain font or does not ring-likely all have an air gap.The characteristic of the core construction of this transformer, under superpotential effect, generation unshakable in one's determination is saturated, and make CVT easily produce ferro resonance, when resonance condition continued, the overvoltage that is applied on the CVT was very high, is generally 2～3 times of rated voltage, electric current by CVT is also very big, produce very big energy, make the CVT inner heat, cause CVT to damage, even blast, threaten to surrounding devices and personnel.Simultaneously, also can cause the damage of metering of electrical network secondary side and protective device.

In order to prevent that CVT from producing ferro resonance in running, must in the CVT electromagnetic unit, install damper additional and suppress the ferro resonance that overvoltage causes.Damper is to be connected with resistance by fast saturable reactor to constitute, and is bound up on the CVT secondary side residual voltage winding.When in a single day CVT produces ferro resonance, electric current can be very big, and at this moment the rapid degree of depth of damper middling speed saturable reactor is saturated, absorbs energy, as long as the parameter collocation rationally, eliminates the CVT ferro resonance in several cycles, makes CVT recover normal operating condition; But parameter is in case after fixing, be difficult to adjust.

Summary of the invention

The purpose of this utility model is to provide a kind of simple in structure, parameter adjustment antiresonance capacitance type potential transformer easily.

In order to achieve the above object, the technical solution of the utility model is achieved in that a kind of antiresonance capacitance type potential transformer, comprise intermediate transformer, this intermediate transformer contains iron core, and be wound on primary winding and secondary coil on the iron core, it is characterized in that described iron core is opposed two C sections hearts, has two air gaps.

Described air gap is the 1-5 millimeter.

Because intermediate transformer of the present utility model has opposed two C sections hearts, two air gaps that the C sections is formed centrally, directly changed the no-load characteristic of intermediate transformer, no-load current can be controlled in the hundreds of milliampere, improved transformer core saturation point characteristic, increased the intermediate transformer leakage field, it is saturated that transformer core is not easy, and suppresses the generation of ferro resonance; And do not need to install additional damper, make antiresonance capacitance type potential transformer structure simpler.

Description of drawings

Fig. 1 capacitance type potential transformer structural representation;

Fig. 2 tradition intermediate transformer structure chart;

Fig. 3 intermediate transformer structure chart of the present utility model;

Wherein: 1-HV Terminal; 2-high-voltage capacitance; 3-low-voltage capacitance; 4-intermediate voltage terminal; 5-intermediate transformer; 6-earth terminal; 7-lead terminal; N-first low-pressure end; X-second low-pressure end; 8-iron core; 9-inferior coil; 10-secondary coil.

Embodiment

With reference to Fig. 1, high-voltage capacitance 2 and middle piezoelectricity hold 3 and are serially connected in successively between the capacitance type potential transformer high-pressure side 1 and the first low-pressure end N, the intermediate node of high-voltage capacitance 2 and middle piezoelectricity appearance 3 is drawn intermediate voltage terminal 4, is serially connected with 5 windings of intermediate transformer and compensation reactor L between the intermediate voltage terminal 4 and the second low-pressure end X successively.The secondary side of intermediate transformer 5 comprises two secondary winding and residual voltage winding.Lead terminal 7 is provided with secondary side lead end, the first low-pressure end N, the second low-pressure end X of intermediate transformer.Earth terminal 6 well contacts with the earth.

With reference to Fig. 2, traditional intermediate transformer adopts mountain font iron core 8, and secondary coil (low-voltage coil) 10 and primary winding (high-tension coil) 9 are with in center pinch, and secondary coil 10 is at inner ring, and primary winding 9 is in the outer ring.

With reference to Fig. 3, the iron core 8 of intermediate transformer of the present utility model is to adopt opposed two C sections hearts, has small air gap (width 1-5 millimeter) between two C sections hearts, distinguishes coiling primary winding 9 and secondary coil 10 in the heart at two C sections.

Claims

1, a kind of antiresonance capacitance type potential transformer comprises intermediate transformer, and this intermediate transformer contains iron core, and is wound on primary winding and secondary coil on the iron core, it is characterized in that, described iron core is opposed two C sections hearts, has two air gaps.

2, a kind of antiresonance capacitance type potential transformer according to claim 1 is characterized in that, described width of air gap is the 1-5 millimeter.