CN201118244Y

CN201118244Y - Chain type static synchronous compensator self excitation start-up circuit

Info

Publication number: CN201118244Y
Application number: CNU2007200642723U
Authority: CN
Inventors: 刘文辉
Original assignee: 刘文辉
Current assignee: TIANJIN XIANDAO BELL ELECTRIC CO., LTD.
Priority date: 2007-08-24
Filing date: 2007-08-24
Publication date: 2008-09-17
Anticipated expiration: 2017-08-24

Abstract

The utility model discloses a self-excitation starting circuit used in a chain-typed static synchronous compensator, belonging to the field of electric automation equipment, which comprises three starting charging current-limiting resistors and a three-phrase contactor; wherein, the three current-limiting resistors are respectively connected with three pairs of contacts of the three-phrase contactor in parallel and then respectively connected in series among three alternating current output points of the chain-typed static synchronous compensator and thee-phrase paralleling switches of the chain-typed static synchronous compensator. The starting circuit of the utility model avoids the high-insulation standing voltage and low local discharge isolation transformer needed by a separate-excitation starting circuit; therefore, the cost of the starting circuit is lower.

Description

A kind of self-excitation start-up circuit of chain static synchronous compensator

Technical field

The utility model relates to a kind of self-excitation start-up circuit of chain static synchronous compensator, belongs to the electric automatization apparatus field.

Background technology

STATCOM (STATCOM or DSTATCOM) is a kind of novel dynamic reactive and harmonic wave compensation arrangement that adopts voltage source inverter to realize, have rapid dynamic response speed, the impact of starting nothing, regulate advantages such as continuous, that floor space is little, and adopt chain inverter (to be called H bridge series inverter, be connected in series by a plurality of H bridge inverter ac output ends and form) STATCOM that realizes have floor space little, need not to insert transformer, low cost and other advantages, be the developing direction of STATCOM.

When realizing the STATCOM of higher alternating voltage output (6kV-35kV) with H bridge series inverter, the starting charging of its H bridge inverter dc bus capacitor becomes difficult, main cause is when by the separate excitation startup power supply electric capacity being charged, the former secondary of isolating transformer wherein need bear very high dielectric voltage withstand, and require that extremely low partial discharge index is arranged, make the isolating transformer cost very high.

Summary of the invention

In order to solve chain static synchronous compensator dc bus capacitor starting charging difficult technologies problem, the utility model provides a kind of self-excitation start-up circuit of chain static synchronous compensator, with needed isolating transformer high dielectric voltage withstand of the start-up circuit of avoiding using always and low partial discharge index, thus the cost of reduction equipment.

The technical scheme that the utility model solves the problems of the technologies described above is: comprise that three start charging current limiter resistance and a three-phase contactor; After described three current-limiting resistances are connected in parallel with three pairs of contacts of described three-phase contactor respectively, are connected on three of chain static synchronous compensator respectively and exchange between the three-phase grid switch of output point and chain static synchronous compensator.

The utility model has the advantages that: chain static synchronous compensator self-excitation start-up circuit is finished the charging to each dc capacitor of chain static synchronous compensator, avoided separate excitation to start the high dielectric voltage withstand that needs and reached low partial discharge transformer, thereby made the start-up circuit cost lower.

Description of drawings

Fig. 1 is the structural representation of the utility model embodiment 1.

Fig. 2 is the structural representation of the utility model embodiment 2.

Embodiment

Referring to Fig. 1,1 is the switch that is incorporated into the power networks among the figure, 2 is start-up circuit, 3 is the chain static synchronous compensator main circuit, the chain static synchronous compensator main circuit comprises that the three-phase chain inverter is connected reactor LA, LB, LC with three, the three-phase chain inverter constitutes star-like wiring with LA, LB, LC series connection back respectively, and KS is the switch that is incorporated into the power networks of chain static synchronous compensator.RA, RB, RC are described three startup charging current limiter resistance among Fig. 1, and JZ is described three-phase contactor.After described three current-limiting resistances are connected in parallel with three pairs of contacts of described three-phase contactor respectively, are connected on three of chain static synchronous compensator respectively and exchange between the three-phase grid K switch S of output point and chain static synchronous compensator.During startup, each device for power switching trigger impulse of chain inverter is in blocking, the contact of JZ is in open position, the K switch that is incorporated into the power networks S closes a floodgate earlier, after this charging to each direct current capacitor is finished by each afterflow power diode of RA, RB, RC and chain inverter in the line voltage source, after direct voltage is established to a certain set point, the closing of contact of contactor JZ, this moment is very little to the impulse current of electrical network, after this controller of chain static synchronous compensator can be removed the pulse blocking, makes device enter controlled running status.The discharge resistance (as RD1) that the balance of each chain link dc capacitor voltage can be by being connected in parallel on each dc capacitor both sides in the charging process and the series circuit of semiconductor switch (as SD1) are finished.

Fig. 2 has provided the another kind enforcement figure of the utility model starting circuit, 1 is the switch that is incorporated into the power networks among the figure, and 2 is start-up circuit, and 4 is the chain static synchronous compensator main circuit, its operation principle is identical with structure shown in Figure 1, and only chain inverter and connection reactor have adopted delta connection.

Any equivalent transformation circuit of doing based on the utility model all belongs to protection range of the present utility model.The utility model also can be used for adopting other converter devices of H bridge series inverter, as active filter, or the like, these application scenarios all belong to protection range of the present utility model.

Claims

1, a kind of self-excitation start-up circuit that is used for chain static synchronous compensator is characterized in that: comprise that three start charging current limiter resistance and a three-phase contactor; After described three current-limiting resistances are connected in parallel with three pairs of contacts of described three-phase contactor respectively, are connected on three of chain static synchronous compensator respectively and exchange between the three-phase grid switch of output point and chain static synchronous compensator.