CN201584892U

CN201584892U - Series connection filter

Info

Publication number: CN201584892U
Application number: CN2009202634152U
Authority: CN
Inventors: 黄克峰; 关胜利
Original assignee: GUANGZHOU CITY GOALAND WATER TECHNOLOGY Co Ltd
Current assignee: Guangzhou Goaland Energy Conservation Tech Co Ltd
Priority date: 2009-11-26
Filing date: 2009-11-26
Publication date: 2010-09-15
Anticipated expiration: 2019-11-26

Abstract

The utility model discloses a series connection filter which is connected between a power supply network and an electric power converter in series; the series connection filter comprises a three-phase reactor and a capacitor. Since the series connection filter is a T-shaped broadband low pass filter formed by the reactor and the capacitor, hardly consume active power and can not produce the influence on electric fundamental power factors and has the suppression effect on the higher harmonic current generated by an electric power converter, therefore the series connection filter can increase the power factor of the whole electricity utilization, reduces the distorted degree of the electric current, has good filtering effect, is particularly suitable for the managing affect of the harmonic pollution of a six-pulse converter; and in addition, the series connection filter belongs to a passive filter, has simple structure and can effectively control the cost.

Description

A kind of series filter

Technical field

The utility model belongs to field of power, particularly a kind of series filter that is used to administer the power converter harmonic pollution.

Background technology

The electric power Semiconductor Converting Technology comprises technology such as the straight unsteady flow of friendship, friendship alternating flow, friendship orthogonal unsteady flow, has a wide range of applications in modern industry.The speed adjusting performance of convertor equipment can satisfy the requirement of various production technology plant equipment, and the energy-saving effect that flow is regulated in the blower fan water pump speed governing is clearly generally accepted by society, is used widely; But the energy-conservation while of convertor equipment also produces a large amount of harmonic waves, has also increased excess loss in the time of energy-conservation, has wasted the part electric energy, also brings harmonic pollution to electrical network, and operation brings influence to motor simultaneously.Harmonic pollution brings extra loss for transmission line and power load.The motor of a common inverter supply, the current distortion rate that flows into electrical network can reach more than 1 00%.According to the loss of transmission line is calculated, do not consider frequency influence, square being directly proportional of the loss of circuit and electric current, transformer loss is directly proportional with electric current, the consideration harmonic effects, the evolution of line loss and frequency is proportional, and frequency is high more, and line loss is high more.

Tradition mainly contains following improvement method for the harmonic wave control of current convertor system:

(1) harmonic wave suppresses reactor.At convertor equipment point of incoming cables series connection inlet wire reactor, this method can make current distortion be suppressed to 35%～45%, and reactor can cause power factor and reduction and influence the convertor equipment power output, generally as supplementary means.

(2) adopt 12 pulses, 18 pulses or high impulse unsteady flow more.This method can drop to 5%～10% with current distortion, but the cost height relies on convertor equipment itself, is suitable for newly-built high volume item.

(3) LC filter.Convertor equipment point of incoming cables LC fixed filters in parallel, this method both can play the filtering effect to the harmonic current that convertor equipment produces; The effect that can play compensating power again, improves power factor.The harmonic filtration rate does not wait 30%～80%, and compensating power when shortcoming is a) filtering is walked out of when showing when reactive power is different with harmonic current, and filter effect is poor; B) effective to the harmonic filtration of Design of Filter tuned frequency annex, poor to other times harmonic filtration results; C) the LC filter may cause harmonic wave to amplify, even causes system resonance.

(4) active filter.This method can drop to current distortion below 5%, but filter effect depends on accuracy of detection, the cost height.Active filter begins research and development abroad at the beginning of the seventies in last century, and is succeeded in developing by US Westinghouse company in 1976.Active filter is very good, but active filter cost height, its inner a large amount of electronic components that use, poor reliability, maintenance is big, and itself is consumed power again, in practical application seldom.

The utility model content

For addressing the above problem, the utility model provides a kind of good wave filtering effect, series filter that cost is low.

The utility model is that the technical scheme that its problem of solution is adopted is:

A kind of series filter, this series filter comprises three-phase reactor and capacitor, described three-phase reactor comprises first reactor, second reactor and the 3rd reactor, described capacitor comprises first capacitor, second capacitor and the 3rd capacitor, the end of incoming cables of described first reactor is used for being connected with power supply grid, leading-out terminal is connected with the end of incoming cables of described second reactor, the leading-out terminal of second reactor is used for being connected with power converter, the 3rd reactor and first capacitor, second capacitor, the 3rd capacitor is formed tuned filter and is attempted by between first reactor and second reactor.

The beneficial effects of the utility model are: the utility model is the T molded breadth low-pass filter that is made of reactor and capacitor, consume active power hardly and can the phasor power factor of electricity consumption not exerted an influence, and it can all have the inhibition effect to the higher harmonic current that power converter produces, therefore can improve the power factor of whole electricity consumption, reduce the degree of current distortion, have good filtering effect, be specially adapted to the improvement aspect of six pulse converter harmonic pollutions; In addition, because the utility model belongs to passive filter, it is simple in structure, and cost can be effectively controlled.

Description of drawings

The utility model is described in further detail below in conjunction with drawings and Examples:

Fig. 1 is the schematic diagram of first kind of mode of connection of the utility model;

Fig. 2 is the schematic diagram of second kind of mode of connection of the utility model;

Fig. 3 is the schematic diagram of the third mode of connection of the utility model;

Fig. 4 is a use winding diagram of the present utility model.

Embodiment

Referring to figs. 1 through Fig. 4, series filter of the present utility model is serially connected with between power supply grid and the power converter, be used for the improvement of power converter harmonic pollution, this series filter comprises three-phase reactor and capacitor, three-phase reactor comprises the first reactor L1, the second reactor L2 and the 3rd reactor L3, capacitor comprises the first capacitor C1, the second capacitor C2 and the 3rd capacitor C3, the end of incoming cables of the first reactor L1 is used for being connected with power supply grid, leading-out terminal is connected with the end of incoming cables of the described second reactor L2, the leading-out terminal of the second reactor L2 is used for being connected with power converter, the 3rd reactor L3 and the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 forms tuned filter and is attempted by between the first reactor L1 and the second reactor L2.Series filter is whole to become T type structure, and by choosing suitable three-phase reactor, capacitor parameters, filter neither sends reactive power when can be implemented in nominal operation, and absorbing reactive power does not impact power supply grid yet.

When practical application, the impedance sum of the first reactor L1, the second reactor L2 take the electric loading impedance 5～25% between, filter effect according to actual needs and deciding; The 3rd reactor L3 and the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 form the tuned filter of the feature number of times 5 times of six pulse power converters, the capacity of the capacity of filter and the first reactor L1, the second reactor L2 is suitable, make tuned filter neither export reactive power, also do not send reactive power.

Fig. 1 is the diagram of first kind of mode of connection of the present utility model, wherein the end of incoming cables of the 3rd reactor L3 is connected with the leading-out terminal of the first reactor L1, the leading-out terminal of the 3rd reactor is connected to the end of the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 respectively, the other end of the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 connects together, and promptly the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 adopt star connection to interconnect.

Fig. 2 is the diagram of second kind of mode of connection of the present utility model, wherein the end of incoming cables of the 3rd reactor L3 is connected with the leading-out terminal of the first reactor L1, the leading-out terminal of the 3rd reactor is connected to the end of the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 respectively, and the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 adopt delta connection to interconnect.

Fig. 3 is the diagram of the third mode of connection of the present utility model, wherein the end of incoming cables of the 3rd reactor L3 is connected with the leading-out terminal of the first reactor L1, the leading-out terminal of the 3rd reactor is connected to the end of the first capacitor C1, the second capacitor C2, the 3rd capacitor C3 respectively, and the three-phase of the 3rd reactor L3 is connected back formation respectively with capacitor three-phase branch road adopts delta connection to interconnect.

Above-mentioned several mode of connection has difference, but the high order harmonic component that power converter produces is all had good regulation effect, and experiment shows, adopts that the current distortion in the circuit can drop to about 5%～10% behind the series filter of the present utility model.

In addition, the first reactor L1 in the utility model, the second reactor L2 can lump together and make a double winding reactor, perhaps the first reactor L1, the second reactor L2, the 3rd reactor L3 lump together and make winding reactor more than, make the cost of integral manufacturing reactor to reduce, and can reduce the volume size of series filter greatly, thereby reach better result of use.

Certainly, the invention is not limited to above-mentioned execution mode, those of ordinary skill in the art also can make all equivalent variations or replacement under the prerequisite of the utility model spirit, modification that these are equal to or replacement all are included in the application's claim institute restricted portion.

Claims

1. series filter, it is characterized in that: this series filter comprises three-phase reactor and capacitor, described three-phase reactor comprises first reactor (L1), second reactor (L2) and the 3rd reactor (L3), described capacitor comprises first capacitor (C1), second capacitor (C2) and the 3rd capacitor (C3), the end of incoming cables of described first reactor (L1) is used for being connected with power supply grid, leading-out terminal is connected with the end of incoming cables of described second reactor (L2), the leading-out terminal of second reactor (L2) is used for being connected with power converter, the 3rd reactor (L3) and first capacitor (C1), second capacitor (C2), the 3rd capacitor (C3) is formed tuned filter and is attempted by between first reactor (L1) and second reactor (L2).

2. a kind of series filter according to claim 1, the end of incoming cables that it is characterized in that described the 3rd reactor (L3) is connected with the leading-out terminal of first reactor (L1), the leading-out terminal of the 3rd reactor is connected to an end of first capacitor (C1), second capacitor (C2), the 3rd capacitor (C3) respectively, and the other end of first capacitor (C1), second capacitor (C2), the 3rd capacitor (C3) connects together.

3. a kind of series filter according to claim 1, the end of incoming cables that it is characterized in that described the 3rd reactor (L3) is connected with the leading-out terminal of first reactor (L1), the leading-out terminal of the 3rd reactor is connected to an end of first capacitor (C1), second capacitor (C2), the 3rd capacitor (C3) respectively, and first capacitor (C1), second capacitor (C2), the 3rd capacitor (C3) adopt delta connection to interconnect.

4. a kind of series filter according to claim 1, the end of incoming cables that it is characterized in that described the 3rd reactor (L3) is connected with the leading-out terminal of first reactor (L1), the leading-out terminal of the 3rd reactor is connected to an end of first capacitor (C1), second capacitor (C2), the 3rd capacitor (C3) respectively, and the three-phase of described the 3rd reactor (L3) is connected back formation respectively with capacitor three-phase branch road adopts delta connection to interconnect.