CN201374562Y

CN201374562Y - Dynamic electric power filtering compensation device

Info

Publication number: CN201374562Y
Application number: CN200920142941U
Authority: CN
Inventors: 王正斌
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-01-21
Filing date: 2009-01-21
Publication date: 2009-12-30
Anticipated expiration: 2019-01-21

Abstract

The utility model relates to a dynamic electric power filtering compensation device, comprising a main circuit and a control circuit, wherein the main circuit comprises a power filtering device (FC) mounted on a transformer station high-tension bus bar, a thyristor switching reactor (TSR) mounted on the rectifier transformer low-tension bus bar and formed by inverse parallel of thyristors of same specification and then series connection with an inductor and a thyristor control reactor (TCR); the control circuit comprises a voltage sampling device and a current sampling device on the transformer station high-tension bus, a controller for processing the sampling signal, a trigger for sending the control signal from the controller to the thyristor reactor. The dynamic electric powder filtering compensation device has features of simpleness, credibility, continuous adjustable reactive power, power factor near to 1, low cost and safety.

Description

A kind of dynamic power filtering compensation device

Technical field

The utility model relates to harmonic and dynamic reactive power compensation equipment in the AC electric power systems.

Background technology

The industrial load of incoming transport electric power system, especially steel rolling mill or have the factory of similar load character, its DC transmission device is to adopt six phase or ten two-phase convertor assemblys, convertor assembly produces (6k+1) or (12k+1) subharmonic in process of production, harmonic wave produces electric power system and pollutes, and forms the harmonic wave public hazards.The convertor assembly low power factor needs compensating power simultaneously.In order to solve the problem of steel rolling mill's harmonic pollution and reactive power compensation, at present domestic generally adopt be:

1, power filter device FC, i.e. FC scheme are installed on steel rolling mill's department substation high voltage bus.The FC scheme is to constitute resonant tank by reactor L and capacitor C series connection, to the characteristic harmonics number of times (as: 5 times, 7 times, 11 subharmonic etc.) form impedance path, arrive the purpose of filtering, the capacitor first-harmonic provides reactive power for electric power system simultaneously, carries out reactive power compensation and improves power factor.The shortcoming of this power filter device FC is: FC is according to certain electric power system parameter and certain load parameter design and installation.Because the capacity of power filter device FC is fixed, and is subjected to capacitor impulse electricity time restriction, so can not be according to load variations quick adjustment reactive power.Therefore, when milling train is not worked, will produce reactive power and send problem, thereby cause power factor to cross low and impose a fine.Reactive power is sent the generation loss.

2, Static Type Dynamic Reactive Compensation Device (SVC), i.e. FC+TCR scheme are installed.The L-C series filter of the K subharmonic that constitutes by inductance and electric capacity and form by switched inductors and electronic control circuit that the thyristor inverse parallel of same size constitutes.Industrial load is common rolling mill or arc furnace, and this nonlinear-load can produce a large amount of harmonic waves in process of production, and harmonic wave produces supplementary load loss in electric equipments such as circuit, transformer, forms the harmonic wave public hazards.The shortcoming that this Static Type Dynamic Reactive Compensation Device SVC is installed is: the control system complexity, thyristor is wanted series and parallel, in case certain thyristor in the thyristor string is breakdown, all system voltage just is added on other several the thyristors, causes other thyristor puncture and causes that the thyristor string punctures; TCR among the SVC is a big harmonic source, the harmonic pollution electric power system of generation; In addition, Static Type Dynamic Reactive Compensation Device (SVC) being installed costs an arm and a leg.

3, the reactive power compensator of aontactless switch of Chinese patent specification: CN99109784.X description is the FC+TSR scheme.The L-C series filter of the K subharmonic that this device is made of inductance and electric capacity and be made up of switched inductors and electronic control circuit that the thyristor inverse parallel of same size constitutes, filter and switched inductors be in parallel to insert same bus.This patent is applicable to that the serious or load of supply power voltage wave distortion contains and enriches harmonic wave such as single-phase welding machine group, and electricity-saving lamp group occasion can be used 10KV or more in the voltage levels electric power system.This patent can have extremely fast compensating power, improves power factor; The thyristor inverse parallel constitutes switched inductors (TSR), thyristor or full conducting, or contract fully, and current waveform is sinusoidal wave, therefore, self does not produce harmonic wave.Its shortcoming is: when it is used for 10KV and above electric power system thereof, (SVC) is the same with Static Type Dynamic Reactive Compensation Device, thyristor is wanted series and parallel, in case certain thyristor in the thyristor string is breakdown, all system voltage just is added on other several the thyristors, causes other thyristor puncture and causes that the thyristor string punctures; Because the switched inductors (TSR) that the thyristor inverse parallel constitutes has the utmost point for the reactive power that system provides, when loading than minor swing, reactive power compensation is difficult to select, can cause switched inductors to throw owes to mend, excision is crossed the phenomenon of mending again and is taken place, and can not provide continuously adjustable reactive power for electric power system; In addition, this technical scheme can cause this increase when being applied to 10KV and above electric power system thereof, implements and has certain degree of difficulty.

Summary of the invention

The purpose of this utility model is exactly in order to overcome the above problems, and a kind of dynamic power filtering compensation device is provided, and carrying out the compensation of harmonic and fast reactive, this apparatus control system is simple and reliable, reactive power is adjustable continuously, power factor is near 1, and cost is low.

The technical solution of the utility model is design like this: a kind of dynamic power filtering compensation device, be characterized in: it is made up of main circuit and control circuit, its main circuit comprises the power filter device (FC) that is installed on transformer station's high voltage bus, be installed in the rectification step-down press on the bus by thuristor throw-in and throw-off reactor (TSR) that is composed in series with inductance after the thyristor inverse parallel of same size and thyristor-controlled reactor (TCR); The control signal that its control circuit comprises the controller handled from the voltage sampling apparatus of transformer station's high voltage bus up-sampling and current sampling device, with sampled signal, send controller is delivered to the trigger of thyristor reactor.

Because the utility model has been installed electric power passive filtration unit FC on transformer station's high voltage bus, the capacitive reactive power of appointment can be provided for system, improved power factor and eliminated the harmonic wave public hazards.Thuristor throw-in and throw-off control reactor TSR+TCR, be installed in the low-pressure side of rectifier transformer, it is to be finished jointly by thuristor throw-in and throw-off reactor TSR and two devices of thyristor-controlled reactor TCR that the idle device of perception is provided, full conducting when the characteristics of thuristor throw-in and throw-off reactor TSR are its thyristor input reactor, complete shut-down is disconnected during the excision reactor, thuristor throw-in and throw-off reactor TSR current waveform is sinusoidal wave, so itself does not produce harmonic wave, thyristor-controlled reactor TCR provides continuously adjustable idle for electric power system, because thyristor-controlled reactor TCR capacity is less, only produces a spot of harmonic wave.Thyristor as the switching control switch does not need connection in series-parallel, and main circuit is simple, and cost is low.Because thyristor does not need connection in series-parallel; so thyristor does not need all to press the current-sharing protective circuit; trigger does not need optical fiber to isolate (adopting pulse transformer to isolate) yet, is the simple and reliable practicality of control core device and trigger with the single-chip microcomputer, can adopt CPU80C196 chip or other processor.

Description of drawings

Fig. 1 is the utility model circuit theory diagrams.

Among the figure 1, current sampling device 2, voltage sampling apparatus 3, transformer station's high voltage bus 4, power filter device (FC) 5, rectifier transformer 6, low-pressure side bus 7, thyristor reactor 8, thuristor throw-in and throw-off reactor (TSR) 9, thyristor-controlled reactor (TCR) 10, controller 11, TSR trigger 12, TCR trigger

Embodiment

Fig. 1 has provided a kind of dynamic power filtering compensation device of the utility model and has been used for the examples of implementation that steel rolling mill carries out harmonic and reactive power compensation, this device comprises power filter device (FC) 4, thuristor throw-in and throw-off reactor (TSR) 8 and thyristor-controlled reactor (TCR) 9, wherein power filter device 4 is connected on transformer station's high voltage bus 3, and thuristor throw-in and throw-off reactor (TSR) 8 and thyristor-controlled reactor (TCR) 9 also are connected on the low-pressure side bus 6 of rectifier transformer 5.Control circuit is made up of controller 10 and TSR trigger 11, TCR trigger 12, voltage sampling apparatus 2, current sampling device 1.

Power filter device (FC) 4 fixedly is connected on transformer station's high voltage bus 3, when reactive load power changes, intelligent controller 10 is by the voltage and current calculated signals reactive power of sampling bus end of incoming cables, relatively draw control signal with the reactive power of setting, instruction TSR trigger 11 switching TSR devices provide certain lagging reactive power, and instruction TCR trigger 12 control TCR devices provide continuously adjustable inductive reactive power compensation.Power filter device FC provides certain capacitive reactive power for electric power system, absorb harmonic wave simultaneously, thuristor throw-in and throw-off reactor TSR provides certain lagging reactive power for electric power system, and thyristor-controlled reactor TCR provides continuously adjustable lagging reactive power for electric power system.Control system is to be control core device and trigger with the single-chip microcomputer, mixes the computer assembly language program, the direct control internal memory, and calculation control speed is fast, realizes the purpose of dynamic reactive power compensation and harmonic carcellation, and dynamic responding speed can reach 20ms.Thereby realize the function of dynamic harmonic filtering of the present utility model and reactive power compensation, raising power factor.

Be described in detail execution mode of the present utility model below.

Be connected on the power filter device (FC) the 4th that is used to absorb harmonic wave and reactive power compensation on the mill transformer station high voltage bus 3, be designed to certain subharmonic series resonant tank respectively according to characteristic harmonics and the uncharacteristic harmonics number of times that mill load produced, and formation reaches the purpose that absorbs harmonic wave to the impedance path of certain subharmonic.Rectifying device normally adopts 6 commutating phases or equivalent 12 commutating phase modes, and producing harmonic number is that (6K+1) is inferior or (12K+1) inferior.Power filter device in the present embodiment (FC) 4 is designed to four groups of filters of H5, H7, H11, H13 that the L-C series filter of 5,7,11,13 subharmonic that are made of inductance and electric capacity is formed.The reactive power compensation capacity is according to calculated load on the bus 3, and the harmonic compensation capacity that fully takes into account again on the bus 3 designs.When ordinary production, power filter device (FC) 4 is connected on the bus 3 and immobilizes.

Thuristor throw-in and throw-off reactor (TSR) 8 and the thyristor-controlled reactor (TCR) 9 that after the low-pressure side of rectifier transformer inserts by the thyristor inverse parallel of same size, are composed in series with inductance, thuristor throw-in and throw-off reactor (TSR) 8 its pilot angle α 1 are 90 ° (seeing α 1 among Fig. 1), promptly otherwise complete shut-down disconnected, full conducting, current waveform is sinusoidal wave, finishes the purpose of the certain reactive power that absorbs appointment fast.Thyristor-controlled reactor (TCR) 9 its pilot angle α 2 regulate (seeing α 2 among Fig. 1) between 90 ° and 180 °, for the certain fluctuation range of load, thyristor-controlled reactor (TCR) can dynamically be regulated reactive power fast continuously.

Controller 10 is by current sensing means 1, voltage check device 2 is sample rate current signal and voltage signal respectively, calculate the total reactive power of high voltage bus section 3, compare with the reactive power of setting, when detecting total reactive power and occur sending, at this moment, rectifier transformer 5 is at Light Condition, intelligent controller 10 sends instruction, absorb certain reactive power by TSR trigger 11 switching reactors (TSR) 8 quick (less than 20ms), in order to offset the capacitive reactive power that power filter device 4 sends, stop reactive power to be sent, simultaneously, controller 10 sends instruction, change the size that trigger angle α 2 (2≤180 ° of 90 °≤α) regulate the reactive power that fluctuates continuously by TCR trigger 12, make the total reactive power of bus 3 near 0, power factor is near 1.When controller 10 detects total reactive power is perceptual when idle, illustrate that milling train is in steel rolling, controller 10 quick (less than 20ms) makes thuristor throw-in and throw-off reactor (TSR) 8 excisions, simultaneously, regulate the size of fluctuation reactive power by the trigger angle α 2 (2≤180 ° of 90 °≤α) of TCR trigger 12 changes, make the total reactive power of bus 3 near 0, power factor is near 1.

Therefore, a kind of dynamic power filtering compensation device of the utility model, the simple and reliable practicality of its main circuit (FC+TSR+TCR) and control circuit (is control core device, trigger, voltage sampling apparatus, current sampling device with singlechip CPU 80C196), reduced investment, it is few to spend.Be particularly suitable for steel rolling mill's department substation and be used for quick compensating power, improve power factor and harmonic,, improve the purpose of the stability of electric power system to reach the quality of power supply of improving electric power system.

Claims

1, a kind of dynamic power filtering compensation device, it is characterized in that: it is made up of main circuit and control circuit, its main circuit comprises the power filter device (FC) that is installed on transformer station's high voltage bus, be installed in the rectification step-down press on the bus by thuristor throw-in and throw-off reactor (TSR) that is composed in series with inductance after the thyristor inverse parallel of same size and thyristor-controlled reactor (TCR); The control signal that its control circuit comprises the controller handled from the voltage sampling apparatus of transformer station's high voltage bus up-sampling and current sampling device, with sampled signal, send controller is delivered to the trigger of thyristor reactor.

2, a kind of dynamic power filtering compensation device according to claim 1 is characterized in that: described power filter device FC is made up of H5, H7, H11, H13 No. four harmonic filters.

3, a kind of dynamic power filtering compensation device according to claim 1 and 2 is characterized in that: described controller and trigger are to adopt with singlechip CPU 80C196 chip as control board.