CN2527016Y

CN2527016Y - Hybrid reactive power generator

Info

Publication number: CN2527016Y
Application number: CN 02209672
Authority: CN
Inventors: 韩英铎; 童路园; 张玉良; 马振库; 刘宝珩; 夏金娟; 耿俊成
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-01-11
Filing date: 2002-01-11
Publication date: 2002-12-18
Anticipated expiration: 2012-01-11

Abstract

The utility model relates to a hybrid reactive power generator applied to power system to strongly support reactive power and voltage, and comprises a startup rectifier, a GTO inverter bridge, a DC capacitor bank, a inverter output transformer, a connection transformer, a high voltage switchgear cabinet, a control unit, a detection unit, a protection unit and a cooling system and so on. The utility model is characterized by small volume, low cost and output voltage harmonic content, which can provide a reactive support to stable load with volume lower than a reactive power compensator by 15 to 30 percent. The utility model can be applied to an electric power system to ensure the safe, economy and rational operation of an electricity grid, improve electric energy quality in a user terminal, overcome the damages caused by voltage fluctuation, flicker and asymmetric operation generated in arc furnace and electrified railway system, solve voltage distortion of electricity grid caused by impact load of a rolling mill or a winch and the contamination of electricity grid caused by high order harmonic, so as to improve electric energy quality and product quality.

Description

HSVG

Technical field the utility model relates to a kind of being applied in the electric power system, plays the HSVG of the strong supporting role of reactive power and voltage.

Background technology is present, and traditional silent oscillation reactive power compensator is all adopted in the compensation and the improvement of reactive power impact, voltage fluctuation, voltage flicker and the high order harmonic component that produces in domestic procedure for steel rolling in metallurgical industry and the electric-arc furnace steelmaking production process.This kind device since its control rate due to, undesirable for the regulation effect of voltage flicker.Exist its power loss bigger simultaneously, the bad deficiency that waits of electric current one voltage characteristic.The control device shortage and the level of domestic electrical network are lower, be installed in the overwhelming majority in the electrical network and provide that quiescent voltage is regulated and the electric capacity of compensating reactive power and load tap changer adjusting, it is the key factor of restriction electric power transfer, also is the potential risk that power system collapse possible take place.At present, because the development that modern power electronics technology makes rapid progress, the novel high-power height is withstand voltage, turn-off the appearance of power electronic device fast, produced the flexible AC transmission technology thereupon, this is the forward position high-tech that International Power circle competitively developed since the nineties, be to transform traditional AC transmission system with modernized high-power electric and electronic technology and control technology, make it move Anqing reliable and economic more, make traditional AC transmission system have higher flexibility and flexibility, transmission line is fully used, to satisfy power system security, the target of reliable and economical operation.Since doctor N.G.Hingorani of American Electric Power research institute (EPRI) proposed the flexible AC transmission technological concept in 1986, the flexible AC transmission technology has just obtained great development, and multiple flexible AC transmission technical equipment appearred, controllable series compensation, static compensator (STATCOM/ASVG) are the most representative a kind of, but the reactive power generator device that several countries such as U.S., day, moral develop all is not a mixed type.

Summary of the invention the utility model HSVG is applied in the electric power system, the strong support that reactive power and voltage are had, purpose is rationally to move for the safety and economy that guarantees electrical network, be used for the harm that voltage fluctuation, flickering and asymmetric operation produced that user side improves the quality of power supply, solves arc furnace and the generation of electric railway system, solve rolling mill, the caused line voltage distortion of hoist engine impact load, and higher harmonic current is to the pollution of electrical network, to improve the quality of power supply, improve the quality of products.

The utility model HSVG content Description:

The utility model HSVG, form by reactive power generator and filter two parts, determine according to required compensation capacity, it is characterized in that: reactive power generator is formed by starting rectifier, GTO inverter bridge, direct current capacitor group, output transformer of inverter, connection transformer, high-tension switch cabinet, control unit, detecting unit, protected location and cooling system etc.; Output transformer of inverter makes HSVG be connected reactance with system with the leakage reactance that is connected transformer; Voltage inverter output phase and amplitude all can be regulated symmetrical fundamental frequency three phase sine alternating voltage; Can with systems exchange active power or reactive power; There is not the reactive power generator of power consumption to realize and AC system exchange reactive power by changing its output voltage amplitude; When output voltage amplitude during greater than the system voltage amplitude, the reactive power of lag output; When output voltage amplitude during, absorb the reactive power that lags behind and play reactor less than the system voltage amplitude; When output voltage amplitude equates with the system voltage amplitude, and will there be the exchange of reactive power between the AC system.

HSVG adopts multipleization transformer, connects 1 three-phase column-type transformer unshakable in one's determination by 4 three phase inverter bridges, and voltage transformer system then adopts 4 heavily to change the y.d wiring, adopts separate excitation or half self-excitation mode to start; When separate excitation starts, provide open-circuit excitation by a rectifier transformer for system earlier, when output voltage amplitude and phase place are identical with system voltage, merge host's switch, eliminating rectifier is exported simultaneously; When half self-excitation mode starts, block all GTO driving pulses earlier; Direct voltage is increased to zero idle operating voltage by rectifier is incorporated into the power networks then, this moment, impulse current was very little, can remove pulse blocking after being incorporated into the power networks, and HSVG puts into operation, and half self-excitation mode starts only needs the very rectifier of low capacity.

The controller of HSVG produces the trigger impulse of certain rule, after amplifying, gate drive circuit goes to control the turn-on and turn-off of GTO, make HSVG produce correct staircase voltage, according to the lock-out pulse of fetching from electrical network, produce the pulse signal synchronous with line voltage, staircase voltage and line voltage that HSVG is produced keep synchronously, thereby HSVG can correctly be incorporated into the power networks.

The utility model HSVG uses dc capacitor to keep the galvanic current source, has the advantages that capacity is little, cost is low, harmonic wave of output voltage content is little.It is idle to regulate output from specified hysteresis operating mode to specified leading operating mode continuously, under the very low situation of system voltage, still can export specified reactive current, little by 15～30% to the comparable silent oscillation reactive power compensator of the idle support capacity that steady state load is provided.HSVG has dynamic response quick-frozen faster to spend the response time less than 30 _MsAspect the power oscillation that suppresses system and the raising stability of a system best effect is being arranged, the output of every kvar can improve the transient stability limiting value of 0.5～0.7kv approximately.Have and keep the transmission line terminal voltage dynamically, improve transmission line stable state transmission power limit, improve the electric power system transient stability level, damping electric power system concussion, suppress system's overvoltage, improve system voltage stability, filter the effect of the harmonic content in the system.Can be applicable in the electric power system, play the effect of the strong support of reactive power and voltage, the safety and economy that guarantees electrical network rationally moves, can be used for the harm that voltage fluctuation, flickering and asymmetric operation produced that user side improves the quality of power supply, solves arc furnace and the generation of electric railway system again, solve rolling mill, the caused line voltage distortion of hoist engine impact load, and higher harmonic current is to the pollution of electrical network, to improve the quality of power supply and to improve the quality of products.

Description of drawings Fig. 1 constitutes block diagram for HSVG

Fig. 2 is the main circuit diagram of HSVG

Fig. 3 is the controller architecture block diagram

Embodiment the utility model HSVG is to realize like this; mixing type reactive power is made up of reactive power generator and passive filter two parts; determine according to required compensation capacity; see Fig. 1, reactive power generator is formed by starting rectifier, GTO inversion cabinet, direct current capacitor group, output transformer of inverter, connection transformer, 10KV high-tension switch cabinet, control unit, detecting unit, protected location and cooling device etc.Determine two-part capacity according to the compensation capacity size that the user is required.

1, output transformer of inverter and the leakage reactance that is connected transformer play the effect that is connected reactance of HSVG and system.

2, voltage inverter output phase and amplitude all can be regulated symmetrical fundamental frequency three phase sine alternating voltage, thus can with systems exchange active power or reactive power.

3, can change its output voltage amplitude for desirable HSVG (promptly not having power consumption) realizes and AC system exchange reactive power.

4, when HSVG output voltage amplitude during greater than the system voltage amplitude, the reactive power of HSVG lag output plays a part capacitor.

5, when HSVG output voltage amplitude during less than the system voltage amplitude, HSVG absorbs the reactive power that lags behind, and plays reactor.

6, when the HSVG output voltage amplitude equates with the system voltage amplitude, will there be the exchange of reactive power between HSVG and the AC system.

See Fig. 2, HSVG is to be example with multipleization transformer, and 4 three phase inverter bridges connect 1 three-phase column-type transformer unshakable in one's determination, and voltage transformer system then adopts 4 heavily to change the y.d wiring, adopts separate excitation or half self-excitation mode to start.When separate excitation starts, provide open-circuit excitation by a rectifier transformer for system earlier, when output voltage amplitude and phase place are identical with system voltage, merge host's switch, eliminating rectifier is exported simultaneously; When half self-excitation mode starts, block all GTO driving pulses earlier.Direct voltage is increased to zero idle operating voltage by rectifier is incorporated into the power networks then, this moment, impulse current was very little, can remove pulse blocking after being incorporated into the power networks, and HSVG puts into operation, and half self-excitation mode starts only needs the very rectifier of low capacity.

Controller produces the trigger impulse of certain rule, after amplifying, gate drive circuit goes to control the turn-on and turn-off of GTO, make HSVG produce correct staircase voltage, according to the lock-out pulse of fetching from electrical network, produce the pulse signal synchronous with line voltage, staircase voltage and line voltage that HSVG is produced keep synchronously, thereby HSVG can correctly be incorporated into the power networks.

Controller adopts the dual-locomotive heat alternate configuration, and when 1 fault, commutation circuit automatically switches to the guest machine operation, thereby improves the continuous serviceability of system; 2 controllers all can run on permanent idle mode and constant voltage unbridled, its sampling, control calculating and pulse generator all adopt the high-speed figure control mode based on 32-bit number signal processor (DSP) TMS320C31, the phase accuracy of pulse generator is guaranteed the control precision of reactive power and stability up to 0.025 °.

See Fig. 3, pulse generator is the key technology of HSVG, and is very big to the influence of control precision and stability.The fundamental positive sequence that adopts system voltage is as synchronizing signal, and obtains the synchronizing voltage zero cross signal through the simultaneous growth signal processing circuit, goes out now at the zero cross signal of each phase, begins to send corresponding PWM waveform; The generation of synchronizing signal adopts zero passage synchronous, promptly system's three-phase voltage signal is handled the back and take out a phase fundamental positive sequence voltage as synchronizing signal, when this synchronizing signal zero passage,, go out the frequency of synchronizing signal simultaneously as computation of Period by the time between 2 forwards or the negative sense zero crossing of measuring as the synchronous points of pulse generator pulse.

Claims

1, a kind of HSVG, form by reactive power generator and passive filter two parts, determine according to required compensation capacity, it is characterized in that: reactive power generator is formed by starting rectifier, GTO inverter bridge, direct current capacitor group, output transformer of inverter, connection transformer, high-tension switch cabinet, control unit, detecting unit, protected location and cooling system etc.; Output transformer of inverter makes HSVG be connected reactance with system with the leakage reactance that is connected transformer; Voltage inverter output phase and amplitude all can be regulated symmetrical fundamental frequency three phase sine alternating voltage; Can with systems exchange active power or reactive power; There is not the reactive power generator of power consumption to realize and AC system exchange reactive power by changing its output voltage amplitude; When output voltage amplitude during greater than the system voltage amplitude, the reactive power of lag output; When output voltage amplitude during, absorb the reactive power that lags behind and play reactor less than the system voltage amplitude; When output voltage amplitude equates with the system voltage amplitude, and will there be the exchange of reactive power between the AC system.

2, HSVG according to claim 1, it is characterized in that: said HSVG adopts multipleization transformer, connect 1 three-phase column-type transformer unshakable in one's determination by 4 three phase inverter bridges, voltage transformer system then adopts 4 heavily to change the y.d wiring, adopts separate excitation or half self-excitation mode to start; When separate excitation starts, provide open-circuit excitation by a rectifier transformer for system earlier, when output voltage amplitude and phase place are identical with system voltage, merge host's switch, eliminating rectifier is exported simultaneously; When half self-excitation mode starts, block all GTO driving pulses earlier; Direct voltage is increased to zero idle operating voltage by rectifier is incorporated into the power networks then, this moment, impulse current was very little, can remove pulse blocking after being incorporated into the power networks, and HSVG puts into operation, and half self-excitation mode starts only needs the very rectifier of low capacity.

3, HSVG according to claim 1, it is characterized in that: the controller of said HSVG produces the trigger impulse of certain rule, after amplifying, gate drive circuit goes to control the turn-on and turn-off of GTO, make HSVG produce correct staircase voltage, according to the lock-out pulse of fetching from electrical network, produce the pulse signal synchronous with line voltage, staircase voltage and line voltage that HSVG is produced keep synchronously, thereby HSVG can correctly be incorporated into the power networks.