CN201259375Y - Energy saving consumption lowering synthetic electricity saving system for electric smelting magnesia - Google Patents

Abstract

The utility model relates to an energy-saving consumption-reducing comprehensive electricity-saving system of a fused magnesite sand furnace, which is characterized in that a main circuit is connected with a connection cable through the upper part of a disconnecting link, and the lower end of the disconnecting link is connected with a bus bar, and the bus bar is connected with a plurality of circuits of over-current protecting device, and the lower end of the protecting device is connected with a vacuum contactor, and the lower end of other contactors is connected with a filter reactor, and the lower end of the reactor is connected with a compensation capacitor; the input end of a powerless compensation controller of a control system is accessed to both sides of a current mutual inductor of a power-supply circuit, and the output end is connected with a coil loop of the vacuum contactor; the input end of a relay protector is accessed into a current mutual inductor of the main circuit, and an output loop is accessed into a breaking coil of the vacuum contactor of the main circuit. The energy-saving consumption-reducing comprehensive electricity-saving system has the advantages that through the sampling and the judgment of the power-supply network parameters and the elevation position of the electrodes in the fused magnesite sand furnace, the powerless power is automatically compensated, and the harmful ultraharmonics is filtered, thereby can automatically adjust the increase of the electrode, and realizing the three-phase power balance, and realizing the electricity conservation and the loss reduction.

Description

The electric magnesite-smelting furnace integrated power-saving system that saves energy and reduce the cost

Technical field

The utility model belongs to a kind of electric magnesite-smelting furnace energy saving device, and is particularly a kind of by reactive-load compensation, filtering harmonic wave, three-phase power balance control technology, realizes the integrated power-saving system of electric-melting magnesium electric power energy-saving consumption reduction.

Background technology

In the fused magnesia smelting process, electrode arc heating ore because perceptual arcing makes the electric power factor lower, has only about 0.75, causes power attenuation, the waste electric energy; Secondly subsidiaryly also produce a large amount of higher hamonic waves, these harmonic waves not only make line loss increase, but also produce additional torque on electricity-measuring meter, cause the overdose of kilowatt-hour meter and cause unnecessary electricity charge loss; The 3rd Electrode for remelting owing to reasons such as sinking of mineral aggregate cause three-phase electrode deep mixed causing in material, causes the three phase electric power imbalance in burner hearth, influenced output and quality.Therefore, how to solve an above-mentioned difficult problem and realize that big power consumer's electric-melting magnesium industry integrated power-saving just seems very necessary.

The utility model content

The purpose of this utility model is: filtering higher hamonic wave and reactive-load compensation develop simultaneously and take into account.Overcome and only note reactive-load compensation in the past, and ignored improvement to harmful higher hamonic wave, though its consequence is to have improved power factor but seriously amplified higher hamonic wave, the problem that on consumption reduction, loses more than gain, and electricity-measuring meter produces additional torque, causes overdose and pays the problem of the electricity charge more.At above-mentioned drawback, carrying out reactive-load compensation, when improving power factor, adopted the multiple filter technology that harmful higher hamonic wave is carried out the comprehensive regulation, solved above-mentioned drawback.Filtering/compensation is two to be taken into account thereby reach, the purpose of economize on electricity consumption reduction.

The purpose of this utility model is achieved in that it comprises main circuit, control system, is characterized in that:

Main circuit is to link to each other with stube cable by disconnecting link top, the lower end of disconnecting link links to each other with bus row, bus row link to each other with multichannel overcurrent protector, the lower end of protector links to each other with vacuum contactor, its contactor lower end links to each other with filter reactor, reactor lower end and compensation condenser join, and constitute a complete main circuit that five filtering compensation loops are arranged;

Control system is provided with idle compensating control and three-phase electrode lifting automatic controller, and wherein: the input of idle compensating control seals in the secondary side of the current transformer of supply line, the wire loop of its output termination vacuum contactor; The input of three-phase electrode lifting controller seals in the secondary side of the current transformer of supply line, and the output termination drags the start and stop loop of the motor of rise fall of electrodes.

The utility model has the advantages that: by sampling and judgement the lifting position of electrode in power supply network parameter and the molten magnesium burner hearth, to the higher hamonic wave that reactive power compensates automatically and filtering is harmful, can also regulate the lifting of electrode automatically, reach three-phase power balance, fall the purpose of damage thereby realized effectively economizing on electricity.

Description of drawings

Fig. 1 is the theory diagram that the utility model is used for the integrated power-saving system.

Fig. 2 is the circuit theory schematic diagram that the utility model is used for the integrated power-saving system.

Fig. 3 is the utility model control circuit schematic diagram.

Symbol description among the figure:

A: supply network 66KV

B: substation transformer 66KV/10KV

C: electric furnace power supply network 10KV

D: furnace transformer 10KV/0.14KV

E: the short net system (low-voltage and high-current) of electric furnace smelting

F: copper bar and cable

G: three-phase electrode system

H: melting burner hearth

1# gathers: the power network signal sampler

2# gathers: short net signal sampler

Controller: filtering/compensating controller

The specific embodiment

See Fig. 1-3, the utility model comprises main circuit, control system: main circuit is to link to each other with stube cable by disconnecting link DZ top, the lower end of disconnecting link DZ and bus row link to each other, and bus is arranged and linked to each other with multichannel overcurrent protector BX1-BX5, the lower end of each protector respectively with vacuum contactor ZK!-ZK5 links to each other, and its contactor lower end links to each other with filter reactor LK1-LK5 respectively, each reactor lower end respectively with compensation condenser C!-C5 joins, and constitutes a complete main circuit that five filtering compensation loops are arranged;

Control system is provided with idle compensating control and three-phase electrode lifting automatic controller, wherein: the input L1-L12 of idle compensating control seals in the secondary side of the current transformer of supply line, and its output LC1-LC10 connects the wire loop of vacuum contactor ZK; Input R1-the R12 of three-phase electrode lifting controller seals in the secondary side of the current transformer of supply line, and output RD1-RD6 connects the start and stop loop of the motor that drags rise fall of electrodes.

The utility model is used for the circuit theory of integrated power-saving system: primary side voltage, current signal are sent into collector No. 1 as shown in Figure 2.Collector is sent into three-phase and all single-phase electric parameters through after the computing to the software of controller, comprise electrical parameters such as primary side current I, voltage V, active power P, reactive power Q, general power S, power factor COS φ, three-phase power imbalance and show that as data wherein the primary side power factor is as pilot signal; Secondary side voltage is sent into collector No. 2, and collector is sent into three-phase and single-phase voltage parameter through after the computing to the software of controller, and wherein the secondary side voltage parameter is as pilot signal.Smelt voltage by adjustable primary side power factor of parameter and secondary side and set the primary side power factor of operation and secondary side and smelt voltage parameter and send in the controller, send control signal by controller after the calculation process, regulate the three-phase compensation capacity respectively.

What reactive-load compensation reduced is the preceding circuit reactive loss of access point, according to this principle, concrete condition at the short net of electric magnesite-smelting furnace low-pressure side, make the reactive compensation system that connects on the compensation point can bucking-out system as much as possible idle, take into account simultaneously the reasonable access of short net again, reduce the influence that unfavorable factors such as smelting high ambient temperature and Operation and Maintenance is brought, therefore the second compensation tie point is selected on the tie point of netting with the top of electrodes weak point, do not only having compensated reactive loss to greatest extent but also avoided the cable of access point not burned like this, thereby guaranteed the safe operation of reactive compensation system by electric furnace high temperature.

Integrated power-saving system works principle: according to the requirement of electric magnesite-smelting furnace matallurgical products and technology to voltage and arc power, form with numeral is set electric current, power, and computer control system automatically detected in real time parameter value (voltage, electric current) is carried out the A/D conversion.By the AD conversion line arc voltage, arc stream direct current mean value are converted to the discernible digital quantity signal of computer, send into industrial control computer, handle through fuzzy control software, provide the system works instruction, thereby the D/A conversion line changes the digital quantity command signal lifting of into d. c. voltage signal control electrode, reaches the purpose that electric current is regulated and power is controlled.In self-regulating process, according to different electric current set-points and overcurrent degree, according to fuzzy control principle, system adopts different response curves and takes into account the three-phase power balance situation and regulate.According to decision operation respective frequencies and corresponding polarity, rotate and then drive electrode with drive motors and move up and down, change arc stream, watt level, make system's correction of deviation promptly, keep it and operate in given range.

Claims (1)

1, the energy-saving and cost-reducing integrated power-saving system of a kind of electric magnesite-smelting furnace, it comprises main circuit, control system, it is characterized in that:

Main circuit is to link to each other with stube cable by disconnecting link top, the lower end of disconnecting link links to each other with bus row, bus row link to each other with multichannel overcurrent protector, the lower end of protector links to each other with vacuum contactor, its contactor lower end links to each other with filter reactor, reactor lower end and compensation condenser join, and constitute a complete main circuit that five filtering compensation loops are arranged;

Control system is provided with idle compensating control and three-phase electrode lifting automatic controller, and wherein: the input of idle compensating control seals in the secondary side of the current transformer of supply line, the wire loop of its output termination vacuum contactor; The input of three-phase electrode lifting controller seals in the secondary side of the current transformer of supply line, and the output termination drags the start and stop loop of the motor of rise fall of electrodes.

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