CN201656495U - Secondary reactive power compensation control system for ore heating furnace - Google Patents
Secondary reactive power compensation control system for ore heating furnace Download PDFInfo
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- CN201656495U CN201656495U CN2010203009486U CN201020300948U CN201656495U CN 201656495 U CN201656495 U CN 201656495U CN 2010203009486 U CN2010203009486 U CN 2010203009486U CN 201020300948 U CN201020300948 U CN 201020300948U CN 201656495 U CN201656495 U CN 201656495U
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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- Y02E40/30—Reactive power compensation
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Abstract
The utility model relates to a secondary reactive power compensation control system for ore heating furnace, which belongs to the reactive power compensation field of ore heating furnace used for smelting. The three-phase inequality cyclical switchover of the secondary reactive power compensation device and operation state monitor of the ore heating furnace are achieved. The utility model is characterized in that it comprises a master control computer, a display, an input equipment, two conversion interfaces, two intelligent electric converters, a primary side voltage transformer, a primary side current transformer, a secondary voltage transformer, a secondary current transformer, a programmable controller, a temperature transmitter, a compensation device, an alarm device, a transmission standard interface and a power-supply system. The utility model has advantages of improving power factor, increasing effective output rate of the transformer of an ore heating furnace, reducing loss, decreasing three-phase unbalance degree, increasing output, improving automation degree and enhancing man-machine interaction.
Description
Technical field
The utility model relates to the reactive power compensation field that smelts with the hot stove in ore deposit, realizes the hot furnace operating state monitoring of three-phase inequality switching cycle and ore deposit of submerged arc furnace secondary reactive compensation device, is a kind of submerged arc furnace secondary reactive compensation control system.
Background technology
The electrical system of the hot stove in ore deposit mainly is made up of high voltage supply network, furnace transformer, compensator, short net, water-cooling system, electrode system, burner hearth and control system, its load characteristic between resistive and perceptual between, the short net of low-voltage and high-current and the structure and the work characteristics of water-cooling system, the natural power factor of the hot stove in decision ore deposit is difficult to reach more than 0.85, so just need carry out reactive power compensation to supply line, with power factor is brought up to national regulation 0.90 or more than, to reach the purpose of balance electric network reactive-load.Present power supply department and ferroalloy enterprise more options high pressure compensation, this compensation way is that capacitor is parallel on the three-phase bus of high pressure primary side, its investment is little, but can not adapt to load variations in the stove production process, overcompensation or undercompensation phenomenon can appear, also do not have simultaneously the effect of energy-saving and production-increase, control method is manual control.And more satisfactory be to carry out reactive power compensation in the ore furnace secondary side, the loop stream mistake that secondary reactive compensation can make a large amount of reactive currents directly form through special-purpose secondary capacitor and electric arc, and no longer through short net, transformer and power supply network before the compensation point, when improving power factor, also can improve transformer and exert oneself, reduce the wastage.At present the submerged arc furnace secondary reactive compensation control system mostly is with power factor controller or PLC control, and the image data amount is few, and control precision is not high, and control mode is single, and the time have overcompensation or undercompensation phenomenon to occur, do not reach best compensation effect.
Summary of the invention
The purpose of this utility model just provides a kind of submerged arc furnace secondary reactive compensation control system that can finish appointed task in complex environment and guarantee the overall system performance optimum, improves power factor to reach, strengthens the effective output rating of ore heat furnace transformer, reduces the wastage, reduces tri-phase unbalance factor, increases output, improves automaticity and strengthens the purpose of human-computer interaction function.
For achieving the above object, technical solution of the present utility model is: the submerged arc furnace secondary reactive compensation control system is characterized in that: comprise main control computer, display, input equipment, two translation interfaces, two intelligent electric power transmitters, primary side voltage transformer, primary side current instrument transformer, secondary side voltage transformer, secondary side current instrument transformer, Programmable Logic Controller, temperature transmitter, compensation arrangement, warning device and transmission standard interface and power-supply systems; Wherein,
Main control computer is electrically connected with display and input equipment, and main control computer is electrically connected with the transmission standard interface by two translation interfaces, connects intelligent electric power transmitter and Programmable Logic Controller respectively by the transmission standard interface;
A port of one of two intelligent electric power transmitters is electrically connected by the transmission standard interface, and port is electrically connected primary side voltage transformer and primary side current instrument transformer respectively in addition; A port of another of two intelligent electric power transmitters is electrically connected by the transmission standard interface, and port is electrically connected secondary side voltage transformer and secondary side current instrument transformer respectively in addition;
Programmable Logic Controller PLC connects and connects compensation arrangement C, warning device AL and temperature transmitter T respectively, is responsible for switching, the reception of alarm signal and the reception and the execution of transmission and temperature protection signal of control compensation device C;
The primary side voltage transformer links to each other with power transducer respectively with secondary side current instrument transformer, voltage transformer summation current transformer with primary side current instrument transformer and secondary side voltage transformer, be used for to main control computer provide ore heat furnace transformer once with the secondary low-voltage side data, and these data are handled, analyze, judge, are stored and reconstitute control command by main control computer and control corresponding compensation arrangement.
Described main control computer is handled, analyzes, judges, is stored these data and reconstitute control command and controls corresponding compensation and comprise the steps:
1) after the user moved main program, initialization subroutine (S101) at first called in system.
2) judge ore heat furnace transformer primary side voltage whether normally (S102) then.
3), then judge ore heat furnace transformer primary side current whether normally (S103) if ore heat furnace transformer primary side voltage is normal; Otherwise excision electric capacity and report to the police (S106).
4) whether normally above-mentioned judged result (S103) if the ore heat furnace transformer primary side current is normal, then judges ore heat furnace transformer secondary side voltage (S104); Otherwise excision electric capacity and report to the police (S106).
5) whether normally above-mentioned judged result (S104) if ore heat furnace transformer secondary side voltage is normal, then judges short net of ore heat furnace transformer secondary side and capacitor temperature (S105); Otherwise excision electric capacity and report to the police (S106).
6) above-mentioned judged result (S105) if short net of ore heat furnace transformer secondary side and capacitor temperature are normal, then judges whether automatic operation (S108); Otherwise excision electric capacity and report to the police (S106).
7) then to excision electric capacity and warning (S106), whether judging reports to the police recovers normal (S107).
8) above-mentioned judged result (S107) if system alarm does not reset, then reverts to above-mentioned steps (S102); If system alarm resets, then continue to carry out (S108).
9) above-mentioned judged result (S108) if system controls automatically, is called switching subprogram (S109), otherwise finishes.
Described switching control method comprises the steps:
1) enter the switching subprogram after, at first judge whether anxious stop (S201).
2) above-mentioned judged result (S201) is if urgency is stopped then return; Otherwise judge power factor whether low (S202).
3) above-mentioned judged result (S202) if power factor is low, judges then whether this low phase of power factor throws full (S203).
4) above-mentioned judged result (S203) expires if thrown, and then returns; Otherwise judge whether drop into time-delay arrives (S204).
5) above-mentioned judged result (S204) does not arrive if drop into time-delay, then returns; Otherwise drop into capacitor (S205) in proper order.
6) then, revert to above-mentioned steps (S203).
7) follow above-mentioned judged result (S202),, then judge power factor whether high (S206) if power factor is not low.
8) above-mentioned judged result (S206) is if the power factor height judges then whether this high phase of power factor has excised finish (S207).
9) above-mentioned judged result (S207) if excision finishes, is then returned; If excision does not finish, judge then whether the excision time-delay arrives (S208).
10) above-mentioned judged result (S208) if the excision time-delay is not arrived, is then returned; If the excision time-delay is arrived, then excise capacitor (S209) in proper order.
11) then, revert to above-mentioned steps (S207).
12) follow above-mentioned judged result (S206),, then judge whether balance (S210) of active power if power factor is not high.
13) above-mentioned judged result (S210) is if balance is then returned; If uneven, judge then whether of active power minimum has thrown full (S211) mutually.
14) above-mentioned judged result (S211) expires if thrown, then returns; Do not expire if throw, otherwise judge whether drop into time-delay arrives (S212).
15) above-mentioned judged result (S212) does not arrive if drop into time-delay, then returns; Otherwise drop into capacitor (S213) in proper order.
16) then, revert to above-mentioned steps (S210).
Characteristics of the present utility model and effect have:
1. adopt two intelligent electric power transmitter P1 and P2 to gather respectively in real time the electric parameter of the short net of ore heat furnace transformer primary side and secondary, make that information is comprehensive, parameter is complete, control provides the hardware assurance for main control computer PC implements accurately.
2. main control computer PC is powerful, is responsible for finishing tasks such as data processing and storage, algorithm are implemented, control output, adopts high-level programming language to realize that the multithreading task handles, for the walking abreast of each modular system, co-ordination provide the software assurance.
3. adopt the RS485 bus to connect each control module, data and information sharing when having guaranteed The whole control system work also provide and have made things convenient for approach for adding new control module.
4. control system is done host computer with main control computer PC, Programmable Logic Controller PLC does slave computer, and host computer PC is given an order to slave computer PLC, makes PLC carry out decentralized control, by the monitoring of host computer, availablely realize the automatically-monitored of process of factory production easily to PLC.
5. display D provides the graphical interaction interface, and input equipment KM provides the interactive operation of operating personnel H and control system, includes the people in closed-loop control system simultaneously, the operating state and the treatment system abnormal conditions that be responsible for assigning control command, monitor the hot stove in ore deposit.
Description of drawings
With reference to the accompanying drawings to the utility model embodiment do one the step be described in detail as follows:
Fig. 1 is a submerged arc furnace secondary reactive compensation system block diagram of the present utility model;
Fig. 2 is a submerged arc furnace secondary reactive compensation of the present utility model system main program flow chart;
Fig. 3 is the switching subroutine flow chart of Fig. 2.
Embodiment
As shown in Figure 1, control system also comprises main control computer PC, display D, input equipment KM (keyboard, mouse), two translation interface RS1 and RS2, two intelligent electric power transmitter P1 and P2, primary side voltage transformer V1, primary side current instrument transformer A1, secondary side voltage transformer V2, secondary side current instrument transformer A2, Programmable Logic Controller PLC, temperature transmitter T, compensation arrangement C, warning device AL and asynchronous transmission standard interface RS232 except that power-supply system PS.Main control computer PC is electrically connected with display D and input equipment KM (keyboard, mouse), main control computer PC is electrically connected with RS485 or RS232 transmission standard interface by two translation interface RS1 and RS2, connects intelligent electric power transmitter P1, P2 and Programmable Logic Controller PLC respectively by RS485 or RS232 transmission standard interface; The port of intelligent electric power transmitter P1 is electrically connected by the transmission standard interface, and the other port of intelligent electric power transmitter P1 is electrically connected primary side voltage transformer V1 and primary side current instrument transformer A1 respectively; The port of intelligent electric power transmitter P2 is electrically connected by the transmission standard interface, and port is electrically connected secondary side voltage transformer V2 and secondary side current instrument transformer A2 respectively in addition; Programmable Logic Controller PLC connects and connects compensation arrangement C, warning device AL and temperature transmitter T respectively, is responsible for switching, the reception of alarm signal and the reception and the execution of transmission and temperature protection signal of control compensation device C; The primary side voltage transformer links to each other with power transducer respectively with secondary side current instrument transformer, voltage transformer summation current transformer with primary side current instrument transformer and secondary side voltage transformer.
1) main control computer PC is the core that guarantees the control system performance, is responsible for tasks such as real-time detection, numerical computations, information processing, algorithm realization, process control.Simultaneously,, control the data acquisition of two intelligent electric power transmitter P1 and P2, handle control compensation device C, and realize that the signal of warning device A sends and controlling alarm by Programmable Logic Controller PLC by the RS232 interface.
2) display D links to each other with main control computer PC, is the interactive interface of operating personnel H and control system, is responsible for parameter setting, data demonstration, compensation arrangement and work such as demonstration of power transducer operating state and the indication of switching capacity.
3) input equipment KM links to each other with main control computer PC, is the interactive means of operating personnel H and control system, is responsible for work such as parameter input, picture location, system operation and manual switching.
4) voltage transformer V1 and V2 link to each other with P2 with power transducer P1 respectively, are responsible for the detection of primary side and secondary side voltage signal, and output signal to power transducer P1 and P2.
5) current transformer A1 and A2 link to each other with P2 with power transducer P1 respectively, are responsible for the detection of primary side and secondary side current signal, and output signal to power transducer P1 and P2.
6) power transducer P1 and P2 are responsible for data acquisition, processing and the storage of voltage transformer V1 and V2, current transformer A1 and A2, and data are sent to main control computer PC by translation interface RS1 and RS2.
7) translation interface RS1 and RS2, be responsible for the communication of power transducer P1 and P2 and Programmable Logic Controller PLC and main control computer PC respectively, realize that single-ended RS-232 signal is to the RS-422 of balanced differential or the conversion of RS-485 signal, the isolation voltage of 2500V is provided, effectively suppress surge, thunderbolt and disturb altogether, guarantee the reliable and stable of communication.
8) Programmable Logic Controller PLC connects and connects compensation arrangement C, warning device AL and temperature transmitter T respectively, is responsible for switching, the reception of alarm signal and the reception and the execution of transmission and temperature protection signal of control compensation device C.
9) compensation arrangement C, PLC is connected with Programmable Logic Controller, is the body of control system control, is responsible for the input and the excision of compensation arrangement, to improve power factor, to regulate tri-phase unbalance factor.
10) warning device AL is connected with Programmable Logic Controller PLC, and alarm signal sends when being responsible for the system failure.
11) temperature transmitter T is connected with Programmable Logic Controller PLC, is responsible for selection of temperature signal, judgement, and the temperature protection signal is offered Programmable Logic Controller PLC.
12) RS232 be connect translation interface RS1 and RS2 and with the physical channel of main control computer PC, data and information sharing when having guaranteed control system work.
Suppose that compensation arrangement C carries out the switching operation task in the course of the work.
At first, bucking-out system and device C are according to automated manner operation down, main control computer PC comprehensively from temperature transmitter T and the alarm signal of warning device AL and electric signal and the information of power transducer P1 and P2 of Programmable Logic Controller PLC, carries out analyzing and processing and initialization operation.
Main control computer is handled, analyzes, judges, is stored these data and reconstitute control command and controls corresponding compensation arrangement as shown in Figure 2, comprises the steps:
1) after the user moved main program, initialization subroutine (S101) at first called in system.
2) judge ore heat furnace transformer primary side voltage whether normally (S102) then.
3), then judge ore heat furnace transformer primary side current whether normally (S103) if ore heat furnace transformer primary side voltage is normal; Otherwise excision electric capacity and report to the police (S106).
4) whether normally above-mentioned judged result (S103) if the ore heat furnace transformer primary side current is normal, then judges ore heat furnace transformer secondary side voltage (S104); Otherwise excision electric capacity and report to the police (S106).
5) whether normally above-mentioned judged result (S104) if ore heat furnace transformer secondary side voltage is normal, then judges short net of ore heat furnace transformer secondary side and capacitor temperature (S105); Otherwise excision electric capacity and report to the police (S106).
6) above-mentioned judged result (S105) if short net of ore heat furnace transformer secondary side and capacitor temperature are normal, then judges whether automatic operation (S108); Otherwise excision electric capacity and report to the police (S106).
7) then to excision electric capacity and warning (S106), whether judging reports to the police recovers normal (S107).
8) above-mentioned judged result (S107) if system alarm does not reset, then reverts to above-mentioned steps (S102); If system alarm resets, then continue to carry out (S108).
9) above-mentioned judged result (S108) if system controls automatically, is called switching subprogram (S109), otherwise finishes.
Switching control method is as shown in Figure 3: comprise the steps:
1) enter the switching subprogram after, at first judge whether anxious stop (S201).
2) above-mentioned judged result (S201) is if urgency is stopped then return; Otherwise judge power factor whether low (S202).
3) above-mentioned judged result (S202) if power factor is low, judges then whether this low phase of power factor throws full (S203).
4) above-mentioned judged result (S203) expires if thrown, and then returns; Otherwise judge whether drop into time-delay arrives (S204).
5) above-mentioned judged result (S204) does not arrive if drop into time-delay, then returns; Otherwise drop into capacitor (S205) in proper order.
6) then, revert to above-mentioned steps (S203).
7) follow above-mentioned judged result (S202),, then judge power factor whether high (S206) if power factor is not low.
8) above-mentioned judged result (S206) is if the power factor height judges then whether this high phase of power factor has excised finish (S207).
9) above-mentioned judged result (S207) if excision finishes, is then returned; If excision does not finish, judge then whether the excision time-delay arrives (S208).
10) above-mentioned judged result (S208) if the excision time-delay is not arrived, is then returned; If the excision time-delay is arrived, then excise capacitor (S209) in proper order.
11) then, revert to above-mentioned steps (S207).
12) follow above-mentioned judged result (S206),, then judge whether balance (S210) of active power if power factor is not high.
13) above-mentioned judged result (S210) is if balance is then returned; If uneven, judge then whether of active power minimum has thrown full (S211) mutually.
14) above-mentioned judged result (S211) expires if thrown, then returns; Do not expire if throw, otherwise judge whether drop into time-delay arrives (S212).
15) above-mentioned judged result (S212) does not arrive if drop into time-delay, then returns; Otherwise drop into capacitor (S213) in proper order.
16) then, revert to above-mentioned steps (S210).
Claims (2)
1. the submerged arc furnace secondary reactive compensation control system is characterized in that: comprise main control computer, display, input equipment, two translation interfaces, two intelligent electric power transmitters, primary side voltage transformer, primary side current instrument transformer, secondary side voltage transformer, secondary side current instrument transformer, Programmable Logic Controller, temperature transmitter, compensation arrangement, warning device and transmission standard interface and power-supply systems; Wherein,
Main control computer is electrically connected with display and input equipment, and main control computer is electrically connected with the transmission standard interface by two translation interfaces, connects intelligent electric power transmitter and Programmable Logic Controller respectively by the transmission standard interface;
A port of one of two intelligent electric power transmitters is electrically connected by the transmission standard interface, and port is electrically connected primary side voltage transformer and primary side current instrument transformer respectively in addition; A port of another of two intelligent electric power transmitters is electrically connected by the transmission standard interface, and port is electrically connected secondary side voltage transformer and secondary side current instrument transformer respectively in addition;
Programmable Logic Controller PLC connects and connects compensation arrangement C, warning device AL and temperature transmitter T respectively, is responsible for switching, the reception of alarm signal and the reception and the execution of transmission and temperature protection signal of control compensation device C;
The primary side voltage transformer links to each other with power transducer respectively with secondary side current instrument transformer, voltage transformer summation current transformer with primary side current instrument transformer and secondary side voltage transformer, be used for to main control computer provide ore heat furnace transformer once with the secondary low-voltage side data, and these data are handled, analyze, judge, are stored and reconstitute control command by main control computer and control corresponding compensation arrangement.
2. submerged arc furnace secondary reactive compensation control system according to claim 1 is characterized in that: described main control computer is handled, analyzes, judges, is stored these data and reconstitute control command and controls corresponding compensation.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2010203009486U CN201656495U (en) | 2010-01-19 | 2010-01-19 | Secondary reactive power compensation control system for ore heating furnace |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2010203009486U CN201656495U (en) | 2010-01-19 | 2010-01-19 | Secondary reactive power compensation control system for ore heating furnace |
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| CN2010203009486U Expired - Fee Related CN201656495U (en) | 2010-01-19 | 2010-01-19 | Secondary reactive power compensation control system for ore heating furnace |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102252531A (en) * | 2011-04-29 | 2011-11-23 | 青海华博科技有限公司 | Submerged-arc furnace controller with low-pressure reactive compensation and electrode current control |
| CN101783515B (en) * | 2010-01-19 | 2012-02-01 | 西安科技大学 | Submerged arc furnace secondary reactive compensation control system and method |
| CN109357541A (en) * | 2018-10-17 | 2019-02-19 | 宁夏晟晏实业集团能源循环经济有限公司 | A kind of mineral hot furnace thermometric surveys pressure communication transfer device |
-
2010
- 2010-01-19 CN CN2010203009486U patent/CN201656495U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101783515B (en) * | 2010-01-19 | 2012-02-01 | 西安科技大学 | Submerged arc furnace secondary reactive compensation control system and method |
| CN102252531A (en) * | 2011-04-29 | 2011-11-23 | 青海华博科技有限公司 | Submerged-arc furnace controller with low-pressure reactive compensation and electrode current control |
| CN102252531B (en) * | 2011-04-29 | 2013-04-10 | 青海华博科技有限公司 | Submerged-arc furnace controller with low-pressure reactive compensation and electrode current control |
| CN109357541A (en) * | 2018-10-17 | 2019-02-19 | 宁夏晟晏实业集团能源循环经济有限公司 | A kind of mineral hot furnace thermometric surveys pressure communication transfer device |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20101124 Termination date: 20150119 |
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| EXPY | Termination of patent right or utility model |