CN87206999U - High precision hydrogen nitrogen proportion micro-computer controlling system - Google Patents

Abstract

The utility model is created, and the utility model belongs to the automatic controlling system. The utility model is mainly used for the fertilizer factories of producing the synthetic ammonia. The high precision controlling of the hydrogen nitrogen proportion is implemented. The key point of the controlling system is that according to the prediction principle of the division state, a part state prediction device is additionally arranged in the system, and the part state prediction device goes on with prediction for the state, and the part state prediction device goes on with controlling through a micro-computer. Therefore, the utility model efficiently overcomes large pure time delay to make the dynamic stability improved evidently and to make the control precision improved to +-0.15 given value. The qualification rate of the hydrogen nitrogen proportion can reach more than 90%. If the creation of the utility model can be popularized and used in all the country, the annual economic benefit produced by the utility model relates to 8000 myriad yuan probably.

Description

High precision hydrogen nitrogen proportion micro-computer controlling system

The invention belongs to automatic control system.

In producing the chemical fertilizer factory of synthetic ammonia, it is to be that raw material comes synthetic ammonia (NH with coal or coke that many factories are arranged ₃).In synthetic process, the proportional control that should make hydrogen and nitrogen is at 3:1.If this proportional control is bad, will directly influence output, cause waste, increase the cost of product.In order to control this hydrogen nitrogen ratio, all adopt classic method of controlling for many years both at home and abroad, constitute hydrogen nitrogen ratio control system with conventional instrument, and mostly adopt PID and tandem to regulate.Afterwards, microcomputer came out and also was applied to hydrogen nitrogen ratio control system, made the formation of system that variation take place, and added logic determines but its control thought still is PID control basically.Since coal (Jiao) hydrogen nitrogen than system exist pure retardation time long, disturbing factor is many, the complicated difficulty such as control that is difficult to of dynamic perfromance, and adopt two kinds of above-mentioned methods of controlling to fail to address these problems well, so do not reach satisfied effect, its control accuracy preferably also can only reach set-point ± 0.3.For example, though the microcomputer hydrogen nitrogen ratio control system of Shi Guan and Feicheng, Shandong chemical fertilizer factory has all passed through technical appraisement in 1985, control accuracy also can only reach set-point ± 0.3.As seen the control accuracy problem has become a control difficult problem both domestic and external.

In order to solve an above-mentioned control difficult problem, realize the High Accuracy Control of hydrogen nitrogen ratio, thereby make the chemical fertilizer production of China increase output, reduce cost, increase economic efficiency, special constitute and control thought aspect is studied and innovated from system, make the invention, and obtained satisfied effect.

The main points of the invention are, increase by one in than Control System of Microcomputer at general hydrogen nitrogen and are called partial status and give the parts of estimating device, and this is to give according to the branch state that we propose estimating principle design and coming out.Partial status gives to be estimated device 5 and is connected with pick-up unit 4 on the one hand, the relevant signal of controll plant is given estimate; Be connected with microcomputer 1 on the other hand, relevant giving estimated the result and be sent to microcomputer, carry out necessary calculating, and directly control whole system operation according to result of calculation by it.This has just overcome big pure-time-delay effectively, thereby control accuracy and dynamic stability are significantly improved.Partial status gives estimating and has comprised three (or more than three) one-parameters in the device 5 again and give and estimate device 6,7,8, and like this, they can give each hydrogen signal respectively and estimating, so that overcome the pure-time-delay that is produced on each link, improve control accuracy.Each one-parameter gives to be estimated in the device, contains some sampling holders and totalizer again, and the shift pulse that their work is sent by pulse shift unit 10 is controlled.Comprehensive totalizer 11 can be given three one-parameters and be estimated the signal that device sends here and carry out comprehensive addition, and be sent to microcomputer 1, carry out accurate calculating, signal Processing by it, and directly control total system and work without any confusion, finally reach the control of high precision hydrogen nitrogen ratio.

Accompanying drawing 1 is the general diagram of high precision hydrogen nitrogen than Control System of Microcomputer, and wherein 1 is microcomputer, and it is used to total system is carried out computing, control and management; The 2nd, topworks, the various control commands that its object computer sends; The 3rd, controll plant particularly, is exactly that hydrogen nitrogen in the synthesis ammonia system compares system; The 4th, pick-up unit is in order to measure the relevant signal in the controll plant, as gas holder hydrogen, purified hydrogen, recycle hydrogen, nitrogen content etc.; The 5th, partial status gives estimates device, and it can give in advance the relevant signal of controll plant and estimating, and reaches to overcome big pure-time-delay, thereby improves control accuracy and dynamic stability.

Accompanying drawing 2 is that partial status gives the structured flowchart of estimating device 5, and wherein 6,7,8 is that three one-parameters give and estimate device, and they give each hydrogen signal respectively and estimating, to overcome the pure-time-delay that each link is brought; The 9th, clock pulse generator, it produces trigger pip, with 10 work of driving pulse shift unit; The 10th, the pulse shift unit, it sends shift pulse, is sent to three one-parameters respectively and gives and estimate device 6,7,8; The 11st, comprehensive totalizer, it gives three one-parameters and estimates the signal that device 6,7,8 sends here and carry out comprehensively, and being sent to microcomputer 1 for information about; 1 and 4 is respectively microcomputer described in the accompanying drawing 1 and pick-up unit.

Accompanying drawing 3 is that one-parameter gives the electrical schematic diagram of estimating device 6,7,8, wherein 12,14,16 ... 2K is sampling holder, sends into these sampling holders from the signal that controll plant 3 collects through pick-up unit 4, keeps successively, estimates so that give; 13,15 ... 2K+1 is a totalizer, is responsible for sending into comprehensive totalizer 11 behind the signal superposition that keeps.(K is the natural number greater than 6, and its value is decided according to the lagged value of real system.) 10 be still said pulse shift unit in the accompanying drawing 2, as can be seen, the shift pulse that it sends is to send into one-parameter to have given in the sampling holder of estimating in the device from accompanying drawing 3, to drive their work.

The invention is succeeded in developing, and effect is excellent, has passed through the provincial-level appraisal of Henan Province planning commission, Economic and Trade Commission the end of the year 1986.The result who carries out running test in tafelberg, Henan Province chemical fertilizer factory shows, has reached fully and has given the effect of thinking.For example, China the Ministry of Chemical Industry ministerial standard regulation is produced the large and medium-sized chemical fertilizer factory of 100,000 tons of synthetic ammonia per year, the control accuracy of hydrogen nitrogen ratio should set-point ± 0.3; Produce the small fertilizer plant of synthetic ammonia below 20,000 tons per year, control accuracy should set-point ± 0.4.And the invention, the control accuracy of hydrogen nitrogen ratio reached set-point ± 0.15, improved greatly.Simultaneously, hydrogen nitrogen has also improved than 80% of contract index regulation than qualification rate, is more than 90%.Economic benefit is very remarkable, can increase production more than 3%, and every year, only tafelberg chemical fertilizer factory just can obtain 760,000 yuans of pure economic benefits.If can apply in the whole nation, issuable economic benefit is about 8,000 ten thousand yuans.The invention also will promote the rapid progress of big system's control time lag except influencing hydrogen nitrogen than the control.The invention is simple in structure, and cost is low, is easy to grasp promote.

As the most preferred embodiment of the invention, the microcomputer that is adopted is an APPLE-II microcomputer, and is promptly available on the home market, and price is more cheap.Partial status gives estimating and has comprised three one-parameters in the device 5 and give and estimate device 6,7,8.The unit, the device that constitute this control system are the home market mill run, very easily obtain.

Claims (5)

1, a kind of automatic control system, give by microcomputer 1, topworks 2, controll plant 3, pick-up unit 4 and partial status and to estimate device 5 and formed, it is characterized in that it has a partial status to give and estimates device 5, this partial status gives to be estimated device 5 and is connected with pick-up unit 4 on the one hand, is connected with microcomputer 1 on the other hand.

2, a kind of according to the said automatic control system of claim 1, it is characterized in that said partial status gives estimating comprises plural one-parameter and gives and estimate device (native system comprise 3 one-parameters give estimate device 6,7,8) in the device 5, one-parameter gives the input end of estimating device and is connected with driving pulse shift unit 10, pick-up unit 4, and output terminal is connected with comprehensive totalizer 11.

3, a kind of according to claim 1,2 said automatic control systems, it is characterized in that said one-parameter gives and estimate device (as 6,7,8) by several sampling holders 12,14,16 ... 2K and several totalizers 13,15 ... 2K+1 forms; Each sampling holder is connected in series successively, and all is connected with the output terminal of pulse shift unit 10, is subjected to the control of its shift pulse; The output terminal of each sampling holder is connected with the input end of each totalizer again successively, and the output terminal of first sampling holder 12 and pick-up unit 4 is connected; Each totalizer also is connected in series successively.The output terminal of last totalizer is connected with the input end of comprehensive totalizer 11.

4, a kind of according to claim 1,2 said automatic control systems, it is characterized in that said partial status gives estimating contains a driving pulse shift unit 10 in the device 5, the input end of driving pulse shift unit 10 is connected with microcomputer 1, clock pulse generator 9, and output terminal and one-parameter give to be estimated device 6,7,8 and be connected.

5, a kind of according to claim 1,2 said automatic control systems, it is characterized in that said partial status gives estimating contains a comprehensive totalizer 11 in the device 5, the input end of comprehensive totalizer and one-parameter give to be estimated device 6,7,8 and is connected, and its output terminal is connected with microcomputer 1.

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