CN101301596B - Power regulation and control system of cubic hydraulic press made of superhard material and control method thereof - Google Patents

Abstract

The present invention provides a power adjustment control system of a hexahedral top ultrahard material hydrostatic press and a control method thereof. The system comprises a microprocessor, a silicon controlled voltage regulator connected to the primary side of the heating transformer and a Hall sensor. The heating enactment value is provided by the host computer and other input cells and EMS memory data, the control signal is connected with the silicon controlled voltage regulator by a photoelectric isolated circuit, a signal processing module, a fuzzy control module and a PI control module are arranged in the microprocessor. The fuzzy control module has fuzzy control rule for regulating the PI parameters. The control method comprises: commuting and filtering the instantaneous value of the heating current, voltage and power by the signal processing module, calculating the current average value of the heating power and comparing to the enactment value, regulating the PI parameters in real time by the fuzzy control module and obtaining the controlled angle of the controlled silicon at the next time, stably controlling the heating power of the transformer at the enactment value. The present invention has merits of precise electricity measurement and small inertia and lag. When the voltage fluctuation of electric fence is large, the heating power can be adjusted in time, so the control precision is high and the quality of the ultrahard material compound is ensured efficiently.

Description

Cubic apparatus superhard material hydraulic press Power Regulation control system and control method thereof

(1) technical field

The present invention relates to cubic apparatus superhard material hydraulic press control system, be specially a kind of cubic apparatus superhard material hydraulic press Power Regulation control system and control method thereof.

(2) background technology

Cubic apparatus superhard material hydraulic press is by low-voltage and high-current in addition on two relative tops hammers, the electric current synthetic piece of flowing through, and synthetic piece reaches heating purposes because of the resistance heating of inside.According to thermodynamics and high-pressure physics, can calculate the pressure match curve in time of formulating heating power and hydraulic system by superhard material growth synthesis mechanism.For synthetic piece temperature inside of control and pressure are controlled entire synthesis process easily, the method of present commonplace employing is to control by the system pressure of the heating power of measurements and calculations heating system and hydraulic system and to it, can control synthetic piece internal temperature and pressure indirectly and concern over time, make it to meet synthetic material temperature, pressure match curve.

The heating power control system of present widely used cubic apparatus superhard material hydraulic press is promptly according to above-mentioned principle design.This system generally constitutes master controller with single-chip microcomputer, Programmable Logic Controller or other device, adopts D.C mutual-inductor to detect the voltage and current signal on the former limit of heating transformer and convert mean value to and is for further processing.These signals compare with the heating process parameter that prestores, and after certain control algolithm is handled, control the output voltage and the output current of heating transformer by control silicon controlled pilot angle, thereby control the heating power of synthetic piece.The persevering average voltage of regulative mode, permanent effective voltage, permanent average current, permanent effective current and five kinds of modes of permanent power.The general analog or digital PID control method that adopts.In the practical application, pure analog circuit power regulating eqiupment is still quite general.This control system is simple in structure, and reliable operation is widely used.

But theory analysis and on-the-spot test result show that the control accuracy of the heating power control system of above-mentioned cubic apparatus superhard material hydraulic press is not high, and especially the external power grid voltage pulsation is very big to the influence of heating power control accuracy.Because there are various large power-consuming equipments of working off and in the production scene, voltage ripple of power network even may be up to more than 20%.And the D.C mutual-inductor response speed is slow, accuracy of detection is not high, and signal processing circuit inertia is big, and therefore, the heating control precision of synthetic piece is difficult to guarantee.In addition, synthesizing superhard material product kind is more and more at present, and the assembling mode of synthetic piece is varied, will face different loads with a kind of heating control system, and temperature control precision also is affected.

Synthetic deblocking temperature control accuracy has been considered to influence the primary factor of diamond quality and output.Therefore, need badly and improve cubic apparatus superhard material hydraulic press Power Regulation control system and control method thereof, to improve its control accuracy.

(3) summary of the invention

The objective of the invention is to design a kind of cubic apparatus superhard material hydraulic press Power Regulation control system and control method thereof, real-time accurate detects heating voltage and current signal, change at electrical network timely and effectively heating power is controlled, improve the control accuracy of synthetic piece heating power.

The cubic apparatus superhard material hydraulic press Power Regulation control system of the present invention's design comprises control centre, silicon-controlled voltage regulation device, electric current and voltage detecting circuit, transformer and other relevant circuit.The former limit of transformer through the silicon-controlled voltage regulation device connect AC power, secondary is bonded into piece, control centre of the present invention is a microprocessor, its control port is connected with the silicon-controlled voltage regulation device through photoelectric isolating driving circuit, regulate its pilot angle, the silicon-controlled voltage regulation device is connected in the former limit circuit of synthetic piece heating transformer, the voltage on the former limit of control transformer; The electric current that joins with the former limit of transformer and electric current, the voltage sensor of voltage detecting circuit are respectively Hall current sensor and Hall voltage sensor, the electric current of current detection circuit and voltage detecting circuit, voltage signal output end connect multiplier, insert microprocessor simultaneously, and multiplier inserts microprocessor.Store the production technology data of heating power and time relationship in the microprocessor, also have digital signal processing module, fuzzy control model and proportional plus integral control module.

Microprocessor has the communication interface that links with host computer, and/or analog output interface circuit, and/or the set amount input interface, can with information such as host computer or the direct exchanging control data of other I/O unit, or direct input power setting value.

The control method of the cubic apparatus superhard material hydraulic press Power Regulation control system of the present invention's design is as follows:

Electric current and voltage detecting circuit are surveyed the instantaneous value of the current/voltage on the former limit of transformer and are sent into microprocessor and multiplier, by the product of four-quadrant analog multiplier calculating voltage and electric current, the instantaneous value of acquisition heating power, the instantaneous value of heating power is also sent into microprocessor processes.Precision and the real-time that has guaranteed heating current, voltage and power calculated in measurement of the present invention.

The signal processing module of microprocessor is to the instantaneous value rectification of heating current, voltage and power, carry out mean filter then, obtain the rectification average, the conversion relation of virtual value routinely and average obtains the virtual value of current accurately heating current, heating voltage again.This signal processing method effectively reduces the inertia and the hysteresis of traditional measurement method, has improved the real-time of signal, helps improving the dynamic characteristic of control system.Particularly this average heating power measuring method has guaranteed the certainty of measurement of effective heating power.

The signal processing module of microprocessor calculates current set-point poor of above-mentioned gained heating power mean value and heating power, obtains error e, again e is carried out differential calculation, obtains error rate ec.

The fuzzy control model of microprocessor stores the fuzzy control rule of regulating the proportional integral parameter.The fuzzy control model of microprocessor is an input variable with error e and error rate ec, asks for proportionality coefficient K by fuzzy control rule _P0With integral coefficient K _I0Online correction amount K _P, Δ K _IWith gained Δ K _P, Δ K _ITo K _P0And K _I0Carry out online correction, correction result is current K _PAnd K _IWith current K _PAnd K _ISend into next moment SCR control angle of proportional plus integral control module accurate Calculation, microprocessor is sent into high-power silicon controlled rectifier pressure regulator with the pilot angle signal through photoelectric isolating driving circuit by output port, it is carried out phase shift triggers, the voltage on the former limit of control heating transformer obtains stable low-voltage, high-current heating power at the transformer secondary.

Microprocessor has RS232 communication interface and set amount input interface, analog output interface circuit, is connected with host computer and/or other I/O unit, effectively gets in touch with, manages and control.

The advantage of cubic apparatus superhard material hydraulic press Power Regulation control system of the present invention and control method thereof is: the Hall element that 1, has adopted accurate measurement electric weight, and the signal processing method that converts of the mean filter of very little alternation of inertia lag and average virtual value, make the signal that is obtained can reflect the variation of line voltage preferably in real time; 2, fuzzy control model carries out the fuzzy control adjusting according to the parameter of statistical value Comparative Examples integral controller, tackle the variation of line voltage in time by real-time heating power signal, voltage to the former limit of transformer is controlled in real time, reach the setting value of heating power, and overshoot can not appear, effectively improve the quality of synthesizing superhard material synthetic diamond single crystal and composite sheet thereof (PDC); 3, native system provides the good communication interface, and host computer can be set the heating power parameter of microprocessor according to actual conditions, is convenient to make up the cubic apparatus superhard material hydraulic press system that adaptability is strong, integration is high.

(4) description of drawings

Fig. 1 is this cubic apparatus superhard material hydraulic press Power Regulation control system embodiment electrical block diagram; The figure internal label is:

AC power 1, silicon-controlled voltage regulation device 2, transformer 3, synthetic piece 4, multiplier 5, microprocessor 6;

Fig. 2 is the fuzzy control model structural representation of this cubic apparatus superhard material hydraulic press Power Regulation control system embodiment;

Fig. 3 is the control method embodiment of this cubic apparatus superhard material hydraulic press Power Regulation control system and the heating power response curve comparison diagram of common pid Power Regulation control system.Among the figure, 2. being the heating power response curve of present embodiment, 1. is the heating power response curve of conventional PID control;

Fig. 4 is the control method flow chart of this cubic apparatus superhard material hydraulic press Power Regulation control system embodiment.

(5) specific embodiment

This cubic apparatus superhard material hydraulic press Power Regulation control system embodiment circuit structure as shown in Figure 1, heating transformer 3 secondary are bonded into piece 4, silicon-controlled voltage regulation device 2 is connected in the circuit of the former limit of heating transformer 3 and AC power 1, the current detection circuit and the voltage detecting circuit that are connected to Hall current sensor and Hall voltage sensor respectively are connected on the transformer 3 former limit circuit, its output signal inserts multiplier 5, and inserts microprocessor 6 as control centre with the output of multiplier 5.Microprocessor 6 joins through photoelectric isolating circuit and silicon-controlled voltage regulation device 2.Store the process data that heating power and time relationship are set in the microprocessor 6, also have signal processing module, fuzzy control model and proportional plus integral control module.

Microprocessor 6 is furnished with RS232 communication interface and analog output interface circuit, set amount input interface, for linking with host computer and/or other I/O unit, effectively gets in touch with, manages and control.

As shown in Figure 2, the schematic diagram that is connected with signal processing module, proportional plus integral control module for the fuzzy control model of microprocessor 6 (be called for short FLC, be Mamdani pattern fuzzy logic controller).Store the fuzzy control rule of regulating proportional integral parameter correction in the fuzzy control model.

The control method flow chart of cubic apparatus superhard material hydraulic press Power Regulation control system embodiment of the present invention as shown in Figure 4.

Beginning heating transformer 3 is controlled when this control system receives instruction, promptly is T with the zero hour ₀, with the heating power of microprocessor 6 storages and the T of time relationship setting ₀Corresponding.

Microprocessor 6 is by carrying out n primary current and voltage sample in the setting-up time cycle t, t=10ms, n=150～400.In this example t=10ms, n=200, it is per 0.05 millisecond of once sampling, the heating current on electric current and transformer that voltage detecting circuit is surveyed 3 former limits, the instantaneous value of voltage are sent into microprocessor 6, the heating power instantaneous value that multiplier 5 calculates is also sent into microprocessor 6, and the signal processing module of microprocessor 6 is to the instantaneous value filtering of electric current I, voltage V and power P.The sampled data sequential storage is one-period with n=200, and promptly 10ms asks for mean value one time:

Average current: $\stackrel{-}{I}=\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{I}_j\right)/n,$

Average voltage: $\stackrel{-}{V}=\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{V}_j\right)/n,$

Mean power: $\stackrel{-}{P}=\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{P}_j\right)/n,$

Wherein, I _j, V _j, P _jBe respectively the j time sampled value of electric current, voltage and power.

Microprocessor 6 obtains heating current, voltage and heating power mean value by aforementioned calculation, and the conversion relation of virtual value and average calculates routinely again, obtains heating current virtual value, heating voltage virtual value.Therefore, native system can be established electric current, voltage and three kinds of control models of power, and the user can select wherein a kind of as required, and system default is a power control mode.

The signal processing module of microprocessor 6 reads current heating power set-point.Selected to read current heating power setting value according to the current time by the heating power of microprocessor 6 storage inside and the process data of time coupling by system, perhaps the input interface by microprocessor 6 reads the current heating power setting value that host computer provides.Ask for its poor with actual heating power mean value according to current heating power setting value, obtain error e, again e is carried out differential calculation, acquisition error rate ec.The fuzzy control model of microprocessor 6 is an input variable with error e and error rate ec, asks for proportionality coefficient K by fuzzy control rule _P0With integral coefficient K _I0Current correction amount K _P, Δ K _I

The preparation method of described fuzzy control rule is as follows:

Obtain system heating power setting value and the error e of heating power mean value and the correction value Δ K of error rate ec and proportional gain factor sometime according to emulation experiment and production practices _PWith integral coefficient correction value Δ K _IThe relativeness statistical value, obtain the fuzzy control rule of corresponding relation between them through normalization conversion and Fuzzy processing

ΔK _P＝f(e，ec)

ΔK _I＝f’(e，ec)

Be stored in the fuzzy control model of microprocessor 6.

With the current Δ K of gained _P, Δ K _ITo K _P0And K _I0Carry out online correction,

K _P＝K _P0+ΔK _P，

K _I＝K _I0+ΔK _I。

With revised K _PAnd K _ISend into next moment SCR control angle of proportional plus integral control module accurate Calculation, microprocessor 6 is sent into high-power silicon controlled rectifier pressure regulator 2 with the pilot angle signal through photoelectric isolating circuit by output interface, carrying out phase shift triggers, the voltage on control transformer 3 former limits obtains stable low-voltage, high-current heating power at transformer 3 secondary.

The RS232 communication interface of microprocessor 6 is connected with host computer, and host computer receives heating current, voltage and the performance number of native system in real time, and set to regulate the process data that heating power that native system microprocessor 6 stored and time mates according to actual conditions.Also can directly import data from the set amount input interface and regulate the process data that heating power that microprocessor 6 stored and time mates by other input block.

Figure 3 shows that when supply voltage is the sinusoidal voltage of ± 20% changes in amplitude, this cubic apparatus superhard material hydraulic press Power Regulation control system embodiment and the control effect contrast figure of conventional PID Power Regulation control system in 2 second time, wherein 2. curve is depicted as present embodiment heating power response curve, and 1. curve is the heating power response curve of conventional PID Power Regulation control system.The heating power fluctuation of the control system of present embodiment is less than 0.05kW, and the fluctuation up 0.8kW of conventional PID Power Regulation control system heating power.As seen stability improves greatly.

Native system can be selected to determine current heating power setting value by the heating power of microprocessor 6 storage inside and time relationship process data, perhaps read the current heating power setting value that host computer gives by microprocessor 6 input interfaces, perhaps other input block is directly imported current heating power setting value by microprocessor 6 set amount input interfaces.

Claims (9)

1. cubic apparatus superhard material hydraulic press Power Regulation control system, comprise control centre, silicon-controlled voltage regulation device and current detection circuit and voltage detecting circuit, the former limit of transformer (3) connects AC power (1) through connecing silicon-controlled voltage regulation device (2), secondary is bonded into piece (4), the holding wire of control centre is connected, controls the SCR control angle with silicon-controlled voltage regulation device (2), the signal of the current/voltage testing circuit that joins with the former limit of transformer (3) is sent into control centre, it is characterized in that:

Described control centre is microprocessor (6), microprocessor (6) joins through photoelectric isolating circuit and silicon-controlled voltage regulation device (2), the electric current that described current detection circuit and voltage detecting circuit connect, voltage sensor are Hall current sensor and Hall voltage sensor, the electric current of current detection circuit and voltage detecting circuit, voltage signal output end connect multiplier (5), insert microprocessor (6) simultaneously, and multiplier (5) inserts microprocessor (6); Store the process data of heating power and time relationship in the microprocessor (6), also have signal processing module, fuzzy control model and proportional plus integral control module.

2. cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 1 is characterized in that:

The fuzzy control model of described microprocessor (6) stores the fuzzy control rule of regulating proportional integral parameter correction.

3. cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 1 and 2 is characterized in that:

Described microprocessor (6) is furnished with the RS232 communication interface, and/or analog output interface circuit, and/or the set amount input interface.

4. the control method of cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 1 and 2 is characterized in that:

The instantaneous value of the current/voltage on the former limit of described current detection circuit and transformer that voltage detecting circuit is surveyed (3) is sent into microprocessor (6) and multiplier (5), and the instantaneous value that is obtained heating power by the product of multiplier (5) calculating voltage and electric current is also sent into microprocessor (6);

The signal processing module of microprocessor (6) is to the instantaneous value rectification of heating current, voltage and power, carry out mean filter then, obtain the rectification average, the conversion relation of virtual value routinely and average obtains current accurately heating current, heating voltage virtual value and heating power mean value again; The signal processing module of microprocessor (6) calculates current set-point poor of above-mentioned gained heating power mean value and heating power, obtains error e, again e is carried out differential calculation, obtains error rate ec; The fuzzy control model of microprocessor (6) is an input variable with error e and error rate ec, asks for proportionality coefficient K by fuzzy control rule _P0With integral coefficient K _I0Online correction amount K _P, Δ K _I, with the current Δ K of gained _P, Δ K _ITo K _P0And K _I0Carry out online correction,

K _P＝K _P0+ΔK _P，

K _I＝K _I0+ΔK _I；

With current K _PAnd K _ISend into next moment silicon controlled pilot angle of proportional plus integral control module accurate Calculation, microprocessor (6) is sent into high-power silicon controlled rectifier pressure regulator (2) with the pilot angle signal through photoelectric isolating circuit by output port, it is carried out phase shift triggers, the voltage on the former limit of control transformer (3) obtains stable low-voltage, high-current heating power at transformer (3) secondary.

5. the control method of cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 4 is characterized in that the preparation method of described fuzzy control rule is as follows:

Obtain system heating power setting value and the error e of heating power mean value and the correction value Δ K of error rate ec and proportional gain factor sometime according to emulation experiment and production practices _PWith integral coefficient correction value Δ K _IThe relativeness statistical value, obtain the fuzzy control rule of corresponding relation between them through normalization conversion and Fuzzy processing

ΔK _P＝f(e，ec)

ΔK _I＝f’(e，ec)。

6. according to the control method of claim 4 or 5 described cubic apparatus superhard material hydraulic press Power Regulation control systems, it is characterized in that:

The RS232 communication interface of microprocessor (6) is connected with host computer, host computer receives heating current, voltage and the performance number of native system in real time, and set to regulate the process data that heating power that native system microprocessors (6) are stored and time mates according to actual conditions; Perhaps other input block is regulated the process data that heating power that microprocessors (6) are stored and time mates by set amount input interface input data.

7. the control method of cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 6 is characterized in that:

Select to read current heating power setting value by the heating power of microprocessor (6) storage inside and the process data of time coupling by system according to the current time, perhaps the input interface by microprocessor (6) reads the current heating power setting value that host computer provides, and perhaps other input block is directly imported current heating power setting value by microprocessor (6) set amount input interface.

8. the control method of cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 4 is characterized in that:

Microprocessor (6) is by carrying out n primary current and voltage sample in the setting-up time cycle t, the signal processing module that the power instantaneous value that the electric current on the former limit of institute's survey transformer (3), the instantaneous value of voltage and multiplier (5) calculate is sent into microprocessor (6) carries out filtering, the sampled data sequential storage, with n is one-period, ask for a mean value of electric current, voltage and power

$\stackrel{-}{I}=\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{I}_j\right)/n,$

$\stackrel{-}{V}=\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{V}_j\right)/n,$

$\stackrel{-}{P}=\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{P}_j\right)/n.$

9. the control method of cubic apparatus superhard material hydraulic press Power Regulation control system according to claim 8 is characterized in that:

Described time t=10ms, n=150～400.

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