CN203477541U - Gas proportional valve PWM (Pulse-Width Modulation) drive circuit - Google Patents
Gas proportional valve PWM (Pulse-Width Modulation) drive circuit Download PDFInfo
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- CN203477541U CN203477541U CN201320430745.2U CN201320430745U CN203477541U CN 203477541 U CN203477541 U CN 203477541U CN 201320430745 U CN201320430745 U CN 201320430745U CN 203477541 U CN203477541 U CN 203477541U
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Abstract
The utility model discloses a gas proportional valve PWM (Pulse-Width Modulation) drive circuit which is widely applied to fields of gas water heaters, gas-fired hot water boilers and the like. The circuit comprises a PWM signal conversion circuit consisting of an operational amplifier IC (Integrated Circuit) U1 and a peripheral circuit, a follow feedback circuit consisting of an operational amplifier IC U2 and another peripheral circuit, and a valve drive circuit consisting of triodes Q1 and Q2 and another peripheral circuit. When the circuit is used, a PWM signal is converted into a corresponding analog voltage through the operational amplifier IC U1 and the peripheral circuit, the voltage is transmitted to the follow feedback circuit consisting of the operational amplifier IC U2 and the peripheral circuit, in the follow feedback circuit, the voltage is compared with a sampling voltage fed back through a proportional valve so as to output an appropriate opening voltage, and the opening voltage is used for controlling the drive circuit consisting of the triodes Q1 and Q2 and the peripheral circuit so as to drive the proportional valve. Due to the adoption of hardware control, the drive circuit is fast in operation speed, high in control precision, stable in control on the proportional valve and completely free of phenomena of shaking and the like, and moreover the power triode Q2 is very low in internal power consumption, so that the drive circuit is a significant device for constant temperature control on products such as gas water heaters and gas-fired hot water boilers.
Description
Technical field
The present invention relates to a kind of gas ratio valve PWM drive circuit, especially a kind of Proportional valve drive circuit that is applied to gas water-heater, gas-fired water heating boiler and some high-end thermostatic control technology products.
Background technique
Currently available technology, at products such as gas water-heater, gas heating boilers, especially, in its high-end automatic constant-temperature control type product, is used gas ratio valve general already.This series products has adopted relevant automatic control technology to the thermostatically control of Gas Load adjusting and health hot water and heating water, and control mode is varied, as PID control, fuzzy control, Self-learning control etc.In this class thermostatic control technology, all can't do without usining Proportional valve as the controlling unit of actuator, and the driving of comparative example valve to control be all also almost pwm pattern.Therefore to control be also unusual the key link in whole system control technique in the driving of Proportional valve.
In the products such as existing automatic constant-temperature control type gas water-heater, gas heating boiler, what the PWM of comparative example valve drove employing mostly is more easy switching mode control mode, its hardware circuit is fairly simple, nearly all just with pwm signal, comes direct control ratio valve to drive the on off state of triode to realize the modulation of comparative example valve operating voltage completely.This PWM modulation control relies on software to realize mostly completely, and the monitoring of comparative example threshold voltage is also that comparative example threshold voltage carries out by software, being undertaken after reverse feedback is relatively calculated pwm signal to carry out correcting process again after AD sampling.Yet, in the thermostatically control algorithm of system, and even the correction adjustment of pwm signal is often subject to again coming from the differential of temperature difference temperature variation, the impact of the output action of integration scheduling algorithm result, thereby the PWM of comparative example valve modulation regulates and control that not only process is complicated, and control rate and control accuracy are all had a greatly reduced quality.Optimal way is to rely on one independently to move the driving that module is implemented comparative example valve after system pwm signal is outputed to Proportional valve drive circuit, this module can directly complete separately comparative example valve and drive, and by its independently degeneration factor realize fast from adjusting, to guarantee that Proportional valve is fast, accurately, stably carry out its operating voltage adjustment with target P WM signal.
Summary of the invention
The object of the invention is: be to solve the difficult problem generally running into while carrying out thermostatically control design in the products such as automatic constant-temperature control type gas water-heater, gas heating boiler, provide one can independent operating Proportional valve drive control module, comparative example valve can be realized accurately fast from adjusting and controlling, to reduce the complexity of thermostatically control software algorithm, and improve a kind of gas ratio valve PWM drive circuit of system thermostatically control precision and speed.
The present invention is achieved in that a kind of gas ratio valve PWM drive circuit, it comprises the pwm signal change-over circuit being comprised of the first operational amplifier IC circuit and peripheral circuit, the second operational amplifier IC circuit and peripheral circuit form follows feeder loop, three parts such as valve-driving circuit that the first triode, the second triode and peripheral circuit thereof form;
Pwm signal change-over circuit with follow feeder loop and be connected, follow feeder loop and be connected with valve-driving circuit.
Described a kind of gas ratio valve PWM drive circuit, its special way is: described pwm signal change-over circuit is comprised of the first operational amplifier IC circuit U 1 and peripheral circuit the first resistance R 1 thereof, the second resistance R 2, the 3rd resistance R 3, the first capacitor C 1, the second capacitor C 2; First resistance R 1 one end is as pwm signal input interface, the other end accesses the common mode inlet opening of the first operational amplifier IC circuit U 1 with the first capacitor C 1 positive pole, the second resistance R 2 after being connected in parallel, the first capacitor C 1 negative pole, second resistance R 2 the other ends are all connected with circuitry ground; The difference-mode input mouth of the first operational amplifier IC circuit U 1 is directly connected with its output terminal, then through output terminal, connects with the 3rd resistance R 3; The 3rd resistance R 3 the other ends and the second capacitor C 2 common mode inlet opening anodal and the second operational amplifier IC circuit U 2 are in parallel, and the second capacitor C 2 negative poles are connected with circuitry ground;
The described feeder loop of following is comprised of the second operational amplifier IC circuit U 2 and peripheral circuit the 4th resistance R 4, the 8th resistance R 8, the 9th resistance R 9, the 3rd capacitor C 3; The second common mode inlet opening of operational amplifier IC circuit U 2 and the output terminal of described pwm signal change-over circuit are also that the points of common connection of the 3rd resistance R 3, the second capacitor C 2 is connected, and its difference-mode input mouth is connected with the points of common connection of the 4th resistance R 4, the 3rd capacitor C 3, the 8th resistance R 8; The 4th resistance R 4 the other end welding system power vd D are anodal, the 3rd capacitor C 3 another utmost point connection circuits systematically, the 8th resistance R 8 the other ends are connected with the 9th resistance R 9 of feedback sample resistance and the negative pole interface of Proportional valve, and the 9th resistance R 9 the other end put in circuit systematically; The output terminal of the second operational amplifier IC circuit U 2 is connected with base resistance the 5th resistance R 5 of the first triode Q1 in valve-driving circuit;
Described first, second triode of electrohydraulic valve actuator route Q1, Q2 and peripheral circuit the 5th resistance R 5 thereof, the 6th resistance R 6, the 7th resistance R 7, the first diode D1 form, one end of the base resistance of the first triode Q1 the 5th resistance R 5 is connected with the output terminal of following the second operational amplifier IC circuit U 2 in feeder loop, and the other end of the 5th resistance R 5 is connected with the base stage of the first triode Q1; The emitter of the first triode Q1 is directly connected with circuitry ground, its collector electrode is connected with base resistance the 6th resistance R 6 of pliotron the second triode Q2, the 6th resistance R 6 the other ends are connected with base stage and pull-up resistor the 7th resistance R 7 of the second triode Q2, and the emitter access Proportional valve working power VCC of the other end of the 7th resistance R 7 and the second triode Q2 is anodal; The second collector electrode of triode Q2 and the anode interface of Proportional valve are connected, the first diode D1 is as the reversal protection diode of Proportional valve, it is together with Proportional valve reverse parallel connection, and its negative pole is connected with the anode interface of Proportional valve, anodal be connected with the negative pole interface of Proportional valve; The negative pole interface of Proportional valve with follow the 8th resistance R 8 in feeder loop and feedback sample resistance the 9th resistance R 9 mutually and connect;
In described circuit, the negative pole of system power supply VDD, Proportional valve working power VCC is all connected with circuitry ground; In described first, second circuit, operational amplifier IC circuit is all operated under system power supply VDD, be to be also connected with system power supply VDD is anodal described in its positive source, described in power cathode with circuitry be connected.
Described a kind of gas ratio valve PWM drive circuit, its special way is: the first triode Q1 is NPN type pipe, and the second triode Q2 is positive-negative-positive.
Described a kind of gas ratio valve PWM drive circuit, its special way is: the resistance of the first resistance R 1 is less than the resistance of the second resistance R 2.
A kind of gas ratio valve PWM drive circuit, during circuit working, pwm signal converts corresponding analog voltage to through operational amplifier IC circuit U 1 and peripheral circuit, inputing to operational amplifier IC circuit U 2 and peripheral circuit forms and follows feeder loop, at this voltage in following feeder loop through exporting suitable aperture voltage with Proportional valve feedback sample voltage ratio after, the drive circuit that this aperture Control of Voltage triode Q1, Q2 and peripheral circuit thereof form, comparative example valve drives.Because this drive circuit adopts hardware controls completely, motion speed is fast, control accuracy is high, comparative example valve is controlled steadily, the phenomenons such as complete non-jitter, therefore and pliotron Q2 internal power consumption is extremely low, be very important means during thermostatically control in the products such as gas water-heater, gas-fired water heating boiler.
Accompanying drawing explanation
Fig. 1 is circuit diagram of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described.
As shown in Figure 1, a kind of gas ratio valve PWM drive circuit, it mainly comprises the pwm signal change-over circuit that the first calculation amplifier IC circuit U 1 and peripheral circuit form, the second operational amplifier IC circuit U 2 and peripheral circuit form follows feeder loop, three parts such as valve-driving circuit that first, second triode Q1, Q2 and peripheral circuit thereof form.
As shown in Figure 1, described pwm signal change-over circuit is comprised of the first operational amplifier IC circuit U 1 and peripheral circuit the first resistance R 1 thereof, the second resistance R 2, the 3rd resistance R 3, the first capacitor C 1, the second capacitor C 2.First resistance R 1 one end is as pwm signal input interface, the other end accesses the common mode inlet opening of the first operational amplifier IC circuit U 1 with the first capacitor C 1 positive pole, the second resistance R 2 after being connected in parallel, the first capacitor C 1 negative pole, second resistance R 2 the other ends are all connected with circuitry ground.The difference-mode input mouth of the first operational amplifier IC circuit U 1 is directly connected with its output terminal, then through output terminal, connects with the 3rd resistance R 3.The 3rd resistance R 3 the other ends and the second capacitor C 2 common mode inlet opening anodal and the second operational amplifier IC circuit U 2 are in parallel, and the second capacitor C 2 negative poles are connected with circuitry ground.
As shown in Figure 1, described in, following feeder loop is comprised of the second operational amplifier IC circuit U 2 and peripheral circuit the 4th resistance R 4, the 8th resistance R 8, the 9th resistance R 9, the 3rd capacitor C 3.The common mode inlet opening of the second operational amplifier IC circuit U 2 is connected with the output terminal of described pwm signal change-over circuit, is connected with the points of common connection of the 3rd resistance R 3, the second capacitor C 2; Its difference-mode input mouth is connected with the points of common connection of the 4th resistance R 4, the 3rd capacitor C 3, the 8th resistance R 8.The 4th resistance R 4 the other end welding system power vd D are anodal, the 3rd capacitor C 3 another utmost point connection circuits systematically, through eight resistance R 8 the other ends, be connected with the negative pole interface of feedback sample resistance the 9th resistance R 9 and Proportional valve, the 9th resistance R 9 the other end put in circuit systematically.The output terminal of the circuit U 2 of the second operational amplifier IC is connected with base resistance the 5th resistance R 5 of the first triode Q1 in valve-driving circuit.
As shown in Figure 1, described first, second triode of electrohydraulic valve actuator route Q1, Q2 and peripheral circuit the 5th resistance R 5 thereof, the 6th resistance R 6, the 7th resistance R 7, the first diode D1 form, wherein the first triode Q1 is NPN type pipe, and the second triode Q2 is positive-negative-positive pliotron.One end of the base resistance of the first triode Q1 the 5th resistance R 5 is connected with the output terminal of following the second operational amplifier IC circuit U 2 in feeder loop, and the other end of the 5th resistance R 5 is connected with the base stage of the first triode Q1.The first triode Q1 emitter is directly connected with circuitry ground, its collector electrode is connected with base resistance the 6th resistance R 6 of pliotron the second triode Q2, the 6th resistance R 6 the other ends are connected with the base stage of the second triode Q2 and the 7th resistance R 7 of pull-up resistor, and the emitter access Proportional valve working power VCC of the other end of the 7th resistance R 7 and the second triode Q2 is anodal.The second collector electrode of triode Q2 and the anode interface of Proportional valve are connected; the first diode D1 is as the reversal protection diode of Proportional valve; it is together with Proportional valve reverse parallel connection, and its negative pole is connected with the anode interface of Proportional valve, anodal be connected with the negative pole interface of Proportional valve.The negative pole interface of Proportional valve with follow the 8th resistance 8 in feeder loop and feedback sample resistance the 9th resistance R 9 mutually and connect.
As shown in Figure 1, in described circuit, the negative pole of system power supply VDD, Proportional valve working power VCC is all connected with circuitry ground.In described circuit, first, second operational amplifier IC circuit U 1, U2 are all operated under system power supply VDD, be to be also connected with system power supply VDD is anodal described in its positive source, described in power cathode with circuitry be connected.
As shown in Figure 1, during circuit working, pwm signal is through the first resistance R 1, the second resistance R 2 dividing potential drops, after the first capacitor C 1 filtering, convert again the corresponding analog voltage signal of a little ripple to, what through the first operational amplifier IC circuit U 1, form follows after shaping circuit again, the comparatively stable analog voltage of output terminal output in the first operational amplifier IC circuit U 1, and then through the 3rd resistance R 3, the further voltage stabilizing of the second capacitor C 2, finally output to the common mode input end of the second operational amplifier IC circuit U 2.
Work when initial, the driving triode second triode Q2 of Proportional valve is in closed condition, therefore Proportional valve operating voltage is zero, thereby feedback resistance the 9th resistance R 9 two ends resistance are also zero, therefore the voltage of the common mode input end of the second operational amplifier IC circuit U 2 is also zero, now the output end voltage of the second operational amplifier IC circuit U 2 is VDD, this voltage is input to the base stage through a triode Q1 through the 5th resistance R 5, the first triode Q1 opens, corresponding the 6th resistance R 6 of passing through, pliotron the second triode Q2 produces base current and leaks into systematically, thereby second triode Q2 be also opened, therefore Proportional valve supply voltage VCC is applied in Proportional valve and feedback resistance the 9th resistance R 9.Feedback voltage in feedback resistance the 9th resistance R 9 through the 8th resistance R 8, the 3rd capacitor C 3 filtering voltage regulations and after the clamped effect of the 4th resistance R 4 feed back input to the difference-mode input end of the second operational amplifier IC circuit U 2.The second operational amplifier IC circuit U 2 common mode terminal voltages and difference-mode input terminal voltage compare, and when the former is greater than the latter, it continues output high pressure VDD, otherwise output no-voltage.So repeatedly, until the second operational amplifier IC circuit U 2 common mode terminal voltages and difference-mode input terminal voltage difference be close to zero.Like this, the second operational amplifier IC circuit U 2 and peripheral circuit thereof have formed a set of complete reverse feedback voltage follower circuit in fact, allowing the feedback voltage of Proportional valve tightly follow the voltage of the first operational amplifier IC circuit U 2 common mode input ends, is also the desired target voltage of pwm signal.The operating voltage that has guaranteed like this Proportional valve changes and changes with regard to tightly following the desired target voltage of pwm signal.
When circuit is implemented, the parameter of components and parts is selected most important, one, the selection of divider resistance the first resistance R 1, the second resistance R 2, general the two value equates or R1≤R2, with the pwm signal amplitude that guarantees minute to press out in 0.5VDD, thereby the first operational amplifier IC circuit U 1 follow voltage range in its low side voltage zone, make the operating accuracy of the first operational amplifier IC circuit U 1 higher.Next is choosing of feedback the 9th resistance R 9 sizes, and this resistance value will be selected according to pwm signal scope, the first resistance R 1 and second value of resistance R 2 and the operating voltage range of Proportional valve.Generally speaking, resistance value+induction reactance value of Proportional valve is 82～100 Ω (getting intermediate value 90), the operating voltage of Proportional valve is VCC, the common mode input end analog voltage that guarantees the second operational amplifier IC circuit U 2 when the value of the first resistance R 1 and the second resistance R 2 is at 0.5VDD during with interior variation, R9=0.5VDD * 90/ (VCC-0.5VDD-0.2), wherein 0.2 is the Vce minimum tube pressure drop of triode Q2.Work as VDD=5V, during VCC=24V, R9 ≈ 10 Ω.
Above-described is only preferential mode of execution of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the principles of the present invention, can also make some improvement and modification, this is also considered as protection scope of the present invention.
Claims (4)
1. a gas ratio valve PWM drive circuit, it is characterized in that: it comprises the pwm signal change-over circuit being comprised of the first operational amplifier IC circuit (U1) and peripheral circuit, the second operational amplifier IC circuit (U2) and peripheral circuit form follows feeder loop, three parts such as valve-driving circuit that the first triode (Q1), the second triode (Q2) and peripheral circuit thereof form;
Pwm signal change-over circuit with follow feeder loop and be connected, follow feeder loop and be connected with valve-driving circuit.
2. a kind of gas ratio valve PWM drive circuit according to claim 1, is characterized in that: described pwm signal change-over circuit is comprised of the first operational amplifier IC circuit (U1) and peripheral circuit the first resistance (R1) thereof, the second resistance (R2), the 3rd resistance (R3), the first electric capacity (C1), the second electric capacity (C2); The first resistance (R1) one end is as pwm signal input interface, the other end, second resistance (R2) anodal with the first electric capacity (C1) accesses the common mode inlet opening of the first operational amplifier IC circuit (U1) after being connected in parallel, the first electric capacity (C1) negative pole, the second resistance (R2) the other end are all connected with circuitry ground; The difference-mode input mouth of the first operational amplifier IC circuit (U1) is directly connected with its output terminal, then through output terminal, connects with the 3rd resistance (R3); The 3rd resistance (R3) the other end and the second electric capacity (C2) common mode inlet opening anodal and the second operational amplifier IC circuit (U2) is in parallel, and the second electric capacity (C2) negative pole is connected with circuitry ground;
The described feeder loop of following is comprised of the second operational amplifier IC circuit (U2) and peripheral circuit the 4th resistance (R4), the 8th resistance (R8), the 9th resistance (R9), the 3rd electric capacity (C3); The second common mode inlet opening of operational amplifier IC circuit (U2) and the output terminal of described pwm signal change-over circuit are also that the points of common connection of the 3rd resistance (R3), the second electric capacity (C2) is connected, and its difference-mode input mouth is connected with the points of common connection of the 4th resistance (R4), the 3rd electric capacity (C3), the 8th resistance (R8); The 4th resistance (R4) the other end welding system power vd D is anodal, the 3rd another utmost point connection circuit of electric capacity (C3) systematically, the 8th resistance (R8) the other end is connected with the 9th resistance (R9) of feedback sample resistance and the negative pole interface of Proportional valve, and the 9th resistance (R9) the other end put in circuit systematically; The output terminal of the second operational amplifier IC circuit (U2) is connected with base resistance the 5th resistance (R5) of the first triode (Q1) in valve-driving circuit;
Described first, second triode of electrohydraulic valve actuator route (Q1, Q2) and peripheral circuit the 5th resistance (R5) thereof, the 6th resistance (R6), the 7th resistance (R7), the first diode (D1) form, one end of base resistance the 5th resistance (R5) of the first triode (Q1) is connected with the output terminal of following the second operational amplifier IC circuit (U2) in feeder loop, and the other end of the 5th resistance (R5) is connected with the base stage of the first triode (Q1); The first triode (Q1) emitter is directly connected with circuitry ground, its collector electrode is connected with base resistance the 6th resistance (R6) of pliotron the second triode (Q2), the 6th resistance (R6) the other end is connected with base stage and pull-up resistor the 7th resistance (R7) of the second triode (Q2), and the emitter access Proportional valve working power VCC of the other end of the 7th resistance (R7) and the second triode (Q2) is anodal; The collector electrode of the second triode (Q2) is connected with the anode interface of Proportional valve, the first diode (D1) is as the reversal protection diode of Proportional valve, it is together with Proportional valve reverse parallel connection, and its negative pole is connected with the anode interface of Proportional valve, anodal be connected with the negative pole interface of Proportional valve; The negative pole interface of Proportional valve with follow the 8th resistance 8 in feeder loop and feedback sample resistance the 9th resistance (R9) mutually and connect;
In described circuit, the negative pole of system power supply VDD, Proportional valve working power VCC is all connected with circuitry ground; In described first, second circuit, operational amplifier IC circuit (U1, U2) is all operated under system power supply VDD.
3. a kind of gas ratio valve PWM drive circuit according to claim 1, is characterized in that: the first triode (Q1) is NPN type pipe, and the second triode (Q2) is positive-negative-positive.
4. a kind of gas ratio valve PWM drive circuit according to claim 2, is characterized in that: the resistance of the first resistance (R1) is less than or equal to the resistance of the second resistance (R2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320430745.2U CN203477541U (en) | 2013-07-19 | 2013-07-19 | Gas proportional valve PWM (Pulse-Width Modulation) drive circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320430745.2U CN203477541U (en) | 2013-07-19 | 2013-07-19 | Gas proportional valve PWM (Pulse-Width Modulation) drive circuit |
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| Publication Number | Publication Date |
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| CN203477541U true CN203477541U (en) | 2014-03-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320430745.2U Withdrawn - After Issue CN203477541U (en) | 2013-07-19 | 2013-07-19 | Gas proportional valve PWM (Pulse-Width Modulation) drive circuit |
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| CN (1) | CN203477541U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103411010B (en) * | 2013-07-19 | 2015-12-23 | 佛山市顺德区希骏电子有限公司 | A kind of gas ratio valve PWM drive circuit |
| CN112066564A (en) * | 2020-09-15 | 2020-12-11 | 重庆海尔热水器有限公司 | Gas water heater and control circuit of proportional valve thereof |
-
2013
- 2013-07-19 CN CN201320430745.2U patent/CN203477541U/en not_active Withdrawn - After Issue
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103411010B (en) * | 2013-07-19 | 2015-12-23 | 佛山市顺德区希骏电子有限公司 | A kind of gas ratio valve PWM drive circuit |
| CN112066564A (en) * | 2020-09-15 | 2020-12-11 | 重庆海尔热水器有限公司 | Gas water heater and control circuit of proportional valve thereof |
| CN112066564B (en) * | 2020-09-15 | 2022-01-18 | 重庆海尔热水器有限公司 | Gas water heater and control circuit of proportional valve thereof |
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Granted publication date: 20140312 Effective date of abandoning: 20151223 |
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| AV01 | Patent right actively abandoned |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |