Gas water heater, proportional valve control device and control method thereof

Abstract

The present invention discloses a gas water heater, a proportional valve control device and a control method thereof. The proportional valve control device includes: a main control device for outputting a proportional valve drive signal and a deadband compensation signal; and a proportional valve drive circuit for controlling the opening degree of the proportional valve according to the proportional valve drive signal and controlling the proportional valve to generate jitter according to the deadband compensation signal. The proportional valve control method of the present invention can solve the deadband problem of the proportional valve.

Description

Technical Field

[0001] The present invention relates to the technical field of water heaters, and particularly to a gas water heater, a proportional valve control device and a control method thereof. Background Art

[0002] At present, a proportional valve is generally used in a constant-temperature gas water heater to control the amount of gas output from a gas chamber, thereby achieving the effect of controlling the constant temperature of the outlet water. When the proportional valve is in use, since the iron core or coil for controlling the valve size has friction with the valve body wall during movement, the opening degree of the proportional valve will be different from the expected position under the same driving current, that is, the hysteresis problem. The hysteresis problem will reduce the constant-temperature performance of the constant-temperature gas water heater, and the hysteresis value of the secondary pressure will exceed 100 Pa, resulting in potential safety hazards.

[0003] The prior art solves the hysteresis problem of the proportional valve by matching different control frequencies for the driving currents of different types of proportional valves, but it cannot be adapted to all models of proportional valves, and it needs to be correspondingly matched with each model of the proportional valve one by one. Moreover, the circuit matched with each model has problems of complex design, high cost and difficult development. Summary of the Invention

[0004] The main object of the present invention is to provide a proportional valve control method, aiming to solve the hysteresis problem of the proportional valve. To achieve the above object, the present invention proposes a proportional valve control device. The proportional valve control device includes:

[0005] A main control device for outputting a proportional valve drive signal and a hysteresis compensation signal; and

[0006] A proportional valve drive circuit for controlling the opening degree of the proportional valve according to the proportional valve drive signal and controlling the proportional valve to generate jitter according to the hysteresis compensation signal.

[0007] Optionally, the hysteresis compensation signal is a square wave signal, and the main control device further includes:

[0008] A hysteresis signal conversion circuit for converting the hysteresis compensation signal output by the main control device from a square wave signal into a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal.

[0009] Optionally, the hysteresis signal conversion circuit includes:

[0010] An integration circuit for converting the hysteresis compensation signal output by the main control device from a square wave signal into a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal;

[0011] An amplitude adjustment circuit for adjusting the amplitude of the first preset waveform signal to a preset amplitude; and

[0012] A coupling circuit for coupling the amplitude-adjusted first preset waveform signal to the proportional valve drive signal.

[0013] Optionally, the integration circuit includes: an integration resistor and an integration capacitor; the integration resistor has a first end and a second end, the first end of the integration resistor is the input end of the integration circuit for accessing the square wave signal output by the main control device and outputting it from its second end to the first end of the integration capacitor, and the second end of the integration capacitor is grounded; wherein, the second end of the integration resistor and the second end of the integration capacitor are respectively the first output end and the second output end of the integration circuit.

[0014] Optionally, the amplitude adjustment circuit includes: a first amplitude adjustment resistor and a second amplitude adjustment resistor; the first end of the first amplitude adjustment resistor is the first input end of the amplitude adjustment circuit; the first end of the second amplitude adjustment resistor is the second input end of the amplitude adjustment circuit, and the second end of the second amplitude adjustment resistor is connected to the second end of the first amplitude adjustment resistor; the common end of the first amplitude adjustment resistor and the second amplitude adjustment resistor is the output end of the amplitude adjustment circuit.

[0015] Optionally, the coupling circuit includes: a coupling capacitor; the first end of the coupling capacitor is the input end of the coupling circuit, and the second end of the coupling capacitor is the output end of the coupling circuit.

[0016] Optionally, the main control device is further configured to receive a proportional valve control instruction and generate a proportional valve drive signal according to the proportional valve control instruction;

[0017] The main control device is further configured to obtain the frequency of the proportional valve drive signal, perform a multiplication calculation on the frequency and a first preset ratio parameter, and configure the calculation result as the frequency parameter of the deadband compensation signal;

[0018] The main control device is further configured to output a deadband compensation signal of the square wave signal according to a preset duty ratio parameter and the frequency parameter.

[0019] Optionally, the first preset ratio parameter is 10%.

[0020] Optionally, the proportional valve driving circuit includes: a first operational amplifier, a first switching device, a second switching device, a first capacitor, a second capacitor, a third capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor; the first end and the second end of the first resistor are respectively the first input end and the second input end of the proportional valve driving circuit; the positive input end of the first operational amplifier is connected to the first end of the first resistor, its negative input end is connected to the second end of the first resistor through the first capacitor, and the negative input end is also connected to the first end of the eighth resistor through the seventh resistor, and the second end of the eighth resistor is the second output end of the proportional valve driving circuit; the output end of the operational amplifier is grounded through the second resistor and the second capacitor, and the common end of the second resistor and the second capacitor is also connected to a DC voltage input end; the output end of the operational amplifier is also connected to the controlled end of the first switching device through the fourth resistor; the fifth resistor and the sixth resistor are connected in parallel to form a resistor unit; the input end of the first switching device is connected to the input end of the second switching device through the resistor unit, and the output end of the first switching device is connected to the second end of the eighth resistor; the input end of the second switching device is connected to its output end, and the common end of the two is the first output end of the proportional valve driving circuit; the output end of the first operational amplifier is also connected to the second end of the eighth resistor through the third resistor; the output end of the first operational amplifier is also connected to its negative input end through the third capacitor.

[0021] The present invention also provides a proportional valve control method, which includes the following steps:

[0022] Output a proportional valve driving signal and a hysteresis compensation signal, and the hysteresis compensation signal is a square wave signal;

[0023] Convert the hysteresis compensation signal from a square wave signal to a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal; and

[0024] Control the opening degree of the proportional valve according to the proportional valve driving signal and control the proportional valve to generate jitter according to the first preset waveform signal.

[0025] Optionally, the step of converting the hysteresis compensation signal from a square wave signal to a sawtooth wave signal and / or a triangular wave signal includes:

[0026] Convert the hysteresis compensation signal output by the main control device from a square wave signal to a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal;

[0027] Adjust the amplitude of the first preset waveform signal to a preset amplitude; and

[0028] Couple the first preset waveform signal with adjusted amplitude to the proportional valve drive signal.

[0029] Optionally, before performing the step of outputting the proportional valve drive signal and the hysteresis compensation signal, the proportional valve control method further includes the following steps:

[0030] Receive a proportional valve control instruction, and generate a proportional valve drive signal according to the proportional valve control instruction;

[0031] Obtain the frequency of the proportional valve drive signal, perform a multiplication calculation on the frequency and a first preset proportional parameter, and configure the calculation result as the frequency parameter of the hysteresis compensation signal; and

[0032] Output a hysteresis compensation signal of a square wave signal according to a preset duty cycle parameter and the frequency parameter.

[0033] Optionally, the first preset proportional parameter is 10%.

[0034] The present invention also provides a gas water heater, which includes:

[0035] A water heater main body;

[0036] A proportional valve, which is arranged in the water heater main body; and

[0037] It further includes the proportional valve control device as described above, the proportional valve control device is arranged in the water heater main body and is connected to the proportional valve; or, the proportional valve control method as described above is used.

[0038] Optionally, the gas water heater further includes:

[0039] An inlet water pipeline;

[0040] A hot water pipeline, the inlet water pipeline and the hot water pipeline are respectively connected to the water heater main body;

[0041] A first temperature sensor, which is arranged in the inlet water pipeline and is used to detect the inlet water temperature of the inlet water pipeline and output a first temperature detection signal;

[0042] A second temperature sensor, which is arranged in the hot water pipeline and is used to detect the outlet water temperature of the hot water pipeline and output a second temperature detection signal; and

[0043] A temperature adjustment module, which is arranged on the water heater main body, and the temperature adjustment module is used to access a temperature adjustment signal and output it to the proportional valve control device;

[0044] The proportional valve control device is further configured to generate the proportional valve drive signal according to the first temperature detection signal, the second temperature detection signal, and the temperature adjustment signal, so as to perform constant temperature control on the water discharged from the hot water pipeline.

[0045] The proportional valve control device of the present invention controls the opening degree of the proportional valve and makes it jitter by setting a main control device and a proportional valve drive circuit, and the proportional valve drive circuit respectively according to the proportional valve drive signal and the hysteresis compensation signal output by the main control device. By making the iron core of the proportional valve in a jitter state while adjusting the opening degree of the proportional valve, the iron core in the jitter state has less contact with the inner wall of the valve body compared with the iron core in the stable state, and bears less friction when moving to adjust the opening degree of the proportional valve. Therefore, when the same drive current flows through the coil, the opening degree adjustment of the valve body can be made more accurate, thus solving the hysteresis problem of the proportional valve. When the present invention is applied to a constant temperature gas water heater, not only can the constant temperature control be made more accurate, but also the hysteresis value of the secondary pressure in the gas chamber can be greatly reduced to within 15 Pa, greatly improving the safety of the gas chamber. Compared with the existing solutions to the hysteresis problem, there is no need to adjust different models of proportional valves, and the hysteresis compensation signal can be directly superimposed on the original proportional valve drive signal. The adopted circuit structure is simple and easy to implement, which is beneficial to reducing the design cost and development difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0047] Figure 1 It is a schematic diagram of the functional modules of an embodiment of the proportional valve control device of the present invention;

[0048] Figure 2 It is a schematic diagram of the functional modules of another embodiment of the proportional valve control device of the present invention;

[0049] Figure 3 It is a schematic diagram of the circuit structure of another embodiment of the proportional valve control device of the present invention;

[0050] Figure 4 It is a schematic diagram of the flow structure of an embodiment of the proportional valve control device of the present invention;

[0051] Figure 5 It is a schematic diagram of the flow structure of another embodiment of the proportional valve control device of the present invention;

[0052] Figure 6 It is a schematic flowchart structure diagram of another embodiment of the proportional valve control device of the present invention;

[0053] Figure 7 It is a schematic diagram of the functional modules of an embodiment of the gas water heater of the present invention.

[0054] Explanation of the reference numerals in the drawings:

[0055]

[0056]

[0057] The realization of the object, functional features and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0058] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0059] It should be noted that all the directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0060] In the present invention, unless otherwise clearly defined and limited, the terms "connection", "fixation", etc. shall be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0061] In addition, in the present invention, descriptions such as "first" and "second" are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0062] The present invention provides a proportional valve 41 control device.

[0063] The proportional valve 41 may include a valve body, a spring assembly, a coil, and an iron core; the iron core is disposed at an interval from the coil through the valve body, the iron core can be opposite to the valve port, and one end of the iron core opposite to the valve port may be conical. Thus, when no current flows through the coil, the spring assembly uses its own elastic force to block the valve port with the iron core; when current flows through the coil, the coil generates electromagnetic induction to push the iron core in the direction opposite to the elastic force of the spring with magnetic force, so that the conical end of the iron core can gradually move out from the direction away from the valve port; it can be understood that the amount of movement of this end is the opening degree of the proportional valve 41, and is directly proportional to the magnitude of the current flowing through the coil.

[0064] Referring to Figures 1 to 3 , in an embodiment of the present invention, the proportional valve control device includes:

[0065] A main control device 10, configured to output a proportional valve drive signal and a hysteresis compensation signal; and

[0066] A proportional valve drive circuit 20, configured to control the opening degree of the proportional valve 41 according to the proportional valve drive signal and control the proportional valve 41 to generate jitter according to the hysteresis compensation signal.

[0067] In this embodiment, the main control device 10 can be a microprocessor such as an MCU, a DSP, or an FPGA, or it can also be a CPU main control chip. A variety of functional units can be provided in the main control device 10. For example: a proportional valve drive signal generation unit and a hysteresis compensation signal generation unit. Corresponding hardware circuits and software programs or algorithms can be integrated in each functional unit, and can be connected to other functional modules in the proportional valve control device through corresponding ports or pins. For example: a hysteresis pin and a PWM pin; each functional unit can output corresponding control signals to other functional modules by executing corresponding hardware circuits, running software programs or algorithms, and calling stored data. For example: a PWM generation program, a pulse signal generation circuit, a sine wave / square wave / triangle wave / sawtooth wave generation program, to control their operation. The proportional valve drive signal can be a PWM signal or a dedicated communication data stream; and the hysteresis compensation signal can be an analog signal and a pulse signal. For example: one or more couplings of a sine wave, a square wave, a triangle wave, and a sawtooth wave. This embodiment takes the proportional valve drive signal as a PWM signal as an example for explanation.

[0068] The proportional valve drive circuit 20 can be constructed and implemented using a variety of discrete electronic devices such as switching devices, resistive elements, capacitive elements, and operational amplifier devices, or it can also use a dedicated drive chip; among them, the switching device can be one or a combination of a triode, a MOS tube, an IBGT, and a thyristor. The input end of the proportional valve drive circuit 20 can be connected to a DC power supply, its controlled end can be respectively connected to the proportional valve drive signal and the hysteresis compensation signal, and its output end can be connected to both ends of the coil in the proportional valve 41.

[0069] When it is implemented by a hardware circuit, the proportional valve drive circuit 20 can directly couple the input proportional valve drive signal and the hysteresis compensation signal through its own electronic components, and can use the coupled signal and its own circuit structure to control the magnitude of the current output from the connected DC power supply to the coil. It can be understood that the coupled signal does not change the effects of the original signals, and can be understood as the superposition of the effects of the original signals. When the proportional valve drive signal acts alone, it is used to control the on / off states of the switching devices in the proportional valve drive circuit 20 to control the magnitude of the current output to the coil, thereby realizing the control of the opening degree of the proportional valve 41. When the hysteresis compensation signal acts alone, it can also control the on / off states of the switching devices so that the current received by the proportional valve 41 coil can be a tremor current fluctuating within a small range, so that the electromagnetic force received by the iron core in the proportional valve 41 can also fluctuate within a small range, thereby achieving the purpose of making its iron core in a jitter state. Furthermore, when the two signals are coupled, while controlling the opening degree of the proportional valve, the iron core therein can be controlled to be in a jitter state. When it is implemented by a drive chip, it can directly output a drive current of a corresponding magnitude to the coil according to the received proportional valve drive signal and hysteresis compensation signal to achieve the same control effect as above, so it will not be elaborated here.

[0070] The proportional valve control device of the present invention controls the opening degree of the proportional valve 41 and makes it jitter by setting the main control device 10 and the proportional valve drive circuit 20, and the proportional valve drive circuit 20 respectively controls according to the proportional valve drive signal and the hysteresis compensation signal output by the main control device 10. The proportional valve control device of the present invention makes the iron core in a jitter state while adjusting the opening degree of the proportional valve 41. Compared with the iron core in a stable state, the iron core in a jitter state has less contact with the inner wall of the valve body and bears less friction when moving to adjust the opening degree of the proportional valve. Therefore, when the same drive current flows through the coil, the opening degree adjustment of the valve body can be more accurate, thereby solving the hysteresis problem of the proportional valve 41. When the present invention is applied to a constant temperature gas water heater, it can not only make the constant temperature control more accurate, but also greatly reduce the hysteresis value of the secondary pressure in the gas chamber to within 15 Pa, greatly improving the safety of the gas chamber. Compared with the existing solutions to the hysteresis problem, there is no need to adjust for different models of the proportional valve 41, and the hysteresis compensation signal can be directly superimposed on the original proportional valve drive signal. The adopted circuit structure is simple and easy to implement, which is beneficial to reducing the design cost and development difficulty.

[0071] Referring to Figures 1 to 3 , in an embodiment of the present invention, the hysteresis compensation signal is a square wave signal, and the main control device 10 further includes:

[0072] The hysteresis signal conversion circuit 30 is used to convert the hysteresis compensation signal output by the main control device 10 from a square wave signal into a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal.

[0073] Further, the hysteresis signal conversion circuit 30 includes:

[0074] An integration circuit 31 is used to convert the hysteresis compensation signal output by the main control device 10 from a square wave signal into a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal;

[0075] An amplitude adjustment circuit 32 is used to adjust the amplitude of the first preset waveform signal to a preset amplitude; and

[0076] A coupling circuit 33 is used to couple the first preset waveform signal with adjusted amplitude to the proportional valve drive signal.

[0077] In this embodiment, the hysteresis signal conversion circuit 30 can be either a hardware circuit or a dedicated signal converter such as a microprocessor. The square wave signal output by the main controller can be realized by alternating combination of a high level and a low level. And in another alternative embodiment, the duty cycle of the square wave signal output by the main controller is 50%. When it is a signal converter, the input square wave signal can be compared with a voltage threshold. When the voltage value corresponding to the high level is greater than the voltage threshold, a gradually rising voltage signal can be output according to a first preset rate, and when the voltage value corresponding to the low level is greater than the voltage threshold, a gradually decreasing voltage signal can be output according to a second preset rate, so as to realize the conversion from the square wave signal to the first preset waveform signal. It can be understood that those skilled in the art can control various signal parameters of the first preset waveform signal by setting the output time of each high / low level in the square wave signal, as well as the first preset rate and the second preset rate, such as: signal type (sawtooth wave, triangular wave or a combined waveform of the two), signal amplitude and signal frequency, etc.

[0078] When it is implemented by using the integration circuit 31, the amplitude adjustment circuit 32, and the coupling circuit 33, the integration circuit 31 is used to integrate the square wave signal to convert it into a sawtooth wave signal and / or a triangular wave signal; the amplitude adjustment circuit 32 is used to adjust the amplitude of the converted sawtooth wave signal and / or triangular wave signal so that the adjusted signal can control the iron core of the proportional valve 41 to generate corresponding jitters through the proportional valve drive circuit 20, so as to avoid the influence of the jitters generated by too large an amplitude on the opening control; the coupling circuit 33 is used to couple the converted first preset waveform signal to the proportional valve drive signal so that the signal received by the proportional valve drive circuit 20 is the coupled signal. It can be understood that the sawtooth wave signal and / or triangular wave signal with multiple levels has a better jitter effect than the square wave signal with only two levels.

[0079] Of course, in other alternative embodiments, the hysteresis compensation signal can also be other waveform signals, and other methods can be used for waveform conversion. For example, the hysteresis compensation signal can also be a high-level signal, and this high-level signal can be directly output to a variety of waveform generators to trigger them to directly output the corresponding first preset waveform signal. The technical solution of the present invention using the square wave signal as the hysteresis compensation signal can be adapted to all types of proportional valve control devices without adding a signal output module to the original proportional valve control device. By setting the integration circuit 31, the hysteresis compensation signal of the square wave signal can be converted into a sawtooth wave signal and / or a triangular wave signal with a better jitter effect, and the triggered jitter effect can be further optimized through amplitude adjustment so that it can generate jitters in the control of the proportional valve iron core without affecting its opening control.

[0080] Referring to Figures 1 to 3 , in an embodiment of the present invention, the integration circuit 31 includes: an integration resistor Rc and an integration capacitor Cc; the integration resistor Rc has a first end and a second end, and the first end of the integration resistor Rc is the input end of the integration circuit 31 for accessing the square wave signal output by the main control device 10 and outputting it to the first end of the integration capacitor Cc through its second end, and the second end of the integration capacitor Cc is grounded; wherein, the second end of the integration resistor Rc and the second end of the integration capacitor Cc are respectively the first output end and the second output end of the integration circuit 31.

[0081] In this embodiment, the integrating capacitor Cc can be used to store energy and boost the voltage when the first end of the integrating resistor Rc receives a high-level signal in the square wave signal. At this time, the signal waveform output by the first output end and the second output end of the integrating circuit 31 can correspond to the rising edge of the sawtooth wave signal and / or the triangular wave signal; and when the low-level signal in the square wave signal is received, the voltage waveform output by the two output ends of the integrating circuit 31 can correspond to the falling edge of the sawtooth wave signal and / or the triangular wave signal. By adjusting the size relationship between the capacitance value of the integrating capacitor Cc and the resistance value of the integrating resistor Rc, the signal type of the first preset waveform signal can be switched. By setting the integrating resistor Rc and the integrating capacitor Cc, the square wave signal can be converted into the first preset waveform signal with better jitter effect with the simplest circuit structure, which reduces the design cost and is beneficial to the wiring design on the electric control board.

[0082] Reference Figures 1 to 3 In one embodiment of the present invention, the amplitude adjustment circuit 32 includes: a first amplitude adjustment resistor Ra and a second amplitude adjustment resistor Rb; the first end of the first amplitude adjustment resistor Ra is the first input end of the amplitude adjustment circuit 32; the first end of the second amplitude adjustment resistor Rb is the second input end of the amplitude adjustment circuit 32, and the second end of the second amplitude adjustment resistor Rb is connected to the second end of the first amplitude adjustment resistor Ra; the common end of the first amplitude adjustment resistor Ra and the second amplitude adjustment resistor Rb is the output end of the amplitude adjustment circuit 32.

[0083] In this embodiment, the first amplitude adjustment resistor Ra and the second amplitude adjustment resistor Rb form a voltage divider circuit, which is used to adjust the amplitude of the first preset waveform signal by using the principle of voltage division. It should be noted that the first amplitude adjustment resistor Ra and the second amplitude adjustment resistor Rb can use fixed value resistors or adjustable resistance resistors; when both use adjustable resistance resistors, the controlled ends of the two can be connected to the main control device 10 respectively,

[0084] to adjust the amplitude of the first preset waveform signal to any value between 0 and the maximum amplitude under the control of the main control device 10; when both use fixed-value resistors, the optimal resistance ratio between the two can be obtained through multiple pre-experiments (the first preset waveform signal adjusted by the amplitude adjustment circuit 32 with the optimal resistance ratio can minimize the frictional force between the iron core and the valve body wall). In an alternative embodiment, the amplitude of the first preset waveform signal converted by the integration circuit 31 is 5V, and after being adjusted to 100mV by the amplitude adjustment circuit 32, it is output. It can be understood that by adjusting the amplitude of the first preset waveform signal converted by the integration circuit 31, it is possible to prevent the first preset waveform signal with too large an amplitude from causing excessive jitter of the iron core and affecting the opening control effect, and also to prevent the first preset waveform signal with too small an amplitude from causing too small jitter of the iron core, thereby affecting the solution of the hysteresis problem.

[0085] Referring to Figures 1 to 3 , in an embodiment of the present invention, the coupling circuit 33 includes: a coupling capacitor Cs; the first end of the coupling capacitor Cs is the input end of the coupling circuit 33, and the second end of the coupling capacitor Cs is the output end of the coupling circuit 33.

[0086] In this embodiment, since the first preset waveform signal is not in the form of direct current, a capacitor device is selected as the coupling device to couple the first preset waveform signal to the proportional valve drive signal. It can be understood that in practical applications, the coupling circuit 33 can also be selected according to the type of the first preset waveform signal, for example: other coupling devices such as resistance elements are used to construct and implement. In this way, the first preset waveform signal can be coupled to the proportional valve drive signal and then jointly output to the proportional valve drive circuit 20. Compared with being output to the proportional valve drive circuit 20 separately, there is no need to adjust the circuit structure of the original proportional valve drive circuit 20, so that the hysteresis signal conversion circuit 30 can be adapted to the proportional valve drive circuits 20 of all models of proportional valves.

[0087] Referring to Figures 1 to 3 , in an embodiment of the present invention, the main control device 10 is further configured to receive a proportional valve control command and generate a proportional valve drive signal according to the proportional valve control command;

[0088] The main control device 10 is further configured to obtain the frequency of the proportional valve drive signal, perform a multiplication calculation on the frequency and a first preset proportional parameter, and configure the calculation result as the frequency parameter of the hysteresis compensation signal;

[0089] The main control device 10 is further configured to output a hysteresis compensation signal in the form of a square wave signal according to a preset duty cycle parameter and the frequency parameter.

[0090] Further, the first preset proportional parameter is 10%.

[0091] In this embodiment, the proportional valve control device can also be connected to functional modules such as a communication circuit or a key circuit for inputting the proportional valve control instruction output by the above functional modules. When the main control device 10 receives the proportional valve control instruction, it can run a corresponding software program or algorithm to analyze it to determine the control information represented by the trigger. For example: the degree of increasing / decreasing the opening of the control valve body, and can call the corresponding PWM parameters according to the determination result and a variety of pre-stored mapping relationships to generate a corresponding PWM signal. It can be understood that the PWM parameters can include a frequency parameter and a duty cycle parameter. When the main control device 10 calls the corresponding PWM parameters, it can also send the frequency parameter therein to the hysteresis compensation signal generation unit therein, so that the hysteresis compensation signal generation unit can multiply the called frequency parameter by the first preset ratio parameter and then configure the calculation result as the frequency parameter of the hysteresis compensation signal. The hysteresis compensation signal generation unit can also store a preset duty cycle parameter to call the preset duty cycle parameter after configuring the frequency parameter, and then generate a square wave signal with the corresponding frequency and duty cycle according to the two, so as to realize the adjustment of the proportional valve opening. It should be noted that the received proportional valve control instruction is a real-time instruction, that is, the frequency of the proportional valve drive signal is also a real-time frequency, and the finally configured frequency parameter of the hysteresis compensation signal is also a real-time frequency parameter.

[0092] In this embodiment, the first preset ratio parameter is selected as 10%, and this value is the optimal value based on the circuit structure shown in this embodiment. In practical applications, when the values of each resistor and capacitor in the circuit structure shown in this embodiment are different or other circuit structures are adopted for each circuit module, the first preset ratio parameter can be selected from any value between 0 and 100%. And when selecting, the actual application product needs to be considered. For example: when applied to the gas proportional valve of a water heater, this value is not easy to be selected too large to avoid potential safety hazards caused by too large jitter frequency. The present invention converts the real-time frequency of the proportional valve control signal into the frequency of the hysteresis compensation signal according to a certain ratio, so that the jitter of the iron core can always match the opening size thereof, and then the hysteresis problem under different openings can be solved.

[0093] Refer to Figures 1 to 3, in an embodiment of the present invention, the proportional valve drive circuit 20 includes: a first operational amplifier U1, a first switching device T1, a second switching device T2, a first capacitor C1, a second capacitor C2, a third capacitor C3, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a ninth resistor R9; the first end and the second end of the first resistor R1 are respectively the first input end and the second input end of the proportional valve drive circuit 20; the positive input end of the first operational amplifier U1 is connected to the first end of the first resistor R1, its negative input end is connected to the second end of the first resistor R1 through the first capacitor C1, the negative input end is further connected to the first end of the eighth resistor R8 through the seventh resistor R7, and the second end of the eighth resistor R8 is the second output end of the proportional valve drive circuit 20; the output end of the operational amplifier is grounded through the second resistor R2 and the second capacitor C2, and the common end of the second resistor R2 and the second capacitor C2 is further connected to a DC voltage input end; the output end of the operational amplifier is further connected to the controlled end of the first switching device T1 through the fourth resistor R4; the fifth resistor R5 and the sixth resistor R6 are connected in parallel to form a resistor unit; the input end of the first switching device T1 is connected to the input end of the second switching device through the resistor unit, and the output end of the first switching device T1 is connected to the second end of the eighth resistor R8; the input end of the second switching device is connected to its output end, and the common end of the two is the first output end of the proportional valve drive circuit 20; the output end of the first operational amplifier U1 is further connected to the second end of the eighth resistor R8 through the third resistor R3; the output end of the first operational amplifier U1 is further connected to its negative input end through the third capacitor C3.

[0094] In this embodiment, the first output terminal and the second output terminal of the proportional valve drive circuit 20 can be respectively connected to both ends of the coil in the proportional valve 41. The positive input terminal of the first operational amplifier U1 can be used to access the combined signal after coupling the proportional valve drive signal and the hysteresis compensation signal, and is used to amplify the signal through operation and then output it to the first switching device T1 and the second switching device T2, so as to control the magnitude of the drive current output to the coil of the proportional valve 41 by changing the working states of the first switching device T1 and the second switching device T2. Therefore, in this embodiment, the first switching device T1 and the second switching device T2 can be implemented by current-type switching devices such as triodes. The second capacitor C2, the second capacitor C2, and the third capacitor C3 can all be filter capacitors. In another alternative embodiment, a prompting unit such as an LED lamp D1 can also be provided between the output terminal of the proportional valve drive circuit 20 and the coil, so as to issue corresponding prompt information according to the magnitude of the drive current in the coil. And in this embodiment, a fourth capacitor C4 for filtering and a tenth resistor R10 for current limiting are also provided between the proportional valve drive circuit 20 and the main control device 10. The combined signal after coupling can be converted into a drive current of a corresponding magnitude through the hardware circuit, so as to solve the hysteresis problem while controlling the opening of the proportional valve 41.

[0095] The present invention also proposes a proportional valve control method.

[0096] Referring to Figure 4 , in an embodiment of the present invention, the proportional valve control method includes the following steps:

[0097] Step S100: Output a proportional valve drive signal and a hysteresis compensation signal, and the hysteresis compensation signal is a square wave signal;

[0098] In this embodiment, when the proportional valve control device is working, it can directly output a proportional valve drive signal in the form of a PWM signal or a communication data stream and a hysteresis compensation signal in the form of a square wave signal through the hardware circuit and software program or algorithm integrated in each functional unit in itself; or, the proportional valve control device can also output a signal generation instruction containing multiple signal parameters to a dedicated signal generator, so that the signal generator can obtain the multiple signal parameters contained therein after decoding the signal generation instruction, and generate a proportional valve drive signal and a hysteresis compensation signal with waveforms corresponding to the signal parameters according to the decoding result.

[0099] Step S200: Convert the hysteresis compensation signal from a square wave signal into a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal;

[0100] In this embodiment, the proportional valve control device can output the deadband compensation signal to the corresponding signal conversion circuit or conversion device, so as to convert the deadband compensation signal of the square wave signal into one of a sawtooth wave signal and a triangular wave signal or a combination of both by using its circuit function or the stored software program. The above conversion process can also occur inside the main control device 10. For example, the main control device 10 can also be provided with a first preset waveform signal conversion unit for converting the square wave signal output by the deadband compensation signal generation unit into a first preset waveform signal and then outputting it.

[0101] Step S300: Control the opening degree of the proportional valve 41 according to the proportional valve drive signal and control the proportional valve 41 to generate jitter according to the first preset waveform signal.

[0102] In this embodiment, the proportional valve control device can output the proportional valve drive signal and the first preset waveform signal to the proportional valve drive circuit 20, so that the proportional valve drive circuit 20 can convert them into drive currents of corresponding magnitudes and then output them to the coil of the proportional valve 41. Among them, the proportional valve drive signal can be converted into the main component of the drive current by the proportional valve drive circuit 20 for controlling the opening degree of the proportional valve 41; while the deadband compensation signal can be converted into the fluctuating part of the drive current by the proportional valve drive circuit 20. When it is superimposed on the main component, the overall amplitude of the drive current fluctuates within a preset range, so that while controlling the opening degree of the proportional valve, the iron core of the proportional valve 41 can be controlled to be in a jitter state, thereby solving the deadband problem of the proportional valve 41.

[0103] Referring to Figure 5 , in an embodiment of the present invention, the step S200 of converting the deadband compensation signal from a square wave signal into a sawtooth wave signal and / or a triangular wave signal includes:

[0104] Step S210: Convert the deadband compensation signal output by the main control device 10 from a square wave signal into a first preset waveform signal, and the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal;

[0105] Step S220: Adjust the amplitude of the first preset waveform signal to a preset amplitude;

[0106] Step S230: Couple the first preset waveform signal with adjusted amplitude to the proportional valve drive signal.

[0107] In this embodiment, the main control device 10 can output the hysteresis compensation signal as a square wave signal to the hysteresis signal conversion circuit 30, where the square wave signal can be converted into a sawtooth wave signal and / or a triangular wave signal under the action of the integration circuit 31 therein, and after conversion, it can continue to be output to the amplitude adjustment circuit 32 therein for amplitude adjustment, and finally, through the coupling circuit 33 therein, the amplitude-adjusted sawtooth wave signal and / or triangular wave signal can be coupled to the proportional valve drive signal. By converting the hysteresis compensation signal of the square wave signal into a first preset waveform signal, the jitter effect of the iron core can be improved, and through amplitude adjustment, while controlling the iron core of the proportional valve 41 to generate jitter, the opening control thereof will not be affected.

[0108] Referring to Figure 6 , in an embodiment of the present invention, before performing the step S100 of outputting the proportional valve drive signal and the hysteresis compensation signal, the proportional valve control method further includes the following steps:

[0109] Step S400: Receive a proportional valve control instruction, and generate a proportional valve drive signal according to the proportional valve control instruction;

[0110] Step S500: Obtain the frequency of the proportional valve drive signal, perform a multiplication calculation on the frequency and a first preset proportional parameter, and configure the calculation result as the frequency parameter of the hysteresis compensation signal;

[0111] Step S600: Output the hysteresis compensation signal of the square wave signal according to a preset duty ratio parameter and the frequency parameter.

[0112] Further, the first preset proportional parameter is 10%.

[0113] In this embodiment, when the proportional valve control device receives a proportional valve control instruction characterizing the opening control degree of the proportional valve, it can generate a proportional valve drive signal with a corresponding frequency according to the opening control degree characterized thereby, and select 10% of the frequency of the proportional valve drive signal as the frequency parameter of the hysteresis compensation signal, so that the proportional valve control device can continue to generate the hysteresis compensation signal of the square wave signal according to the frequency parameter of the hysteresis compensation signal and the preset duty ratio parameter. It should be noted that the selection logic of the first preset proportional parameter can refer to the foregoing description and will not be elaborated herein. With such a setting, the hysteresis compensation signal can be automatically adjusted in real time according to the frequency of the proportional valve drive signal, so that the jitter of the iron core can be matched with its opening size at any time, thereby solving the hysteresis problem under different openings.

[0114] The present invention also proposes a gas water heater.

[0115] Referring to Figures 1 to 3 and Figure 7 , in an embodiment of the present invention, the gas water heater includes:

[0116] The water heater main body 40;

[0117] A proportional valve 41, the proportional valve 41 is arranged in the water heater main body 40; and

[0118] It further includes the above-mentioned proportional valve control device, the proportional valve control device is arranged in the water heater main body 40 and is connected to the proportional valve 41; or, the above-mentioned proportional valve control method is used.

[0119] In this embodiment, functional components such as a gas chamber, a heat exchanger, and a safety device may be provided in the water heater main body 40. The valve port of the proportional valve 41 can be connected to the gas chamber to adjust the air-gas ratio output to the gas chamber, thereby realizing the control of the combustion temperature in the gas chamber. The output end of the proportional valve control device can be connected to both ends of the coil in the proportional valve 41 to realize the above-mentioned proportional valve control method when outputting a drive current to control the operation of the proportional valve 41.

[0120] Referring to Figures 1 to 3 and Figure 7 , in an embodiment of the present invention, the gas water heater further includes:

[0121] An inlet water pipeline 50;

[0122] A hot water pipeline 60, the inlet water pipeline 50 and the hot water pipeline 60 are respectively connected to the water heater main body 40;

[0123] A first temperature sensor 70, the first temperature sensor 70 is arranged in the inlet water pipeline 50 for detecting the inlet water temperature of the inlet water pipeline 50 and outputting a first temperature detection signal;

[0124] A second temperature sensor 80, the second temperature sensor 80 is arranged in the hot water pipeline 60 for detecting the outlet water temperature of the hot water pipeline 60 and outputting a second temperature detection signal;

[0125] A temperature adjustment module 90, the temperature adjustment module 90 is arranged on the water heater main body 40, and the temperature adjustment module 90 is used for accessing a temperature adjustment signal and outputting it to the proportional valve control device;

[0126] The proportional valve control device is further used for generating a proportional valve drive signal according to the first temperature detection signal, the second temperature detection signal, and the temperature adjustment signal to perform constant temperature control on the water discharged from the hot water pipeline 60.

[0127] In this embodiment, the inlet water pipeline 50 is used for accessing the water of the water supply system, and the hot water pipeline 60 is used for discharging the water heated by the gas chamber.

[0128] Both the first temperature sensor 70 and the second temperature sensor 80 can be implemented by temperature-sensitive devices, and the output ends of both can be connected to the proportional valve control device. The first temperature sensor 70 is used to output an electrical signal corresponding to the inlet water temperature, i.e., the first temperature detection signal, by utilizing its own thermal sensitivity when the water inlet pipe 50 is in water inlet; since the working principle of the second temperature sensor 80 is the same as that of the first temperature sensor 70, it will not be elaborated here.

[0129] The temperature adjustment module 90 can be one or a combination of a key unit, a wireless communication unit, or a wired communication unit. The temperature adjustment module 90 can be used to access the temperature adjustment signal representing the target temperature and output it to the main control device 10 in the proportional valve control device. It can be understood that the temperature adjustment signal can be one of the proportional valve control instructions in the foregoing embodiments.

[0130] The main control device 10 in the proportional valve control device can respectively receive the first temperature detection signal, the second temperature detection signal, and the temperature adjustment signal, and can determine the adjustment degree of the proportional valve opening according to the above three signals in different control stages of the gas water heater, and can also generate a corresponding proportional valve drive signal according to the determination result, so that the adjusted proportional valve opening can maintain the temperature of the water discharged from the hot water pipe 60 constant. For example, in the stage when the gas water heater is just started, the main control device 10 in the proportional valve control device can determine the temperature difference between the inlet water temperature and the target temperature according to the first temperature detection signal and the temperature adjustment signal, and output a proportional valve drive signal according to this temperature difference to control the valve body opening so that the water outlet temperature of the hot water pipe 60 quickly reaches the target temperature; in the subsequent control stage, the main control device 10 can also determine the temperature difference between the water outlet temperature and the target temperature according to the second temperature detection signal and the temperature adjustment signal, and can make corresponding parameter adjustments to the output proportional valve drive signal according to this temperature difference, so that the adjusted proportional valve drive signal can control the opening of the proportional valve 41 to increase / decrease correspondingly, and further make the water outlet temperature of the outlet pipe rise / fall correspondingly, repeating the above process to achieve the purpose of constant temperature control of the water outlet temperature of the hot water pipe 60. By adopting the above proportional valve control device and the above proportional valve control method, the gas water heater of the present invention solves the problem of the dead zone of the proportional valve 41, so it is beneficial to improve the accuracy of constant temperature control, and since the dead zone value of the secondary pressure is reduced, the safety of the gas water heater can be further improved.

[0131] It can be understood that Figure 7 the functional modules of the gas water heater shown in

[0132] The above are only alternative embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made by using the content of the specification and drawings of the present invention under the inventive concept of the present invention, or any direct / indirect application in other related technical fields shall be included within the patent protection scope of the present invention.

Claims

1. A proportional valve control device, characterized in that, The proportional valve control device includes: A main control device for outputting a proportional valve drive signal and a hysteresis compensation signal; and A proportional valve drive circuit for controlling the opening degree of the proportional valve according to the proportional valve drive signal and controlling the proportional valve to generate jitter according to the hysteresis compensation signal; The proportional valve drive circuit includes: a first operational amplifier, a first switching device, a second switching device, a first capacitor, a second capacitor, a third capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor; the first end and the second end of the first resistor are respectively the first input end and the second input end of the proportional valve drive circuit; the positive input end of the first operational amplifier is connected to the first end of the first resistor, its negative input end is connected to the second end of the first resistor through the first capacitor, the negative input end is also connected to the first end of the eighth resistor through the seventh resistor, and the second end of the eighth resistor is the second output end of the proportional valve drive circuit; the output end of the operational amplifier is grounded through the second resistor and the second capacitor, and the common end of the second resistor and the second capacitor is also connected to a DC voltage input end; the output end of the operational amplifier is also connected to the controlled end of the first switching device through the fourth resistor; the fifth resistor and the sixth resistor are connected in parallel to form a resistor unit; the input end of the first switching device is connected to the input end of the second switching device through the resistor unit, and the output end of the first switching device is connected to the second end of the eighth resistor; the input end of the second switching device is connected to its output end, and the common end of the two is the first output end of the proportional valve drive circuit; the output end of the first operational amplifier is also connected to the second end of the eighth resistor through the third resistor; the output end of the first operational amplifier is also connected to its negative input end through the third capacitor.

2. The proportional valve control device according to claim 1, wherein The hysteresis compensation signal is a square wave signal, and the main control device further includes: A hysteresis signal conversion circuit for converting the hysteresis compensation signal output by the main control device from a square wave signal into a first preset waveform signal, where the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal.

3. The proportional valve control device according to claim 2, wherein The hysteresis signal conversion circuit includes: An integration circuit for converting the hysteresis compensation signal output by the main control device from a square wave signal into a first preset waveform signal, where the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal; An amplitude adjustment circuit for adjusting the amplitude of the first preset waveform signal to a preset amplitude; and A coupling circuit for coupling the amplitude-adjusted first preset waveform signal to the proportional valve drive signal.

4. The proportional valve control device according to claim 3, wherein, The integrating circuit includes: an integrating resistor and an integrating capacitor; the integrating resistor has a first end and a second end, the first end of the integrating resistor is the input end of the integrating circuit for accessing the square wave signal output by the main control device and outputting it from the second end to the first end of the integrating capacitor, and the second end of the integrating capacitor is grounded; wherein, the second end of the integrating resistor and the second end of the integrating capacitor are respectively the first output end and the second output end of the integrating circuit.

5. The proportional valve control device according to claim 3, characterized in that, The amplitude adjustment circuit includes: a first amplitude adjustment resistor and a second amplitude adjustment resistor; the first end of the first amplitude adjustment resistor is the first input end of the amplitude adjustment circuit; the first end of the second amplitude adjustment resistor is the second input end of the amplitude adjustment circuit, and the second end of the second amplitude adjustment resistor is connected to the second end of the first amplitude adjustment resistor; the common end of the first amplitude adjustment resistor and the second amplitude adjustment resistor is the output end of the amplitude adjustment circuit.

6. The proportional valve control device according to claim 3, characterized in that, The coupling circuit includes: a coupling capacitor; the first end of the coupling capacitor is the input end of the coupling circuit, and the second end of the coupling capacitor is the output end of the coupling circuit.

7. The proportional valve control device according to claim 2, characterized in that, The main control device is further configured to receive a proportional valve control instruction and generate a proportional valve drive signal according to the proportional valve control instruction; The main control device is further configured to obtain the frequency of the proportional valve drive signal, perform a multiplication calculation on the frequency and a first preset proportional parameter, and configure the calculation result as the frequency parameter of the deadband compensation signal; The main control device is further configured to output a deadband compensation signal of the square wave signal according to a preset duty ratio parameter and the frequency parameter.

8. The proportional valve control device according to claim 7, wherein, The first preset proportional parameter is 10%.

9. A proportional valve control method, characterized in that, The proportional valve control method is applied to the proportional valve control device as claimed in claim 1, and the proportional valve control method includes the following steps: Output a proportional valve drive signal and a deadband compensation signal, where the deadband compensation signal is a square wave signal; Convert the deadband compensation signal from a square wave signal to a first preset waveform signal, where the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal; and Control the opening degree of the proportional valve according to the proportional valve drive signal and control the proportional valve to generate jitter according to the first preset waveform signal.

10. The proportional valve control method according to claim 9, characterized in that, The step of converting the deadband compensation signal from a square wave signal to a sawtooth wave signal and / or a triangular wave signal includes: Convert the deadband compensation signal output by the main control device from a square wave signal to a first preset waveform signal, where the first preset waveform signal includes a sawtooth wave signal and / or a triangular wave signal; Adjust the amplitude of the first preset waveform signal to a preset amplitude; and Couple the first preset waveform signal with the adjusted amplitude to the proportional valve drive signal.

11. The proportional valve control method according to claim 9, characterized in that, Before performing the step of outputting the proportional valve drive signal and the deadband compensation signal, the proportional valve control method further includes the following steps: Receive a proportional valve control instruction and generate a proportional valve drive signal according to the proportional valve control instruction; Obtain the frequency of the proportional valve drive signal, perform a multiplication calculation on the frequency and a first preset proportional parameter, and configure the calculation result as the frequency parameter of the deadband compensation signal; and Output a hysteresis compensation signal of a square wave signal according to a preset duty cycle parameter and the frequency parameter.

12. The proportional valve control method according to claim 11, wherein The first preset ratio parameter is 10%.

13. A gas water heater, characterized in that, The gas water heater includes: A water heater main body; A proportional valve, which is arranged in the water heater main body; and It further includes a proportional valve control device according to any one of claims 1-8, the proportional valve control device is arranged in the water heater main body and is connected to the proportional valve.

14. A gas water heater, characterized in that, The gas water heater includes: A water heater main body; A proportional valve, which is arranged in the water heater main body; The gas water heater uses a proportional valve control method according to any one of claims 9-12.

15. The gas water heater according to claim 13 or 14, characterized in that, The gas water heater further includes: A water inlet pipeline; A hot water pipeline, the water inlet pipeline and the hot water pipeline are respectively connected to the water heater main body; A first temperature sensor, which is arranged in the water inlet pipeline and is used to detect the water inlet temperature of the water inlet pipeline and output a first temperature detection signal; A second temperature sensor, which is arranged in the hot water pipeline and is used to detect the water outlet temperature of the hot water pipeline and output a second temperature detection signal; and A temperature adjustment module, which is arranged on the water heater main body, and the temperature adjustment module is used to receive a temperature adjustment signal and output it to the proportional valve control device; The proportional valve control device is further used to generate a proportional valve drive signal according to the first temperature detection signal, the second temperature detection signal and the temperature adjustment signal to perform constant temperature control on the water discharged from the hot water pipeline.

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