Multi-path electromagnetic valve time division multiplexing power supply system

Abstract

The invention discloses a time-sharing multiplexing power supply system for multiple electromagnetic valves, relates to the technical field of electromagnetic valve power supply, and can distinguish and identify power-on instructions issued by an external upper computer and perform time-sharing power supply for different electromagnetic valves. A control circuit of a plurality of groups of switch MOS tubes is introduced, which switch MOS tube is controlled to be switched on when which switch MOS tube needs to be switched on for power supply, and other switch MOS tubes are switched off. Therefore, in the same control system, the electromagnetic valves which do not need to be powered simultaneously can share one electromagnetic valve power supply system for switching power supply, under the condition that application requirements are met, the use number of the electromagnetic valve power supply system is reduced, and the purpose of reducing cost is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of solenoid valve power supply, and particularly to a time-division multiplexing power supply system for a multi-way solenoid valve. Background Art

[0002] A solenoid valve is an automated component that controls fluid using electromagnetism. For a normally closed solenoid valve, when the electromagnetic coil of the solenoid valve is energized, the electromagnetic coil generates an electromagnetic attraction force. The electromagnetic attraction force overcomes the elastic force of the spring and lifts the valve core, opening the valve. When the solenoid valve coil is de-energized, the electromagnetic coil no longer generates an electromagnetic attraction force, and the closing element presses against the valve seat under the action of the spring force, closing the valve. The resistive component of the solenoid valve determines the magnitude of the required solenoid valve activation current value and the solenoid valve holding current value, and the inductive component of the solenoid valve affects the speed of the conversion time. For example, the larger the inductive component of the solenoid valve, the larger the solenoid valve activation current establishment time, the conversion time of the solenoid valve from the activation state to the holding state, and the solenoid valve closing time will become. The solenoid valve drive current waveform is as Figure 3 shown.

[0003] Figure 3 In the figure, Imax is the solenoid valve activation current value, Imin is the solenoid valve holding current value, t1 to t2 is the solenoid valve activation current establishment time, t2 to t3 is the solenoid valve activation time, t3 to t4 is the conversion time of the solenoid valve from the activation state to the holding state, t4 to t n0 is the solenoid valve holding time, and t n1 to t n2 is the solenoid valve closing time.

[0004] According to different actual application requirements, it is generally recommended that the drive current of high-power solenoid valves strictly provide drive current for the solenoid valves in high and low stages as shown in the above drive current waveform diagram. For the drive current of low-power solenoid valves, a single drive current can be used without dividing into stages (because high-power solenoid valves have a large power base, if the activation current level is always maintained for power supply, then a large amount of energy will be wasted during the stage when the solenoid valve maintains operation. Therefore, energy must be saved as much as possible. For low-power solenoid valves, because their power is small, even if they operate in stages, not much energy will be saved).

[0005] The existing technical solution still focuses on the power supply driving technology for a single solenoid valve. That is, a fixed-output driving power supply powers the entire driving circuit. The controller receives the energization instruction sent from an external host computer. The switching MOS transistor is controlled by the controller to switch between the on and off states. The constant current control circuit receives the signal conditioned by the controller and keeps the driving current constant at a set value. The excess voltage is restricted between the drain and source of the constant current MOS transistor in the constant current control circuit. The feedback monitoring circuit converts the analog signal into a digital signal after collecting the pressure difference across the sampling resistor and transmits it to the controller, realizing the closed-loop control of the driving current by the controller. The principle block diagram is as shown in Figure 4 shown.

[0006] It can be seen that the main disadvantage of the existing technical solution is that a solenoid valve power supply system can only supply power to one path of solenoid valves, resulting in too high costs. Summary of the Invention

[0007] In view of the above problems, the present invention provides a multiplexed solenoid valve time-division multiplexing power supply system for overcoming the above problems or at least partially solving the above problems. Under specific timing control conditions, the solenoid valve power supply system in this system realizes one-to-many power supply to solenoid valves, further saving hardware costs and reducing the production costs of enterprises.

[0008] The present invention provides the following solutions:

[0009] A multiplexed solenoid valve time-division multiplexing power supply system, comprising:

[0010] A main controller, a fixed-output driving power supply, a constant current control circuit, a constant current MOS transistor, and at least two sets of switching units;

[0011] The constant current control circuit is respectively connected to the main controller and the constant current MOS transistor;

[0012] Each set of the switching units includes two switching MOS transistors. Different solenoid valves are connected between the two switching MOS transistors included in different switching units. One of the switching MOS transistors in each set of the switching units is connected to the fixed-output driving power supply, and the other switching MOS transistor in each set of the switching units is connected to the constant current MOS transistor; the solenoid valves included in different switching units do not need to be powered simultaneously;

[0013] All the switching MOS transistors are connected to the main controller, and the main controller is used to perform the following operations:

[0014] Receive the first energization instruction sent by an external host computer, and determine the switch unit where the first solenoid valve to be energized included in the first energization instruction is located as the first target switch unit, where the first target switch unit is any one of at least two sets of the switch units;

[0015] Control each of the switching MOS transistors included in the first target switch unit to conduct and control all the switching MOS transistors included in other switch units among at least two sets of the switch units to turn off, so as to supply the required power supply to the first solenoid valve to be energized through the first target switch unit;

[0016] Receive the second energization instruction sent by an external host computer, and determine the switch unit where the second solenoid valve to be energized included in the second energization instruction is located as the second target switch unit, where the second target switch unit is any one of at least two sets of the switch units excluding the first target switch unit;

[0017] Control each of the switching MOS transistors included in the second target switch unit to conduct and control all the switching MOS transistors included in other switch units among at least two sets of the switch units to turn off, so as to supply the required power supply to the second solenoid valve to be energized through the second target switch unit.

[0018] Preferably: The constant current control circuit includes a first digital-to-analog converter and a first operational amplifier circuit. The first digital-to-analog converter is used to output a reference voltage according to an instruction issued by the main controller, and the first operational amplifier circuit is used to condition the reference voltage to obtain the gate-source voltage required by the constant current MOS transistor.

[0019] Preferably: The constant current MOS transistor includes a power N-channel MOSFET.

[0020] Preferably: It further includes a feedback monitoring circuit, and the feedback monitoring circuit is connected to the constant current MOS transistor and the main controller.

[0021] Preferably: The feedback monitoring circuit includes a sampling resistor, a second operational amplifier circuit, and a second analog-to-digital converter; the current of the power supply link is reflected by the voltage difference across the sampling resistor, which is conditioned by the second operational amplifier circuit to a voltage magnitude that meets the input conditions of the analog-to-digital converter, and the collected analog signal is converted into a digital signal by the second analog-to-digital converter and sent back to the main controller.

[0022] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0023] A time-division multiplexing power supply system for a multi-way solenoid valve provided by an embodiment of the present application can distinguish and identify power-on instructions issued by an external host computer, and perform time-division power supply for different solenoid valves. By introducing a control circuit of multiple groups of switching MOS transistors, when a certain path needs to be turned on for power supply, the switching MOS transistor of that path is controlled to turn on, while the other switching MOS transistors are turned off. Therefore, in the same control system, solenoid valves that do not need to be powered simultaneously can share a set of solenoid valve power supply systems for switching power supply. Under the condition of meeting the application requirements, the number of solenoid valve power supply systems used is reduced, achieving the purpose of cost reduction.

[0024] Of course, it is not necessary for any product implementing the present invention to achieve all the above advantages simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] 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 to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0026] Figure 1 is a schematic diagram of the principle of a time-division multiplexing power supply system for a multi-way solenoid valve provided by an embodiment of the present invention;

[0027] Figure 2 is a schematic diagram of the power supply timing control of a three-way solenoid valve provided by an embodiment of the present invention;

[0028] Figure 3 is a waveform diagram of the solenoid valve drive current;

[0029] Figure 4 is a principle block diagram of a solenoid valve drive circuit in the prior art.

[0030] In the figure: main controller 1, fixed output drive power supply 2, constant current control circuit 3, constant current MOS transistor 4, No. 1 switching MOS transistor 5, No. 2 switching MOS transistor 6, No. 3 switching MOS transistor 7, No. 4 switching MOS transistor 8, feedback monitoring circuit 9. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention.

[0032] See Figure 1, a multiplex solenoid valve time-division multiplexing power supply system provided by an embodiment of the present invention, as Figure 1 shown, the system may include:

[0033] A main controller 1, a fixed output drive power supply 2, a constant current control circuit 3, a constant current MOS transistor 4, and at least two sets of switching units;

[0034] The constant current control circuit 3 is respectively connected to the main controller 1 and the constant current MOS transistor 4;

[0035] Each set of the switching units includes two switching MOS transistors. Different solenoid valves are connected between the two switching MOS transistors included in different switching units. One of the switching MOS transistors in each set of the switching units is connected to the fixed output drive power supply 2, and the other switching MOS transistor in each set of the switching units is connected to the constant current MOS transistor 4; The solenoid valves included in different switching units do not need to be powered simultaneously;

[0036] All the switching MOS transistors are connected to the main controller 1, and the main controller 1 is used to perform the following operations:

[0037] Receive a first power-on instruction sent by an external host computer, and determine the switching unit where the first solenoid valve to be powered on included in the first power-on instruction is located as the first target switching unit, and the first target switching unit is any one of at least two sets of the switching units;

[0038] Control each of the switching MOS transistors included in the first target switching unit to conduct and control all the switching MOS transistors included in the other switching units in at least two sets of the switching units to turn off, so as to provide the required power supply to the first solenoid valve to be powered on through the first target switching unit;

[0039] Receive a second power-on instruction sent by an external host computer, and determine the switching unit where the second solenoid valve to be powered on included in the second power-on instruction is located as the second target switching unit, and the second target switching unit is any one of at least two sets of the switching units excluding the first target switching unit;

[0040] Control each of the switching MOS transistors included in the second target switching unit to conduct and control all the switching MOS transistors included in the other switching units in at least two sets of the switching units to turn off, so as to provide the required power supply to the second solenoid valve to be powered on through the second target switching unit.

[0041] The system provided by this application is mainly aimed at the application scenario in complex industrial control systems where there is a need for sequential control of an actuator mechanism composed of multiple solenoid valves. Generally, a single solenoid valve requires a dedicated solenoid valve power supply system for power supply and drive. If there are a large number of solenoid valves, correspondingly, an equal number of solenoid valve power supply systems are also required to supply power to the above-mentioned multiple solenoid valves. In actual applications, when there is a situation where solenoid valves do not work simultaneously in pairs, the multiplexed time-sharing power supply technology for multiple solenoid valves provided by the embodiments of this application can be applied, enabling a single solenoid valve power supply system to provide drive power to multiple solenoid valves at different time periods respectively, reducing the required number of supporting solenoid valve power supply systems and lowering the costs of enterprises.

[0042] The fixed output drive power supply 2 provided by the embodiments of this application is a high-voltage DC power supply, providing the necessary DC power supply for the solenoid valve. The main controller 1 receives the energization command signal sent from an external host computer, and through configuring the IO port and increasing the drive ability through a triode, controls the switching of the No. 1 - 4 switch MOS transistors, realizing the conduction and cut-off of the required power supply path.

[0043] Specifically in implementation, the embodiments of this application can provide that the constant current control circuit 3 includes a first digital-to-analog converter and a first operational amplifier circuit. The first digital-to-analog converter is used to output a reference voltage according to the instruction issued by the main controller 1, and the first operational amplifier circuit is used to condition the reference voltage to obtain the gate-source voltage required by the constant current MOS transistor 4. The constant current control circuit 3 is mainly composed of a first digital-to-analog converter, a first operational amplifier circuit, etc. The main controller 1 issues an instruction to the first digital-to-analog converter to output a reference voltage, and through the first operational amplifier circuit, this reference voltage is conditioned to obtain the gate-source voltage required by the constant current MOS transistor 4.

[0044] The constant current MOS transistor 4 includes a power-type N-channel field-effect MOS transistor. The constant current MOS transistor 4 is a power-type N-channel field-effect MOS transistor, enabling the MOS transistor to operate in the saturation region of the output characteristic curve. In this state, the drain current of the MOS transistor is only related to the magnitude of the gate-source voltage and is basically not affected by the change in the drain-source voltage, achieving the purpose of constant current control.

[0045] Furthermore, it also includes a feedback monitoring circuit 9, which is connected to the constant current MOS transistor 4 and the main controller 1. The feedback monitoring circuit 9 includes a sampling resistor, a second operational amplifier circuit, and a second analog-to-digital converter; the current in the power supply link is reflected by the voltage difference across the sampling resistor. After being conditioned by the second operational amplifier circuit to a voltage magnitude that meets the input conditions of the analog-to-digital converter, the analog quantity signal collected is converted into a digital quantity signal by the second analog-to-digital converter and fed back to the main controller 1.

[0046] The mining monitoring circuit 9 is mainly composed of a sampling resistor, an operational amplifier, an analog-to-digital converter, etc. The current in the power supply link is reflected by the voltage difference across the sampling resistor. Then, it is conditioned by the operational amplifier to a voltage value that meets the input conditions of the analog-to-digital converter. Finally, the analog signal collected is converted into a digital signal by the analog-to-digital converter and sent back to the main controller 1, thereby realizing the closed-loop control of the entire power supply system.

[0047] The following details the system provided by the embodiments of the present application in combination with the power supply timing control requirements of the solenoid valves of three channels A, B, and C.

[0048] As Figure 2 shown in the power supply timing control requirements of the solenoid valves of three channels A, B, and C. It can be seen from Figure 2 this that the action time of solenoid valve A covers the start time of solenoid valve B. The end time of solenoid valve B is basically synchronized with the start time of solenoid valve C. The end time of solenoid valve A is ahead of the start time of solenoid valve C.

[0049] Theoretical analysis: Solenoid valve A and solenoid valve B need to be powered simultaneously within a certain period of time. There is a power supply ambiguity between solenoid valve B and solenoid valve C (there may be a short period of time when both are in the simultaneous power supply state). There is no situation where solenoid valve A and solenoid valve C are powered simultaneously.

[0050] Conclusion: Solenoid valve A and solenoid valve B cannot share a set of solenoid valve power supply systems. Solenoid valve B and solenoid valve C cannot share a set of solenoid valve power supply systems. Solenoid valve A and solenoid valve C can share a set of solenoid valve power supply systems.

[0051] The system provided by the present application makes appropriate adjustments on the basis of the solenoid valve drive circuit in the prior art. By optimizing the power-on instructions sent by the upper computer and adding a control circuit of multiple groups of switching MOS transistors to switch the original power supply line, finally, a set of solenoid valve power supply system can meet the requirements of time-sharing power supply for multiple solenoid valves.

[0052] Taking the time-sharing multiplexed power supply application of solenoid valve A and solenoid valve C as an example, the system provided by the present application makes appropriate adjustments on the basis of the solenoid valve drive circuit in the prior art. The time-sharing multiplexed power supply technology for other multiple solenoid valves can be deduced by analogy. The original power-on instruction controlled by a single IO sent by the upper computer to the main controller 1 is adjusted to a power-on instruction controlled by two IOs. The function of the original one switching MOS transistor is split into switching MOS transistor 5 of No. 1, switching MOS transistor 6 of No. 2, switching MOS transistor 7 of No. 3, and switching MOS transistor 8 of No. 4. Other functional circuits remain unchanged. The principle block diagram is as Figure 1 shown.

[0053] The switching MOS transistor 5 of Switch 1 and the switching MOS transistor 7 of Switch 3 form the switching unit of solenoid valve A, and the switching MOS transistor 6 of Switch 2 and the switching MOS transistor 8 of Switch 4 form the switching unit of solenoid valve C. If the number of solenoid valves that can be time-division multiplexed increases in practical applications, one more switching MOS transistor can be added before and after each solenoid valve.

[0054] When the external host computer issues a power-on command to supply power to solenoid valve A, the main controller 1 determines that the switching unit composed of the switching MOS transistor 5 of Switch 1 and the switching MOS transistor 7 of Switch 3 is the first target switching unit. The main controller 1 controls the conduction of the switching MOS transistor 5 of Switch 1 and the switching MOS transistor 7 of Switch 3 by configuring the IO port and increasing the driving ability through a triode, and controls the switching MOS transistor 6 of Switch 2 and the switching MOS transistor 8 of Switch 4 to turn off by configuring the IO port and increasing the driving ability through a triode. The driving current flows from the positive pole of the fixed output driving power supply 2 through the switching MOS transistor 5 of Switch 1, solenoid valve A, the switching MOS transistor 7 of Switch 3, the constant current MOS transistor 4, and the feedback monitoring circuit 9 and then returns to the negative pole of the fixed output driving power supply 2. The constant current MOS transistor 4 plays a role in stabilizing the current value, and the feedback monitoring circuit 9 plays a role in dynamic monitoring.

[0055] When the external host computer issues a power-on command to supply power to solenoid valve C, the main controller 1 determines that the switching unit composed of the switching MOS transistor 6 of Switch 2 and the switching MOS transistor 8 of Switch 4 is the second target switching unit. The main controller 1 controls the conduction of the switching MOS transistor 6 of Switch 2 and the switching MOS transistor 8 of Switch 4 by configuring the IO port and increasing the driving ability through a triode, and controls the switching MOS transistor 5 of Switch 1 and the switching MOS transistor 7 of Switch 3 to turn off by configuring the IO port and increasing the driving ability through a triode. The driving current flows from the positive pole of the fixed output driving power supply 2 through the switching MOS transistor 6 of Switch 2, solenoid valve C, the switching MOS transistor 8 of Switch 4, the constant current MOS transistor 4, and the feedback monitoring circuit 9 and then returns to the negative pole of the fixed output driving power supply 2. The constant current MOS transistor 4 plays a role in stabilizing the current value, and the feedback monitoring circuit 9 plays a role in dynamic monitoring.

[0056] In summary, the time-division multiplexing power supply system for multiple solenoid valves provided by this application can distinguish and identify the power-on commands issued by the external host computer, and supply power to different solenoid valves in a time-division manner. A control circuit with multiple groups of switching MOS transistors is introduced. When a certain path needs to be conducted for power supply, the switching MOS transistors of that path are controlled to conduct, while the other switching MOS transistors are turned off. Therefore, in the same control system, solenoid valves that do not need to be powered simultaneously can share a set of solenoid valve power supply systems for switching power supply. Under the condition of meeting the application requirements, the number of solenoid valve power supply systems used is reduced, achieving the purpose of cost reduction.

[0057] It should be noted that in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the said element.

[0058] From the description of the above embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0059] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for a system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The systems and system embodiments described above are only illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0060] The above is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A multi-way solenoid valve time-sharing multiplexing power supply system, characterized in that: It includes a main controller, a fixed output driving power supply, a constant current control circuit, a constant current MOS tube and at least two sets of switch units; The constant current control circuit is connected to the main controller and the constant current MOS tube respectively; Each set of the switch units includes two switch MOS tubes, and different solenoid valves are connected between the two switch MOS tubes included in different switch units. One switch MOS tube in each set of the switch units is connected to the fixed output drive power supply, and the other switch MOS tube in each set of the switch units is connected to the constant current MOS tube; the solenoid valves included in different switch units do not need to be powered at the same time; All the switch MOS tubes are connected to the main controller, and the main controller is used to perform the following operations: Receive a first power-on instruction sent by an external host computer, determine a switch unit where a first electromagnetic valve to be powered on contained in the first power-on instruction is located as a first target switch unit, and the first target switch unit is any one of at least two sets of switch units; Controlling each of the switch MOS tubes included in the first target switch unit to be turned on and controlling all the switch MOS tubes included in other switch units in at least two sets of the switch units to be turned off, so as to provide the required power supply to the first solenoid valve to be powered on through the first target switch unit; receiving a second power-on instruction sent by an external host computer, determining a switch unit where a second electromagnetic valve to be powered on is located and included in the second power-on instruction as a second target switch unit, wherein the second target switch unit is any one of at least two sets of the switch units excluding the first target switch unit; The MOS switch tubes contained in the second target switch unit are controlled to be turned on and all the MOS switch tubes contained in other switch units in at least two sets of switch units are controlled to be turned off, so as to provide the required power supply to the second solenoid valve to be powered on through the second target switch unit.

2. The multi-way solenoid valve time-sharing multiplexing power supply system according to claim 1 is characterized in that: The constant current control circuit includes a first digital-to-analog converter and a first operational amplifier circuit. The first digital-to-analog converter is used to output a reference voltage according to an instruction issued by the main controller, and the first operational amplifier circuit is used to condition the reference voltage to obtain the gate-source voltage required by the constant current MOS tube.

3. The multi-way solenoid valve time-sharing multiplexing power supply system according to claim 1 is characterized in that: The constant current MOS tube comprises a power type N-channel field effect MOS tube.

4. The multi-way solenoid valve time-sharing multiplexing power supply system according to claim 1 is characterized in that: It also includes a recovery monitoring circuit, which is connected to the constant current MOS tube and the main controller.

5. The multi-way solenoid valve time-sharing multiplexing power supply system according to claim 4 is characterized in that: The sampling monitoring circuit includes a sampling resistor, a second operational amplifier circuit and a second analog-to-digital converter; the current of the power supply link is reflected in the voltage difference between the two ends of the sampling resistor, which is adjusted to a voltage that meets the input conditions of the analog-to-digital converter through the second operational amplifier circuit, and the collected analog signal is converted into a digital signal through the second analog-to-digital converter and returned to the main controller.

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