An array-type high-pressure generation control system suitable for EHD nozzles

Abstract

This application discloses an array-type high-voltage generation and control system suitable for EHD printheads. The system includes a main control module and multiple high-voltage waveform generation modules. The main control module independently controls each high-voltage waveform generation module, which in turn provides the required high-voltage signals for multiple nozzles. The main control module is configured to output array control signals based on the printing process and print control timing requirements, controlling the corresponding high-voltage waveform generation modules to output multi-stage high-voltage pulse waves, thereby achieving independent on-off control of each nozzle. The control signals include n-channel PWM pulse control signals, each of which includes a DC high-voltage control signal and a pulse wave control signal. The n-channel pulse wave control signals are used to control the order, duty cycle, and frequency of the multi-stage high-voltage pulse waves, and the n-channel DC high-voltage control signals are used to control the magnitude of each stage of the multi-stage high-voltage pulse waves. This application enables independent on-off control of each nozzle in a multi-nozzle EHD printhead.

Description

Technical Field

[0001] The present application belongs to the field of industrial printing, and more specifically, relates to an array-type high-voltage generation control system suitable for EHD type nozzles. Background Art

[0002] In industrial printing equipment, electro-hydrodynamic (EHD) nozzles require a corresponding high-voltage signal. Under the influence of gravity, surface tension, and electric field forces, the solution forms an initial hanging droplet. As the voltage increases, the hanging droplet gradually forms a meniscus at the nozzle. When the voltage reaches a critical value, the force balance is broken, and a droplet is ejected at the tip of the Taylor cone, forming a jet. The nozzles required for industrial printing include single-nozzle EHD and multi-nozzle EHD types. For multi-nozzle EHD printing, a single power supply is currently mostly provided to the nozzle. This method is simple to control, but it cannot achieve independent control of each nozzle parameter. Summary of the Invention

[0003] In response to the defects of the existing technology, the purpose of this application is to provide an array-type high-voltage generation and control system suitable for EHD type nozzles, aiming to solve the problem that the traditional multi-nozzle EHD printing method uses a single power supply and cannot achieve independent control of each nozzle parameter.

[0004] To achieve the above objectives, the present application provides an array-type high-voltage generation control system suitable for an EHD-type nozzle, wherein the EHD-type nozzle includes a plurality of nozzles arranged in an array. The array-type high-voltage generation control system includes a main control module and a multi-channel high-voltage waveform generation module. The main control module independently controls each high-voltage waveform generation module, and the multi-channel high-voltage waveform generation module provides the required high-voltage signals for the multiple nozzles.

[0005] The main control module is used to output array control signals according to the printing process and printing control timing requirements, control the corresponding high-voltage waveform generation module to output multi-order high-voltage pulse waves, and realize independent on-off control of each nozzle; the control signal includes n-channel PWM pulse control signals, each PWM pulse control signal includes a DC high-voltage control signal and a pulse wave control signal, the n-channel pulse wave control signals are used to control the order, duty cycle and frequency of the multi-order high-voltage pulse waves, and the n-channel DC high-voltage control signals are used to control the size of each order of high-voltage signals in the multi-order high-voltage pulse waves.

[0006] The array-type high-voltage generation and control system provided in this application is suitable for EHD type nozzles. It adopts a multi-channel high-voltage waveform generation module, and independently controls each high-voltage waveform output module through the array control signal output by the main control module. The high-voltage waveform output module provides the required high-voltage signal for each nozzle, which can realize independent on-off control of each nozzle in the multi-nozzle EHD type.

[0007] As a further preferred embodiment, the single-channel high-voltage waveform generation module includes n-channel gate voltage forming circuits, n-step high-voltage PWM generation circuits and n-channel boost circuits;

[0008] The n-way gate voltage forming circuit is used to convert the n-way pulse wave control signals into n-way gate control signals; the n-way boost circuit is used to generate n-way DC high-voltage signals of the required magnitude according to the n-way DC high-voltage control signals, and load them as bias voltage signals on the bias terminals corresponding to the n-order high-voltage PWM generation circuit; the n-order high-voltage PWM generation circuit is used to output multi-order high-voltage pulse waves according to the gate control signals under the action of the n-way bias voltage signals.

[0009] As a further preferred embodiment, the boost circuit adopts a multi-stage boost boost circuit, and the DC high voltage generated by the multi-stage boost boost circuit is determined by the boost ratio in each stage of the BOOS boost circuit, and the boost ratio in each stage of the BOOS boost circuit is adjusted by the frequency and duty cycle of the corresponding DC high voltage control signal.

[0010] As a further preferred embodiment, the boost circuit adopts a flyback boost circuit, and the DC high voltage generated by the flyback boost circuit is determined by the duty cycle of the corresponding DC high voltage control signal and the turns ratio of the transformer in the flyback boost circuit.

[0011] As a further preferred embodiment, each high-voltage waveform generating module further includes n first ADC conversion circuits;

[0012] The n-way first ADC conversion circuits are used to collect the output voltages of the n-way boost circuits and feed them back to the main control module; the main control module is used to control the output voltages of the n-way boost circuits through a negative feedback algorithm.

[0013] As a further preference, the n-order high-voltage PWM generation circuit is a second-order high-voltage PWM generation circuit or a third-order high-voltage PWM generation circuit.

[0014] As a further preferred embodiment, the second-order high-voltage PWM generation circuit includes a first switching tube and a second switching tube;

[0015] The gate of the first switching tube receives the pulse wave control signal in the first PWM pulse control signal, and the drain of the first switching tube receives the DC high-voltage control signal in the first PWM pulse control signal through the first resistor; the gate of the second switching tube receives the pulse wave control signal in the second PWM pulse control signal, and the source of the second switching tube receives the DC high-voltage control signal in the second PWM pulse control signal; the source of the first switching tube, the drain of the second switching tube and the corresponding nozzle are connected together to form a load circuit.

[0016] As a further preferred embodiment, the third-order high-voltage PWM generation circuit includes a third switching tube, a fourth switching tube and a fifth switching tube;

[0017] The gate of the third switching tube receives the pulse wave control signal in the first PWM pulse control signal, and the drain of the third switching tube receives the DC high-voltage control signal in the first PWM pulse control signal through the second resistor; the gate of the fourth switching tube receives the pulse wave control signal in the second PWM pulse control signal, and the source of the fourth switching tube receives the DC high-voltage control signal in the second PWM pulse control signal; the gate of the fifth switching tube receives the pulse wave control signal in the second PWM pulse control signal, and the drain of the fifth switching tube receives the DC high-voltage control signal in the second PWM pulse control signal through the third resistor; the source of the third switching tube, the drain of the fourth switching tube, the source of the fifth switching tube and the corresponding nozzle are connected together to form a load circuit.

[0018] As a further preferred embodiment, each high-voltage waveform generating module further includes a high-voltage output protection circuit, wherein the high-voltage output protection circuit includes a high-voltage isolator and a second ADC conversion circuit;

[0019] The high-voltage isolator is used to collect the load loop voltage; the second ADC conversion circuit is used to convert the load loop voltage into a digital signal and send it to the main control module; the main control module is used to determine whether it exceeds the overload threshold value based on the digital signal, and control the on and off of the corresponding switch tube and the power supply of the DC high-voltage control signal based on the judgment result.

[0020] As a further preference, the gate voltage forming circuit adopts a half-bridge circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of an array-type high-pressure generation control system applicable to EHD type sprinklers provided in this application;

[0022] Figure 2 This is a diagram showing the connection relationship between the circuits in the single-channel high-voltage waveform generation module provided in an embodiment of the present application;

[0023] Figure 3 It is a cascade diagram of a multi-stage boost circuit provided in an embodiment of the present application;

[0024] Figure 4 1 is a circuit diagram of a single-stage boost circuit provided in an embodiment of the present application;

[0025] Figure 5 yes Figure 4 The control timing diagram of the single-stage boost circuit provided;

[0026] Figure 6 is a circuit diagram of a flyback boost circuit provided in an embodiment of the present application;

[0027] Figure 7 is a circuit diagram of a second-order high-voltage PWM generation circuit provided in an embodiment of the present application;

[0028] Figure 8 yes Figure 7 The control timing diagram of the second-order high-voltage PWM generation circuit provided;

[0029] Figure 9 is a circuit diagram of a third-order high-voltage PWM generation circuit provided in an embodiment of the present application;

[0030] Figure 10 yes Figure 9 The control timing diagram of the third-order high-voltage PWM generation circuit is provided;

[0031] Figure 11 This is a schematic diagram of a high-voltage output protection circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0033] It should be understood that, in the description of this application, the term "several" means at least one, such as one, two, etc., unless otherwise clearly and specifically defined; the term "plurality" means two or more, unless otherwise clearly and specifically defined; the terms "first" and "second" etc. are used to distinguish different objects, rather than to describe a specific order of objects; the term "and / or" includes any and all combinations of one or more related listed items.

[0034] Additionally, references throughout this specification to "one embodiment," "one embodiment," "an example," or similar language indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, appearances of the phrase "in one embodiment," "in one embodiment," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0035] The present application provides an array type high pressure generation control system suitable for an EHD type nozzle, wherein the EHD type nozzle comprises a plurality of nozzles arranged in an array, such as Figure 1As shown, the array-type high-voltage generation and control system provided in this embodiment includes a main control module 10 and multiple high-voltage waveform generation modules 20. The main control module 10 independently controls each high-voltage waveform generation module 20. The high-voltage waveform generation modules are isolated from each other, for example, by spacing isolation of PCB boards, hollowing out or metal shielding covers, to ensure that the modules are not interfered with each other.

[0036] The main control module 10 can be a control chip commonly used in the art, such as an MCU, DSP, or FPGA. It is used to output array control signals through the chip's IO port according to the printing process and print control timing requirements, controlling the corresponding high-voltage waveform generation module to output multi-stage high-voltage pulse waves, providing corresponding high-voltage signals for the nozzles currently required for printing, and achieving independent on-off control of each nozzle. For example, if a single nozzle or several nozzles need to print or stop printing at a certain time, the high-voltage waveform generation module corresponding to the nozzle is individually controlled to output the required high-voltage signal, while other high-voltage waveform generation modules do not output high-voltage signals.

[0037] It should be noted that the printing process requirements provided in this embodiment are configured based on parameters such as the viscosity and conductivity of the printing ink to control the number of orders and the magnitude of each order of high-voltage signal in the multi-order high-voltage pulse waves output by each high-voltage waveform generation module. The printing control timing requirements provided in this embodiment are configured based on the desired printing pattern, including the start and stop times of each nozzle and the duration of operation, to control the duty cycle and frequency of the multi-order high-voltage pulse waves output by each high-voltage waveform generation module.

[0038] Specifically, the control signal output by the main control module 10 provided in this embodiment includes n-way PWM pulse control signals, each PWM pulse control signal includes a DC high-voltage control signal and a pulse wave control signal, the n-way pulse wave control signals are used to control the order, duty cycle and frequency of the multi-order high-voltage pulse wave, and the n-way DC high-voltage control signals are used to control the size of each order of high-voltage signals in the multi-order high-voltage pulse wave.

[0039] The array-type high-voltage generation and control system provided in this embodiment is suitable for EHD type nozzles. It adopts a multi-channel high-voltage waveform generation module, and independently controls each high-voltage waveform output module through the array control signal output by the main control module. The high-voltage waveform output module provides the required high-voltage signal for each nozzle, which can realize independent on-off control of each nozzle in the multi-nozzle EHD type.

[0040] In one embodiment, Figure 2 As shown, the single-channel high-voltage waveform generation module provided by the present application may include n-channel gate voltage forming circuits 21 , n-step high-voltage PWM generation circuits 22 and n-channel boost circuits 23 .

[0041] The n-way gate voltage forming circuit is used to convert the n-way pulse wave control signals in the control signal into the n-way gate control signals required by the back-end n-stage high-voltage PWM generating circuit. Specifically, the gate voltage forming circuit provided in this embodiment can adopt a half-bridge circuit.

[0042] The n-channel boost circuit is used to convert the low-voltage DC signal into a DC high voltage of a required magnitude according to the n-channel DC high-voltage control signals in the control signal, and load it as a bias voltage on the bias terminal corresponding to the n-order high-voltage PWM generation circuit.

[0043] Furthermore, the single-channel high-voltage waveform generation module provided by the present application may also include n-channel ADC conversion circuits. The n-channel ADC conversion circuits correspondingly collect the output voltages of the n-channel boost circuits and feed them back to the control chip, which uses a negative feedback algorithm to achieve precise control of the output voltages of the n-channel boost circuits.

[0044] Specifically, the single-channel boost circuit provided in this embodiment may adopt a multi-stage boost circuit or a flyback boost circuit.

[0045] like Figure 3 As shown in the figure, the operating principle of using a multi-stage boost circuit to output high-voltage DC is as follows: a low-voltage DC signal VIN is output through a single boost circuit, resulting in an output voltage HV1 = VIN * N1. Similarly, HVOUT = VIN * N1 * N2 .... * Np, where N1 to Np are the boost ratios of the cascaded boost circuits, ultimately boosting the voltage to a specified level. For high-voltage power supplies, the output voltage can be modified by adjusting the boost ratios of different boost stages.

[0046] Figure 4 The circuit diagram of the single-stage boost circuit provided by the embodiment of the present application mainly includes a transistor M3, a transistor M4, an inductor L2, and capacitors C9 and C10. The working principle of the boost circuit provided by this embodiment is as follows: First, the control chip sets the frequency and duty cycle of PWM_CTR_H and PWM_CTR_L, and then outputs a differential PWM signal, such as Figure 5 As shown; when PWM_CTR_H is set high and PWM_CTR_H is set low, inductor L2 will store energy, and capacitors C9 / C10 will provide the required current to the back-end n-stage high-voltage PWM generation circuit; when PWM_CTR_H is set low and PWM_CTR_H is set high, inductor L2 will charge capacitors C9 / C10 and the current required by the back-end n-stage high-voltage PWM generation circuit.

[0047] According to the volt-second method, the output voltage H of the boost circuit is VOUT =V IN / (1-D), where D is the duty cycle of PWM_CTR_H, i.e., Ton / T. Therefore, by changing D, the boost ratio N of the boost circuit can be changed, thereby controlling the output voltage of each boost circuit stage. Figure 4 The control chip obtains the output voltage of the boost circuit at this level from the ADC conversion circuit, and performs precise closed-loop control through a negative feedback algorithm.

[0048] The difference between this embodiment using a flyback boost circuit to output high voltage DC and the aforementioned multi-stage boost circuit is that it uses a voltage isolation method to prevent the output high voltage signal from crosstalking with the input low voltage DC signal. Figure 6 As shown, the flyback boost circuit provided in this embodiment mainly includes a transformer T3, a switch tube M5, a capacitor C12, a resistor R4 and a diode D1.

[0049] The flyback boost circuit provided in this embodiment operates as follows: after a low-voltage DC signal VIN is input, it is connected to the drain of the switch tube M5 through the primary side of the transformer T3. The capacitor C12, the resistor R4, and the diode D1 form an absorption circuit to prevent the switch tube M5 from experiencing overvoltage during switching. When the switch tube M5 is in the on state, the primary side of the transformer T3 is in an energy storage state. Since the secondary coil is out of phase with the primary coil, no current flows through it. The output voltage HVOUT of the boost circuit is supplied by the capacitor on the secondary side. When the switch tube M5 is in the off state, the magnetic field disappears, causing the primary voltage electrode to flip, and the diode D3 to turn on. The secondary side of the transformer T3 charges the capacitor and supplies the current required by the back-end n-order high-voltage PWM generation circuit.

[0050] The output voltage HVout of the flyback boost circuit provided in this embodiment is expressed as: As can be seen from the expression, the output voltage of the flyback boost circuit depends on the transformer's turns ratio N2 / N1 and the duty cycle D. The duty cycle is controlled by the control chip through the PWM_CTR pin. The output voltage is controlled by the voltage signal collected by the ADC conversion circuit and a negative feedback algorithm to ensure its output accuracy.

[0051] In one embodiment, due to the different parameter designs of inks with different viscosities and nozzles with different apertures, the drag force required for printing is different. Therefore, the n-order high-voltage PWM generation circuit provided in this application is mainly a second-order high-voltage PWM generation circuit or a third-order high-voltage PWM generation circuit.

[0052] When the n-order high-voltage PWM generation circuit is a second-order high-voltage PWM generation circuit, the control signal received by the second-order high-voltage PWM generation circuit is two control signals, wherein the pulse wave control signal in one control signal is HV_control+, and the DC high-voltage step one voltage is HV_A; the pulse wave control signal in the other control signal is HV_control-, and the DC high-voltage step two voltage is HV_B.

[0053] Specifically, if Figure 7 As shown, the second-order high-voltage PWM generation circuit provided in this embodiment includes a first switch M6 and a second switch M7. The connections between these components are as follows: the gate of the first switch M6 receives HV_control+, and the drain of the first switch M6 receives HV_A via a first resistor R7; the gate of the second switch M7 receives HV_control-, and the source of the second switch M7 receives HV_B; the source of the first switch M6, the drain of the second switch M7, and the corresponding nozzle are connected together to form a load circuit.

[0054] Figure 8 This is a second-order pulse waveform diagram output by the second-order high-voltage PWM generating circuit provided in this embodiment, such as Figure 8 As shown, the waveform has a DC bias voltage HV_B, and the high voltage level is HV_A. Its frequency, duty cycle, and the corresponding values ​​of HV_A and HV_B can all be set. Figure 7 The half-bridge switch tube of the second-order high-voltage PWM generation circuit shown in the figure can be controlled by controlling the on and off of the switch tubes M6 and M7 through the input of the control signal. Figure 8 The high voltage PWM output status is shown.

[0055] Specifically, in Figure 8 In the initial time, the input high voltage is set to HV_B, and its voltage value is set by the software corresponding to the boost / flyback type boost circuit mentioned above. Figure 7 As shown in the figure, the M7 switch is turned on and the M6 ​​switch is turned off. At this time, the high voltage signal of HV_B enters the HV_PWM_OUT pin. When the next switching conversion cycle comes, M6 is turned on and M7 is turned off. The high voltage of HV_A enters the HV_PWM_OUT pin, and then the output time of the HV_control+ / HV_control- signal described above is controlled by software to achieve control. Figure 8 The Ton time shown in the figure, the entire switching period T is also controlled by the HV_control+ / HV_control- signal controlled by the software, thereby achieving the purpose of adjusting the duty cycle and switching frequency. Figure 7The adjustment of the corresponding resistors R8, R9, and R7 can achieve the purpose of the PWM switching cycle rise time, thereby optimizing the process parameters for some inks with different viscosities.

[0056] When the n-order high-voltage PWM generation circuit is a three-order high-voltage PWM generation circuit, the control signals received by the three-order high-voltage PWM generation circuit are three control signals, the pulse wave control signal in the first control signal is HV_A_control+, and the DC high-voltage step one voltage is VCC_HV_A, the pulse wave control signal in the second control signal is HV_B_control+, and the DC high-voltage step two voltage is VCC_HV_B, and the pulse wave control signal in the third control signal is HV_C_control+, and the DC high-voltage step three voltage is VCC_HV_C.

[0057] Specifically, if Figure 9 As shown, the third-order high-voltage PWM generation circuit provided in this embodiment includes a third switch Q1, a fourth switch Q2, and a fifth switch Q3. The connections between these components are as follows: the gate of the third switch Q1 receives HV_A_control+, and the drain of the fifth switch Q3 receives VCC_HV_A via a second resistor R1; the gate of the fourth switch Q2 receives HV_B_control+, and the source of the fourth switch Q2 receives VCC_HV_B; the gate of the fifth switch Q3 receives HV_C_control+, and the drain of the fifth switch Q3 receives VCC_HV_C via a third resistor R478; the source of the third switch Q1, the drain of the fourth switch Q2, the source of the fifth switch Q3, and the corresponding nozzles are connected together to form a load circuit.

[0058] For circuits that need to output third-order high-voltage pulse waves, such as Figure 9 As shown, it is compatible with the second-order pulse wave output circuit; Figure 9 In the initial time, the input high voltage is set to VCC_HV_B, and its voltage value is set by the software corresponding to the boost / flyback type boost circuit mentioned above. Figure 9 As shown in the figure, the Q2 switch tube is turned on and the Q1 / Q3 switch tube is turned off. At this time, the high-voltage signal of VCC_HV_B enters the HV_OUTPUT+ pin. When the next switching conversion cycle comes, Q1 is turned on, Q2 / Q3 is turned off, and the high-voltage of VCC_HV_A enters the HV_OUTPUT+ pin. When the next switching conversion cycle comes, Q3 is turned on, Q1 / Q2 is turned off, and the high-voltage of VCC_HV_C enters the HV_OUTPUT+ pin. For the duty cycle corresponding to the required control, the output time of the HV_A_control+ / HV_B_control+ / HV_C_control+ signal described above is controlled by software to achieve control. Figure 10 The Ton time shown in the figure, the entire switching period T is also controlled by the software control HV_A_control+ / HV_B_control+ / HV_C_control+ signals to achieve the purpose of adjusting the duty cycle and switching frequency. Figure 9 The corresponding resistors R1, R478 and the base input resistance of each switch tube can be adjusted to achieve the purpose of PWM switching cycle rise time, so that the process parameters can be optimized for some inks with different viscosities. Figure 10 As shown, the switching time of the Q1\Q2\Q3 switch tubes is controlled respectively, and the corresponding conduction time T1\T2\T3 is controlled by the control chip to achieve adjustable duty cycle and frequency.

[0059] In one embodiment, the array-type high-voltage generation and control system provided by the present application further includes a high-voltage output protection circuit for preventing damage to the load end, resulting in a short circuit and damaging related circuits.

[0060] Specifically, if Figure 11 As shown, the high-voltage output protection circuit provided in this embodiment may include a high-voltage isolator and an ADC conversion circuit. The high-voltage isolator is used to collect the load circuit voltage. The ADC conversion circuit is used to convert the load circuit voltage into a digital signal and transmit it to the control chip. The control chip is used to determine whether the digital signal exceeds the overload threshold value based on the digital signal and, based on the determination result, control the on / off of the corresponding switch and the supply of the DC high-voltage control signal.

[0061] The working principle of the high-voltage output protection circuit provided in this embodiment is as follows: when the switch tube Q1 is turned on, the load loop current flows through the resistor R1, and the corresponding voltage is collected as a voltage variable through the high-voltage isolator and enters the ADC conversion circuit. The ADC conversion circuit converts it into a digital signal and sends it to the control chip in real time via the communication bus. The control chip determines whether it exceeds the overload threshold value and thus determines whether to shut down the power supply of Q1 and the high-voltage VCC_HV_A. It can also report the corresponding fault to other modules for easy maintenance.

[0062] It is easy for those skilled in the art to understand that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. An array-type high-pressure generation control system suitable for an EHD type nozzle, wherein the EHD type nozzle comprises a plurality of nozzles arranged in an array, characterized in that: The array-type high-voltage generation control system includes a main control module and a multi-channel high-voltage waveform generation module. The main control module independently controls each high-voltage waveform generation module, and the multi-channel high-voltage waveform generation module provides the required high-voltage signals for multiple nozzles. The main control module is used to output array control signals according to the printing process and printing control timing requirements, control the corresponding high-voltage waveform generation module to output multi-stage high-voltage pulse waves, and realize independent on-off control of each nozzle; the control signal includes n PWM pulse control signals, each PWM pulse control signal includes a DC high voltage control signal and a pulse wave control signal. n The pulse wave control signal is used to control the order, duty cycle and frequency of the multi-stage high-voltage pulse wave. n The DC high voltage control signal is used to control the magnitude of each order of high voltage signal in the multi-order high voltage pulse wave; Single-channel high voltage waveform generation module includes n Gate voltage forming circuit, n Step high voltage PWM generation circuit and n Boost circuit; n The gate voltage forming circuit is used to n The pulse wave control signal is converted into n Road gate control signal; n The boost circuit is used to correspond to the n DC high voltage control signal generation n The DC high voltage signal of the required size is loaded on the n The bias terminal corresponding to the high-voltage PWM generating circuit; n The high-voltage PWM generator circuit is used to n Under the action of the circuit bias voltage signal, a multi-stage high-voltage pulse wave is output according to the gate control signal.

2. The array type high pressure generation control system suitable for EHD type nozzles according to claim 1, characterized in that: The boost circuit adopts a multi-stage boost circuit. The DC high voltage generated by the multi-stage boost circuit is determined by the boost ratio of each stage of the BOOS boost circuit. The boost ratio of each stage of the BOOS boost circuit is adjusted by the frequency and duty cycle of the corresponding DC high voltage control signal.

3. The array type high pressure generation control system suitable for EHD type nozzles according to claim 1, characterized in that: The boost circuit adopts a flyback boost circuit. The DC high voltage generated by the flyback boost circuit is determined by the duty cycle of the corresponding DC high voltage control signal and the turns ratio of the transformer in the flyback boost circuit.

4. The array type high pressure generation control system suitable for EHD type nozzles according to claim 1, characterized in that: Each high voltage waveform generation module also includes n a first ADC conversion circuit; n The first ADC conversion circuit is used for corresponding acquisition n The output voltage of the boost circuit is fed back to the main control module; the main control module is used to realize the negative feedback algorithm n The output voltage of the boost circuit is controlled.

5. The array type high pressure generation control system suitable for EHD type nozzles according to claim 1, characterized in that: described n The first-order high-voltage PWM generating circuit is a second-order high-voltage PWM generating circuit or a third-order high-voltage PWM generating circuit.

6. The array type high pressure generation control system suitable for EHD type nozzles according to claim 5, characterized in that: The second-order high-voltage PWM generation circuit includes a first switching tube and a second switching tube; The gate of the first switching tube receives the pulse wave control signal in the first PWM pulse control signal, and the drain of the first switching tube receives the DC high-voltage control signal in the first PWM pulse control signal through the first resistor; the gate of the second switching tube receives the pulse wave control signal in the second PWM pulse control signal, and the source of the second switching tube receives the DC high-voltage control signal in the second PWM pulse control signal; the source of the first switching tube, the drain of the second switching tube and the corresponding nozzle are connected together to form a load circuit.

7. The array type high pressure generation control system suitable for EHD type nozzles according to claim 5, characterized in that: The three-stage high-voltage PWM generation circuit includes a third switch tube, a fourth switch tube and a fifth switch tube; The gate of the third switching tube receives the pulse wave control signal in the first PWM pulse control signal, and the drain of the third switching tube receives the DC high-voltage control signal in the first PWM pulse control signal through the second resistor; the gate of the fourth switching tube receives the pulse wave control signal in the second PWM pulse control signal, and the source of the fourth switching tube receives the DC high-voltage control signal in the second PWM pulse control signal; the gate of the fifth switching tube receives the pulse wave control signal in the second PWM pulse control signal, and the drain of the fifth switching tube receives the DC high-voltage control signal in the second PWM pulse control signal through the third resistor; the source of the third switching tube, the drain of the fourth switching tube, the source of the fifth switching tube and the corresponding nozzle are connected together to form a load circuit.

8. The array type high pressure generation control system suitable for EHD type nozzles according to claim 6 or 7, characterized in that: Each high-voltage waveform generation module further includes a high-voltage output protection circuit, which includes a high-voltage isolator and a second ADC conversion circuit; The high-voltage isolator is used to collect the load loop voltage; the second ADC conversion circuit is used to convert the load loop voltage into a digital signal and send it to the main control module; the main control module is used to determine whether it exceeds the overload threshold value based on the digital signal, and control the on and off of the corresponding switch tube and the power supply of the DC high-voltage control signal based on the judgment result.

9. The array type high pressure generation control system suitable for EHD type nozzles according to claim 1, characterized in that: The gate voltage forming circuit adopts a half-bridge circuit.

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