Digital hydraulic servo valve controller

Abstract

The utility model relates to the technical field of hydraulic servo valve control, in particular to a digital hydraulic servo valve controller. The controller comprises a core processing unit, an analog input signal conditioning circuit, an IO interface circuit, a relay switching module and a servo valve driving circuit. The core processing unit is internally provided with an embedded processor and is responsible for A / D conversion, D / A conversion, parameter storage, communication, control and state presentation. The analog input signal conditioning circuit is responsible for inputting a sensor signal and a given value setting signal. The IO interface circuit is responsible for receiving a setting signal and a switching control signal. And the relay switching module is responsible for switching a control signal source. The servo valve drive circuit receives the servo control signal and outputs drive current to control the hydraulic servo valve to work. The multi-path servo valve control system has the advantages of settable control parameters, convenience in debugging, high control precision, low cost and the like, multi-path servo valve control can be realized, and system wiring is simplified.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic servo valve control, in particular to a digital hydraulic servo valve controller. Background Art

[0002] As the core component of hydraulic servo control system, the importance of hydraulic servo valve is self-evident. It is widely used in many key fields such as aviation, aerospace, shipbuilding, metallurgy, chemical industry, etc., providing strong technical support for the development of these fields.

[0003] The main function of a hydraulic servo valve is to receive and respond to control signals to adjust the flow rate and direction of the hydraulic oil. Specifically, the input control signal of a hydraulic servo valve is usually a current signal. When the control current flows through the servo valve, it accurately controls the flow rate and direction of the hydraulic oil according to the magnitude and direction of the current. This control process is proportional to the control current of the servo valve, allowing the hydraulic servo valve to achieve precise control of the hydraulic system.

[0004] After receiving the control current signal, the servo valve can accurately control the output of hydraulic oil of corresponding flow and direction through its internal complex mechanical structure and electromagnetic principle. The hydraulic oil then passes through different actuators, such as hydraulic motors and hydraulic cylinders, to achieve precise control of physical quantities such as force, displacement, and angle. This control method enables the hydraulic servo system to accurately track and control various complex motion trajectories and dynamic processes.

[0005] However, most traditional hydraulic servo valve controllers are analog controllers, which have certain limitations in function and use. First, the functions of analog controllers are relatively simple and can only realize basic control functions, which cannot meet the requirements of modern industry for complex control needs. Secondly, the adjustment parameters of analog controllers are inconvenient, and usually require manual adjustment of analog circuit parameters. The adjustment process is cumbersome and complicated, which is not conducive to improving production efficiency. In addition, analog controllers are large in size and occupy more space, which is not conducive to equipment integration and installation. Finally, the debugging workload of analog controllers is large, and professional technicians are required to perform long-term debugging and optimization, which increases production costs and time costs. Utility Model Content

[0006] In view of the deficiencies in the prior art, the utility model discloses a digital hydraulic servo valve controller for solving the problems that traditional hydraulic servo valve controllers are mostly analog controllers with single functions, inconvenient parameter adjustment, large controller size and heavy debugging workload.

[0007] The utility model is realized through the following technical solutions:

[0008] The utility model provides a digital hydraulic servo valve controller, comprising:

[0009] The core processing unit, which has a built-in embedded processor, is responsible for A / D conversion, D / A conversion, parameter storage, communication, control and status presentation;

[0010] Analog input signal conditioning circuit, responsible for inputting sensor signals and given value setting signals to the core processing unit and data acquisition card port;

[0011] The IO interface circuit is responsible for receiving setting signals and switching control signals.

[0012] The relay switching module receives the D / A control signal sent by the core processing unit, receives the D / A signal input from the port of the data acquisition card, and outputs a servo control signal at the same time;

[0013] The servo valve driving circuit receives the servo control signal and outputs a driving current through a level conversion circuit and a voltage-controlled current source to control the hydraulic servo valve to perform corresponding operations.

[0014] Furthermore, the core processing unit is integrated with:

[0015] A / D converter and D / A converter are responsible for collecting analog signals and outputting four-channel analog voltage signals;

[0016] EEPROM memory, responsible for storing the control parameters of the controller;

[0017] The communication interface circuit adopts RS485 communication interface and Modbus RTU communication protocol to perform two-way RS485 communication.

[0018] Furthermore, the two RS485 communication channels of the communication interface circuit are used for configuring control parameters, and the other channel is connected to a display for displaying the status and parameters of the controller.

[0019] Furthermore, the data acquisition card port is a DB25 data acquisition card port, which is responsible for connecting to the host computer acquisition card and transmitting the analog input signal and the D / A signal of the host computer.

[0020] Furthermore, the input signal of the analog input signal conditioning circuit is a 4-20mA current signal or a 0-5V voltage signal.

[0021] Furthermore, the IO interface circuit receives switch input signals from the controller working mode setting switch and the switching switch of the four-way servo valve control rights, and outputs control signals of the relay switching module.

[0022] Furthermore, when the control signal received by the relay switching module is at a low level, the relay switch is normally open, and the servo valve is controlled by the control signal output by the core processing unit;

[0023] When the control signal received by the relay switching module is at a high level, the relay switch is normally closed, and the servo valve is controlled by the D / A signal input from the port of the data acquisition card.

[0024] Furthermore, in the servo valve driving circuit, the level conversion circuit is responsible for converting the D / A signal with an amplitude of 0-2.5V output by the core processing unit to -10V~+10V.

[0025] Furthermore, in the servo valve drive circuit, the voltage-controlled current source is responsible for linearly converting a voltage signal of -10V to +10V into a current signal of -40mA to +40mA.

[0026] Furthermore, the embedded processor is a STM32H750VBT6 processor.

[0027] The beneficial effects of the utility model are:

[0028] This utility model hydraulic servo valve controller uses advanced digital control technology and has flexible and adjustable control parameter settings, which greatly facilitates the debugging process. At the same time, its control accuracy is as high as the industry-leading level, and the cost is relatively low, providing users with a cost-effective solution.

[0029] In addition, the controller has multi-channel driving capabilities and can drive four hydraulic servo valves at the same time, and realize the coordinated control of multiple servo valves through a control board. By connecting different feedback physical quantities, the controller can flexibly realize the functional requirements of various hydraulic systems, including but not limited to precise regulation of key parameters such as force control, rotation angle, displacement, and flow.

[0030] To further optimize system performance, the controller is also equipped with signal conditioning circuits, control relay switching circuits, and DB25 data acquisition card ports. The application of these advanced technologies enables the entire control system including the hydraulic servo valve to have higher configuration flexibility, while effectively reducing the number of system wiring and significantly reducing the wiring workload, bringing users a more convenient and efficient experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a structural block diagram of a digital hydraulic servo valve controller;

[0033] Figure 2 This is a schematic diagram of a relay switching circuit in an embodiment of the utility model;

[0034] Figure 3 This is a schematic diagram of a servo valve drive circuit according to an embodiment of the utility model;

[0035] Figure 4 It is a schematic diagram of port signal definition of DB25 data acquisition card in the embodiment of the utility model. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0037] In one embodiment, if Figure 1 As shown, a digital hydraulic servo valve controller is provided, and specifically, its core processing unit is composed of multiple key components such as an embedded processor, an A / D converter, a D / A converter, an EEPROM memory, and a communication interface. Among them, the embedded processor uses the STM32H750VBT6 model, whose main frequency is as high as 480 MHz and the computing power is 2.14DMIPS / MHz, which can fully meet the controller's demand for computing power.

[0038] As a preferred embodiment of the present invention, the processor integrates three 16-bit A / D converters and supports a maximum of 20 A / D channels, thereby achieving accurate acquisition of 12-channel analog signals in the control setting.

[0039] In terms of digital-to-analog conversion, the D / A converter uses the DAC8568 model, which integrates a 16-bit 8-channel voltage output digital-to-analog converter with a 2.5V voltage reference. Through DAC8568, four analog voltage signals can be output to meet the output requirements of the controller.

[0040] As for EEPROM memory, AT24C08 model is selected, which has a storage capacity of 1KB and is used to store the control parameters of the controller to ensure safe and reliable storage of the parameters.

[0041] In terms of communication, the core processing unit of this embodiment adopts Modbus RTU communication protocol, and realizes two-way RS485 communication through interface chip SP3485E for configuring control parameters. At the same time, another communication is connected to the display to display the status and parameters of the controller in real time, which is convenient for users to monitor and manage.

[0042] Therefore, the design of the core processing unit of this embodiment fully considers multiple aspects such as computing power, data acquisition, digital-to-analog conversion, parameter storage and communication, ensuring that the controller can operate stably and reliably and meet the needs of practical applications.

[0043] In this embodiment, 12 analog input signal conditioning circuits are designed, which are mainly responsible for receiving and processing various input signals, wherein the input signals mainly include 4-20mA current signals and 0-5V voltage signals.

[0044] In order to ensure the accuracy and stability of the input signal, this embodiment adopts advanced analog input signal conditioning technology. These technologies can filter, amplify and linearize the input signal, thereby eliminating noise interference and improving the signal-to-noise ratio of the signal. At the same time, a high-precision analog-to-digital converter is also used to convert the analog signal into a digital signal for subsequent digital processing and control.

[0045] In addition to the analog input signal conditioning circuit, this embodiment also provides an IO input interface circuit. These circuits are mainly responsible for receiving switch input signals. The switch input signals mainly come from the controller's working mode setting switch and the four-way servo valve control right switching switch. Through these switches, the user can easily set the controller's working mode and switch the servo valve's control right, thereby achieving flexible control of the system.

[0046] The IO output circuit of this embodiment is responsible for outputting the control signals of the four-way switching relays. These control signals are generated according to the operating state and control strategy of the system and are used to control the switch state of the relays. By controlling the switch of the relays, the control right of the hydraulic servo valve can be switched, and a more flexible configuration function of the system can be realized.

[0047] In one embodiment, if Figure 2In the relay switching circuit shown, when the IO_OUT signal output by the core board microprocessor is in a low level state, the transistor T1 will be turned on, and the coil of the relay K1 will be energized and attracted, thereby causing the normally open contact of K1 to close. This process realizes the connection of the voltage signal H_DA output by the core board D / A to S_CTRL, and then the S_CTRL signal is input to the servo valve drive circuit, thereby realizing the control of the servo valve by the core board CPU. Conversely, when the IO_OUT signal is converted to the main level, the normally closed contact of K1 will be closed, and the upper computer D / A signal AUTO_CTRL from the DB25 interface will be connected to S_CTRL, thereby realizing the control of the servo valve by the upper computer.

[0048] In one embodiment, if Figure 3 As shown in the figure, the servo valve drive circuit consists of two main parts: a level conversion circuit and a voltage-controlled current source. Figure 3 V+2.5V in the figure indicates the 2.5V reference voltage output by DAC8568. The D / A signal DAC output by the core board has an amplitude range of 0 to 2.5V. After being processed by the level conversion circuit, it is converted into a voltage range of -10V to +10V and output by op amp 1.

[0049] As a preferred embodiment of this invention, Figure 3 In the figure, op amp 2, op amp 3, and op amp 4 together constitute the voltage-controlled current source part. Among them, op amp 2 is a follower, and its input signal comes from S_CTRL output by the relay switching circuit. Op amp 3 and op amp 4 together realize the linear conversion function of voltage and current, and can linearly convert the voltage signal from -10V to +10V into the current signal from -40mA to +40mA, thereby meeting the driving current requirements of common servo valves.

[0050] In one embodiment, if Figure 4 As shown in the figure, the DB25 data acquisition card port is selected, which can be connected to the host computer acquisition card to achieve stable transmission of analog input signals and D / A signals of the host computer. In the distributed measurement and control system composed of industrial computers or PLCs, this interface can facilitate the flexible configuration of the servo control system.

[0051] In one embodiment, the controller has two working modes, and the switching mode is realized through the IO_IN0 interface on the mainboard:

[0052] The first is the master control mode, in which the control right of the servo valve belongs to the core board CPU. The target signal of the controlled physical quantity is transmitted to the controller through the analog input channel. Then, the relay switching module transmits the D / A signal output by the core board to the servo valve drive circuit, and then the force, displacement, angle, flow and other physical quantities introduced by the analog input signal conditioning circuit are formed into a single closed-loop or double closed-loop control system to realize various complex control systems.

[0053] The second is the cooperative control mode, in which the control right of the servo valve is transferred to the host computer. At this time, the relay switching module is responsible for transmitting the D / A signal generated by the host computer introduced by the data acquisition card interface to the servo valve drive circuit, while the controller mainly plays the role of drive conversion, converting the D / A signal of the host computer into the current signal required by the servo valve, and the host computer realizes various complex control systems.

[0054] It should be noted that the two working modes have their own characteristics, and users can flexibly choose according to actual application requirements to achieve the best control configuration.

[0055] In summary, the utility model pressure servo valve controller uses advanced digital control technology and has flexible and adjustable control parameter settings, which greatly facilitates the debugging process and simplifies system wiring. At the same time, its control accuracy is as high as the industry-leading level, and the cost is relatively low, providing users with a cost-effective solution.

[0056] In addition, the controller has a strong driving capability and can drive four hydraulic servo valves at the same time, and realize the coordinated control of multiple servo valves through a control board. By connecting different feedback physical quantities, the controller can flexibly realize the functional requirements of various hydraulic systems, including but not limited to force control, rotation angle, displacement, pressure, flow and other key parameters.

[0057] To further optimize system performance, the controller is also equipped with signal conditioning circuits, control relay switching circuits, and DB25 data acquisition card ports. The application of these advanced technologies enables the entire control system including the hydraulic servo valve to have higher configuration flexibility, while effectively simplifying the system wiring process, significantly reducing the wiring workload, and bringing users a more convenient and efficient experience.

[0058] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A digital hydraulic servo valve controller, characterized in that: include: The core processing unit, which has a built-in embedded processor, is responsible for A / D conversion, D / A conversion, parameter storage, communication, control and status presentation; Analog input signal conditioning circuit, responsible for inputting sensor signals and given value setting signals to the core processing unit and data acquisition card port; IO interface circuit, responsible for receiving setting signals and switching control signals; The relay switching module receives the control signal sent by the core processing unit, receives the D / A signal input from the port of the data acquisition card, and outputs a servo control signal at the same time; The servo valve driving circuit receives the servo control signal and outputs a driving current through a level conversion circuit and a voltage-controlled current source to control the hydraulic servo valve to perform corresponding operations.

2. A digital hydraulic servo valve controller according to claim 1, characterized in that: The core processing unit is integrated with D / A converter, responsible for outputting four-channel analog voltage signals; EEPROM memory, responsible for storing the control parameters of the controller; The communication interface circuit adopts RS485 interface and Modbus RTU communication protocol to perform two-way RS485 communication.

3. A digital hydraulic servo valve controller according to claim 2, characterized in that: The communication interface circuit has two RS485 communication channels, one of which is responsible for configuring control parameters, and the other is connected to a display to display the status and parameters of the controller.

4. A digital hydraulic servo valve controller according to claim 1, characterized in that: The data acquisition card port is a DB25 data acquisition card port, which is responsible for connecting to the host computer acquisition card and transmitting the conditioned analog input signal and the D / A signal of the host computer.

5. A digital hydraulic servo valve controller according to claim 1, characterized in that: The input signal of the analog input signal conditioning circuit is a 4-20mA current signal or a 0-5V voltage signal.

6. A digital hydraulic servo valve controller according to claim 1, characterized in that: The IO interface circuit receives switch quantity input signals from the controller working mode setting switch and the switching switch of the four-way servo valve control right, and outputs control signals of the relay switching module at the same time.

7. A digital hydraulic servo valve controller according to claim 1, characterized in that: When the control signal received by the relay switching module is at a low level, the normally open contact of the relay is closed, and the control signal output by the core processing unit controls the servo valve; When the control signal received by the relay switching module is at a high level, the normally closed contact of the relay is closed, and the servo valve is controlled by the D / A signal input from the port of the data acquisition card.

8. A digital hydraulic servo valve controller according to claim 1, characterized in that: In the servo valve driving circuit, the level conversion circuit is responsible for converting the D / A signal with an amplitude of 0-2.5V output by the core processing unit to -10V~+10V.

9. A digital hydraulic servo valve controller according to claim 8, characterized in that: In the servo valve driving circuit, the voltage-controlled current source is responsible for linearly converting a voltage signal of -10V to +10V into a current signal of -40mA to +40mA.

10. A digital hydraulic servo valve controller according to claim 1, characterized in that: The embedded processor is an STM32H750VBT6 processor.

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