Can bus-based electronic control unit and control method

Abstract

Provided are a CAN bus-based electronic control unit and a control method. The electronic control unit comprises a CAN bus housing (1), an LVDT displacement sensor (2), proportional flow valves (3), and a main control circuit board (4). The LVDT displacement sensor (2), the proportional flow valves (3) and the main control circuit board (4) are installed in the CAN bus housing (1). The LVDT displacement sensor (2) and the control ends of the proportional flow valves (3) are respectively connected to the main control circuit board (4). Each proportional flow valve (3) comprises a moving iron (3.1), a push rod (3.2), and a basin-shaped pole shoe valve sleeve (3.3); the moving iron (3.1), the push rod (3.2), and the basin-shaped pole shoe valve sleeve (3.3) are coaxially arranged; one end of the push rod (3.2) is in contact with the moving iron (3.1), and the other end of the push rod (3.2) is inserted into the basin-shaped pole shoe valve sleeve (3.3); and the ends of the moving iron (3.1) and the push rod (3.2) contacting each other form a bowl-shaped structure.

Description

A CAN bus electronic control unit and control method Technical Field

[0001] The present invention relates to a CAN bus electronic control unit and a control method, belonging to the technical field of electronic control systems. Background Art

[0002] With the increasing application of electronic information technology in the field of hydraulic control, key components such as hydraulic valves are showing a trend of intelligent and digital development. As the core control component, the control accuracy and response speed of the electronic control unit have an important impact on the performance of the hydraulic valve. Based on the reliability and speed of CAN bus transmission, electronic control products integrated with CAN bus are gradually being put into market application.

[0003] To date, relevant foreign companies have launched mature CAN bus electronic control products, such as Thomas's EHA and Rexroth's CPM. The EHA electro-hydraulic actuator, developed by Thomas in Germany, integrates two conventional proportional pressure reducing valves for pilot pressure control of the controlled valves. It uses Hall effect sensors to detect valve spool displacement, achieving closed-loop control of the controlled valve spool displacement. The circuit board outputs control signals to drive the proportional pressure reducing valves and detects feedback signals from the displacement sensors based on demand. Pilot pressure control is achieved using conventional proportional pressure reducing valves, which have long response times due to performance limitations. The use of Hall effect sensors to detect valve spool displacement results in low accuracy, limiting the ability to achieve high-precision control of valve spool displacement. The CPM electronic control module, developed by Bosch Rexroth, uses a dual-coil proportional solenoid valve to control pilot pressure. However, these valves have a long axial dimension, restricting installation space and hindering overall valve volume reduction.

[0004] Summary of the Invention

[0005] In order to address the deficiencies of the prior art, the present invention aims to provide a CAN bus electronic control unit and a control method, which solve the problems of low integration, poor flexibility and low control accuracy in the prior art.

[0006] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0007] A CAN bus electronic control unit includes a CAN bus housing, an LVDT displacement sensor, a proportional flow valve and a main control circuit board.

[0008] The LVDT displacement sensor is a split structure, including a displacement sensor body and a displacement sensor transmitter circuit board. The displacement sensor body is connected to the displacement sensor transmitter circuit board through coil leads.

[0009] There are two proportional flow valves, which are symmetrically installed on both sides of the displacement sensor body;

[0010] The LVDT displacement sensor, proportional flow valve and main control circuit board are installed in the CAN bus housing. The displacement sensor transmitter circuit board and the control end of the proportional flow valve are connected to the main control circuit board respectively. The oil port end of the proportional flow valve is connected to the controlled element. The detection end of the displacement sensor body is connected to the valve core of the controlled element.

[0011] The proportional flow valve includes a moving iron, a push rod and a basin shoe valve sleeve. The moving iron, the push rod and the basin shoe valve sleeve are arranged coaxially. One end of the push rod contacts the moving iron, and the other end is inserted into the basin shoe valve sleeve.

[0012] Furthermore, the aforementioned proportional flow valve is a two-position three-way solenoid valve.

[0013] When the solenoid coil of the proportional flow valve is energized, the oil inlet P is connected to the working oil port A; when the solenoid coil of the proportional flow valve is de-energized, the oil return port T is connected to the working oil port A.

[0014] Furthermore, the contact end between the movable iron and the push rod is in a bowl-shaped structure.

[0015] Furthermore, the aforementioned CAN bus housing includes two parts: a CAN bus shell and a CAN bus end cover. One end face of the CAN bus shell is a mounting surface, on which a proportional flow valve mounting hole and a displacement sensor mounting hole are provided. The other end face of the CAN bus shell is provided with a circuit board mounting cavity, and the CAN bus end cover is fixedly connected to the CAN bus shell by screws.

[0016] Furthermore, a special-shaped sealing ring is provided between the aforementioned CAN bus end cover and the CAN bus housing.

[0017] Furthermore, the aforementioned displacement sensor body includes a coil, a skeleton, a pressure-bearing tube and an LVDT push rod. The skeleton is hollow and the tail is fixed to the CAN bus housing 1 by screws. An elastic part is provided at the top of the skeleton, and the lower end of the elastic part is connected to the LVDT push rod. The pressure-bearing tube is sleeved on the LVDT push rod. The coil 2.11 is wound on the outer ring of the skeleton using a two-segment three-wire winding method. The displacement sensor body is connected to the displacement sensor transmitter circuit board through the coil lead.

[0018] Furthermore, the aforementioned LVDT push rod includes a magnetic conductive section and a non-magnetic conductive section. One end of the non-magnetic conductive section is abutted against the end face of the valve core of the controlled element through an elastic member, and the other end is connected to the magnetic conductive section.

[0019] Furthermore, a sealing ring is provided between the aforementioned pressure-bearing pipe and the CAN bus housing.

[0020] Furthermore, the aforementioned main control circuit board includes a power module, an MCU control module, a drive module, a CAN communication module, an anti-interference module, and an over-voltage and under-voltage protection module;

[0021] The power module provides adjustable voltage to other modules.

[0022] The drive module outputs PWM signal to drive the proportional flow valve to operate.

[0023] The over-voltage and under-voltage protection module is connected to the output end of the power module to determine whether the output voltage of the power module is over-voltage or under-voltage, and disconnects the power module from other modules in the event of over-voltage or under-voltage, so as to improve the reliability of the circuit board.

[0024] The anti-interference module is located between the over-voltage and under-voltage protection module and the driving module, and is used to filter out the clutter generated by external electromagnetic interference on the voltage, thereby improving the operating stability of the driving module.

[0025] The CAN communication module realizes data interaction between modules in the main control circuit board (4), as well as information transmission between the main control circuit board (4) and external connectors. The MCU control module controls the coordinated actions of other modules and performs software programming according to user requirements.

[0026] Furthermore, the aforementioned also includes a connector and a connector adapter plate;

[0027] The plug-in connector is connected to the main control circuit board, and the plug-in connector adapter board is connected to the pins of the plug-in connector.

[0028] A CAN bus electronic control method comprises the following steps:

[0029] Control the action of the proportional solenoid valve in the CAN bus electronic control unit;

[0030] Obtain the valve core target displacement and actual displacement of the controlled element in the CAN bus electronic control unit;

[0031] Calculate the deviation err between the target displacement and the actual displacement and compare it with the preset deviation band Δerr;

[0032] If err>Δerr, any one of the proportional flow valves in the CAN bus electronic control unit is controlled to act alone, and then the deviation is adjusted through the single-acting deviation regulator Con1; otherwise, the two proportional flow valves in the CAN bus electronic control unit are controlled to act together, and then the deviation is adjusted using the double-acting deviation regulator Con2.

[0033] The beneficial effects achieved by the present invention are:

[0034] 1. The proportional flow valve integrates the push rod and valve core structure, the basin shoe and valve sleeve structure, the signal input end adopts a pin-type design, the contact surface between the moving iron and the push rod is designed in a bowl-shaped structure, and the push rod, that is, the valve core, is limited by the basin shoe valve sleeve, which is conducive to centering, with a small overall size and high integration;

[0035] 2. The LVDT displacement sensor adopts a two-stage structure, which reduces the axial size. The coil skeleton and the pressure tube are separated, which is easy to install.

[0036] 3. LVDT displacement sensor has higher displacement measurement accuracy than Hall displacement sensor. The two-position three-way proportional flow valve, main control circuit board and electronic control unit are more compact. Combined with the composite control method of pressure at both ends of the valve core, the valve core displacement control accuracy is higher.

[0037] 4. The whole system can be used as an independent electronic control module in conjunction with the controlled valve, with high flexibility in use;

[0038] 5. The main control circuit board includes power module, MCU control module, drive module, CAN communication module, anti-interference module, over-voltage and under-voltage protection module. It has programmable and fault diagnosis capabilities, is highly applicable, and can be used with various types of valves. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG1 is a schematic diagram of a CAN bus electronic control unit according to the present invention;

[0040] FIG2 is a structural diagram of a CAN bus electronic control unit according to the present invention;

[0041] FIG3 is a cross-sectional view of the structure of the CAN bus electronic control unit of the present invention;

[0042] FIG4 is a structural diagram of the LVDT displacement sensor of the present invention;

[0043] FIG5 is a cross-sectional view of the proportional flow valve structure of the present invention;

[0044] FIG6 is a connection diagram of the main control circuit board module of the present invention;

[0045] FIG7 is a block diagram of the composite control method of the present invention;

[0046] FIG8 is a control flow chart of the composite regulator of the present invention.

[0047] The meanings of the reference numerals in the figure are: 1-CAN bus housing; 1.1-CAN bus shell; 1.2-CAN bus end cover; 1.3-special-shaped sealing ring; 2-LVDT displacement sensor; 2.1-displacement sensor body; 2.2-displacement sensor transmitter circuit board; 2.11-coil; 2.12-skeleton; 2.13-pressure-bearing pipe; 2.14-elastic part; 2.15-LVDT push rod; 2.16-second sealing ring; 3-proportional flow valve; 3.1-moving iron; 3.2-push rod; 3.3-basin shoe valve sleeve; 4-main control circuit board; 5-connector; 6-connector adapter plate. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. Unless there is a conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0049] As shown in FIG1 , this embodiment discloses a CAN bus electronic control unit. The electronic control unit can be fixed to the outside of a controlled valve by screws, or connected to the controlled valve by a transition block. As shown in FIG1 , the electronic control unit specifically includes: a CAN bus housing 1, an LVDT displacement sensor 2, a proportional flow valve 3, a main control circuit board 4, a connector 5, and a connector adapter plate 6.

[0050] 3 , the CAN bus housing 1 comprises a CAN bus housing 1.1 and a CAN bus end cover 1.2. One end face of the CAN bus housing 1.1 serves as a mounting surface, on which two proportional flow valve mounting holes and one displacement sensor mounting hole are provided. The other end face is provided with a circuit board mounting cavity. The CAN bus end cover 1.2 is fixed to the CAN bus housing 1.1 by screws, and a special-shaped sealing ring 1.3 is used to seal the CAN bus end cover 1.2 and the CAN bus housing 1.1.

[0051] The LVDT displacement sensor 2 is a two-part split structure, as shown in FIG3 , and is divided into two parts: a displacement sensor body 2.1 and a displacement sensor transmitter circuit board 2.2.

[0052] The displacement sensor body 2.1 comprises a coil 2.11, a frame 2.12, a pressure-bearing tube 2.13, an elastic member 2.14, and an LVDT push rod 2.15. The frame 2.12 is hollow, with the elastic member 2.14 mounted at its top end. The LVDT push rod 2.15 is connected to the lower end of the elastic member 2.14. The pressure-bearing tube 2.13 is sleeved over the LVDT push rod 2.15 and mounted at the outlet of the frame 2.12. The coil 2.11 is wound around the outer ring of the frame 2.12 using a two-stage, three-wire winding method, reducing the axial dimension of the displacement sensor. The displacement sensor body 2.1 is mounted within the displacement sensor mounting hole of the CAN bus housing 1.1, with its axis aligned with the axis of the CAN bus housing 1.1. The LVDT push rod 2.15 extends outside the CAN bus housing 1.1. The rear end of the frame 2.12 is screwed to the CAN bus housing 1. The pressure-bearing tube 2.13 forms a seal with the CAN bus housing 1 via a sealing ring 2.16. The end of the LVDT push rod 2.15 maintains contact with the controlled valve core via an elastic member 2.14. The LVDT push rod 2.15 consists of a magnetically conductive section and a non-magnetically conductive section. One end of the non-magnetically conductive section abuts the end face of the controlled valve core, while the other end is connected to the magnetically conductive section. The LVDT push rod 2.15 follows the movement of the valve core, generating an induced electromotive force that is transmitted to the main control circuit board 4 via the displacement sensor transmitter circuit board 2.2, thereby achieving closed-loop control of the valve core displacement. After the coil of the displacement sensor body 2.1 is wound, it is wired and soldered to the displacement sensor transmitter circuit board 2.2.

[0053] The displacement sensor transmitter circuit board 2.2 is fastened to the circuit board device cavity of the CAN bus housing 1 by screws and connected to the main control circuit board 4 through connectors. The displacement sensor transmitter circuit board 2.2 converts the induced electromotive force of the displacement sensor body 2.1 into an electrical signal output that can be recognized by the main control circuit board 4.

[0054] There are two proportional flow valves 3, which are symmetrically installed on both sides of the LVDT displacement sensor 2 and placed in the proportional flow valve mounting hole of the CAN bus housing 1.1. The axis is parallel to the axis of the LVDT displacement sensor 2. The proportional flow valve 3 is connected to the main control circuit board 4 through pins.

[0055] The two proportional flow valves 3 have the same structure and are both two-position three-way flow valves. Taking one of them as an example, as shown in Figure 5, it includes a moving iron 3.1, a push rod 3.2 and a basin shoe valve sleeve 3.3. The axes of the moving iron 3.1, push rod 3.2 and basin shoe valve sleeve 3.3 are on the same straight line; one end of the push rod 3.2 contacts the moving iron 3.1, and the other end is inserted into the basin shoe valve sleeve 3.3, wherein the push rod 3.2 serves as both the output mechanism of the electromagnetic force and the valve core of the proportional flow valve, and the basin shoe valve sleeve 3.3 simultaneously assumes the role of the proportional electromagnetic basin shoe and the proportional flow valve sleeve. The structure of the integrated push rod valve core and the integrated basin shoe valve sleeve shortens the overall size of the proportional flow valve 3 and saves installation space. The contact end of the moving iron 3.1 and the push rod 3.2 is a bowl-shaped structure, the bottom of the bowl-shaped groove of the moving iron 3.1 is flat, and the bowl-shaped end face of the push rod 3.2 is flat. This structural form ensures the centering performance of the 3.1 moving iron and the 3.2 push rod during movement.

[0056] Proportional flow valve 3 has three oil ports: return port T, inlet port P, and working port A. When the solenoid coil is energized, inlet port P connects to working port A, allowing oil to flow into the pilot oil chamber. When the solenoid coil is de-energized, return port T connects to working port A, draining the pilot oil chamber. The two proportional flow valves 3 work together under control signals from the main control circuit board 4 to precisely control valve spool displacement.

[0057] The main control circuit board 4 is assembled in the circuit board device cavity of the CAN bus housing 1 by screws, and is perpendicular to the axis of the LVDT displacement sensor 2 and the two proportional flow valves 3; the main control circuit board 4 is connected to the LVDT displacement sensor 2 and the proportional flow valve 3, and the connection methods include but are not limited to soldering and connectors. As shown in FIG6 , the main control circuit board 4 includes a power module, an MCU control module, a driver module, a CAN communication module, an anti-interference module, an over-voltage and under-voltage protection module, etc. The power module provides adjustable voltage to other modules. The driver module outputs a PWM (pulse width modulation) signal to drive the proportional flow valve 3. The over-voltage and under-voltage protection module is connected to the output terminal of the power module to determine whether the output voltage of the power module is over-voltage or under-voltage. In the event of over-voltage or under-voltage, it disconnects the power module from other modules to improve the reliability of the circuit board. The anti-interference module is located between the over-voltage and under-voltage protection module and the driver module to filter out noise generated by external electromagnetic interference and improve the operating stability of the driver module. The CAN communication module realizes data exchange between the modules in the main control circuit board and information transmission between the main control circuit board and external connectors. The external connectors include LVDT displacement sensors, proportional flow valves, and connectors. The MCU control module can be programmed by the user. The main control circuit board 4 has fault diagnosis function and programmability. It can operate under wide voltage and temperature conditions, with high reliability and strong flexibility.

[0058] To power the CAN bus control unit and exchange external data, connector 5 is soldered to the main control circuit board 4. Its curved pin design facilitates connection to the controller. Specifically, connector adapter plate 6 is soldered to the pins of connector 5, reducing the number of internal interfaces within the CAN bus electronic control unit and avoiding wasted space on the main control circuit board 4. Connector 5 is fastened to the CAN bus housing 1 with screws, and a gasket seals the connector 5 and the CAN bus housing 1.

[0059] 7 and 8 , when the controlled valve core is subjected to closed-loop displacement control, the command signal is transmitted to the main control circuit board 4 via the upper computer or host controller via the connector 6. After being processed by the main control circuit board 4, it is converted into a PWM signal, which drives the push rod 3.8 of the proportional flow valve 3 to actuate. The oil inlet P of the proportional flow valve 3 is connected to the working oil port A, oil enters the pilot control chamber at one end of the controlled valve core, the valve core actuates, and the LVDT push rod 2.15 of the LVDT displacement sensor 2 moves with the controlled valve core, feeding back the valve core displacement to the main control circuit board 4. The main circuit board 4 subtracts the target displacement from the actual displacement of the valve core. The composite regulator selects the corresponding control logic based on the size of the displacement deviation, controls the two proportional flow valves 3 separately, and controls the valve core displacement in real time by independently adjusting the back pressure at both ends of the valve core, thereby improving the flexibility and energy saving of the valve core displacement control.

[0060] In this embodiment, the CAN bus housing consists of a CAN bus outer shell and a CAN bus end cap, which together form a space for accommodating the displacement sensor, proportional flow valve, and main control circuit board. The LVDT displacement sensor adopts a two-stage split design and is installed inside the CAN bus housing. Its push rod follows the movement of the controlled valve core and provides real-time feedback of the valve core displacement signal to the main control circuit board, achieving closed-loop displacement control. The proportional flow valve adopts a highly integrated design with an integrated valve core and push rod, and an integrated valve sleeve and valve shoe. It consists of two identical two-position, three-way proportional flow valves symmetrically located on either side of the LVDT displacement sensor. When the solenoid coil is energized, the proportional flow valve's oil inlet port P connects to the working oil port A, allowing oil to flow into the pilot chamber. When the solenoid coil is de-energized, the proportional flow valve's oil return port T connects to the working oil port A, draining oil from the pilot chamber. The main control circuit board includes a power module, an MCU control module, a driver module, a CAN communication module, an anti-interference module, an over- and under-voltage protection module, and other modules. Through a control program, it drives the proportional flow valve to control the pressure in the pilot chamber of the controlled valve core, dispatches feedback signals from the displacement sensor, and enables external data exchange. The CAN bus electronic control unit provided by the present invention adopts a composite pressure control method for the controlled valve core control chamber. The back pressure at both ends of the main valve core can be adjusted independently or logically controlled in pairs. Combined with the displacement deviation of the controlled valve core, the displacement of the controlled valve core is adjusted in real time to achieve high-precision control of the valve core displacement.

[0061] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A CAN bus electronic control unit, characterized in that: It comprises a CAN bus housing (1), an LVDT displacement sensor (2), a proportional flow valve (3) and a main control circuit board (4), The LVDT displacement sensor (2) is of a split structure, comprising a displacement sensor body (2.1) and a displacement sensor transmitter circuit board (2.2); the displacement sensor body (2.1) is connected to the displacement sensor transmitter circuit board (2.2) via a coil lead; There are two proportional flow valves (3), which are symmetrically installed on both sides of the displacement sensor body (2.1); The LVDT displacement sensor (2), the proportional flow valve (3) and the main control circuit board (4) are installed in a CAN bus housing (1); the displacement sensor transmitter circuit board (2.2) and the control end of the proportional flow valve (3) are respectively connected to the main control circuit board (4); the oil port end of the proportional flow valve (3) is connected to the controlled element; the detection end of the displacement sensor body (2.1) is connected to the valve core of the controlled element; the proportional flow valve (3) comprises a moving iron (3.1), a push rod (3.2) and a basin shoe valve sleeve (3.3); the moving iron (3.1), the push rod (3.2) and the basin shoe valve sleeve (3.3) are coaxially arranged; one end of the push rod (3.2) contacts the moving iron (3.1) and the other end is inserted into the basin shoe valve sleeve (3.3).

2. A CAN bus electronic control unit according to claim 1, characterized in that: The proportional flow valve (3) is a two-position three-way solenoid valve. When the electromagnetic coil of the proportional flow valve (3) is energized, the oil inlet port P is connected to the working oil port A; when the electromagnetic coil of the proportional flow valve (3) is de-energized, the oil return port T is connected to the working oil port A.

3. The CAN bus electronic control unit according to claim 1, characterized in that: The contact ends of the moving iron (3.1) and the push rod (3.2) are in a bowl-shaped structure.

4. The CAN bus electronic control unit according to claim 1, characterized in that: The CAN bus housing (1) comprises a CAN bus housing (1.1) and a CAN bus end cover (1.2); one end surface of the CAN bus housing (1.1) is a mounting surface, and a proportional flow valve mounting hole and a displacement sensor mounting hole are provided on the mounting surface; the other end surface of the CAN bus housing (1.1) is provided with a circuit board mounting cavity; and the CAN bus end cover (1.2) is fixedly connected to the CAN bus housing (1.1) by means of screws.

5. The CAN bus electronic control unit according to claim 4, characterized in that: A special-shaped sealing ring (1.3) is also provided between the CAN bus end cover (1.2) and the CAN bus housing (1.1).

6. The CAN bus electronic control unit according to claim 1, characterized in that: The displacement sensor body (2.1) comprises a coil (2.11), a frame (2.12), a pressure-bearing tube (2.13) and an LVDT push rod (2.15); the frame (2.12) is hollow and its tail is fixed to the CAN bus housing (1) by means of screws; an elastic member (2.14) is provided at the top of the frame (2.12); the lower end of the elastic member (2.14) is connected to the LVDT push rod (2.15); the pressure-bearing tube (2.13) is sleeved on the LVDT push rod (2.15); the coil (2.11) is wound on the outer ring of the frame (2.12) in a two-segment three-wire winding manner; and the displacement sensor body (2.1) is connected to the displacement sensor transmitter circuit board (2.2) via the lead wire of the coil (2.11).

7. The CAN bus electronic control unit according to claim 6, characterized in that: The LVDT push rod (2.15) comprises a magnetic conductive section and a non-magnetic conductive section. One end of the non-magnetic conductive section abuts against the end face of the valve core of the controlled element through an elastic member (2.14), and the other end is connected to the magnetic conductive section.

8. The CAN bus electronic control unit according to claim 6, characterized in that: A sealing ring (2.16) is provided between the pressure-bearing pipe (2.13) and the CAN bus housing (1).

9. The CAN bus electronic control unit according to claim 1, characterized in that: The main control circuit board (4) comprises a power supply module, an MCU control module, a drive module, a CAN communication module, an anti-interference module, and an over-voltage and under-voltage protection module; The power module provides adjustable voltage to other modules. The driving module outputs a PWM signal to drive the proportional flow valve to operate. The over-voltage and under-voltage protection module is connected to the output end of the power module to determine whether the output voltage of the power module is over-voltage or under-voltage, and disconnects the power module from other modules in the event of over-voltage or under-voltage, so as to improve the reliability of the circuit board. The anti-interference module is located between the over-voltage and under-voltage protection module and the driving module, and is used to filter out the clutter generated by the voltage due to external electromagnetic interference, thereby improving the operating stability of the driving module. The CAN communication module realizes data interaction between modules in the main control circuit board (4), and information transmission between the main control circuit board (4) and external connecting parts. The MCU control module controls the coordinated actions of other modules and performs software programming according to user requirements.

10. The CAN bus electronic control unit according to claim 1, characterized in that: It also includes a plug-in connector (5) and a plug-in connector adapter plate (6); The plug connector (5) is connected to the main control circuit board (4), and the plug connector adapter board (6) is connected to the plug pins of the plug connector (5).

11. A CAN bus electronic control method, characterized in that: The application of the CAN bus electronic control unit as claimed in claim 1 comprises the following steps: Controlling the action of the proportional solenoid valve (3) in the CAN bus electronic control unit; Obtain the valve core target displacement and actual displacement of the controlled element in the CAN bus electronic control unit; Calculate the deviation err between the target displacement and the actual displacement, and compare it with the preset deviation band Δerr; If err>Δerr, any one proportional flow valve (3) in the CAN bus electronic control unit is controlled to act alone, and then the deviation is adjusted by the single-acting deviation regulator Con1; otherwise, the two proportional flow valves (3) in the CAN bus electronic control unit are controlled to act together, and then the deviation is adjusted by the double-acting deviation regulator Con2.

Images