Electromagnetic valve driving circuit based on intelligent MOS and working method thereof

Abstract

The invention discloses an intelligent # imgabs0-based electromagnetic valve driving circuit and a working method thereof, and belongs to the field of automobile electronic control, the intelligent # imgabs0-based electromagnetic valve driving circuit comprises an MCU # imgabs2, a # imgabs3 driving module, an intelligent # imgabs4 and a controlled electromagnetic valve, the MCU # imgabs2 is used for outputting # imgabs1 square wave signals, the # imgabs5 is electrically connected with the intelligent # imgabs7 through a # imgabs6 driving module, the intelligent # imgabs8 is connected between one end of an electromagnetic coil of the controlled electromagnetic valve and a grounding end, and the other end of the electromagnetic coil of the controlled electromagnetic valve is electrically connected with the intelligent # imgabs4. And the other end of the electromagnetic coil is electrically connected with a 12V power supply end and is used for controlling the on-off of the intelligent # imgabs11 # through the # imgabs10 # driving module based on the # imgabs9 # output high-low level signal so as to control the on-off of the controlled electromagnetic valve. By the adoption of the electromagnetic valve driving circuit based on the intelligent # imgabs12 and the working method of the electromagnetic valve driving circuit, the # imgabs13 outputs # imgabs14 square waves to control on-off of the intelligent # imgabs15, then the controlled electromagnetic valve can be controlled to be opened and closed, meanwhile, low cost and high performance are both considered, and therefore the market requirement is met.

Description

Technical Field

[0001] The present invention relates to the field of automotive electronic control technology, and in particular to a method based on intelligent The invention discloses a solenoid valve driving circuit and a working method thereof. Background Art

[0002] With the continuous innovation and technological progress of the automotive industry, solenoid valves, as key components for achieving precise control, play an increasingly important role in various complex control systems of automobiles.

[0003] The mainstream implementation schemes of solenoid valve control systems on the current market mostly rely on high-performance imported application-specific integrated circuits. , in order to ensure the efficiency and accuracy of control. However, this commonly used solution has limitations in some specific application scenarios, especially those that only require precise control of a few solenoid valves. In these cases, a full-featured, high-performance Not only does it cause excess resources, such as idle computing power and additional functions, but it also brings cost diseconomies. Summary of the invention

[0004] The purpose of the present invention is to provide a The solenoid valve driving circuit and the working method thereof solve the above-mentioned technical problems.

[0005] To achieve the above object, the present invention provides a The solenoid valve driving circuit includes an MCU for outputting a PWM square wave signal, a MOS driving module, an intelligent MOS and a controlled solenoid valve, wherein the MCU is electrically connected to the intelligent MOS via the MOS driving module, the intelligent MOS is connected between one end of the electromagnetic coil of the controlled solenoid valve and a ground terminal, and the other end of the electromagnetic coil is electrically connected to a 12V power supply terminal, so as to realize the control of the on and off of the intelligent MOS via the MOS driving module based on the output high and low level signals of the MCU, so as to control the opening and closing of the controlled solenoid valve.

[0006] Preferably, the MOS driving module includes an interlocked conduction transistor group and an interlocked shutoff transistor group, the interlocked conduction transistor group includes a first conduction transistor and a second conduction transistor, the interlocked shutoff transistor group includes a first shutoff transistor and a second shutoff transistor, and the first conduction transistor, the second conduction transistor, the first shutoff transistor and the second shutoff transistor are all NPN transistors; The base of the first conducting transistor is connected to the PWM square wave signal output pin of the MCU, the emitter of the first conducting transistor is grounded, the collector of the first conducting transistor is connected to the base of the first shut-off transistor, the emitter of the first shut-off transistor is grounded, the collector of the first shut-off transistor is connected to the base of the second conducting transistor, the collector of the second conducting transistor is connected to the 5V power supply terminal, the emitter of the second conducting transistor is connected to the collector of the second shut-off transistor, the emitter of the second shut-off transistor is grounded, the base of the second shut-off transistor is connected to the base of the first shut-off transistor via a clamping diode, and the base of the first shut-off transistor and the collector of the first conducting transistor are both connected to the 5V power supply terminal; intelligent The gate of the second transistor is connected between the emitter of the second transistor and the collector of the second transistor. The drain of the electromagnetic coil is connected in series with the 12V power supply terminal. The source is grounded.

[0007] Preferably, the intelligent MOS includes a MOS tube, a gate control unit, an over-temperature protection unit, an over-voltage protection unit, an over-current protection unit and a temperature sensor for monitoring the temperature of the MOS tube, the input end of the gate control unit is connected to the MOS driving module, and the output end of the gate control unit is connected to the gate of the MOS tube; The gate control unit is also connected to the over-temperature protection unit and the over-current protection unit respectively. The over-voltage protection unit is connected between the gate and the drain of the MOS tube. The over-current protection unit is connected between the source of the MOS tube and the gate control unit.

[0008] Preferably, the overcurrent protection unit is a linear current limiter for reading the voltage difference between the source and the drain of the MOS tube to obtain the current of the MOS tube, and for adjusting the duty cycle of the driving waveform of the gate control unit according to the comparison result between the obtained MOS tube current and the typical value; The overvoltage protection unit is the parasitic diode of the MOS tube; The gate control unit is the interface of the MCU.

[0009] Preferably, Also respectively with The gate and drain of the tube are connected to collect The input frequency and output frequency of the tube are used to combine The output frequency can be used for fault diagnosis.

[0010] Preferably, the frequency range of the PWM square wave signal output by the MCU is 2KHz-16KHz.

[0011] The working method of the solenoid valve driving circuit based on the intelligent MOS includes cyclically alternating high-level driving on and low-level driving off; The high-level drive conduction step is as follows: the MCU outputs a high-level signal to the base of the first conduction transistor, the first conduction transistor is turned on, the collector of the first conduction transistor is grounded, the first turn-off transistor is driven to be turned off, and the second turn-off transistor is turned off through the clamping diode. At this time, the 5V power supply end loads voltage to the base of the second conduction transistor, the second conduction transistor is turned on, and then the voltage is loaded to The gate of the tube, The tube is connected, the electromagnetic coil is energized to form a path, and the controlled electromagnetic valve opens; The low-level driving shutdown steps are as follows: the MCU outputs a low-level signal to the base of the first conduction transistor, the first conduction transistor is turned off, the collector of the first conduction transistor stops being grounded, the 5V power supply end loads voltage to the base of the first turn-off transistor, the first turn-off transistor is turned on, and the second turn-off transistor is driven to turn on through the clamping diode. At this time, the base of the second conduction transistor is grounded through the first turn-off transistor, and the second conduction transistor is turned off. The gate of the tube is grounded through the second turn-off transistor. The tube is closed, the electromagnetic coil is de-energized, and the controlled solenoid valve is closed.

[0012] Preferably, during the operation of cyclically alternating high-level driving on and low-level driving off, fault diagnosis and fault action protection are performed based on the collected frequencies of the gate and drain of the MOS tube.

[0013] Preferably, the MCU collects the data by capturing the count on both edges. The drain and gate frequencies of the transistor are measured, and the MCU register is read to obtain the MCU output frequency. The following fault diagnosis and fault action protection are performed: When collected The gate frequency of the tube is the same as the output frequency of the MCU, and When the drain frequency and gate frequency of the tube are within the set error range, it is determined The tube is in normal working condition; When collected The gate frequency of the tube is the same as the output frequency of the MCU, and When the ratio of the drain frequency of the MOS tube to the gate frequency of the MOS tube is within the set range, it is determined The tube is in an overcurrent state. At this time, the MCU adjusts the high level time in the output waveform through the gate drive unit to The tube is limited to the typical value range; when When the voltage difference between the source and drain of the tube is greater than the set value, the register diode undergoes reverse avalanche breakdown, and the determination The tube is in overpressure state; When collected The gate frequency of the tube is the same as the output frequency of the MCU. When the drain of the tube does not detect the frequency, it is determined The tube is in an over-temperature state, and the over-temperature protection unit turns off the gate drive unit, making The tube is turned off, and the temperature sensor is used to collect The temperature of the tube is monitored and it is restarted when the acquisition temperature falls below the threshold. Tube.

[0014] Preferred, typical value The calculation formula is as follows: ; In the formula, express Tube drain voltage; express Output The duty cycle of the square wave; express The internal resistance of the tube.

[0015] Therefore, the present invention adopts the above-mentioned intelligent The solenoid valve driving circuit and the working method thereof have the following beneficial effects: 1. Pass Output Square wave control intelligence The on and off of the controlled solenoid valve can be controlled, and low cost and high performance are taken into account at the same time, thus meeting the needs of the market; 2. It has a fault diagnosis function, which can act quickly when overcurrent or overtemperature occurs to avoid further expansion of losses.

[0016] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a kind of intelligent The circuit schematic diagram of the solenoid valve drive circuit; Figure 2 The present invention is a kind of intelligent Intelligent solenoid valve drive circuit The structural diagram of Figure 3 The present invention is a kind of intelligent The structural block diagram of the solenoid valve drive circuit; Figure 4 The output waveform diagram of the embodiment of the present invention under normal working state; Figure 5 This is an output waveform diagram under an overcurrent state of an embodiment of the present invention; Figure 6 This is an output waveform diagram under an over-temperature state of an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0020] like Figure 1-Figure 3 As shown, a smart The solenoid valve driving circuit includes an MCU for outputting a PWM square wave signal, a MOS driving module, an intelligent MOSQ15 and a controlled solenoid valve, wherein the MCU is electrically connected to the intelligent MOSQ15 via the MOS driving module, the intelligent MOSQ15 is connected between one end of an electromagnetic coil LSD5 of the controlled solenoid valve and a ground terminal, and the other end of the electromagnetic coil LSD5 is electrically connected to a 12V power supply terminal COIL_SUP, so as to realize the output high and low level signals based on the MCU to control the on and off of the intelligent MOSQ15 via the MOS driving module, so as to control the opening and closing of the controlled solenoid valve.

[0021] Specifically, the MOS driving module includes an interlocked conduction transistor group and an interlocked shutoff transistor group, the interlocked conduction transistor group includes a first conduction transistor Q69B and a second conduction transistor Q69A, the interlocked shutoff transistor group includes a first shutoff transistor Q68B and a second shutoff transistor Q68A, the first conduction transistor Q69B, the second conduction transistor Q69A, the first shutoff transistor Q68B and the second shutoff transistor Q68A are all NPN transistors; the base of the first conduction transistor Q69B is connected to the PWM square wave signal output pin of the MCU, the emitter of the first conduction transistor Q69B is grounded, the collector of the first conduction transistor Q69B is connected to the base of the first shutoff transistor Q68B, the emitter of the first shutoff transistor Q68B is grounded, and the collector of the first shutoff transistor Q68B is connected to the second conduction transistor Q68B. The base of the second transistor Q69A is connected, the collector of the second transistor Q69A is connected to the 5V power supply terminal VCC5, the emitter of the second transistor Q69A is connected to the collector of the second transistor Q68A, the emitter of the second transistor Q68A is grounded, the base of the second transistor Q68A is connected to the base of the first transistor Q68B via a clamping diode, the base of the first transistor Q68B and the collector of the first transistor Q69B are both connected to the 5V power supply terminal VCC5; the gate of the smart MOS Q15 is connected between the emitter of the second transistor Q69A and the collector of the second transistor Q68A, the drain of the smart MOS Q15 is connected in series with the electromagnetic coil LSD5 and then electrically connected to the 12V power supply terminal COIL_SUP, and the source of the smart MOS Q15 is grounded.

[0022] The intelligent MOSQ15 includes a MOS tube, a gate control unit, an over-temperature protection unit, an over-voltage protection unit, an over-current protection unit and a temperature sensor for monitoring the temperature of the MOS tube. The input end of the gate control unit is connected to the MOS driving module, and the output end of the gate control unit is connected to the gate of the MOS tube; the gate control unit is also connected to the over-temperature protection unit and the over-current protection unit respectively, the over-voltage protection unit is connected between the gate and the drain of the MOS tube, and the over-current protection unit is connected between the source of the MOS tube and the gate control unit.

[0023] The overcurrent protection unit is a linear current limiter used to read the voltage difference between the source and drain of the MOS tube to obtain the current of the MOS tube, and is used to adjust the driving waveform duty cycle of the gate control unit according to the comparison result between the obtained MOS tube current and the typical value; the overvoltage protection unit is the parasitic diode of the MOS tube; the gate control unit is the interface of the MCU.

[0024] Also respectively with The gate and drain of the tube are connected to collect The input frequency and output frequency of the tube are used to combine The output frequency can be used for fault diagnosis.

[0025] The frequency range of the PWM square wave signal output by the MCU is 2KHz-16KHz.

[0026] The intelligent The working method of the solenoid valve driving circuit includes cyclically alternating high-level driving on and low-level driving off; The high-level driving conduction step is as follows: the MCU outputs a high-level signal to the base of the first conduction transistor Q69B, the first conduction transistor Q69B is turned on, the collector of the first conduction transistor Q69B is grounded, the first turn-off transistor Q68B is driven to turn off, and the second turn-off transistor Q68A is turned off through the clamping diode. At this time, the 5V power supply terminal VCC5 loads voltage to the base of the second conduction transistor Q69A, the second conduction transistor Q69A is turned on, and the voltage is then loaded to The gate of the tube, Tube conduction, electromagnetic coil The circuit is formed by electricity, and the controlled solenoid valve opens; The low-level driving shutdown steps are as follows: the MCU outputs a low-level signal to the base of the first conduction transistor Q69B, the first conduction transistor Q69B is turned off, the collector of the first conduction transistor Q69B stops being grounded, the 5V power supply terminal VCC5 loads voltage to the base of the first turn-off transistor Q68B, the first turn-off transistor Q68B is turned on, and the second turn-off transistor Q68A is driven to be turned on through the clamping diode. At this time, the base of the second conduction transistor Q69A is grounded through the first turn-off transistor Q68B, and the second conduction transistor Q69A is turned off. The gate of the tube is connected to the second turn-off transistor Ground, Tube shut-off, solenoid coil When the power is off, the controlled solenoid valve is closed.

[0027] like Figure 4-Figure 6 As shown in the figure, in the process of alternating high-level drive on and low-level drive off, when When the tube is turned on, The drain and source of the tube are turned on, the drain voltage is 0, when When the tube is turned off, The drain and source of the tube are not conducting, and the drain voltage is infinitely close to Output voltage, so it can be based on the collected The frequency of the gate and drain of the tube is used for fault diagnosis and fault action protection.

[0028] Specifically, the MCU collects data by capturing the count on both edges. The drain and gate frequencies of the transistor are measured, and the MCU register is read to obtain the MCU output frequency. The following fault diagnosis and fault action protection are performed: When collected The gate frequency of the tube is the same as the output frequency of the MCU, and When the drain frequency and gate frequency of the tube are within the set error range (3%), it is determined The tube is in normal working condition; When collected The gate frequency of the tube is the same as the output frequency of the MCU, and The drain frequency is When the proportion of the tube grid frequency is within the set range (1 / 5), it is judged The tube is in an overcurrent state. At this time, the MCU adjusts the high level time in the output waveform through the gate drive unit to The tube is limited to the typical value range; Typical Value The calculation formula is as follows: ; In the formula, express Tube drain voltage; express The duty cycle of the output PWM square wave; express The internal resistance of the tube.

[0029] Typical values ​​in this example =3.3A.

[0030] Reading with a linear current limiter The voltage difference between the source and drain of the tube is When the voltage difference between the source and drain of the tube is greater than the set value (40V), the parasitic diode undergoes reverse avalanche breakdown, and the determination The tube is in overpressure state; Continuous operation of overcurrent or overvoltage will cause The tube temperature rises, triggering the over-temperature protection (in this embodiment, When the tube reaches 170℃, the over-temperature protection is triggered). The gate frequency of the tube is the same as the output frequency of the MCU. When the drain of the tube does not detect the frequency, it is determined The tube is in an over-temperature state, and the over-temperature protection unit turns off the gate drive unit, making The tube is turned off, and the temperature sensor is used to collect The temperature of the tube is monitored and the system is restarted when the acquisition temperature drops below the threshold (155°C). Tube.

[0031] At the same time, the control frequency can support up to 50kHZ, which is also applicable to some applications in automotive electronics that have strict requirements on noise.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. An intelligent The solenoid valve driving circuit is characterized by: It includes an MCU for outputting PWM square wave signals, a MOS driving module, an intelligent MOS and a controlled solenoid valve. The MCU is electrically connected to the intelligent MOS via the MOS driving module. The intelligent MOS is connected between one end of the electromagnetic coil of the controlled solenoid valve and the ground terminal. The other end of the electromagnetic coil is electrically connected to the 12V power supply terminal. It is used to control the on and off of the intelligent MOS through the MOS driving module based on the output high and low level signals of the MCU to control the opening and closing of the controlled solenoid valve.

2. The solenoid valve driving circuit based on intelligent MOS according to claim 1, characterized in that: The driving module includes an interlocked conduction transistor group and an interlocked shutoff transistor group, the interlocked conduction transistor group includes a first conduction transistor and a second conduction transistor, the interlocked shutoff transistor group includes a first shutoff transistor and a second shutoff transistor, the first conduction transistor, the second conduction transistor, the first shutoff transistor and the second shutoff transistor are all NPN transistors; The base of the first conducting transistor is connected to the PWM square wave signal output pin of the MCU, the emitter of the first conducting transistor is grounded, the collector of the first conducting transistor is connected to the base of the first shut-off transistor, the emitter of the first shut-off transistor is grounded, the collector of the first shut-off transistor is connected to the base of the second conducting transistor, the collector of the second conducting transistor is connected to the 5V power supply terminal, the emitter of the second conducting transistor is connected to the collector of the second shut-off transistor, the emitter of the second shut-off transistor is grounded, the base of the second shut-off transistor is connected to the base of the first shut-off transistor via a clamping diode, and the base of the first shut-off transistor and the collector of the first conducting transistor are both connected to the 5V power supply terminal; intelligent The gate of the second transistor is connected between the emitter of the second transistor and the collector of the second transistor. The drain of the electromagnetic coil is connected in series with the 12V power supply terminal. The source is grounded.

3. According to claim 2, a method based on intelligence The solenoid valve driving circuit is characterized by: The intelligent MOS includes a MOS tube, a gate control unit, an over-temperature protection unit, an over-voltage protection unit, an over-current protection unit and a temperature sensor for monitoring the temperature of the MOS tube. The input end of the gate control unit is connected to the MOS driving module, and the output end of the gate control unit is connected to the gate of the MOS tube. The gate control unit is also connected to the over-temperature protection unit and the over-current protection unit respectively. The over-voltage protection unit is connected between the gate and the drain of the MOS tube. The over-current protection unit is connected between the source of the MOS tube and the gate control unit.

4. According to claim 3, a method based on intelligence The solenoid valve driving circuit is characterized by: The overcurrent protection unit is a linear current limiter for reading the voltage difference between the source and drain of the MOS tube to obtain the current of the MOS tube, and is used to adjust the driving waveform duty cycle of the gate control unit according to the comparison result between the obtained MOS tube current and the typical value; The overvoltage protection unit is the parasitic diode of the MOS tube; The gate control unit is the interface of the MCU.

5. According to claim 4, a method based on intelligence The solenoid valve driving circuit is characterized by: Also respectively with The gate and drain of the tube are connected to collect The input frequency and output frequency of the tube are used to combine The output frequency can be used for fault diagnosis.

6. According to claim 1, a method based on intelligence The solenoid valve driving circuit is characterized by: The frequency range of the PWM square wave signal output by the MCU is 2KHz-16KHz.

7. A method based on intelligence as claimed in claim 5. The working method of the solenoid valve driving circuit is characterized in that: It includes cyclically alternating high-level driving on and low-level driving off; The high-level drive conduction step is as follows: the MCU outputs a high-level signal to the base of the first conduction transistor, the first conduction transistor is turned on, the collector of the first conduction transistor is grounded, the first turn-off transistor is driven to turn off, and the second turn-off transistor is turned off through the clamping diode. At this time, the 5V power supply end loads voltage to the base of the second conduction transistor, the second conduction transistor is turned on, and then the voltage is loaded to The gate of the tube, The tube is connected, the electromagnetic coil is energized to form a path, and the controlled electromagnetic valve opens; The low-level driving shutdown steps are as follows: the MCU outputs a low-level signal to the base of the first conduction transistor, the first conduction transistor is turned off, the collector of the first conduction transistor stops being grounded, the 5V power supply end loads voltage to the base of the first turn-off transistor, the first turn-off transistor is turned on, and the second turn-off transistor is driven to turn on through the clamping diode. At this time, the base of the second conduction transistor is grounded through the first turn-off transistor, and the second conduction transistor is turned off. The gate of the tube is grounded through the second turn-off transistor. The tube is closed, the electromagnetic coil is de-energized, and the controlled solenoid valve is closed.

8. The method according to claim 7 based on intelligence The working method of the solenoid valve driving circuit is characterized in that: In the process of alternating high-level drive on and low-level drive off, based on the collected The frequency of the gate and drain of the tube is used for fault diagnosis and fault action protection.

9. The method according to claim 8 based on intelligence The working method of the solenoid valve driving circuit is characterized in that: MCU collects data by capturing counts on both edges The drain and gate frequencies of the transistor are measured, and the MCU register is read to obtain the MCU output frequency. The following fault diagnosis and fault action protection are performed: When collected The gate frequency of the tube is the same as the output frequency of the MCU, and When the drain frequency and gate frequency of the tube are within the set error range, it is determined The tube is in normal working condition; When collected The gate frequency of the tube is the same as the output frequency of the MCU, and When the ratio of the drain frequency of the MOS tube to the gate frequency of the MOS tube is within the set range, it is determined The tube is in an overcurrent state. At this time, the MCU adjusts the high level time in the output waveform through the gate drive unit to The tube is limited to the typical value range; when When the voltage difference between the source and drain of the tube is greater than the set value, the register diode undergoes reverse avalanche breakdown, and the determination The tube is in overpressure state; When collected The gate frequency of the tube is the same as the output frequency of the MCU. When the drain of the tube does not detect the frequency, it is determined The tube is in an over-temperature state, and the over-temperature protection unit turns off the gate drive unit, making The tube is turned off, and the temperature sensor is used to collect The temperature of the tube is monitored and it is restarted when the acquisition temperature falls below the threshold. Tube.

10. The working method of the solenoid valve driving circuit based on intelligent MOS according to claim 9, characterized in that: Typical Value The calculation formula is as follows: ； In the formula, express Tube drain voltage; Indicates the duty cycle of the PWM square wave output by the MCU; express The internal resistance of the tube.

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