Intelligent stepless speed regulation control and fault detection circuit for fan

Abstract

The utility model relates to the technical field of speed regulation control circuits, and provides an intelligent stepless speed regulation control and fault detection circuit for a fan, which comprises a power supply, a speed regulation controller, a fault detection component, a temperature detection component, an MCU (Microprogrammed Control Unit) controller and the fan, and is characterized in that the speed regulation controller comprises an amplifying circuit, a driving chip and a speed regulation control circuit; the speed regulation control circuit comprises a fan coil, the fan coil is connected with a power supply, the fan coil is connected with an inductor, the inductor is connected with a diode, one end of the diode is connected with the power supply, and one end of the fan coil is connected with a first capacitor. According to the utility model, through the on state of the power tube, the inductor carries out follow current discharge through the diode, and when the PWM frequency changes, the inductive reactance of the inductor also changes, so that different voltage values can be obtained on the fan coil, and the stepless adjustable change of the voltage of the fan coil is realized; and the functions of fan stop, full-speed rotation, stepless speed regulation of the rotating speed and the like are realized.

Description

Technical Field

[0001] The utility model relates to the technical field of speed control circuits, in particular to an intelligent stepless speed control and fault detection circuit for a fan. Background Art

[0002] Fans are mainly used in situations where heat dissipation is required. The existing technology mainly uses a fan that is powered on and always on. It is a fixed-speed fan and can only adjust the air volume by adjusting the damper opening. A large amount of energy is consumed on valves and baffles, so the efficiency is low. Direct and fast operation causes noise all the time and reduces the service life of the fan.

[0003] When heat dissipation is required, the fan speed is adjusted by changing the fixed voltage. This form of fan speed regulation has limited gears, and the noise of the fan speed change can be clearly heard. In addition, it is troublesome to adjust the circuit control and the loop loss increases. Once the fan fails, similar control methods cannot be detected. Not only does it not have a heat dissipation effect, but the product is prone to thermal protection, affecting the reliability of the equipment. Utility Model Content

[0004] The utility model aims to solve the shortcomings in the prior art and proposes an intelligent stepless speed control and fault detection circuit for a fan.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: an intelligent stepless speed control and fault detection circuit for a fan, comprising a power supply, a speed controller, a fault detection component, a temperature detection component, an MCU controller, and a fan. The speed controller comprises an amplifier circuit, a drive chip, and a speed control circuit. The speed control circuit comprises a fan coil, the fan coil is connected to the power supply, the fan coil is connected to an inductor, the inductor is connected to a diode, one end of the diode is connected to the power supply, one end of the fan coil is connected to a capacitor 1, the capacitor 1 is connected to the S pole of a power tube 1, the D pole of the power tube 1 is connected to one end of the diode, and the S pole of the power tube 1 is connected to grounding.

[0006] As a further description of the above technical solution:

[0007] The amplifier circuit includes power tube 2, the G pole of power tube 2 is connected to resistor 1, one end of resistor 1 is connected to the S pole of power tube 2, resistor 1 is grounded, both ends of resistor 1 are connected in parallel with capacitor 2, one end of capacitor 2 is connected to resistor 2, and resistor 2 is connected to the MCU controller.

[0008] As a further description of the above technical solution:

[0009] The temperature detection component is connected to the MCU controller.

[0010] As a further description of the above technical solution:

[0011] The NC, CA and NC ports of the driving chip are connected to the D pole of the power tube 2, and the AN port of the driving chip is connected to the resistor 5, and the resistor 5 is connected to the power supply.

[0012] As a further description of the above technical solution:

[0013] The G pole of the power tube 1 is connected to a resistor 3, one end of the resistor 3 is grounded, one end of the resistor 3 is connected to the VEE port of the driver chip, the resistor 3 is connected to a resistor 4, and the resistor 4 is connected to the VOUT port of the driver chip.

[0014] As a further description of the above technical solution:

[0015] The voltage of the power supply is a diode V, a ground V or an operational amplifier V.

[0016] As a further description of the above technical solution:

[0017] The fault detection component comprises a detection chip and an operational amplifier, and the output end of the operational amplifier is connected to the MCU controller.

[0018] The utility model has the following beneficial effects:

[0019] 1. In the utility model, through the opening state of the power tube, the inductor performs freewheeling discharge through the diode. When the PWM frequency changes, the inductive reactance on the inductor also changes, so that different voltage values ​​can be obtained on the fan coil, thereby realizing the stepless adjustable change of the fan coil voltage, realizing the functions of fan stop, full speed rotation, stepless speed regulation, etc., realizing stepless speed regulation of the fan, and optimizing the fan output noise.

[0020] 2. In the utility model, the detected temperature is sent to the MCU controller through the temperature detection component, and then the MCU controller will send out PWM waves with different duty cycles according to the size of the current temperature value read. The PWM wave is amplified by the amplifier circuit and then sent to the driver chip to control the power tube 2 to be turned on or off accordingly, and the fan is infinitely regulated in conjunction with the inductor, diode and capacitor 1 to realize intelligent control of the fan, which can significantly improve the service life of the fan and reduce the loss of the fan power supply circuit.

[0021] 3. In the utility model, when a fan fault is detected by the fault detection component, an alarm signal is issued in advance, and the user can respond in advance. The fan fault mode mainly detects the current of the fan coil when the fan is working. When the fan does not rotate abnormally, the fan current is zero. The MCU controller determines whether the fan is faulty by detecting the working current of the fan, and finally protects the equipment. The user can detect the fan fault in time to ensure the reliable operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of a fan intelligent stepless speed control and fault detection circuit proposed by the utility model;

[0023] Figure 2 This is a principle block diagram of a fan intelligent stepless speed control and fault detection circuit proposed by the utility model;

[0024] Figure 3 Partial principle of a fan intelligent stepless speed control and fault detection circuit proposed by the utility model Figure 1 ;

[0025] Figure 4 Partial principle of a fan intelligent stepless speed control and fault detection circuit proposed by the utility model Figure 2 .

[0026] Legend:

[0027] 1. Power supply; 2. Speed ​​controller; 3. Fault detection component; 4. Temperature detection component; 5. MCU controller; 6. Fan; 7. Amplifier circuit; 8. Driver chip; 9. Speed ​​control circuit; 10. Fan coil; 11. Inductor; 12. Diode; 13. Capacitor 1; 14. Power tube 1; 15. Grounding; 16. Power tube 2; 17. Resistor 1; 18. Capacitor 2; 19. Resistor 2; 20. Resistor 3; 21. Resistor 4; 22. Resistor 5; 23. Detection chip; 24. Operational amplifier. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in 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.

[0029] Reference Figure 1-Figure 4The utility model provides an embodiment: an intelligent stepless speed control and fault detection circuit for a fan 6, comprising a power supply 1, a speed controller 2, a fault detection component 3, a temperature detection component 4, an MCU controller 5, and a fan 6. The speed controller 2 comprises an amplifier circuit 7, a drive chip 8, and a speed control circuit 9. The speed control circuit 9 comprises a fan 6 coil, the fan 6 coil is connected to the power supply 1, the fan 6 coil is connected to an inductor 11, the inductor 11 is connected to a diode 12, one end of the diode 12 is connected to the power supply 1, and the fan 6 coil One end of is connected to capacitor 13, capacitor 13 is connected to the S pole of power tube 14, the D pole of power tube 14 is connected to one end of diode 12, the S pole of power tube 14 is connected to ground 15, through the opening state of the power tube, the inductor 11 performs freewheeling discharge through the diode 12, when the PWM frequency changes, the inductive reactance on the inductor 11 also changes, so that different voltage values ​​can be obtained on the coil of fan 6, thereby realizing the stepless adjustable change of the coil voltage of fan 6, and realizing the functions of fan 6 stopping, full speed rotation, stepless speed regulation, etc.

[0030] The amplifier circuit 7 includes a power tube 2 16, the G pole of the power tube 2 16 is connected to a resistor 17, one end of the resistor 17 is connected to the S pole of the power tube 2 16, the resistor 17 is connected to the ground 15, the two ends of the resistor 17 are connected in parallel with a capacitor 2 18, one end of the capacitor 2 18 is connected to a resistor 2 19, the resistor 2 19 is connected to the MCU controller 5, the temperature detection component 4 is connected to the MCU controller 5, the NC, CA, and NC ports of the drive chip 8 are connected to the D pole of the power tube 2 16, the AN port of the drive chip 8 is connected to a resistor 5 22, the resistor 5 22 is connected to the power supply 1, the G pole of the power tube 14 is connected to a resistor 3 20, one end of the resistor 3 20 is connected to the ground 15, one end of the resistor 3 20 is connected to the VEE port of the drive chip 8, the resistor 3 20 is connected to a resistor 4 21, the resistor 4 21 is connected to the VOUT port of the drive chip 8, the voltage of the power supply 1 is a diode 12V, a ground 15V or an operational amplifier 24V, the fault detection component 3 includes a detection chip 23 and an operational amplifier 24. The output end of the operational amplifier 24 is connected to the MCU controller 5. The detected temperature is sent to the MCU controller 5 through the temperature detection component 4. Then the MCU controller 5 will send out PWM waves with different duty cycles according to the size of the current temperature value read. The PWM wave is amplified by the amplifier circuit 7 and then sent to the driver chip 8 to control the power tube 2 16 to be turned on or off accordingly, and cooperate with the inductor 11, the diode 12, and the capacitor 13 to perform stepless speed regulation of the fan 6. When the fault detection component 3 detects that the fan 6 fails, an alarm signal is issued in advance, and the user can respond in advance. The fault mode of the fan 6 mainly detects the current of the fan 6 coil when the fan 6 is working. When the fan 6 does not rotate abnormally, the current of the fan 6 is zero. The MCU controller 5 determines whether the fan 6 is faulty by detecting the working current of the fan 6, and finally protects the equipment.

[0031] Working principle: When the device is powered on, the 18B20 temperature detection component 4 sends the detected temperature to the MCU controller 5, and then the MCU controller 5 will send out PWM waves with different duty cycles according to the current temperature value read. The amplifier circuit 7 amplifies the PWM wave signal and then sends it to the driver chip 8 to control the power tube 16 to turn on or off accordingly, and cooperate with the inductor 11, the diode 12, and the capacitor 13 to perform stepless speed regulation of the fan 6, that is, the PWM duty cycle will be adjusted from zero to one hundred according to the temperature value of the environment or the device. When the duty cycle is zero, the fan 6 does not rotate, and when the duty cycle is one hundred, the fan 6 rotates at full speed. This process realizes stepless speed regulation. The specific working mode is: when the 18B20 temperature detection component When the temperature of the environment or equipment is less than a certain temperature value, the fan 6 will not rotate (it does not need to rotate in the normal temperature environment, and it is set to be less than 45℃ and the fan 6 will not rotate). When it is detected that the temperature of the environment or equipment is greater than 45℃, the fan 6 will be turned on, and the environment or equipment will start to dissipate heat. As the temperature rises, the speed of the fan 6 increases (45℃ to 65℃ for stepless speed regulation, 65℃ for full speed rotation of the fan 6, the temperature adjustment range can be adjusted arbitrarily according to the actual situation), that is, when the temperature of the environment or equipment is less than 45℃, the PWM duty cycle is zero, and the fan 6 will not rotate. When the temperature of the environment or equipment is less than 65℃, the PWM duty cycle is one hundred, and the fan 6 runs at full speed; Fault detection mode: When the fault detection component 3 detects a fault in the fan 6 (the fault includes: The fan is blocked, the fan does not rotate abnormally), and an alarm signal is issued in advance, so that the user can respond in advance. The fault mode of fan 6 mainly detects the current of the fan coil 10 when the fan is working. When the fan 6 is blocked, the current of the fan coil 10 is 1.2-1.5 times the current of the fan 6 at full speed (obtained according to the fan parameters). When the fan does not rotate abnormally, the current of the fan 6 is zero. The MCU controller determines whether the fan 6 is faulty by detecting the working current of the fan 6, and finally protects the equipment; Stepless speed regulation principle: when the power tube 14 is on, the voltage of the inductor 11 is positive on the left and negative on the right, and the power supply charges the capacitor 13 and the inductor 11 through the fan. At this time, it can be understood that the fan coil 10 and the inductor 11 are divided. When the power tube 1 4 is in the off state, the voltage of the inductor 11 is negative on the left and positive on the right. At this time, the inductor 11 performs freewheeling discharge through the diode 12. As the PWM frequency changes, the inductive reactance on the inductor 11 also changes, so that different voltage values ​​can be obtained on the fan coil 10. When the PWM duty cycle is zero, the power tube 14 is fully closed, and the fan coil 10 has no power supply circuit, so the fan 6 does not rotate at this time. When the PWM duty cycle is one hundred, the power tube 14 is fully open, the inductor 11 is regarded as a short-circuited wire, and the power supply 1+24V is all added to the fan coil 10, so the fan 6 rotates at full speed at this time. The circuit realizes the stepless adjustable change of the voltage of the fan coil 10 through this mode, and realizes the functions of stopping the fan 6, rotating at full speed, and stepless speed regulation.

[0032] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An intelligent stepless speed control and fault detection circuit for a fan, comprising a power supply (1), a speed controller (2), a fault detection component (3), a temperature detection component (4), an MCU controller (5), and a fan (6), characterized in that: The speed control controller (2) comprises an amplifier circuit (7), a drive chip (8), and a speed control circuit (9); the speed control circuit (9) comprises a fan coil (10); the fan coil (10) is connected to a power supply (1); the fan coil (10) is connected to an inductor (11); the inductor (11) is connected to a diode (12); one end of the diode (12) is connected to the power supply (1); one end of the fan coil (10) is connected to a capacitor (13); the capacitor (13) is connected to the S pole of a power tube (14); the D pole of the power tube (14) is connected to one end of the diode (12); and the S pole of the power tube (14) is connected to a ground (15).

2. According to claim 1, a fan intelligent stepless speed control and fault detection circuit is characterized in that: The amplifier circuit (7) comprises a power tube 2 (16), the G pole of the power tube 2 (16) is connected to a resistor 1 (17), one end of the resistor 1 (17) is connected to the S pole of the power tube 2 (16), the resistor 1 (17) is connected to the ground (15), the two ends of the resistor 1 (17) are connected in parallel to a capacitor 2 (18), one end of the capacitor 2 (18) is connected to a resistor 2 (19), and the resistor 2 (19) is connected to the MCU controller (5).

3. The intelligent stepless speed control and fault detection circuit for a fan according to claim 1 is characterized in that: The temperature detection component (4) is connected to the MCU controller (5).

4. The intelligent stepless speed control and fault detection circuit for a fan according to claim 1 is characterized in that: The NC, CA, and NC ports of the driving chip (8) are connected to the D pole of the power tube 2 (16), the AN port of the driving chip (8) is connected to a resistor 5 (22), and the resistor 5 (22) is connected to a power supply (1).

5. The intelligent stepless speed control and fault detection circuit for a fan according to claim 1 is characterized in that: The G pole of the power tube 1 (14) is connected to a resistor 3 (20), one end of the resistor 3 (20) is connected to the ground (15), one end of the resistor 3 (20) is connected to the VEE port of the driver chip (8), the resistor 3 (20) is connected to a resistor 4 (21), and the resistor 4 (21) is connected to the VOUT port of the driver chip (8).

6. The intelligent stepless speed control and fault detection circuit for a fan according to claim 1 is characterized in that: The voltage of the power supply (1) is 12V, 15V or 24V.

7. The intelligent stepless speed control and fault detection circuit for a fan according to claim 1 is characterized in that: The fault detection component (3) comprises a detection chip (23) and an operational amplifier (24), and the output end of the operational amplifier (24) is connected to the MCU controller (5).

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