A fan compatible system and working method thereof

Abstract

The present application discloses a fan compatible system and a working method thereof, wherein the system comprises a sub-main control module, a compatible module and an interface module; the main control module is suitable for outputting the control signal of the fan; the interface module is suitable for connecting to the terminals of a four-wire fan or a five-wire fan respectively through different numbers and / or different types of interfaces; the MCU side of the compatible module is communicatively connected with the main control module, and the interface side of the compatible module is communicatively connected with the interface module; the compatible module is suitable for transferring the control signal of the main control module to the corresponding interface of the interface module according to the type of fan connected to the interface module. The beneficial effects of the present application: compared with the traditional fan interface, the present application can be compatible with both four-wire fans and five-wire fans by setting the compatible module and the interface module. There is no need to design different hardware circuits and control methods for different fans, which can effectively save the design cost and maintenance cost of the system.

Description

Technical Field

[0001] The present application relates to the technical field of heat dissipation of power equipment, and in particular to a fan compatible system and a working method thereof. Background Art

[0002] In the power conversion system, fans are usually used to dissipate heat from the power converter. In order to prevent dust or foreign matter from entering the heat dissipation duct of the power converter and affecting the heat dissipation system of the power converter, the fan needs to have a reverse dust removal function. The existing fans with reverse function include four-wire custom fans and five-wire fans.

[0003] The five-wire fan includes a signal line for controlling forward rotation, a signal line for controlling reverse rotation, a positive power line, a negative power line, and a speed feedback signal (FG) line. The fan receives a forward rotation signal or a reverse rotation signal to control the fan to rotate forward or reverse. Compared with the five-wire system, the four-wire fan does not have a reverse rotation signal line. It realizes forward and reverse rotation control by customizing different wave generation methods, such as changing the PWM frequency, changing the PWM duty cycle, and changing the PWM frequency and duty cycle at the same time.

[0004] When selecting cooling fans for traditional power equipment, they must be matched with interfaces, making it difficult for existing four-wire fans and five-wire fans to be compatible in terms of hardware interfaces and controls. Therefore, in actual applications, hardware and controls need to be designed separately for different fans, which increases the design and maintenance costs of the system and also brings inconvenience to subsequent fan replacement. Summary of the invention

[0005] One of the objectives of the present application is to provide a fan compatible system that can solve at least one of the defects in the above-mentioned background technology.

[0006] Another object of the present application is to provide a working method of a fan-compatible system that can solve at least one defect in the above-mentioned background technology.

[0007] In order to achieve at least one of the above-mentioned purposes, the technical solution adopted in the present application is: a fan compatible system, including a main control module, a compatible module and an interface module; the main control module is suitable for outputting a control signal of the fan; the interface module is suitable for connecting to the terminals of a four-wire fan or a five-wire fan through different numbers and / or different types of interfaces; the MCU side of the compatible module is communicatively connected to the main control module, and the interface side of the compatible module is communicatively connected to the interface module; the compatible module is suitable for forwarding the control signal output by the main control module to the corresponding interface of the interface module according to the type of fan connected to the interface module.

[0008] Preferably, the interface module includes a four-wire interface and a five-wire interface, the four-wire interface is used to connect a four-wire fan, and the five-wire interface is used to connect a five-wire fan; the interface side of the compatible module includes a PWM+ interface and a PWM- interface; the four-wire interface is connected to the PWM+ interface of the compatible module, and the five-wire interface is connected to the PWM+ interface and the PWM- interface of the compatible module.

[0009] Preferably, the four-wire interface and the five-wire interface are respectively arranged at independent physical interfaces, so that the four-wire fan and the five-wire fan are connected to the corresponding physical interfaces through terminals; or, the four-wire interface and the five-wire interface are arranged at the same physical interface, and the four-wire fan and the five-wire fan are both connected to the same physical interface using five-wire terminals.

[0010] Preferably, the compatible module includes a logic judgment circuit and a forward and reverse selection circuit; the logic judgment circuit is suitable for receiving the control signal output by the main control module to judge the direction in which the fan needs to rotate, and outputs different level signals based on the different directions in which the fan needs to rotate; the forward and reverse selection circuit is suitable for receiving the level signal output by the logic judgment circuit and the control signal output by the main control module, and forwarding the control signal to the PWM+ interface or the PWM- interface based on the received signal; wherein, when the interface module is connected to a four-wire fan, the forward and reverse selection circuit is suitable for forwarding the control signal to the PWM+ interface; when the interface module is connected to a five-wire fan, the forward and reverse selection circuit is suitable for forwarding the control signal to one of the PWM+ interface and the PWM- interface, and forwarding a low level signal to the other interface.

[0011] Preferably, the control signal output by the main control module includes a PWM signal and a VCC_ctl signal; the logic judgment circuit includes a gate circuit and a trigger; the input end of the gate circuit is suitable for receiving the PWM signal and the VCC_ctl signal; the input end of the trigger is connected to the output end of the gate circuit, and the output end of the trigger is connected to the input end of the forward and reverse selection circuit; for a five-wire fan, if the fan is switched to forward rotation, the VCC_ctl signal and the PWM signal are both low level, and then the trigger will output a low level; if the fan is switched to reverse rotation, the VCC_ctl signal is low level, the PWM signal is high level, and then the trigger will output a high level; for a four-wire fan, if the fan is switched to reverse rotation, the VCC_ctl signal and the PWM signal are both low level, and then the trigger will output a low level.

[0012] Preferably, the forward and reverse selection circuit includes a third NOT gate, a third AND gate and a fourth AND gate; the input end of the third NOT gate is suitable for receiving the output signal of the logic judgment circuit, the input end of the third AND gate is suitable for receiving the output signal of the third NOT gate and the PWM signal respectively, and the output end of the third AND gate is connected to the PWM+ interface; the input end of the fourth AND gate is suitable for receiving the output signal of the logic judgment circuit and the PWM signal respectively, and the output end of the fourth AND gate is connected to the PWM-interface; for a five-wire fan, if the fan needs to be switched to forward rotation, the third AND gate is suitable for outputting a PWM signal to the PWM+ interface, and the fourth AND gate is suitable for outputting a low level to the PWM-interface; if the fan needs to be switched to reverse rotation, the third AND gate is suitable for outputting a low level to the PWM+ interface, and the fourth AND gate is suitable for outputting a PWM signal to the PWM-interface; for a four-wire fan, the third AND gate is suitable for constantly outputting a PWM signal to the PWM+ interface, and the fourth AND gate is suitable for outputting a constant low level to the PWM-interface.

[0013] Preferably, the interface module includes a four-wire interface and a five-wire interface, the four-wire interface is used to connect a four-wire fan, and the five-wire interface is used to connect a five-wire fan; the interface side of the compatible module includes a PWM_4 interface, a PWM+ interface and a PWM- interface; the four-wire interface is connected to the PWM_4 interface of the compatible module, and the five-wire interface is connected to the PWM+ interface and the PWM- interface of the compatible module.

[0014] Preferably, the compatible module includes a detection circuit, a forward PWM modulation unit, a reverse PWM modulation unit and a fifth AND gate; the input end of the detection circuit is suitable for receiving the PWM signal output by the main control module, and outputting a corresponding level signal according to the type of the judged PWM signal; the input end of the forward PWM modulation unit is suitable for receiving the PWM signal output by the main control module, the input end of the fifth AND gate is respectively connected to the output end of the forward PWM modulation unit and the output end of the detection circuit, and the output end of the fifth AND gate is connected to the PWM+ interface; the input end of the reverse PWM modulation unit is suitable for receiving the PWM signal output by the main control module and the level signal output by the detection circuit, and the reverse The output end of the PWM modulation unit is connected to the PWM-interface; for a five-wire fan, if the main control module outputs a forward PWM signal, the detection circuit outputs a high level, and the forward PWM modulation unit is suitable for modulating the forward PWM signal into a five-wire forward PWM signal, and transferring it to the PWM+ interface through the fifth AND gate; if the main control module outputs a customized inverse PWM signal, the detection circuit outputs a low level, so that the inverse PWM modulation unit modulates the customized inverse PWM signal into a five-wire inverse PWM signal and transfers it to the PWM-interface; for a four-wire fan, the PWM_4 interface is directly connected to the main control module to receive the PWM signal output by the main control module.

[0015] Preferably, the forward PWM signal and the customized reverse PWM signal output by the main control module correspond to different duty cycles and / or different frequencies; the detection circuit includes a duty cycle detection unit, a frequency detection unit and a logic judgment unit; the duty cycle detection unit is suitable for identifying PWM signals of different duty cycles output by the main control module; the frequency detection unit is suitable for identifying PWM signals of different frequencies output by the main control module; the logic judgment unit is suitable for making forward and reverse control judgments of the fan according to the identified PWM signal.

[0016] A working method of the above-mentioned fan compatible system includes the following steps: before the fan starts working, the type of the fan is identified by the main control module; based on the identified fan type, the compatible module transfers the control signal output by the main control module to the corresponding interface of the interface module.

[0017] Preferably, the main control module is suitable for first identifying a four-wire fan and a five-wire fan. If the fan type identified is a four-wire fan, the four-wire unidirectional fan and the four-wire bidirectional fan are further specifically identified. The identification of the four-wire fan and the five-wire fan includes the following process: the main control module is suitable for controlling the compatible module to transfer the set PWM signal to the first control interface of the interface module that is not connected to the four-wire fan; if the main control module receives the FG signal fed back by the interface module and it is consistent with the set value, it will determine that the connected fan is a five-wire fan; if the main control module does not receive the feedback from the interface module, The connected fan is identified as a four-wire fan by the fed FG signal; the specific identification of the four-wire fan includes the following process: the main control module first controls the compatible module to transfer the output PWM signal to the second control interface in the interface module connected to the four-wire fan; then the compatible module transfers the customized inverted PWM signal output by the main control module to the second control interface; the main control module calculates the current fan speed according to the received speed feedback signal FG, if the calculated fan speed is the same as the set value, the connected fan is identified as a four-wire bidirectional fan, otherwise the connected fan is identified as a four-wire unidirectional fan.

[0018] Compared with the prior art, the beneficial effects of this application are:

[0019] Compared with the traditional fan interface, this application can be compatible with both four-wire fans and five-wire fans by setting up a compatible module and an interface module. There is no need to design different hardware circuits and control methods for different fans, which can effectively save the design cost and maintenance cost of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of one embodiment of the fan compatible system in this application.

[0021] Figure 2 For this application Figure 1 A schematic diagram of the structure of a compatible module in the illustrated embodiment.

[0022] Figure 3 It is a structural schematic diagram of another embodiment of the fan-compatible system in the present application.

[0023] Figure 4 For this application Figure 3 A schematic diagram of the structure of a compatible module in the illustrated embodiment.

[0024] Figure 5 This is a schematic diagram of the control waveform for the five-wire fan to be reversed to forward in this application.

[0025] Figure 6This is a schematic diagram of the control waveform for the forward and reverse rotation of a five-wire fan in this application.

[0026] Figure 7 Schematic diagram of the working process of the fan compatible system in this application.

[0027] Figure 8 This is a waveform diagram for judging a four-wire fan and a five-wire fan in this application.

[0028] Fig. 9 This is a waveform diagram for judging a four-wire unidirectional fan and a four-wire bidirectional fan in this application.

[0029] In the figure: main control module 10, compatible module 11, five-wire interface 12, four-wire interface 13, logic judgment circuit 111, first NOT gate 1111, second NOT gate 1112, first AND gate 1113, second AND gate 1114, trigger 1115, forward and reverse selection circuit 112, third NOT gate 1121, third AND gate 1122, fourth AND gate 1123, switch module 113, detection circuit 114, duty cycle detection unit 1141, frequency detection unit 1142, logic judgment unit 1143, forward PWM modulation unit 115, reverse PWM modulation unit 116, fifth AND gate 117. DETAILED DESCRIPTION

[0030] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that in the description of this specification, the description of reference terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification. .

[0031] In the description of the present application, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of narrating the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and cannot be understood as limiting the specific scope of protection of the present application.

[0032] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0033] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0035] The terms "including" and "having" and any variations thereof in the specification and claims of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0036] One aspect of the present application provides a fan compatible system, such as Figure 1 and Figure 3 As shown, one preferred embodiment includes a main control module 10, a compatible module 11 and an interface module. The main control module 10 is mainly used to output a control signal for correspondingly controlling the fan. The interface module can be connected to the terminals of a four-wire fan or a five-wire fan through different numbers and / or different types of interfaces. The compatible module 11 includes an MCU side and an interface side, the MCU side can be connected to the main control module 10 for communication, and the interface side can be connected to the interface module for communication.

[0037] When controlling the operation of the fan, the main control module 10 can identify the type of fan connected to the interface module, and then the compatible module 11 can transfer the control signal output by the main control module 10 to the corresponding interface of the interface module according to the type of fan connected to the interface module. Compared with the traditional fan connection method, the present application can be compatible with both four-wire fans and five-wire fans by setting the compatible module 11 and the interface module; there is no need to design different hardware circuits and control methods for different fans, which can effectively save the design cost and maintenance cost of the system.

[0038] It is understandable that, from the background technology, the difference between a four-wire fan and a five-wire fan is that the four-wire fan lacks a reversal signal line. Therefore, when designing the interface module, it only needs to ensure that it can meet the connection requirements of the four-wire fan and the five-wire fan respectively; and for the signal transmission of the four-wire fan and the five-wire fan, it is only necessary to send the signal speed to the corresponding interface of the interface module through the compatible module 11; for example, when the interface module is connected to a four-wire fan, the compatible module 11 only needs to send the signal speed to the interface in the interface module that is connected to the four-wire fan. Therefore, through the transition connection of the compatible module 11, it is possible to perfectly match different types of fans through a hardware circuit, and thus there is no need to make different circuit boards to save design and operation and maintenance costs.

[0039] In this embodiment, Figure 1 and Figure 3 As shown, the interface module includes a four-wire interface 13 and a five-wire interface 12. The four-wire interface 13 is used to connect a four-wire fan, and the five-wire interface 12 is used to connect a five-wire fan. Both the four-wire interface 13 and the five-wire interface 12 are connected to the interface side of the compatible module 11; there are many specific ways for the interface side of the compatible module 11 to be connected to the four-wire interface 13 and the five-wire interface 12 respectively; for ease of understanding, three specific examples will be used for detailed description below.

[0040] Example 1: The interface side of the compatible module 11 is communicatively connected with the four-wire interface 13 and the five-wire interface 12 through completely different interfaces.

[0041] Example 2: Figure 1 As shown, the interface side of the compatible module 11 matches the five-wire interface 12 , and the four-wire interface 13 can be communicatively connected with the part of the interface that matches the five-wire interface 12 of the compatible module 11 .

[0042] Example 3: Figure 3As shown, the four-wire interface 13 and the five-wire interface 12 include a control interface and a common interface; wherein the control interface is used to control the direction of the fan, such as the reverse control interface corresponding to the four-wire fan and the forward and reverse interface corresponding to the five-wire fan; the common interface is used to supply power to the fan, ground it, and provide feedback on the fan's operating status, mainly including a grounding interface, a power supply interface, and a feedback interface. The common interface of the four-wire interface 13 and the common interface of the five-wire interface 12 are both matched with the compatible module 11 using the same interface; the compatible module 11 is matched with the control interface of the four-wire interface 13 and the control interface of the five-wire interface 12 respectively through completely different control interfaces.

[0043] It should be known that, for the above-mentioned example 1, the interface side of the compatible module 11 requires at least 9 interfaces; for the above-mentioned example 2, the interface side of the compatible module 11 requires at least 5 interfaces; for the above-mentioned example 3, the interface side of the compatible module 11 requires at least 6 interfaces. Therefore, in order to reduce the design difficulty and design cost of the compatible module 11, the structural design of the compatible module 11 in this application preferably adopts the above-mentioned example 2 and example 3; for the convenience of understanding, the following will be described in detail with respect to example 2 and example 3 through the specific embodiments of two fan compatible systems.

[0044] Embodiment 1:

[0045] like Figure 1 and Figure 2 As shown, the MCU side of the compatible module 11 receives the PWM signal, VCC_ctr signal, speed feedback signal FG and ground wire GND output by the main control module 10 through the corresponding interface. The interface side of the compatible module 11 includes a PWM+ interface, a PWM- interface, a VCC_out interface, an FG interface and a GND interface. Among them, the VCC_out interface, the FG interface and the GND interface are respectively used to connect to the ordinary interfaces corresponding to the four-wire interface 13 and the five-wire interface 12; the four-wire interface 13 is also connected to the PWM+ interface of the compatible module 11, and the five-wire interface 12 is also connected to the PWM+ interface and the PWM- interface of the compatible module 11.

[0046] When a four-wire fan is connected to the four-wire interface 13, the compatible module 11 can transfer the PWM signal output by the main control module 10 to the four-wire fan through the PWM+ interface to control the rotation of the fan. When a five-wire fan is connected to the five-wire interface 12, if the five-wire fan needs to rotate forward, the compatible module 11 can transfer the PWM signal output by the main control module 10 to the five-wire fan through the PWM+ interface to control the forward rotation of the fan; if the five-wire fan needs to rotate reversely, the compatible module 11 can transfer the PWM signal output by the main control module 10 to the five-wire fan through the PWM- interface to control the reverse rotation of the fan.

[0047] It is important to know that the fan terminals are usually directly pressed by the manufacturer when it leaves the factory, that is, the terminal structures of four-wire fans and five-wire fans are different. Therefore, the four-wire interface 13 and the five-wire interface 12 are two independently set physical interfaces, so that when connecting a four-wire fan or a five-wire fan, the fan terminals can be connected through the corresponding physical interface. Of course, if the terminal structure of the four-wire fan can be customized as a five-wire terminal (the reverse signal interface is not wired), the four-wire interface 13 and the five-wire interface 12 can be set on the same physical interface.

[0048] In this embodiment, based on the specific connection mode between the compatible module 11 and the interface module, there are multiple specific structures of the compatible module 11. For the sake of easy understanding, one of the structures will be described in detail below. Figure 2 As shown, the compatible module 11 includes a logic judgment circuit 111 and a forward and reverse selection circuit 112. The logic judgment circuit 111 can receive the control signal output by the main control module 10 to determine the direction in which the fan needs to rotate, and output different level signals based on the different directions in which the fan needs to rotate. The forward and reverse selection circuit 112 can receive the level signal output by the logic judgment circuit 111 and the control signal output by the main control module 10, and forward the control signal to the PWM+ interface or the PWM- interface based on the received signal.

[0049] Specifically, when the four-wire interface 13 of the interface module is connected to a four-wire fan, the forward and reverse selection circuit 112 can transfer the control signal to the PWM+ interface; that is, the PWM+ interface of the compatible module 11 constantly transfers the PWM signal output by the main control module 10, and the PWM- interface of the compatible module 11 is constantly at a low level. When the interface module is connected to a five-wire fan, the forward and reverse selection circuit 112 can transfer the control signal to one of the PWM+ interface and the PWM- interface, and transfer the low-level signal to the other interface; that is, when the five-wire fan needs to be converted to forward rotation, the forward and reverse selection circuit 112 can transfer the PWM signal output by the main control module 10 to the PWM+ interface, and at this time the PWM- interface of the compatible module 11 is at a low level; if the five-wire fan needs to be converted to reverse rotation, the forward and reverse selection circuit 112 can transfer the PWM signal output by the main control module 10 to the PWM- interface, and at this time the PWM+ interface of the compatible module 11 is at a low level.

[0050] It should be known that the speed feedback signal FG output by the main control module 10 is directly connected to the input and output through the compatible module 11, that is, the interface module can be directly connected to the FG signal line of the main control module 10 to communicate the speed feedback signal FG. Correspondingly, the ground line GND of the main control module 10 is also directly connected to the interface module through the compatible module 11 to ensure the safety of the fan when it is working.

[0051] It should also be known that the VCC_crt signal output by the main control module 10 is a power supply control signal for the fan, and the compatible module 11 further includes a switch module 113, which is controlled by the VCC_crt signal output by the main control module 10, and the output end of the switch module 113 can be connected to the VCC_out interface. Thus, the switch module 113 controls the VCC_out interface to output the VCC voltage or low level according to the level state of the VCC_crt signal to ensure that the fan works normally.

[0052] In this embodiment, there are many specific structures of the logic judgment circuit 111 that can realize the above functions. For the sake of easy understanding, the following will be described in detail using one of the structures. Figure 2 As shown, the control signal output by the main control module 10 includes a PWM signal and a VCC_ctl signal; the logic judgment circuit 111 includes a gate circuit and a trigger 1115, the input end of the gate circuit can receive the PWM signal and the VCC_ctl signal, the output end of the gate circuit is connected to the input end of the trigger 1115, and the output end of the trigger 1115 is connected to the input end of the forward and reverse selection circuit 112.

[0053] It should be noted that there are three main working states of the fan at the next moment. The first state is that the fan will change from reverse rotation to forward rotation at the next moment; the second state is that the fan will change from forward rotation to reverse rotation at the next moment; the third state is that the fan will maintain the operating state at the current moment at the next moment. Based on the working state of the fan at the next moment, specific operating rules can be formulated, and the specific formulation of the operating rules is related to the specific type of trigger 1115. There are many types of trigger 1115, such as D trigger and RS trigger. For the convenience of description, this embodiment preferably uses an RS trigger for trigger 1115, and the RS trigger used in this embodiment has a low-level holding function; the specific structure and working principle of the RS trigger are well-known technologies to those skilled in the art, so they will not be elaborated in detail here.

[0054] It should be known that the VCC_crt signal output by the main control module 10 is the power supply control signal of the fan, and the PWM signal output by the main control module 10 is the driving signal of the fan. After selecting the trigger 1115, the specific operation rules can be formulated in combination with the function of the control signal output by the main control module 10 as follows:

[0055] When the fan needs to switch to forward rotation at the next moment, the VCC_ctl signal and PWM signal output by the main control module 10 are both low level, and the trigger 1115 will output a low level. When the fan needs to switch to reverse rotation at the next moment, the VCC_ctl signal output by the main control module 10 is low level, and the output PWM signal is high level, and the trigger 1115 will output a high level. When the fan continues to work normally at the next moment, the VCC_ctl signal output by the main control module 10 is high level, and the trigger 1115 is in a hold state to maintain the level signal output at the previous moment.

[0056] Based on the above specific operating rules, there are many specific structures of gate circuits. For easy understanding, one of the structures will be given below for detailed description. Figure 2 As shown, the gate circuit includes a first NOT gate 1111, a second NOT gate 1112, a first AND gate 1113 and a second AND gate 1114. The input end of the first NOT gate 1111 can receive the VCC_ctl signal, and the input end of the first AND gate 1113 can receive the output signal of the first NOT gate 1111 and the PWM signal respectively. The input end of the second NOT gate 1112 can receive the PWM signal, and the input end of the second AND gate 1114 can receive the output signals of the first NOT gate 1111 and the second NOT gate 1112 respectively. The output end of the first AND gate 1113 and the output end of the second AND gate 1114 are both connected to the input end of the trigger 1115.

[0057] In this embodiment, there are many specific structures of the forward and reverse selection circuit 112 that can realize the above functions. For the sake of easy understanding, the following will be described in detail using one of the structures. Figure 2 As shown, the forward and reverse selection circuit 112 includes a third NOT gate 1121, a third AND gate 1122 and a fourth AND gate 1123. The input end of the third NOT gate 1121 can receive the output signal of the logic judgment circuit 111, the input end of the third AND gate 1122 can receive the output signal of the third NOT gate 1121 and the PWM signal respectively, and the output end of the third AND gate 1122 is connected to the PWM+ interface. The input end of the fourth AND gate 1123 can receive the output signal of the logic judgment circuit 111 and the PWM signal respectively, and the output end of the fourth AND gate 1123 is connected to the PWM- interface.

[0058] For a five-wire fan, if the fan needs to be switched to forward rotation, the third AND gate 1122 can output a PWM signal to the PWM+ interface, and the fourth AND gate 1123 can output a low level to the PWM- interface; if the fan needs to be switched to reverse rotation, the third AND gate 1122 can output a low level to the PWM+ interface, and the fourth AND gate 1123 can output a PWM signal to the PWM- interface. For a four-wire fan, the third AND gate 1122 can constantly output a PWM signal to the PWM+ interface, and the fourth AND gate 1123 can constantly output a low level to the PWM- interface.

[0059] For ease of understanding, the specific working process of the compatible module 11 will be described in detail below for a four-wire fan and a five-wire fan.

[0060] 1. For five-wire fans.

[0061] (1) If Figure 5 As shown, assuming that the fan is in reverse state at the current moment, the PWM signal and VCC_ctl signal output by the main control module 10 are both high level, and the output of the logic judgment circuit 111 corresponds to the output of the trigger 1115 is high level. When the direction of the fan needs to be changed, the fan needs to be stopped first, and then restarted to change the direction. The downtime is Figure 5 Medium 5 to 6 During the downtime, the PWM signal and VCC_ctl signal output by the main control module 10 are both at low level. Figure 2 As shown, the first NOT gate 1111 and the second NOT gate 1112 will both output a high level, the first AND gate 1113 will output a low level, the second NOT gate 1112 will output a high level, and the trigger 1115 will output a low level. During the downtime, since the VCC_ctl signal is at a low level, the VCC_out interface of the compatible module 11 will output a low level, so that the fan is in a downtime state.

[0062] After the downtime is over, if Figure 5 As shown, at t 6 At this moment, the PWM signal and VCC_ctl signal output by the main control module 10 are both at high level. Figure 2As shown, the first NOT gate 1111 and the second NOT gate 1112 both output a low level, and then the first AND gate 1113 and the second AND gate 1114 also output a low level, so that the trigger 1115 will maintain the low level output at the previous moment. At this time, the third NOT gate 1121 will output a high level, and the third AND gate 1122 will output a high-level PWM signal to the PWM+ interface, and the fourth AND gate 1123 will output a low level to the PWM- interface. At the same time, the VCC_ctl signal is a high level, so that the VCC_out interface of the compatible module 11 outputs a VCC signal to the fan, so that the fan will rotate in the forward direction with power.

[0063] (2) If Figure 6 As shown in the figure, when the fan needs to change from forward rotation to reverse rotation again, the fan needs to be stopped again and then restarted in reverse direction. Figure 6 Medium 7 to 8 During the downtime, the PWM signal output by the main control module 10 is high level, and the VCC_ctl signal output is low level. Figure 2 As shown, the first NOT gate 1111 will output a high level, the second NOT gate 1112 will output a low level, and then the first AND gate 1113 will output a high level, the second AND gate 1114 will output a low level, and the trigger 1115 will output a high level. During the downtime, since the VCC_ctl signal is at a low level, the VCC_out interface of the compatible module 11 will output a low level, so that the fan is in a downtime state.

[0064] After the downtime is over, if Figure 6 As shown, at t 8 At this moment, the PWM signal and VCC_ctl signal output by the main control module 10 are both at high level. Figure 2 As shown, the first NOT gate 1111 and the second NOT gate 1112 both output a low level, and then the first AND gate 1113 and the second AND gate 1114 also output a low level, so that the trigger 1115 will maintain the high level output at the previous moment. At this time, the third NOT gate 1121 will output a low level, and the third AND gate 1122 will output a low level to the PWM+ interface, and the fourth AND gate 1123 will output a high level PWM signal to the PWM- interface. At the same time, the VCC_ctl signal is a high level, so that the VCC_out interface of the compatible module 11 outputs a VCC signal to the fan, so that the fan will rotate in the reverse direction of power.

[0065] 2. For four-wire fans.

[0066] It should be noted that four-wire fans generally include four-wire bidirectional fans and four-wire unidirectional fans. Four-wire bidirectional fans can rotate forward and reverse, while four-wire unidirectional fans can only rotate forward and cannot reverse.

[0067] (1) Before switching the four-wire bidirectional fan from forward to reverse or from reverse to forward, the main control module 10 pulls the output PWM signal and VCC_ctl signal down to a low level. Figure 2 As shown, the first NOT gate 1111 and the second NOT gate 1112 will both output a high level, the first AND gate 1113 will output a low level, the second NOT gate 1112 will output a high level, and thus the trigger 1115 will output a low level. After the switching is completed, the main control module 10 pulls the VCC_ctl signal to a high level so that the trigger 1115 maintains the low level output at the previous moment. At this time, according to the topological structure of the forward and reverse selection circuit 112, the fourth AND gate 1123 constantly outputs a low level to the PWM-interface, and the third AND gate 1122 transfers the PWM signal to the PWM+ interface; if the four-wire bidirectional fan needs to be converted to forward rotation at the next moment, the PWM signal can be pulled up to a high level after the switching is completed, and if the four-wire bidirectional fan needs to be converted to reverse rotation at the next moment, the PWM signal can be kept at a low level after the switching is completed.

[0068] (2) Before switching the four-wire unidirectional fan to forward rotation, the main control module 10 pulls both the output PWM signal and the VCC_ctl signal down to a low level. Figure 2 As shown, the first NOT gate 1111 and the second NOT gate 1112 will both output a high level, the first AND gate 1113 will output a low level, the second NOT gate 1112 will output a high level, and the trigger 1115 will output a low level. After the switching is completed, the main control module 10 pulls the VCC_ctl signal to a high level so that the trigger 1115 maintains the low level output at the previous moment. At this time, according to the topological structure of the forward and reverse selection circuit 112, the fourth AND gate 1123 constantly outputs a low level to the PWM-interface, and the third AND gate 1122 performs normal forwarding and output of the PWM signal to the PWM+interface.

[0069] Embodiment 2:

[0070] The difference between this embodiment and the first embodiment is that Figure 3 and Figure 4As shown, the interface side of the compatible module 11 includes a PWM_4 interface, a PWM+ interface, a PWM- interface, a VCC_out interface, an FG interface, and a GND interface. Among them, the VCC_out interface, the FG interface, and the GND interface are respectively used to connect with the common interfaces corresponding to the four-wire interface 13 and the five-wire interface 12; the four-wire interface 13 is also connected to the PWM_4 interface of the compatible module 11, and the five-wire interface 12 is also connected to the PWM+ interface and the PWM- interface of the compatible module 11.

[0071] When a four-wire fan is connected to the four-wire interface 13, the compatible module 11 can transfer the PWM signal output by the main control module 10 to the four-wire fan through the PWM_4 interface to control the rotation of the fan. When a five-wire fan is connected to the five-wire interface 12, if the five-wire fan needs to rotate forward, the compatible module 11 can transfer the PWM signal output by the main control module 10 to the five-wire fan through the PWM+ interface to control the forward rotation of the fan; if the five-wire fan needs to rotate reversely, the compatible module 11 can transfer the PWM signal output by the main control module 10 to the five-wire fan through the PWM- interface to control the reverse rotation of the fan.

[0072] In this embodiment, based on the specific connection mode between the compatible module 11 and the interface module, there are multiple specific structures of the compatible module 11. For the sake of easy understanding, one of the structures will be described in detail below. Figure 4 As shown, the compatible module 11 includes a detection circuit 114, a forward PWM modulation unit 115, an inverse PWM modulation unit 116 and a fifth AND gate 117. The input end of the detection circuit 114 can receive the PWM signal output by the main control module 10, and output a corresponding level signal according to the type of the judged PWM signal; the input end of the forward PWM modulation unit 115 can receive the PWM signal output by the main control module 10, the input end of the fifth AND gate 117 is respectively connected to the output end of the forward PWM modulation unit 115 and the output end of the detection circuit 114, and the output end of the fifth AND gate 117 is connected to the PWM+ interface. The input end of the inverse PWM modulation unit 116 can respectively receive the PWM signal output by the main control module 10 and the level signal output by the detection circuit 114, and the output end of the inverse PWM modulation unit 116 is connected to the PWM- interface.

[0073] For the rotation control of the five-wire fan, when the main control module 10 outputs a forward PWM signal, the detection circuit 114 can output a high level, and the forward PWM modulation unit 115 can modulate the forward PWM signal into a five-wire forward PWM signal, and transfer it to the PWM+ interface through the fifth AND gate 117. When the main control module 10 outputs a customized reverse PWM signal, the detection circuit 114 outputs a low level, so that the reverse PWM modulation unit 116 modulates the customized reverse PWM signal into a five-wire reverse PWM signal and transfers it to the PWM-interface, and the fifth AND gate 117 will output a low level to the PWM+ interface.

[0074] For the rotation control of the four-wire fan, the PWM_4 interface can be directly connected to the main control module 10 to receive the PWM signal output by the main control module 10. If the four-wire fan needs to rotate forward, it only needs to output the forward PWM signal to the PWM_4 interface; if the four-wire bidirectional fan needs to rotate reversely, it only needs to output the customized reverse PWM signal to the PWM_4 interface.

[0075] It should be known that the types of the forward PWM signal and the customized reverse PWM signal can be distinguished by different duty cycles or different frequencies. Of course, the types of PWM signals can also be distinguished by other methods. For ease of understanding, the following will briefly describe the process of distinguishing the types of PWM signals using duty cycles as an example.

[0076] Specifically, the duty cycle corresponding to the forward PWM signal can be set to 0.4, and the duty cycle of the customized reverse PWM signal can be set to 0.6. Then the detection circuit 114 can set a duty cycle threshold of 0.5. When the duty cycle of the PWM signal received by the detection circuit 114 is less than the set duty cycle threshold, it can be considered that the current PWM signal is a forward PWM signal, and the detection circuit 114 will output a high level at this time; when the duty cycle of the PWM signal received by the detection circuit 114 is greater than the set duty cycle threshold, it can be considered that the current PWM signal is a customized reverse PWM signal, and the detection circuit 114 will output a low level at this time.

[0077] In this embodiment, based on the above-mentioned PWM signal type distinction method, such as Figure 4 As shown, the specific structure of the detection circuit 114 includes a duty cycle detection unit 1141, a frequency detection unit 1142 and a logic judgment unit 1143. The duty cycle detection unit 1141 can identify PWM signals with different duty cycles output by the main control module 10; the frequency detection unit 1142 can identify PWM signals with different frequencies output by the main control module 10; and the logic judgment unit 1143 can make a forward and reverse control judgment of the fan according to the identified PWM signal.

[0078] It can be understood that if the main control module 10 outputs PWM signals with different duty cycles for different switching directions of the fan, the duty cycle detection unit 1141 of the detection circuit 114 will be started and identify the duty cycle of the PWM signal; the logic judgment unit 1143 will perform a threshold comparison on the identified duty cycle to determine the control direction required by the fan, that is, whether the PWM signal is a forward PWM signal or a customized reverse PWM signal; when the identified PWM signal is a forward PWM signal, the logic judgment unit 1143 will output a high level, and when the identified PWM signal is a customized reverse PWM signal, the logic judgment unit 1143 will output a low level. Similarly, if the main control module 10 outputs PWM signals of different frequencies for different switching directions of the fan, the frequency detection unit 1142 of the detection circuit 114 will be started and the frequency of the PWM signal will be identified; the logic judgment unit 1143 will perform a threshold comparison for the identified frequency to determine the control direction required by the fan, that is, whether the PWM signal is a forward PWM signal or a customized reverse PWM signal; when the identified PWM signal is a forward PWM signal, the logic judgment unit 1143 will output a high level, and when the identified PWM signal is a customized reverse PWM signal, the logic judgment unit 1143 will output a low level. Of course, the main control module 10 can also output PWM signals of different frequencies and different duty cycles for different switching directions of the fan, and the detection circuit 114 can simultaneously detect and identify the duty cycle and frequency and perform threshold judgments separately.

[0079] It should be known that the specific structures and working principles of the duty cycle detection unit 1141, the frequency detection unit 1142, and the logic judgment unit 1143 are well known to those skilled in the art, so they will not be elaborated in detail here. The duty cycle detection unit 1141 can recognize the duty cycle by comparing it with the reference voltage after filtering, and the reference voltage can be determined according to the waveform of the customized inversion PWM signal. The frequency detection unit 1142 can recognize the frequency by using a time base chip and a counter chip. The level output of the logic judgment unit 1143 depends on the customization method of the customized inversion PWM signal. If the logic judgment unit 1143 only judges one of the duty cycle and the frequency, an OR gate circuit can be preferably used; that is, the duty cycle and the frequency are both inputs of the OR gate circuit, and the OR gate circuit always has only one input involved in the logic judgment; when the duty cycle meets the threshold condition or the frequency meets the threshold condition, the OR gate circuit can output a high level, otherwise the OR gate circuit will output a low level. If the logic judgment unit 1143 needs to judge the duty cycle and frequency at the same time, an AND gate circuit can be preferably used; that is, the duty cycle and frequency are both inputs of the AND gate circuit, and only when the inputs meet the threshold conditions will the AND gate circuit output a high level, otherwise the AND gate circuit will output a low level.

[0080] Another aspect of the present application provides a working method of the above-mentioned fan compatible system, such as Figure 7 As shown, one preferred embodiment includes the following steps: before the fan starts to work normally, the type of the fan is identified by the main control module 10. Based on the identified fan type, the compatible module 11 forwards the control signal output by the main control module 10 to the corresponding interface of the interface module.

[0081] It can be understood that, from the above content, the types of fans mainly include four-wire fans and five-wire fans; among them, four-wire fans can also be specifically divided into four-wire unidirectional fans and four-wire bidirectional fans. Therefore, the main step of this embodiment is to first distinguish whether the fan is a four-wire fan or a five-wire fan; if the fan is a four-wire fan, it will continue to distinguish whether the fan is a four-wire unidirectional fan or a four-wire bidirectional fan. After identifying the specific type of the fan, the compatible module 11 can be controlled to forward the control signal output by the main control module 10 to the corresponding interface of the interface module.

[0082] It should be known that, from the specific structural description of the compatible module 11 mentioned above, there are non-overlapping interface areas between the four-wire interface 13 and the five-wire interface 12 and the compatible module 11; therefore, the distinction between a four-wire fan and a five-wire fan can be made by sending a corresponding PWM signal to an interface that is not shared by the two, and then judging the fan wire type based on the fan's response. After determining that it is a four-wire fan, since the difference between a four-wire unidirectional fan and a four-wire bidirectional fan is that a four-wire unidirectional fan cannot be reversed, it is only necessary to send a PWM signal for reversal to the corresponding control interface, and then judge whether it is a four-wire unidirectional fan or a four-wire bidirectional fan based on the fan's steering response. For ease of understanding, the fan type identification will be described in detail below.

[0083] In this embodiment, Figure 8 As shown, the identification of four-wire fans and five-wire fans includes the following process: the main control module 10 can control the compatible module 11 to transfer the set PWM signal to the first control interface in the interface module that is not connected to the four-wire fan; if the main control module 10 receives the FG signal fed back by the interface module and it is consistent with the set value, it will be determined that the connected fan is a five-wire fan; if the main control module 10 does not receive the FG signal fed back by the interface module, it will be determined that the connected fan is a four-wire fan.

[0084] It is understandable that, for the above-mentioned embodiment 1, the first control interface is a PWM interface. Figure 8 As shown, at t 0 At this moment, the main control module 10 can control the VCC_ctl signal to be low level and the PWM signal to be high level; at this time, the compatible module 11 can transfer the PWM signal to the PWM-interface. 1At this moment, the main control module 10 can set a fan reverse speed v and output a corresponding PWM signal until t 2 At the end of time t 1 to 2 The main control module 10 can monitor the feedback FG signal within the time. The FG signal can reflect the current fan speed and can return square wave signals of different frequencies according to the different speeds. The main control module 10 can calculate whether the current fan speed is consistent with the set value v according to the frequency of the square wave returned by the FG signal; if the speed calculated according to the feedback FG signal is consistent with the set value v, it can be determined that the connected fan is a five-wire fan; if the feedback FG signal is not detected, it can be determined that the connected fan is a four-wire fan. For the above-mentioned embodiment 2, the first control interface can be a PWM+ interface or a PWM-interface; taking the first control interface using the PWM-interface as an example, the specific identification process can refer to the identification process of the above-mentioned embodiment 1.

[0085] In this embodiment, Fig. 9 As shown, the specific identification of the four-wire fan includes the following process: the main control module 10 first controls the compatible module 11 to forward the output PWM signal to the second control interface in the interface module connected to the four-wire fan. Then the compatible module 11 forwards the customized reverse PWM signal output by the main control module 10 to the second control interface. The main control module 10 calculates the current fan speed based on the received speed feedback signal FG. If the calculated fan speed is the same as the set value, the connected fan will be identified as a four-wire bidirectional fan, otherwise the connected fan will be identified as a four-wire unidirectional fan.

[0086] It can be understood that, for the above-mentioned embodiment 1, the second control interface is a PWM+ interface. Fig. 9 As shown, at t 3 to 4 During the time period, the main control module 10 controls the compatible module 11 to transfer the PWM signal to the PWM+ interface, and then the main control module 10 can set a reverse speed v 0 And output a corresponding customized inverse PWM signal; then the main control module 10 can calculate whether the current fan speed is consistent with the set value v according to the feedback FG signal 0 If the calculated fan speed is the same as the set value, the connected fan is identified as a four-wire bidirectional fan, otherwise the connected fan is identified as a four-wire unidirectional fan. For the above-mentioned embodiment 2, the second control interface is the PWM_4 interface, and the specific identification process can refer to the identification process of the second control interface as the PWM+ interface.

[0087] It should be known that the customized inversion PWM signal output by the main control module 10 can be customized for the duty cycle of the signal, or the frequency of the signal, or both the duty cycle and frequency of the signal can be customized. The specific selection can be made according to the actual needs of technical personnel in this field.

[0088] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A fan compatible system, characterized in that: include: Main control module; The main control module is suitable for outputting a control signal of the fan; Interface module; The interface module is suitable for connecting to the terminals of a four-wire fan or a five-wire fan respectively through different numbers and / or different types of interfaces; and A compatible module; the MCU side of the compatible module is communicatively connected to the main control module, and the interface side of the compatible module is communicatively connected to the interface module; the compatible module is adapted to forward the control signal output by the main control module to the corresponding interface of the interface module according to the type of fan connected to the interface module; The interface module includes a four-wire interface and a five-wire interface, the four-wire interface is used to connect a four-wire fan, and the five-wire interface is used to connect a five-wire fan; The interface side of the compatible module includes a PWM+ interface and a PWM- interface; The four-wire interface is connected to the PWM+ interface of the compatible module, and the five-wire interface is connected to the PWM+ interface and the PWM- interface of the compatible module; The compatible modules include: A logic judgment circuit; the logic judgment circuit is adapted to receive the control signal output by the main control module to judge the direction in which the fan needs to rotate, and output different level signals based on different directions of the fan rotation switching; and Forward and reverse selection circuit; the forward and reverse selection circuit is suitable for receiving the level signal output by the logic judgment circuit and the control signal output by the main control module, and forwarding the control signal to the PWM+ interface or the PWM- interface based on the received signal.

2. The fan compatible system according to claim 1, characterized in that: The four-wire interface and the five-wire interface are respectively arranged at independent physical interfaces, so that the four-wire fan and the five-wire fan are connected to the corresponding physical interfaces through terminals; Alternatively, the four-wire interface and the five-wire interface are arranged at the same physical interface, and both the four-wire fan and the five-wire fan are connected to the same physical interface by using five-wire terminals.

3. The fan compatible system according to claim 1, characterized in that: The control signal output by the main control module includes a PWM signal and a VCC_ctl signal; the logic judgment circuit includes: Gate circuit; the input end of the gate circuit is suitable for receiving a PWM signal and a VCC_ctl signal; and A trigger; the input end of the trigger is connected to the output end of the gate circuit, and the output end of the trigger is connected to the input end of the forward and reverse selection circuit; For a five-wire fan, if the fan switches forward, the VCC_ctl signal and the PWM signal are both low, and the trigger will output a low level; if the fan switches reverse, the VCC_ctl signal is low, the PWM signal is high, and the trigger will output a high level; For a four-wire fan, if the fan performs a direction switching, the VCC_ctl signal and the PWM signal are both at a low level, and then the trigger will output a low level.

4. The fan compatible system according to claim 3, characterized in that: The forward and reverse selection circuit comprises: A third NOT gate; the input end of the third NOT gate is suitable for receiving the output signal of the logic judgment circuit; A third AND gate; the input end of the third AND gate is adapted to receive the output signal of the third NOT gate and the PWM signal respectively, and the output end of the third AND gate is connected to the PWM+ interface; and A fourth AND gate; the input end of the fourth AND gate is suitable for receiving the output signal of the logic judgment circuit and the PWM signal respectively, and the output end of the fourth AND gate is connected to the PWM-interface; For a five-wire fan, if the fan needs to be switched to forward rotation, the third AND gate is suitable for outputting a PWM signal to the PWM+ interface, and the fourth AND gate is suitable for outputting a low level to the PWM- interface; if the fan needs to be switched to reverse rotation, the third AND gate is suitable for outputting a low level to the PWM+ interface, and the fourth AND gate is suitable for outputting a PWM signal to the PWM- interface; For a four-wire fan, the third AND gate is suitable for constantly outputting a PWM signal to the PWM+ interface, and the fourth AND gate is suitable for constantly outputting a low level to the PWM- interface.

5. The fan compatible system according to claim 1, characterized in that: The interface module includes a four-wire interface and a five-wire interface, the four-wire interface is used to connect a four-wire fan, and the five-wire interface is used to connect a five-wire fan; The interface side of the compatible module includes a PWM_4 interface, a PWM+ interface and a PWM- interface; The four-wire interface is connected to the PWM_4 interface of the compatible module, and the five-wire interface is connected to the PWM+ interface and the PWM- interface of the compatible module.

6. The fan compatible system according to claim 5, characterized in that: The compatible modules include: Detection circuit; the input end of the detection circuit is suitable for receiving the PWM signal output by the main control module, and outputting a corresponding level signal according to the type of the determined PWM signal; A forward PWM modulation unit; the input end of the forward PWM modulation unit is suitable for receiving the PWM signal output by the main control module; A fifth AND gate; the input end of the fifth AND gate is respectively connected to the output end of the forward PWM modulation unit and the output end of the detection circuit, and the output end of the fifth AND gate is connected to the PWM+ interface; and An inverted PWM modulation unit; the input end of the inverted PWM modulation unit is suitable for receiving the PWM signal output by the main control module and the level signal output by the detection circuit respectively, and the output end of the inverted PWM modulation unit is connected to the PWM-interface; For a five-wire fan, if the main control module outputs a forward PWM signal, the detection circuit outputs a high level, and the forward PWM modulation unit is suitable for modulating the forward PWM signal into a five-wire forward PWM signal, and forwarding it to the PWM+ interface through the fifth AND gate; if the main control module outputs a customized reverse PWM signal, the detection circuit outputs a low level, so that the reverse PWM modulation unit modulates the customized reverse PWM signal into a five-wire reverse PWM signal and forwards it to the PWM- interface; For a four-wire fan, the PWM_4 interface is directly connected to the main control module to receive the PWM signal output by the main control module.

7. The fan compatible system according to claim 6, characterized in that: The forward PWM signal and the customized reverse PWM signal output by the main control module have different corresponding duty cycles and / or different corresponding frequencies; The detection circuit comprises: A duty cycle detection unit; the duty cycle detection unit is suitable for identifying PWM signals with different duty cycles output by the main control module; A frequency detection unit; the frequency detection unit is suitable for identifying PWM signals of different frequencies output by the main control module; and Logic judgment unit: The logic judgment unit is suitable for making a forward and reverse control judgment of the fan according to the identified PWM signal.

8. A working method of a fan compatible system according to any one of claims 1 to 7, characterized in that: The steps include: Before the fan starts working, the type of the fan is identified by the main control module; Based on the identified fan type, the compatible module forwards the control signal output by the main control module to the corresponding interface of the interface module.

9. The operating method of the fan compatible system according to claim 8, characterized in that: The main control module is suitable for first identifying a four-wire fan and a five-wire fan, and if the identified fan type is a four-wire fan, continuing to specifically identify a four-wire unidirectional fan and a four-wire bidirectional fan; The identification of four-wire fans and five-wire fans includes the following process: The main control module is adapted to control the compatible module to transfer a set PWM signal to a first control interface in the interface module that is not connected to a four-wire fan; If the main control module receives the FG signal fed back by the interface module and it matches the set value, it will determine that the connected fan is a five-wire fan; If the main control module does not receive the FG signal fed back by the interface module, it will determine that the connected fan is a four-wire fan; The specific identification of the four-wire fan includes the following process: The main control module first controls the compatible module to transfer the output PWM signal to the second control interface connected to the four-wire fan in the interface module; Then the compatible module transfers the customized inversion PWM signal output by the main control module to the second control interface; The main control module calculates the current fan speed based on the received speed feedback signal FG. If the calculated fan speed is the same as the set value, the connected fan is identified as a four-wire bidirectional fan. Otherwise, the connected fan is identified as a four-wire unidirectional fan.

Images