Fan control system and range hood

Abstract

The utility model relates to the technical field of range hoods, and discloses a fan control system and a range hood, a first end and a second end of a first common mode inductor are connected with an input power supply, and a third end and a fourth end of the first common mode inductor are connected with a voltage conversion circuit; the first capacitor is connected between the first end and the second end of the first common mode inductor, and the second capacitor is connected between the third end and the fourth end of the first common mode inductor; the input end of the rectifying circuit is connected with the third end and the fourth end of the first common mode inductor; one end of the first inductor is connected with the output end of the rectification circuit, and the other end is connected with the transformation circuit; one end of the third capacitor is connected with one end of the first inductor, and the other end is connected with the second capacitor and grounded; and the driving module is connected with the direct current motor through the second common mode inductor. The first capacitor, the second capacitor and the first common-mode inductor form a filter circuit, so that the filtering effect is ensured, and the cost is reduced; the second common mode inductor is used for replacing a magnetic ring on a direct current motor line, so that the cost is reduced while the motor interference is filtered.

Description

TECHNICAL FIELD

[0001] The utility model relates to a range hood technology field especially to a fan control system and range hood. BACKGROUND

[0002] Compared with the AC range hood control system, the DC range hood control system has the advantages of low power consumption, high maximum static pressure, and easy control of air volume and noise.

[0003] At present, the circuit of the DC range hood control system is relatively complex, needs to have multiple filter circuits, and cooperates with the magnetic ring formed by manual winding in the motor, resulting in high manufacturing cost of the whole circuit. SUMMARY

[0004] The first technical problem solved by the utility model is to provide a fan control system, which effectively solves the problems of complex circuit and high cost of the DC range hood control system.

[0005] The second technical problem solved by the utility model is to provide a range hood, which effectively solves the problems of complex circuit and high cost of the DC range hood control system.

[0006] The first technical problem is solved by the following technical scheme:

[0007] A fan control system, comprising: a power module and a driving module, the power module and the driving module being connected; the power module comprising a filter circuit and a voltage conversion circuit;

[0008] The filter circuit comprises a first capacitor, a second capacitor, and a first common-mode inductor; the first end and the second end of the first common-mode inductor are connected with the input power supply of the power module, the third end and the fourth end of the first common-mode inductor are connected with the voltage conversion circuit; the first capacitor is connected between the first end and the second end of the first common-mode inductor, and the second capacitor is connected between the third end and the fourth end of the first common-mode inductor;

[0009] The voltage conversion circuit comprises a rectifier circuit, a first inductor, a third capacitor, and a transformer circuit; the input end of the rectifier circuit is connected with the third end and the fourth end of the first common-mode inductor; one end of the first inductor is connected with the output end of the rectifier circuit, and the other end of the first inductor is connected with the transformer circuit; one end of the third capacitor is connected with one end of the first inductor, and the other end of the third capacitor is connected with the second capacitor and grounded;

[0010] The driving module is connected with the DC motor through a second common-mode inductor.

[0011] The fan control system has the beneficial effects that: the first capacitor, the second capacitor and the first common mode inductor constitute a filter circuit, the first inductor and the third capacitor connected after the rectifier circuit make further filtering, the circuit is simplified and the cost is reduced while the filtering effect is ensured; the second common mode inductor is connected between the driving module and the DC motor, the second common mode inductor is used to replace the magnetic ring on the DC motor line, the cost is reduced while the motor interference is filtered out, and the second common mode inductor is directly connected in the circuit, compared with the magnetic ring buckled on the DC motor line, the reliability and stability are higher.

[0012] In one of the embodiments, the power module further comprises a variable frequency control power supply circuit and a primary side feedback controller.

[0013] The transformer comprises a first winding, a second winding and a third winding; the first winding and the second winding are located on the primary side of the transformer, and the third winding is located on the secondary side of the transformer.

[0014] The first winding is connected with the rectifier circuit; the third winding is connected with the output end of the transformer circuit.

[0015] The first end of the second winding is connected with the power input port of the primary side feedback controller and the variable frequency control power supply circuit respectively, and the second end of the second winding is grounded.

[0016] In one of the embodiments, the first end of the first winding is connected with the first output end of the rectifier circuit through the first inductor, and the second output end of the rectifier circuit is grounded through the third capacitor.

[0017] The second end of the first winding is connected with the output end of the primary side feedback controller.

[0018] In one of the embodiments, the variable frequency control power supply circuit comprises a voltage stabilizing chip and an isolation device.

[0019] The first end of the isolation device is connected with the variable frequency control signal, and the second end and the third end of the isolation device are grounded respectively.

[0020] The input end of the voltage stabilizing chip is connected with the first end of the second winding, the power input port of the primary side feedback controller and the fourth end of the isolation device respectively.

[0021] The output end of the voltage stabilizing chip is used for outputting the variable frequency control power supply.

[0022] In one of the embodiments, the power module further comprises a step-down circuit, and the step-down circuit comprises a step-down chip; the step-down chip is connected with the transformer circuit.

[0023] In one of the embodiments, the driving module comprises a first driving circuit, a second driving circuit and a third driving circuit, the first driving circuit, the second driving circuit and the third driving circuit have the same circuit structure and correspond to one of the three-phase windings of the direct-current motor respectively.

[0024] In one of the embodiments, the second common-mode inductor comprises three windings, the three windings are connected with the output terminals of the first driving circuit, the second driving circuit and the third driving circuit respectively.

[0025] In one of the embodiments, the first driving circuit comprises a first transistor, a second transistor, a first diode, a second diode, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor and a seventh resistor.

[0026] The first end of the first transistor is connected with a power supply, the second end of the first transistor is connected with one end of the first resistor, one end of the second resistor and one end of the third resistor respectively; the other end of the first resistor is connected with one end of the first diode, the other end of the first diode is connected with the other end of the second resistor;

[0027] The third end of the first transistor is connected with the other end of the third resistor and the first end of the second transistor respectively.

[0028] The second end of the second transistor is connected with one end of the fourth resistor, one end of the fifth resistor and one end of the sixth resistor respectively; the other end of the fourth resistor is connected with one end of the second diode, the other end of the second diode is connected with the other end of the fifth resistor.

[0029] The third end of the second transistor is the output terminal of the first driving circuit and is connected with the other end of the sixth resistor and one end of the seventh resistor, the other end of the seventh resistor is grounded.

[0030] In one of the embodiments, the driving module further comprises a driving control chip, the driving control chip comprises a plurality of control signal ports, the plurality of control signal ports correspond to the three-phase windings of the direct-current motor respectively.

[0031] The plurality of control signal ports are connected with the first driving circuit, the second driving circuit and the third driving circuit respectively.

[0032] The second technical problem is solved by the following technical scheme:

[0033] A range hood comprises the fan control system as described in any of the above. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0035] Figure 1 A structural schematic diagram of a fan control system of an embodiment of the present application;

[0036] Figure 2 A circuit schematic diagram of a power module in a fan control system of an embodiment of the present application;

[0037] Figure 3 A circuit schematic diagram of a voltage reduction circuit in a fan control system of an embodiment of the present application;

[0038] Figure 4 A connection schematic diagram of a second common mode inductor of a driving module in a fan control system of an embodiment of the present application;

[0039] Figure 5 A circuit schematic diagram of a first driving circuit in a fan control system of an embodiment of the present application.

[0040] Explanation of reference signs:

[0041] 1, power module; 11, filter circuit; 12, voltage conversion circuit; 121, rectifier circuit; 122, voltage conversion circuit; 13, variable frequency control power supply circuit; 2, driving module. Specific embodiments

[0042] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0043] The terms "first", "second" are only for description purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "multiple" is two or more.

[0044] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected, it can be mechanical connection, or electrical connection, it can be directly connected, or indirectly connected through an intermediate medium, it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0045] As described in the background, the current direct current range hood control system circuit is relatively complex, needs to have multiple sets of filter circuits, and artificial winding is formed in the motor to form a magnetic ring matched with it, resulting in higher manufacturing cost of the whole circuit.

[0046] Based on this, the utility model provides a fan control system, through first capacitor, second capacitor and first common mode inductor constitute filter circuit, connect first inductor and third capacitor after rectifier circuit further filter, guarantee filter effect at the same time simplify circuit, reduce cost, through connecting second common mode inductor between drive module and direct current motor, utilize second common mode inductor instead of magnetic ring on direct current motor line, reduce cost while filtering motor interference, and second common mode inductor is connected in circuit directly, compared with magnetic ring buckled on direct current motor line, reliability and stability are higher.

[0047] The embodiments of the utility model will be described below in combination with Figures 1 to 5 .

[0048] According to the embodiments of the utility model, on the one hand, a fan control system is provided. Figure 1 The structure diagram of the fan control system of the embodiments of the utility model is shown in Figure 1 , which comprises: a power module 1 and a drive module 2, and the power module 1 and the drive module 2 are connected. Among them, the power module 1 is used to provide power supply to the drive module 2; the drive module 2 is used to drive and control the direct current fan, and at the same time, the drive module 2 is connected with the direct current motor through the second common mode inductor Lcm2, the second common mode inductor Lcm2 can replace the magnetic ring on the direct current motor line for filtering motor interference, compared with buckling the magnetic ring on the direct current motor line, the second common mode inductor Lcm2 is directly connected in the circuit, which can reduce the labor cost and the device, and is not easy to appear loose, fall off and other situations, and has higher reliability and stability.

[0049] In the present embodiment, Figure 2 The circuit diagram of the power module in the fan control system of the embodiments of the utility model is shown in Figure 1 and 2As shown in the figure, the power module 1 includes a filter circuit 11 and a voltage conversion circuit 12; wherein the filter circuit 11 is used to filter the voltage accessed to the power module 1, improve the anti-interference ability of the circuit, and the voltage conversion circuit 12 is used to convert the voltage accessed to the power module 1 to obtain the required voltage.

[0050] In this embodiment, as shown in the figure, Figure 2 The filter circuit 11 includes a first capacitor C1, a second capacitor C2, and a first common mode inductor Lcm1, wherein the first common mode inductor Lcm1 is used to filter the differential mode interference and common mode interference in the circuit; the first end and the second end of the first common mode inductor Lcm1 are connected with the input power of the power module 1, and the third end and the fourth end of the first common mode inductor Lcm1 are connected with the voltage conversion circuit 12. The first capacitor C1 is connected between the first end and the second end of the first common mode inductor Lcm1, and the second capacitor C2 is connected between the third end and the fourth end of the first common mode inductor Lcm1; the first capacitor C1 and the second capacitor C2 are used as X capacitors to filter the hot line interference. The first capacitor C1, the second capacitor C2 and the first common mode inductor Lcm1 constitute a π-type filter circuit 11, which reduces the filtering devices in the circuit while ensuring the filtering effect.

[0051] In this embodiment, as shown in the figure, Figure 2 The voltage conversion circuit 12 includes a rectifier circuit 121, a first inductor L1, a third capacitor C3 and a transformer circuit 122. Wherein the input end of the rectifier circuit 121 is connected with the third end and the fourth end of the first common mode inductor Lcm1; the rectifier circuit 121 can adopt a rectifier bridge circuit or a rectifier chip, and the rectifier circuit 121 is used to rectify the alternating voltage input by the power module 1 and output a direct current voltage. One end of the first inductor L1 is connected with the output end of the rectifier circuit 121, and the other end of the first inductor L1 is connected with the transformer circuit 122. One end of the third capacitor C3 is connected with one end of the first inductor L1, and the other end of the third capacitor C3 is connected with the second capacitor C2 and grounded; the third capacitor C3 is used as a Y capacitor to suppress common mode interference.

[0052] In one embodiment, as shown in the figure, Figure 2As shown, the filter circuit 11 further comprises an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a fourth capacitor C4 and a fifth capacitor C5; the filter circuit 11 is connected to an alternating current power supply through a first interface CN1, and the first end and the second end of the first common mode inductor Lcm1 are connected to the first interface CN1. Among them, the eighth resistor R8 is a pressure sensitive resistor, which is connected between the live wire (ACL) and the neutral wire (ACN) to play a role of overvoltage protection. The ninth resistor R9 is a protection resistor, which is used to cut off the circuit when the current is too large, and plays a role of overload protection. One end of the tenth resistor R10 is connected to the live wire (ACL), the other end of the tenth resistor R10 is connected to one end of the eleventh resistor R11, and the other end of the eleventh resistor R11 is connected to the neutral wire (ACN), which plays a role of circuit short circuit protection. One end of the fourth capacitor C4 is connected to the third end of the first common mode inductor Lcm1, the other end of the fourth capacitor C4 is connected to one end of the fifth capacitor C5, and the other end of the fifth capacitor C5 is connected to the fourth end of the first common mode inductor Lcm1; at the same time, the other end of the fourth capacitor C4 and one end of the fifth capacitor C5 are connected to the ground through the plug-in part J1 together with the third capacitor C3.

[0053] In one embodiment, the fourth capacitor C4 and the fifth capacitor C5 are Y capacitors. By matching the parameters of the X capacitors, Y capacitors and the first common mode inductor Lcm1 in the filter circuit 11, the filtering effect of the filter circuit 11 is improved, so that the filtering effect can be guaranteed while using fewer filter devices and reducing the cost of devices.

[0054] In one embodiment, as shown in the figure, Figure 2 The power supply module 1 further comprises a variable frequency control power supply circuit 13 and a primary side feedback controller U2, which are respectively connected to the transformer circuit 122. Among them, the variable frequency control power supply circuit 13 is used to output a variable frequency control power supply to the driving module 2, so that the driving module 2 can drive and control the direct current motor; the primary side feedback controller U2 is used to monitor the state of the primary winding of the transformer in the transformer circuit 122, and at the same time realize circuit protection.

[0055] In one embodiment, as shown in the figure, Figure 2 The transformer circuit 122 comprises a transformer T1, and the transformer circuit 122, the variable frequency control power supply circuit 13 and the primary side feedback controller U2 share the transformer T1. Specifically, the transformer T1 comprises a first winding, a second winding and a third winding; the first winding and the second winding are located on the primary side of the transformer T1, which are primary windings; the third winding is located on the secondary side of the transformer T1, which is a secondary winding. Among them, the first winding is connected to the rectifier circuit 121, and the third winding is connected to the output end of the transformer circuit 122; the first end of the second winding is respectively connected to the power input port of the primary side feedback controller U2 and the variable frequency control power supply circuit 13, and the second end of the second winding is grounded.

[0056] In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2.

[0057] In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2. Figure 2 In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2.

[0058] Figure 2 In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2.

[0059] In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2. Figure 2 In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2.

[0060] Figure 2 In one embodiment, as shown in FIG. 1, the first end of the first winding is connected to the first output end of the rectifier circuit 121 through the first inductor L1, and the second output end of the rectifier circuit 121 is grounded through the third capacitor C3; the second end of the first winding is connected to the output end (SW port) of the primary side feedback controller U2.​​Figure 2 As shown, the variable frequency control power supply circuit 13 further comprises a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, and a tenth capacitor C10, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, and a sixteenth resistor R16, and a third transistor Q3.

[0061] In one embodiment, as shown in FIG. 2, the first resistor R1 is connected to the first end of the isolation device U1, and the second resistor R2 is connected to the second end of the isolation device U1. The first resistor R1 and the second resistor R2 serve to protect the isolation device U1 from overcurrent. Figure 2 As shown, the twelfth resistor R12 is connected to the first end of the isolation device U3, and serves to protect the isolation device U3 from overcurrent. One end of the thirteenth resistor R13 is connected to the fourth end of the isolation device U3, and the other end of the thirteenth resistor R13 is connected to the first end of the third transistor Q3 and the first end of the fourteenth resistor R14, and serves to protect the isolation device U3 from overcurrent and to match the load. The other end of the fourteenth resistor R14 is connected to the second end of the third transistor Q3 and the negative electrode of the third diode D3, and the third end of the third transistor is connected to the input end of the voltage stabilizing chip U4. The conduction timing of the third transistor Q3 is determined by the output of the isolation device U3 and the fourteenth resistor R14, and the voltage stabilizing chip U4 is controlled to work and output the variable frequency control power when the third transistor Q3 is turned on. One end of the fifteenth resistor R15 is connected to the second end of the third transistor Q3, and the other end of the fifteenth resistor R15 is connected to the third end of the third transistor Q3, and serves to protect the third transistor Q3 from short circuit.

[0062] In one embodiment, as shown in FIG. 2, the first resistor R1 is connected to the first end of the isolation device U1, and the second resistor R2 is connected to the second end of the isolation device U1. The first resistor R1 and the second resistor R2 serve to protect the isolation device U1 from overcurrent. Figure 2 As shown, one end of the sixth capacitor C6, one end of the seventh capacitor C7, and one end of the sixteenth resistor R16 are all connected to the negative electrode of the third diode D3 and the second end of the third transistor Q3, and the other end of the sixth capacitor C6, the other end of the seventh capacitor C7, and the other end of the sixteenth resistor R16 are all grounded, thereby serving to filter the voltage input to the third diode D3. One end of the eighth capacitor C8 is connected to the input end of the voltage stabilizing chip U4 and the third end of the third transistor Q3, and the other end of the eighth capacitor C8 is grounded, thereby serving to filter the voltage output from the third transistor Q3 to the voltage stabilizing chip U4. One end of the ninth capacitor C9 and one end of the tenth capacitor C10 are connected to the output end of the voltage stabilizing chip U4, and the other end of the ninth capacitor C9 and the other end of the tenth capacitor C10 are grounded, thereby serving to filter the variable frequency control voltage output by the voltage stabilizing chip U4.

[0063] In one embodiment, the third transistor Q3 can be a triode, the first end of the third transistor Q3 is the base of the triode, the second end of the third transistor Q3 is the emitter of the triode, and the third end of the third transistor Q3 is the collector of the triode. The sixth capacitor C6 and the ninth capacitor C9 can be electrolytic capacitors, and serve to stabilize the voltage and reduce noise.

[0064] In one embodiment, such as Figure 2 As shown, a seventeenth resistor R17 is connected between the power input port (VDD port) of the primary-side feedback controller U2 and the negative terminal of the fourth diode D4. The seventeenth resistor R17 serves as a current-limiting protection. The power input port of the primary-side feedback controller U2 is also connected to one end of the eleventh capacitor C11 and one end of the twelfth capacitor C12. The other ends of the eleventh capacitor C11 and the twelfth capacitor C12 are grounded to filter the voltage at the power input port. The feedback port (FB port) of the primary-side feedback controller U2 is connected to one end of the eighteenth resistor R18, one end of the nineteenth resistor R19, and one end of the thirteenth capacitor C13. The other end of the nineteenth resistor R19 is connected to one end of the twentieth resistor R20, and the other end of the twentieth resistor R20 is connected to the first end of the second winding. The other ends of the eighteenth resistor R18 and the thirteenth capacitor C13 are grounded. The feedback port (FB port) feeds voltage back to the second winding through the nineteenth resistor R19 and the twentieth resistor R20. The current detection port (CS port) of the primary-side feedback controller U2 is connected to one end of the twenty-first resistor R21, and the other end of the twenty-first resistor R21 is grounded.

[0065] In one embodiment, such as Figure 2 As shown, the transformer circuit 122 also includes a fifth diode D5, a twenty-second resistor R22 and a twenty-third resistor R23, and a fourteenth capacitor C14, a fifteenth capacitor C15, and a sixteenth capacitor C16. These components are connected between the first and second terminals of the third winding of transformer T1 to filter the voltage output from transformer T1. Specifically, the anode of the fifth diode D5 is connected to the first terminal of the third winding, and the cathode of the fifth diode D5 is connected to the output terminal of transformer circuit 122. The fifth diode D5 is used to perform half-wave rectification of transformer T1, outputting the voltage from the third winding in the same direction as its conduction. One end of the twenty-second resistor R22 is connected to the first terminal of the third winding, and the other end of the twenty-second resistor R22 is connected to one end of the fourteenth capacitor C14. The other end of the fourteenth capacitor C14 is connected to the output terminal of transformer circuit 122. One end of the 23rd resistor R23, one end of the 15th capacitor C15, and one end of the 16th capacitor C16 are connected to the output terminal of the voltage circuit, respectively. The other ends of the 23rd resistor R23, the 15th capacitor C15, and the 16th capacitor C16 are connected to the second terminal of the third winding and grounded.

[0066] In one embodiment, such as Figure 2 As shown, the seventeenth capacitor C17 and the eighteenth capacitor C18 are connected between the second end of the second winding and the second end of the third winding of transformer T1. The seventeenth capacitor C17 and the eighteenth capacitor C18 are Y capacitors.

[0067] In one embodiment, as shown in Figure 3 The voltage conversion circuit 12 further includes a nineteenth capacitor C19, a twentieth capacitor C20 and a twenty-first capacitor C21, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26 and a twenty-seventh resistor R27, and a sixth diode D6; the above-mentioned devices are connected between the rectifier circuit 121 and the first winding of the transformer T1, and filter the voltage output by the rectifier circuit 121 to the transformer T1. Among them, one end of the twenty-fourth resistor R24 is connected between the rectifier circuit 121 and the first inductor L1, and the other end of the twenty-fourth resistor R24 is connected with one end of the third capacitor C3. One end of the nineteenth capacitor C19 and one end of the twentieth capacitor C20 are connected between the first inductor L1 and the first end of the first winding, and the other end of the nineteenth capacitor C19 and the other end of the twentieth capacitor C20 are grounded. One end of the twenty-first capacitor C21, one end of the twenty-fifth resistor R25, and one end of the twenty-sixth resistor R26 are connected between the first inductor L1 and the first end of the first winding, and the other end of the twenty-first capacitor C21, the other end of the twenty-fifth resistor R25, and the other end of the twenty-sixth resistor R26 are connected with one end of the twenty-seventh resistor R27; the other end of the twenty-seventh resistor R27 is connected with the negative electrode of the sixth diode D6, and the negative electrode of the sixth diode D6 is respectively connected with the second end of the first winding and the output end (SW port) of the primary side feedback controller U2.

[0068] In one embodiment, the power supply module 1 further includes a step-down circuit for stepping down the voltage output by the voltage conversion circuit 122 to a fixed voltage value. Figure 3 The circuit schematic diagram of the step-down circuit in the fan control system of the embodiment of the utility model is shown in Figure 3 The step-down circuit includes a step-down chip U5, and the step-down chip U5 is connected with the voltage conversion circuit 122. Figure 4The voltage reduction circuit shown in the middle reduces the +12V voltage output by the voltage conversion circuit 122 to a +5V voltage. The voltage reduction circuit further includes a twenty-second capacitor C22, a twenty-third capacitor C23, and a twenty-fourth capacitor C24, a twenty-eighth resistor R28, and a second inductor L2. The one end of the twenty-second capacitor C22 is connected to the input port (VIN port) of the voltage reduction chip U5, and the other end of the twenty-second capacitor C22 is grounded, thereby filtering the voltage output by the voltage conversion circuit 122 to the voltage reduction chip U5. The one end of the second inductor L2 is connected to the switch port (SW port) of the voltage reduction chip U5, and the one end of the twenty-eighth resistor R28 is connected to the output port (VOUT port) of the voltage reduction chip U5. The other end of the second inductor L2 is connected to the other end of the twenty-eighth resistor R28, and is connected to the output end of the voltage reduction circuit. At the same time, the one end of the twenty-third capacitor C23 and the one end of the twenty-fourth capacitor C24 are connected to the other end of the second inductor L2 and the other end of the twenty-eighth resistor R28, and the other end of the twenty-third capacitor C23 and the other end of the twenty-fourth capacitor C24 are grounded. The twenty-eighth resistor R28, the twenty-third capacitor C23, and the twenty-fourth capacitor C24 constitute an RC filter current, which filters the voltage output by the voltage reduction chip U5.

[0069] In one embodiment, the drive module 2 includes a first drive circuit, a second drive circuit, and a third drive circuit, the first drive circuit, the second drive circuit, and the third drive circuit have the same circuit structure, and correspond to one of the three-phase windings of the DC motor respectively. For example, the first drive circuit corresponds to the W-phase winding of the DC motor, the second drive circuit corresponds to the V-phase winding of the DC motor, and the third drive circuit corresponds to the U-phase winding of the DC motor.

[0070] In one embodiment, the drive module 2 further includes a drive control chip, the drive control chip includes a plurality of control signal ports, the plurality of control signal ports correspond to the three-phase windings of the DC motor respectively, and the plurality of control signal ports are connected to the first drive circuit, the second drive circuit, and the third drive circuit respectively.

[0071] In one embodiment, for each winding of the direct current motor, that is, for each drive circuit, the drive control chip corresponds to the following control signal ports: a lower bridge PWM output port, an upper bridge PWM output port, an upper bridge bootstrap ground terminal reference port, and an upper bridge bootstrap power supply port. Specifically, for the W-phase winding, the drive control chip includes the following control signal ports: a W-phase lower bridge PWM output port (LW port), a W-phase upper bridge PWM output port (HW port), a W-phase upper bridge bootstrap ground terminal reference port (VSW port), and a W-phase upper bridge bootstrap power supply port (VBW port); for the V-phase winding, the drive control chip includes the following control signal ports: a V-phase lower bridge PVM output port (LV port), a V-phase upper bridge PVM output port (HV port), a V-phase upper bridge bootstrap ground terminal reference port (VSV port), and a V-phase upper bridge bootstrap power supply port (VBV port); and for the U-phase winding, the drive control chip includes the following control signal ports: a U-phase lower bridge PUM output port (LU port), a U-phase upper bridge PUM output port (HU port), a U-phase upper bridge bootstrap ground terminal reference port (VSU port), and a U-phase upper bridge bootstrap power supply port (VBU port).

[0072] In one embodiment, the circuit structure of each drive circuit in the embodiment is further described below by taking the first drive circuit as an example. Figure 4 The circuit schematic diagram of the first drive circuit in the fan control system of the embodiment is shown in FIG. 1. Figure 4 As shown in FIG. 1, the first drive circuit includes a first transistor Q1, a second transistor Q2, a first diode D1, a second diode D2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a seventh resistor R7.

[0073] In one embodiment, as shown in FIG. 1, the first drive circuit includes the first transistor Q1, the second transistor Q2, the first diode D1, the second diode D2, the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, and the seventh resistor R7. Figure 4As shown, the first end of the first transistor Q1 is connected with a power supply, the second end of the first transistor Q1 is connected with one end of the first resistor R1, one end of the second resistor R2 and one end of the third resistor R3 respectively; the other end of the first resistor R1 is connected with one end of the first diode D1, the other end of the first diode D1 is connected with the other end of the second resistor R2. The third end of the first transistor Q1 is connected with the other end of the third resistor R3 and the first end of the second transistor Q2 respectively. The second end of the second transistor Q2 is connected with one end of the fourth resistor R4, one end of the fifth resistor R5 and one end of the sixth resistor R6 respectively; the other end of the fourth resistor R4 is connected with one end of the second diode D2, the other end of the second diode D2 is connected with the other end of the fifth resistor R5. The third end of the second transistor Q2 is the output end of the first driving circuit, and is connected with the other end of the sixth resistor R6 and one end of the seventh resistor R7, the other end of the seventh resistor R7 is grounded. The winding of the corresponding DC motor is connected between the third end of the first transistor Q1 and the first end of the second transistor Q2.

[0074] In one embodiment, as shown in the figure, Figure 5 the first driving circuit is the driving circuit corresponding to the W-phase winding. Correspondingly, one end of the first diode D1 is also connected with the W-phase upper bridge PWM output port (HW port) of the driving control chip, and the W-phase upper bridge PWM signal is inputted, so that the first transistor Q1 is controlled to be turned on or turned off through the W-phase upper bridge PWM signal; one end of the second diode D2 is also connected with the W-phase lower bridge PWM output port (LW port), and the W-phase lower bridge PWM signal is inputted, so that the second transistor Q2 is controlled to be turned on or turned off through the W-phase lower bridge PWM signal; the third end of the first transistor Q1 and the first end of the second transistor Q2 are connected with the W-phase upper bridge bootstrap ground reference port (VSW port), so that the driving control chip takes the point between the third end of the first transistor Q1 and the first end of the second transistor Q2 as the reference ground of the W-phase upper bridge bootstrap.

[0075] In one embodiment, the first transistor Q1 and the second transistor Q2 can be insulated gate bipolar transistors. The first end of the first transistor Q1 and the first end of the second transistor Q2 correspond to the collector of the insulated gate bipolar transistor, the second end of the first transistor Q1 and the second end of the second transistor Q2 correspond to the gate of the insulated gate bipolar transistor, and the third end of the first transistor Q1 and the third end of the second transistor Q2 correspond to the emitter of the insulated gate bipolar transistor.

[0076] In one embodiment, Figure 5 the second common-mode inductor of the driving module in the fan control system is connected, as shown in the figure, Figure 5As shown, the second interface CN2 is connected with the DC motor, and the interfaces corresponding to the three phases of the DC motor on the second interface CN2 are respectively connected with the second common-mode inductor Lcm2. The second common-mode inductor Lcm2 includes three windings, which are respectively connected with the three-phase pins of the DC motor; the three windings are respectively connected with the output terminals of the first driving circuit, the second driving circuit and the third driving circuit; specifically, the three windings are respectively connected with the output terminals of the first driving circuit, the second driving circuit and the third driving circuit through the corresponding interfaces on the second interface CN2.

[0077] In one embodiment, as shown in Figure 5 As shown, the first winding of the second common-mode inductor Lcm2 corresponds to the U phase of the DC motor, the second winding of the second common-mode inductor Lcm2 corresponds to the V phase of the DC motor, and the third winding of the second common-mode inductor Lcm2 corresponds to the W phase of the DC motor. One end of the first winding of the second common-mode inductor Lcm2 is connected with the corresponding driving circuit through the second interface CN2, and the other end of the first winding of the second common-mode inductor Lcm2 is respectively connected with one end of the twenty-fifth capacitor C25 and one end of the twenty-sixth capacitor C26. The other end of the twenty-fifth capacitor C25 is connected with the negative electrode of the seventh diode D7, the positive electrode of the seventh diode D7 is connected with one end of the twenty-ninth resistor R29, and the other end of the twenty-ninth resistor R29 is connected with the power supply, so that the point at the negative electrode of the seventh diode D7 can be used as the upper bridge bootstrap power supply of the corresponding phase, that is, the U phase upper bridge bootstrap power supply. The other end of the twenty-sixth capacitor C26 is grounded, so that the potential at the other end of the first winding of the second common-mode inductor Lcm2 can be used as the upper bridge bootstrap reference ground of the corresponding phase, that is, the U phase upper bridge bootstrap reference ground.

[0078] In one embodiment, as shown in Figure 5 As shown, one end of the second winding of the second common-mode inductor Lcm2 is connected with the corresponding driving circuit through the second interface CN2, and the other end of the second winding of the second common-mode inductor Lcm2 is respectively connected with one end of the twenty-seventh capacitor C27 and one end of the twenty-eighth capacitor C28. The other end of the twenty-seventh capacitor C27 is connected with the negative electrode of the eighth diode D8, and the positive electrode of the eighth diode D8 is connected with one end of the twenty-ninth resistor R29, so that the point at the negative electrode of the eighth diode D8 can be used as the upper bridge bootstrap power supply of the corresponding phase, that is, the V phase upper bridge bootstrap power supply. The other end of the twenty-eighth capacitor C28 is grounded, so that the potential at the other end of the second winding of the second common-mode inductor Lcm2 can be used as the upper bridge bootstrap reference ground of the corresponding phase, that is, the V phase upper bridge bootstrap reference ground.

[0079] In one embodiment, as shown in Figure 5As shown, one end of the third winding of the second common mode inductor Lcm2 is connected with the corresponding driving circuit through the second interface CN2, and the other end of the third winding of the second common mode inductor Lcm2 is connected with one end of the twenty-ninth capacitor C29 and one end of the thirtieth capacitor C30 respectively. The other end of the twenty-ninth capacitor C29 is connected with the negative electrode of the ninth diode D9, and the positive electrode of the ninth diode D9 is connected with one end of the twenty-ninth resistor R29, so that the point at the negative electrode of the eighth diode D8 can be used as the upper bridge bootstrap power supply of the corresponding phase, that is, the W-phase upper bridge bootstrap power supply. The other end of the thirtieth capacitor C30 is grounded, so that the potential at the other end of the third winding of the second common mode inductor Lcm2 can be used as the upper bridge bootstrap reference ground of the corresponding phase, that is, the W-phase upper bridge bootstrap reference ground.

[0080] In one embodiment, as shown in the specific embodiments, ​ As shown, the other end of the twenty-ninth resistor R29 is also connected with one end of the thirty-first capacitor C31, and the other end of the thirty-first capacitor C31 is grounded, and the thirty-first capacitor C31 is used for filtering the power input to the twenty-ninth resistor R29.

[0081] In one embodiment, the above specific embodiments only explain the necessary circuit structure of the fan control system, and the fan control system can further include more circuit structures, for example, can include more voltage reduction circuits and voltage stabilizing circuits to provide more sizes of power supply for the fan control system.

[0082] The fan control system provided by the utility model has the advantages that the first capacitor, the second capacitor and the first common mode inductor constitute a filter circuit, the first inductor and the third capacitor connected after the rectifier circuit are used for further filtering, the circuit is simplified and the cost is reduced while the filtering effect is ensured, the second common mode inductor is connected between the driving module and the DC motor, the second common mode inductor is used to replace the magnetic ring on the DC motor wire, the cost is reduced while the motor interference is filtered out, and the second common mode inductor is directly connected in the circuit, so that the reliability and stability are higher than those of the magnetic ring buckled on the DC motor wire.

[0083] According to the embodiments of the utility model, on the other hand, a kind of range hood is also provided, comprising the fan control system described in any one of the above embodiments.

[0084] In the specific content of the above specific embodiments, any inconsistent combination of technical features can be combined, to make the description simple, not all possible combinations of the above technical features are described, however, as long as the combination of these technical features does not exist contradiction, it should be considered that it is within the scope of the present application.

[0085] The specific contents of the foregoing specific embodiments are only to express several embodiments of the utility model, and the description is more specific and detailed, but it cannot be understood as the limitation of the utility model patent scope. It should be pointed out that for ordinary skilled person in the art, without departing from the concept of the utility model, a number of modifications and improvements can be made, which belong to the protection scope of the utility model.

Claims

1. A fan control system, characterized by, The system comprises a power module (1) and a driving module (2), the power module (1) and the driving module (2) are connected; the power module (1) comprises a filter circuit (11) and a voltage conversion circuit (12); The filter circuit (11) comprises a first capacitor C1, a second capacitor C2 and a first common-mode inductor Lcm1; the first end and the second end of the first common-mode inductor Lcm1 are connected with the input power of the power module (1), the third end and the fourth end of the first common-mode inductor Lcm1 are connected with the voltage conversion circuit (12); the first capacitor C1 is connected between the first end and the second end of the first common-mode inductor Lcm1, and the second capacitor C2 is connected between the third end and the fourth end of the first common-mode inductor Lcm1; The voltage conversion circuit (12) comprises a rectifier circuit (121), a first inductor L1, a third capacitor C3 and a transformer circuit (122); the input end of the rectifier circuit (121) is connected with the third end and the fourth end of the first common-mode inductor Lcm1; one end of the first inductor L1 is connected with the output end of the rectifier circuit (121), and the other end of the first inductor L1 is connected with the transformer circuit (122); one end of the third capacitor C3 is connected with one end of the first inductor L1, and the other end of the third capacitor C3 is connected with the second capacitor C2 and grounded; The driving module (2) is connected with a direct current motor through a second common-mode inductor Lcm2.

2. The system of claim 1, wherein, The power module (1) further comprises a variable frequency control power supply circuit (13) and a primary side feedback controller U2; The transformer circuit (122) comprises a transformer T1, the transformer T1 comprises a first winding, a second winding and a third winding; the first winding and the second winding are located on the primary side of the transformer T1, and the third winding is located on the secondary side of the transformer T1; The first winding is connected with the rectifier circuit (121); the third winding is connected with the output end of the transformer circuit (122); The first end of the second winding is connected with the power input port of the primary side feedback controller U2 and the variable frequency control power supply circuit (13) respectively, and the second end of the second winding is grounded.

3. The system of claim 2, wherein, The first end of the first winding is connected with the first output end of the rectifier circuit (121) through the first inductor L1, and the second output end of the rectifier circuit (121) is grounded through the third capacitor C3; The second end of the first winding is connected with the output end of the primary side feedback controller U2.

4. The system of claim 2, wherein, The variable frequency control power supply circuit (13) comprises an isolation device U3 and a voltage stabilizing chip U4; The first end of the isolation device U3 is connected with a variable frequency control signal, and the second end and the third end of the isolation device U3 are grounded respectively; The input end of the voltage stabilizing chip U4 is connected with the first end of the second winding, the power input port of the primary side feedback controller U2 and the fourth end of the isolation device U3 respectively; The output end of the voltage stabilizing chip U4 is used for outputting a variable frequency control power supply.

5. The system of claim 1, wherein, The power module (1) further comprises a step-down circuit, wherein the step-down circuit comprises a step-down chip U5; and the step-down chip U5 is connected with the transformer circuit (122).

6. The system of claim 1, wherein, The driving module (2) comprises a first driving circuit, a second driving circuit and a third driving circuit, wherein the first driving circuit, the second driving circuit and the third driving circuit have the same circuit structure and correspond to one of the three-phase windings of the DC motor respectively.

7. The system of claim 6, wherein, The second common-mode inductor Lcm2 comprises three windings, wherein the three windings are connected with the output terminals of the first driving circuit, the second driving circuit and the third driving circuit respectively.

8. The system of claim 6, wherein, The first driving circuit comprises a first transistor Q1, a second transistor Q2, a first diode D1, a second diode D2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7. The first end of the first transistor Q1 is connected with a power supply, and the second end of the first transistor Q1 is connected with one end of the first resistor R1, one end of the second resistor R2 and one end of the third resistor R3 respectively; the other end of the first resistor R1 is connected with one end of the first diode D1, and the other end of the first diode D1 is connected with the other end of the second resistor R2; The third end of the first transistor Q1 is connected with the other end of the third resistor R3 and the first end of the second transistor Q2 respectively. The second end of the second transistor Q2 is connected with one end of the fourth resistor R4, one end of the fifth resistor R5 and one end of the sixth resistor R6 respectively; the other end of the fourth resistor R4 is connected with one end of the second diode D2, and the other end of the second diode D2 is connected with the other end of the fifth resistor R5; The third end of the second transistor Q2 is the output terminal of the first driving circuit and is connected with the other end of the sixth resistor R6 and one end of the seventh resistor R7, and the other end of the seventh resistor R7 is grounded.

9. The system of claim 6, wherein, The driving module (2) further comprises a driving control chip, wherein the driving control chip comprises a plurality of control signal ports, and the plurality of control signal ports correspond to the three-phase windings of the DC motor respectively. The plurality of control signal ports are connected with the first driving circuit, the second driving circuit and the third driving circuit respectively.

10. A range hood, characterized by The fan control system comprises the fan control system according to any one of claims 1-9.

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