Fan control circuit, power unit, charging equipment and energy storage system

Abstract

The utility model discloses a fan control circuit, a power unit, charging equipment and an energy storage system, and belongs to the technical field of electronic circuits. The fan control circuit comprises a fan, an interference source and a voltage division module, the interference source is connected with the fan in parallel and is used for providing an interference signal for the fan; and the voltage dividing module is respectively connected with the fan and the interference source in parallel and is used for reducing an interference signal applied to the fan by the interference source. By introducing the voltage dividing module, interference signals applied to the two ends of the fan by an interference source are reduced, the problems that the voltage at the two ends of the fan exceeds the fan bearing range and the fan is prone to failure due to the existence of the interference source are effectively solved, and the anti-interference capacity of the fan is improved.

Description

Technical Field

[0001] The present application belongs to the field of electronic circuit technology, and in particular relates to a fan control circuit, a power unit, a charging device, and an energy storage system. Background Art

[0002] For equipment (such as power units) that use direct ventilation to exchange heat with external cold air, although the temperature in the cavity can be quickly controlled, water vapor, foreign matter, etc. can easily enter the shell, increasing the risk of equipment failure and having a certain impact on the reliability of the equipment.

[0003] Although the power unit with IP65 protection level avoids the disadvantages of direct ventilation to a certain extent, the completely sealed casing will cause the local temperature inside the cavity to rise rapidly, and direct heat exchange cannot be performed, causing the power unit to enter the power derating state prematurely. To solve this problem, a spoiler fan is added inside the power unit. The spoiler fan balances the internal temperature and solves the problem of entering the derating state prematurely due to the rapid temperature rise of local components.

[0004] The spoiler fan used is limited by the volume of the power unit, and the range of options is very small. It must meet both the speed requirements and the air volume requirements. Therefore, at the beginning of the design, the anti-interference ability was sacrificed. Although the Vienna circuit used has a simple structure, its characteristics are large midpoint fluctuations and large common-mode interference, so the fan is prone to failure. Utility Model Content

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a fan control circuit, a power unit, a charging device and an energy storage system, which reduce the interference signal applied by the interference source to both ends of the fan by introducing a voltage divider module, thereby improving the fan's anti-interference ability.

[0006] In a first aspect, the present application provides a fan control circuit, the circuit comprising:

[0007] The interference source is connected in parallel with the fan and is used to provide an interference signal to the fan;

[0008] The voltage divider module is connected in parallel with the fan and the interference source, respectively, and is used to reduce the interference signal applied to the fan by the interference source.

[0009] According to the fan control circuit of the present application, by introducing a voltage divider module, the interference signal applied to the two ends of the fan by the interference source is reduced, and the problem of the fan being prone to failure due to the voltage at both ends of the fan exceeding the fan's tolerance range caused by the existence of the interference source is effectively suppressed, thereby improving the fan's anti-interference ability.

[0010] According to an embodiment of the present application, it further includes: an optical coupling module, wherein the optical coupling module is electrically connected to the fan and the interference source respectively.

[0011] According to the fan control circuit of the present application, due to the existence of the interference source, the interference loop formed by the parasitic capacitance inside the fan and the safety capacitance of the optical coupling module will directly apply the interference source to both ends of the fan, causing the switch tube inside the fan to fail. The present application introduces a voltage divider module and destroys the interference loop to reduce the interference signal applied by the interference source to both ends of the fan, thereby improving the fan's anti-interference ability and solving the problem of the fan's easy failure.

[0012] According to an embodiment of the present application, the optical coupling module includes: a light emitting device and a photosensitive device, wherein the light emitting device is electrically connected to the fan, and the photosensitive device is electrically connected to the interference source.

[0013] According to an embodiment of the present application, the voltage divider module includes: one or more capacitors, and the multiple capacitors are connected in parallel.

[0014] According to the fan control circuit of the present application, one or more capacitors are introduced and connected in parallel with the parasitic capacitance of the fan. Due to the addition of the parallel capacitors, the capacity after parallel connection is increased and the total voltage after parallel connection is reduced. Then, the voltage across the parallel parasitic capacitance and the introduced one or more capacitors can effectively suppress interference sources and improve the fan's anti-interference ability.

[0015] According to an embodiment of the present application, the capacitor is a ceramic capacitor or an electrolytic capacitor.

[0016] According to an embodiment of the present application, the interference source is generated by a Vienna circuit or a power supply module.

[0017] According to an embodiment of the present application, it further includes: a safety capacitor, wherein the safety capacitor is connected in series with the voltage divider module.

[0018] According to the fan control circuit of the present application, by introducing a safety capacitor, it is ensured that no electric shock will occur in the event of a capacitor failure, thereby protecting personal safety.

[0019] In a second aspect, the present application provides a power unit, which includes the fan control circuit as described in the first aspect.

[0020] In a third aspect, the present application provides a charging device, which includes a power unit as described in the second aspect above.

[0021] In a fourth aspect, the present application provides an energy storage system, which includes the power unit as described in the second aspect.

[0022] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0024] Figure 1 It is one of the structural schematic diagrams of the fan control circuit provided in the embodiment of the present application;

[0025] Figure 2 It is a structural diagram of a feedback pin circuit application solution provided in an embodiment of the present application;

[0026] Figure 3 This is the second structural schematic diagram of the fan control circuit provided in the embodiment of the present application;

[0027] Figure 4 is a schematic diagram of the structure of an equivalent circuit provided in an embodiment of the present application;

[0028] Figure 5 It is one of the schematic diagrams of the feedback pin voltage stress provided in the embodiment of the present application;

[0029] Figure 6 This is the second schematic diagram of the feedback pin voltage stress provided in the embodiment of the present application;

[0030] Figure 7 is a schematic diagram of the structure of a power unit provided in an embodiment of the present application;

[0031] Figure 8 is a schematic diagram of the structure of a charging device provided in an embodiment of the present application;

[0032] Fig. 9 It is a schematic diagram of the structure of the energy storage system provided in the embodiment of the present application.

[0033] Figure numerals: 100: fan control circuit, 110: interference source; 120: fan; 130: voltage divider module; 200: power unit, 300: charging device, 400: energy storage system. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0035] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0036] The fan control circuit, power unit, charging device and energy storage system provided in the embodiments of the present application are described in detail below with reference to the accompanying drawings through specific embodiments and their application scenarios.

[0037] like Figure 1 As shown, the fan control circuit 100 may specifically include: an interference source 110 , a fan 120 and a voltage division module 130 .

[0038] Due to the existence of interference sources and the inability to avoid them, the only way to effectively solve the problem of fan failure is to analyze the interference path of the interference source and try to solve it by destroying the interference path. However, the fact is that the power unit is a closed space, and the clues for analyzing the interference path are relatively messy. It can be transmitted through PCB circuit boards, cables, or even space radiation. Therefore, this application improves the fan's anti-interference ability by destroying the interference path and adding a filtering strategy (i.e., a voltage divider module) to solve the problem of fan failure.

[0039] like Figure 2 As shown in the figure, the Vds power supply requirement is a maximum of 26.4V, otherwise there is a risk of breakdown inside the fan (DC FAN). Due to the interference of common-mode voltage, there is a voltage of more than 32V on the measured Vds. Especially in harsh working conditions, the voltage may be higher, causing the internal control components of the fan to be subjected to greater voltage stress. As the working time accumulates, the reliability of the fan gradually decreases, eventually leading to fan failure.

[0040] This application analyzes the failure mechanism of the device from aspects such as the power supply circuit, parasitic parameters and interference sources, and proposes solutions based on the mechanism analysis to achieve the purpose of improving the anti-interference ability of the fan.

[0041] Specifically, the fan control circuit 100 may include an interference source 110, a fan 120, and a voltage divider module 130. The fan 120 is connected in parallel with the interference source 110, and the voltage divider module 130 is connected in parallel with both the interference source 110 and the fan 120. The interference source 110 may be specifically used to provide an interference signal to the fan 120, and the voltage divider module 130 is configured to reduce the interference signal applied by the interference source 110 to both ends of the fan 120, and the interference signal may be a voltage signal.

[0042] The fan control circuit provided in the embodiment of the present application reduces the interference signal applied to the two ends of the fan by the interference source by introducing a voltage divider module, effectively suppresses the problem that the voltage at the two ends of the fan exceeds the fan's tolerance range due to the existence of the interference source, which makes the fan prone to failure, and improves the fan's anti-interference ability.

[0043] In some embodiments, the fan control circuit 100 may further include:

[0044] The optical coupling module U1 is electrically connected to the fan 120 and the interference source 110 respectively.

[0045] like Figure 3 As shown, the fan control circuit further includes an optical coupling module U1, which is electrically connected to the fan 120 and the interference source 110. Figure 3 At the beginning of the design, in order to suppress the interference source 110, a safety capacitor C6 connected to the optical coupling module U1 was introduced.

[0046] In some embodiments, the optical coupling module U1 may specifically include: a light emitting device and a photosensitive device, wherein the light emitting device is electrically connected to the fan, and the photosensitive device is electrically connected to the interference source.

[0047] Specifically, the optical coupling device U1 may include a light emitting device and a photosensitive device, wherein the light emitting device may be a light emitting diode, and the photosensitive device may be a photosensitive transistor. The light emitting device is electrically connected to the fan 120, as shown in FIG. Figure 3 As shown, the photosensitive transistor is electrically connected to the interference source 110, as shown in FIG. Figure 3 shown.

[0048] In some embodiments, the voltage dividing module 130 may specifically include: one or more capacitors, and the multiple capacitors are connected in parallel.

[0049] Specifically, the voltage divider module 130 can be implemented by using a capacitor or multiple capacitors connected in parallel. The example diagram of introducing a capacitor C5 as the voltage divider module 130 can refer to Figure 3 .

[0050] The purpose of further reducing the voltage applied by the interference source 110 to both ends of C4 can be achieved by increasing the capacitance value of C5. For example, a capacitor with a larger capacitance value can be used to replace C5. The purpose of further reducing the voltage applied by the interference source 110 to both ends of C4 can also be achieved by adding a new capacitor based on C5 and connecting it in parallel with C5. This application does not make specific restrictions on this.

[0051] In some embodiments, the fan control circuit may further include: a safety capacitor C3 , wherein the safety capacitor C3 is connected in series with the voltage dividing module 130 .

[0052] like Figure 3 As shown, U1 is an optocoupler and V1 is Figure 2 The rotation signal output shown can be used as the input power supply of the optocoupler U1. C4 is Figure 2 The equivalent capacitance of the switch tube inside the fan 120 shown, C1 and C2 are the equivalent capacitance of the optocoupler. In the actual circuit structure, C1 and C2 have no entity. C7 is the equivalent capacitance of the fan 120 output rectifier diode to the housing. In the actual circuit structure, C7 also has no entity. C6 is the safety capacitor of the primary and secondary sides of the optocoupler U1, and V2 is the interference source 110.

[0053] The working principle of the circuit is as follows: if there is no V2, V1 supplies power to the optical coupler U1, and the maximum voltage of V1 is 24V (this voltage is the rated working voltage of the fan 120). The speed of the fan 120 is controlled by the pulse width modulation (PWM) signal sent by the digital signal processing (DSP). Different control frequencies correspond to different speeds. When the speed reaches 100%, the control frequency is 290Hz, and when the speed is 0, the control frequency is 0Hz. The voltage across C4 is always 24V. No matter how high the speed is, the voltage amplitude across C4 is always 24V, and the voltage stress is within the tolerance range of the internal components of the fan 120. Due to the existence of the V2 interference source 110, an interference loop is formed through the parasitic capacitors C1, C2, C4, C7 and C6 inside the device, and the interference signal generated by the interference source 110, such as the voltage signal, is superimposed on the two ends of C4, causing the voltage across C4 to exceed the tolerance range, and the switch tube inside the fan 120 fails, so that the host computer cannot identify the fan speed.

[0054] To solve the above problems, the specific implementation plan is as follows: Figure 4As shown, the interference source 110 has two interference paths, both of which can realize loops. One interference loop is formed by the interference source 110 through C6, C7 and C3 through the housing, and the other loop is formed by V2 through C1, C2 and C4 through the housing. As long as these two interference loops are disconnected, the purpose of disconnecting the interference path can be achieved. For the first loop, C7 is the parasitic capacitance of the rectifier diode on the output side of the fan 120 to the housing. It has no entity and cannot be removed, so disconnecting this path has no effect on improving the circuit. C3 is the safety capacitor of V1, and its function is to improve electromagnetic interference (EMI), and it is in parallel with C7. C6 is the safety capacitor of the primary and secondary sides of the optocoupler U1, and it also plays a role in EMI suppression. Therefore, this loop can only be disconnected by removing C6. However, removing the interference loop sometimes cannot completely improve the voltage stress of the spoiler fan feedback pin. The second loop is composed of C1, C2 and C4, of which C1 and C2 are parasitic capacitors of the optocoupler U1. Similarly, since they have no entity, they cannot be removed. C4 is the parasitic capacitor inside the spoiler fan 120 and cannot be removed. This loop cannot be solved by disconnecting the circuit, so the voltage across the equivalent capacitor C4 applied by the interference source 110 to the fan 120 is reduced by adding a voltage divider module 130. In this application, capacitor C5 is used as the voltage divider module 130. The parallel capacity of C2, C4 and C5 is increased, which is defined as C8. C7 and C3 are connected in parallel, which is defined as C9. The original circuit is equivalent to C1, C8 and C9 connected in series and then in parallel with the interference source V2. Specifically, Figure 4 As shown in the figure, due to the addition of C5, the capacity of C8 increases, which reduces the voltage stress across C4.

[0055] As shown in the formula:

[0056] C 8 =C 2 +C 4 +C 5

[0057] C 9 =C 3 +C 7

[0058]

[0059] Among them, C 2 Represents the capacitance value of capacitor C2, C 4 Represents the capacitance value of capacitor C4, C 5 Represents the capacitance value of capacitor C5, C 8 Represents the total capacitance of C2, C4 and C5 in parallel, C 3 Represents the capacitance value of capacitor C3, C 7 represents the capacitance value of C7, C9 Represents the total capacitance of C3 and C7 in parallel, V c8 represents the voltage across C8, which is equal in value to the voltage across C4, and ω represents the angular frequency.

[0060] From the formula, it can be concluded that the increase in the capacity of C8 reduces the voltage amplitude at both ends of C8, which is equivalent to reducing the voltage stress at both ends of C4, thereby ensuring that the voltage stress of the internal components of the spoiler fan is within an acceptable range. At the same time, C6 is disconnected, destroying one of the interference paths. The feedback pin voltage (i.e., the voltage at both ends of C4) stress after the fan control circuit provided in the embodiment of the present application is specifically as follows: Figure 5 and Figure 6 As shown, Figure 5 The voltage stress across C4 is when the capacitor C5 is not added and the interference loop is not disconnected. Figure 6 The fan control circuit provided in the embodiment of the present application is used, and the voltage stress at both ends of C4 is. Figure 5 and Figure 6 It can be seen that the use of the fan control circuit of the present application ultimately improves the anti-interference ability of the fan and solves the problem of the fan being prone to failure.

[0061] It should be noted that the fan control circuit provided in the embodiment of the present application is simple and feasible. Applying it to a power unit can improve the anti-interference capability of the spoiler fan of the power unit and increase the reliability of the power unit.

[0062] By applying it to charging equipment such as charging piles, the above functions can be achieved regardless of the manufacturer and model of the charging pile power unit.

[0063] In some embodiments, the capacitor is a ceramic capacitor or an electrolytic capacitor.

[0064] Specifically, the capacitor C5 can be a ceramic capacitor or an electrolytic capacitor, which is not specifically limited in the present application.

[0065] According to the fan control circuit provided in the embodiment of the present application, due to the existence of the interference source, the interference loop formed by the parasitic capacitance inside the fan and the safety capacitance of the optical coupling module will directly apply the interference source to both ends of the fan, causing the switch tube inside the fan to fail. The present application introduces a voltage divider module and destroys the interference loop to reduce the interference signal applied by the interference source to both ends of the fan, thereby improving the fan's anti-interference ability and solving the problem of the fan's easy failure.

[0066] In some embodiments, the interference source is generated by a Vienna circuit or a power supply module.

[0067] Specifically, the interference source 110 in the present application may be generated by a Vienna circuit or a power supply module.

[0068] According to the fan control circuit provided in the embodiment of the present application, by introducing a safety capacitor, it is ensured that no electric shock will occur in the event of a capacitor failure, thereby protecting personal safety.

[0069] The embodiment of the present application also provides a power unit 200 .

[0070] like Figure 7 As shown, the power unit 200 includes: a fan control circuit 100 .

[0071] Specifically, the fan control circuit 100 provided in the embodiment of the present application can be specifically applied to a power unit 200, such as a 30KW power unit. The 30KW power unit adopts a two-stage circuit topology, the front stage is an AC / DC circuit, and the rear stage is a DC / DC circuit, wherein the AC / DC circuit adopts a Vienna topology circuit, and the rear stage is a DC / DC circuit adopts an LLC topology.

[0072] The embodiment of the present application also provides a charging device 300 .

[0073] like Figure 8 As shown, the charging device 300 includes a power unit 200 .

[0074] Specifically, the charging device 300 can be a new energy charging device, such as a charging pile. By applying the above-mentioned power unit 20 to the charging pile, the charging efficiency is high, the volume is small, the structure is simple and reliable, and the manufacturability is high.

[0075] The embodiment of the present application also provides an energy storage system 400 .

[0076] like Fig. 9 As shown, the energy storage system 400 includes a power unit 200 .

[0077] Specifically, the power unit 200 provided in the embodiment of the present application can also be applied to an energy storage system 400, such as a photovoltaic power generation energy storage system, a wind power generation energy storage system, etc.

[0078] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0079] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", 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 application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0080] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A fan control circuit, characterized in that: include: A fan, an interference source and a voltage divider module; the interference source is connected in parallel with the fan to provide an interference signal for the fan; The voltage divider module is connected in parallel with the fan and the interference source, respectively, and is used to reduce the interference signal applied to the fan by the interference source.

2. The fan control circuit according to claim 1, characterized in that: Also includes: An optical coupling module is electrically connected to the fan and the interference source respectively.

3. The fan control circuit according to claim 2, characterized in that: The optical coupling module includes: a light emitting device and a photosensitive device, wherein the light emitting device is electrically connected to the fan, and the photosensitive device is electrically connected to the interference source.

4. The fan control circuit according to claim 1, characterized in that: The voltage dividing module includes: one or more capacitors, and the multiple capacitors are connected in parallel.

5. The fan control circuit according to claim 4, characterized in that: The capacitor is a ceramic capacitor or an electrolytic capacitor.

6. The fan control circuit according to claim 1, characterized in that: The interference source is generated by a Vienna circuit or a power supply module.

7. The fan control circuit according to any one of claims 1 to 6, characterized in that: Also includes: A safety capacitor is connected in series with the voltage divider module.

8. A power unit, characterized in that: The invention comprises a fan control circuit as described in any one of claims 1 to 7.

9. A charging device, characterized in that: Comprising the power unit as claimed in claim 8.

10. An energy storage system, characterized in that: Comprising the power unit as claimed in claim 8.

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