Bidirectional DC / DC converter

Abstract

The invention relates to a bidirectional DC / DC converter. The invention relates to the technical field of power electronic application. The converter comprises a converter shell, a cover is detachably installed on the front side of the converter shell, a first heat dissipation hole and a second heat dissipation hole are formed in the two sides of the converter shell respectively, a fan blade mechanism for dissipating heat of elements installed in the converter shell is arranged in the converter shell, and the fan blade mechanism comprises a power shaft and fan blades. Due to the fact that the gap is reserved between the first magnet and the second magnet, the fan blades are driven to rotate in a magnetic attraction mode, noise can be reduced, the noise is low and even silent, and use is not affected. The rubber pad has a certain elastic buffering effect, so that the vibration force is difficult to transfer to the wall body of the converter shell, and the noise is further reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of power electronics applications, and particularly relates to a bidirectional DC / DC converter. Background Art

[0002] The use of electronic devices has grown from scratch and spread from partial applications to every corner of people's daily life, study, and work, becoming an indispensable part of people's lives. Most electronic devices rely on power supply. Currently, power supplies have problems such as large volume, non-adjustability, low efficiency, and low safety performance. Designing a bidirectional DC / DC converter, which is a switching power supply device that can achieve "one device with two functions" and is a DC-DC converter that can operate in two quadrants, enables bidirectional energy flow and transmission. With the progress and development of science and technology, the demand for bidirectional DC / DC converters has gradually increased, and its main application scenarios include electric vehicle power systems, DC uninterruptible power supply systems, aerospace power systems, etc. Based on the Buck circuit, MOS transistors are used to replace its diodes, integrating Buck and Boost converters in terms of circuit topology to achieve bidirectional DC / DC conversion. At the same time, a single-chip microcomputer is used as the main controller, meeting the requirements of system digitization and miniaturization, and greatly improving the usage efficiency and safety.

[0003] Since the bidirectional DC / DC converter performs high-frequency switching operations through controllable switches, it generates a relatively high amount of heat during operation. When the heat is higher than 60 °C, it will cause the components inside the bidirectional DC / DC converter to age faster, performance to decline, and even be damaged. In the prior art, a fan is usually used to dissipate heat from the bidirectional DC / DC converter, but there is noise during the operation of the fan, which affects the use.

[0004] Therefore, a bidirectional DC / DC converter is proposed to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a bidirectional DC / DC converter with a simple structure and reasonable design to solve the problem that in the prior art, a fan is usually used to dissipate heat from the bidirectional DC / DC converter, but there is noise during the operation of the fan, which affects the use.

[0006] The present invention achieves the above purpose through the following technical solutions:

[0007] A bidirectional DC / DC converter includes a converter housing. A lid is detachably installed on the front side of the converter housing. First heat dissipation holes and second heat dissipation holes are respectively arranged on both sides of the converter housing. A fan blade mechanism for dissipating heat from the components installed in the converter housing is arranged inside the converter housing. The fan blade mechanism includes a power shaft and fan blades. The fan blades are fixedly connected to the outer ring of the power shaft. One end of the power shaft is rotatably connected and fixed in position, and a second magnet is fixedly arranged at the other end of the power shaft.

[0008] A driving mechanism for providing power to the fan blade mechanism is also arranged in the converter housing. The driving mechanism includes a motor and a first magnet. The first magnet is fixedly connected to the rotating shaft of the motor. The first magnet and the second magnet attract each other and are coaxially distributed. There is a gap between the first magnet and the second magnet.

[0009] Preferably, a support frame is arranged inside the converter housing. A rubber pad is fixedly arranged on the upper surface of the support frame. The rubber pad fits against the top wall of the converter housing. The upper end of the support frame is fixedly installed at the top of the converter housing. The motor is fixedly installed at the lower end position of the support frame.

[0010] Preferably, a rotating sleeve is fixedly arranged on the inner wall of the converter housing. The power shaft is rotatably arranged in the rotating sleeve.

[0011] Preferably, a protection box is fixedly installed on the side inner wall of the converter housing through screws. The protection box covers the outside of the fan blade mechanism. The second heat dissipation hole is communicated with the protection box. An air groove is arranged on the side of the protection box away from the second heat dissipation hole.

[0012] Preferably, both the first heat dissipation hole and the second heat dissipation hole include a first groove body and a second groove body. Both the first groove body and the second groove body are in a rectangular groove body structure. The first groove body and the second groove body are communicated with each other. And the sides of the first groove body and the second groove body away from each other are respectively communicated with the outside and the inside of the converter housing. The length and width dimensions of the first groove body are respectively larger than those of the second groove body. A filter layer is arranged at one end of the first groove body close to the second groove body. The upper end of the filter layer is fixedly installed at the top of the first groove body. The lower end of the filter layer is movably attached to the bottom surface of the first groove body.

[0013] Preferably, a baffle is fixedly arranged on the bottom surface of the first groove body away from the second groove body.

[0014] The beneficial effect of the present invention is that: since there is a gap between the first magnet and the second magnet, the fan blades are driven to rotate by the magnetic attraction method, which can reduce the generation of noise, with low noise or even silent, without affecting the use.

[0015] In the present invention, due to the elastic buffering effect of the rubber pad, the vibration force is difficult to be transmitted to the wall of the converter housing, thereby further reducing the noise.

[0016] The present invention achieves the purpose of not only preventing dust from entering the interior of the converter housing but also enabling the dust inside the converter housing to be discharged.

[0017] In the present invention, a baffle is fixedly arranged on the bottom surface of one end of the first groove body far away from the second groove body. The baffle is used to block the filter layer to prevent the opening of the filter layer from being too large, which not only ensures that dust can be discharged to the outside of the converter housing but also avoids the phenomenon of dust entering due to the too large opening when the filter layer is inclined.

[0018] In the present invention, since the filter layer can be inclined and open a certain gap, the efficiency of heat discharge is improved, taking into account both dust removal and heat dissipation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of the bidirectional DC / DC converter of the present invention;

[0020] Figure 2 is a schematic internal structure diagram of the bidirectional DC / DC converter of the present invention;

[0021] Figure 3 is a schematic structural diagram of the converter housing of the present invention;

[0022] Figure 4 is a cross-sectional view of the bidirectional DC / DC converter of the present invention;

[0023] Figure 5 is of the present invention Figure 4 magnified schematic diagram of the structure at A;

[0024] Figure 6 is of the present invention Figure 4 magnified schematic diagram of the structure at B;

[0025] Figure 7 is a schematic structural diagram when the filter layer is opened in the present invention;

[0026] Figure 8 is a schematic diagram of the bidirectional DC / DC converter module of the present invention.

[0027] In the drawings: converter housing 1, lid 2, first heat dissipation hole 3, first groove body 31, second groove body 32, second heat dissipation hole 4, protection box 5, air groove 6, support frame 7, baffle 8, filter layer 9, rubber pad 10, motor 11, first magnet 12, second magnet 13, power shaft 14, rotating sleeve 15, fan blade 16. DETAILED DESCRIPTION OF THE INVENTION

[0028] The present application will be further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0029] As Figures 1 to 8 shown, the present invention discloses a bidirectional DC / DC converter, which includes a converter housing 1. Components such as capacitors, inductors, controllable switches, and charge pumps are installed inside the converter housing 1. Usually, a synchronous Buck-Boost circuit, a drive circuit, a control circuit, and an auxiliary power supply circuit are also included inside the converter housing 1. The input end of the auxiliary power supply circuit is connected to the mains power supply, and the output end of the auxiliary power supply circuit is connected to the input end of the control circuit. The output end of the control circuit is connected to the input end of the drive circuit. The output end of the drive circuit is connected to the input end of the synchronous Buck-Boost circuit. A voltage and current detection circuit is also connected to the input end of the control circuit. The output end of the synchronous Buck-Boost circuit is connected to a DC and a lithium battery pack. The output ends of the DC and the lithium battery pack are connected to the input end of the voltage and current detection circuit. A key circuit is also connected to the input end of the control circuit. The key circuit is a mechanism commonly used in the prior art for controlling and will not be limited here. The output end of the control circuit is connected to a display circuit.

[0030] It should be noted that the rated voltage of the lithium battery pack is 12V, the rated capacity is 5000mAh, the DC specification is a 36V DC power supply, and the control circuit is an Atmega128 single-chip microcomputer.

[0031] The 220V alternating current first passes through a Mean Well power rectification module to output a 48V DC voltage. Then, through the power management chip TPS54360, the power management chip TPS54360 is a DC-DC buck voltage regulator, which can convert the 48V DC voltage into a 12V DC voltage. The 12V DC voltage outputs a voltage of 3.3V after passing through the low-dropout regulator AMS1117-3.3 to supply power to each control circuit.

[0032] The main control circuit outputs a PWM wave signal, drives the Buck circuit and the Boost circuit through the half-bridge driver IR2104, and outputs the required voltage and current values. At the same time, the voltage and current are sampled by the dual-channel OPA2277UA and the current sensing amplifier INA211, realizing the accurate acquisition of the current and voltage in the circuit. Finally, the real-time data is displayed on the liquid crystal screen. The information of the key circuit is directly sent to the main control circuit, and the main control circuit makes a response to achieve the data adjusted by the key.

[0033] For other components in the converter housing 1, they will not be elaborated here; a lid 2 is detachably installed on the front side of the converter housing 1, which facilitates the maintenance and inspection of components when the lid 2 is opened.

[0034] On both sides of the converter housing 1, a first heat dissipation hole 3 and a second heat dissipation hole 4 are respectively provided. A fan blade mechanism for dissipating heat from the components installed in the converter housing 1 is arranged inside the converter housing 1. When the fan blade mechanism is started, air is sucked in from the second heat dissipation hole 4 into the interior of the converter housing 1. After dissipating heat from the components, the heat is discharged from the first heat dissipation hole 3 to achieve the purpose of heat dissipation.

[0035] To solve the problem that in the prior art, a fan is usually used to dissipate heat from a bidirectional DC / DC converter, but there is noise during the operation of the fan, which affects the use. In the present invention, the fan blade mechanism includes a power shaft 14 and fan blades 16. The fan blades 16 are fixedly connected to the outer ring of the power shaft 14. One end of the power shaft 14 is rotatably connected and fixed in position. A second magnet 13 is fixedly provided at the other end of the power shaft 14; a driving mechanism for providing power to the fan blade mechanism is also arranged in the converter housing 1. The driving mechanism includes a motor 11 and a first magnet 12. The first magnet 12 is fixedly connected to the rotating shaft of the motor 11. The first magnet 12 and the second magnet 13 attract each other and are coaxially distributed. A gap is left between the first magnet 12 and the second magnet 13; when the motor 11 is started, the first magnet 12 can be driven to rotate by the rotating shaft. Since the first magnet 12 and the second magnet 13 attract each other and are coaxially distributed, when the first magnet 12 rotates, the second magnet 13 follows. During the rotation of the second magnet 13, the power shaft 14 can be driven to rotate. When the power shaft 14 rotates, the fan blades 16 rotate to achieve the purpose of driving the air flow. In the present invention, since a gap is left between the first magnet 12 and the second magnet 13, the fan blades 16 are driven to rotate by the magnetic attraction method, which can reduce the generation of noise, with low noise or even silent, without affecting the use.

[0036] It should be noted that although the non-contact transmission method will increase the loss during the power transmission process, usually the power transmission efficiency is within 30%. However, since the overall volume of the bidirectional DC / DC converter is not large, a motor with a very high power is not required to achieve heat dissipation. Although the power transmission efficiency is low, it is sufficient to supply heat dissipation for the bidirectional DC / DC converter.

[0037] Furthermore, considering that there is another source of noise when the fan blade 16 rotates to dissipate heat from the components: the motor 11. Therefore, in the present invention, a support frame 7 is provided inside the converter housing 1. A rubber pad 10 is fixedly arranged on the upper surface of the support frame 7. The rubber pad 10 is in contact with the top wall of the converter housing 1. The upper end of the support frame 7 is fixedly installed on the top of the converter housing 1. The motor 11 is fixedly installed at the lower end of the support frame 7. When the motor 11 starts to vibrate, due to the elastic buffering effect of the rubber pad 10, the vibration force is difficult to be transmitted to the wall of the converter housing 1, thereby further reducing the noise.

[0038] It should be noted that although the rubber pad 10 allows the motor 11 to swing up and down to a certain extent, the swing is controlled within a reasonable range and does not affect the phenomenon of the attraction drive between the first magnet 12 and the second magnet 13. Specifically, the swing range can be achieved by controlling the thickness of the rubber pad 10, which will not be elaborated here.

[0039] In the present invention, a rotating sleeve 15 is fixedly arranged on the inner wall of the converter housing 1. The power shaft 14 is rotatably arranged in the rotating sleeve 15. The power shaft 14 can also be connected to the converter housing 1 by means of a ball bearing or the like, which is not limited here.

[0040] In order to improve the heat dissipation efficiency of the components, multiple sets of fan blade mechanisms can be provided. The multiple sets of fan blade mechanisms can be protected by a protection box 5. Specifically, the protection box 5 is fixedly installed on the inner side wall of the converter housing 1 by screws. The protection box 5 covers the outside of the fan blade mechanism to prevent interference between the fan blade mechanism and the components inside the converter housing 1. The second heat dissipation hole 4 is communicated with the protection box 5. A wind groove 6 is provided on one side of the protection box 5 away from the second heat dissipation hole 4. When the external wind passes through the second heat dissipation hole 4, it first enters the protection box 5 and then is sucked by the fan blade mechanism to the wind groove 6 and discharged into the interior of the converter housing 1.

[0041] Considering that the converter housing 1 has a first heat dissipation hole 3 and a second heat dissipation hole 4, and dust is likely to enter at the first heat dissipation hole 3 and the second heat dissipation hole 4, resulting in more dust inside the converter housing 1 and reducing the heat dissipation efficiency of components. Therefore, in the present invention, the structures of the first heat dissipation hole 3 and the second heat dissipation hole 4 are improved as follows: The first heat dissipation hole 3 and the second heat dissipation hole 4 both include a first groove body 31 and a second groove body 32. The first groove body 31 and the second groove body 32 are both rectangular groove structures. The first groove body 31 and the second groove body 32 are communicated with each other. And the surfaces of the first groove body 31 and the second groove body 32 away from each other are respectively communicated with the outside and the inside of the converter housing 1. The length and width dimensions of the first groove body 31 are respectively larger than those of the second groove body 32. A filter layer 9 is provided at one end of the first groove body 31 close to the second groove body 32. The upper end of the filter layer 9 is fixedly installed on the top of the first groove body 31, and the lower end of the filter layer 9 is movably attached to the bottom surface of the first groove body 31. When air enters through the second heat dissipation hole 4, the wind force will push the filter layer 9 to press against the inner wall of the first groove body 31 at the end close to the second groove body 32, and the filter layer 9 completely blocks the second groove body 32, so that external dust is not easily introduced into the inside of the converter housing 1. When the wind force is discharged from the first heat dissipation hole 3, the wind force will push the filter layer 9 to tilt towards the side away from the second groove body 32. At this time, the lower end of the filter layer 9 is separated from the lower end of the first groove body 31, and the dust inside the converter housing 1 can be discharged from the gap between the lower end of the filter layer 9 and the lower end of the first groove body 31, achieving the purpose of not only preventing dust from entering the inside of the converter housing 1 but also enabling the dust inside the converter housing 1 to be discharged.

[0042] It should be noted that the filter layer 9 is a filter cotton layer, a filter net, etc., and has a certain elastic deformation ability. When the wind blows the filter layer 9, the filter layer 9 can be driven to tilt.

[0043] Furthermore, a baffle 8 is fixedly provided on the bottom surface of the first groove body 31 at the end away from the second groove body 32. The baffle 8 is used to block the filter layer 9 to prevent the opening of the filter layer 9 from being too large, which not only ensures that the dust can be discharged to the outside of the converter housing 1 but also avoids the phenomenon of dust entering due to the too large opening when the filter layer 9 tilts.

[0044] And because the filter layer 9 can tilt and open a certain gap, the heat dissipation efficiency is improved to a certain extent, taking into account both dust removal and heat dissipation, replacing the method in the prior art of fixedly setting a filter net or filter cotton in the first heat dissipation hole 3 or the second heat dissipation hole 4, which will affect the heat dissipation efficiency to a certain extent.

[0045] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention.

Claims

1. A bidirectional DC / DC converter, comprising a converter housing (1), a cover (2) being detachably mounted on the front side of the converter housing (1), a first heat dissipation hole (3) and a second heat dissipation hole (4) being respectively arranged on both sides of the converter housing (1), characterized in that: A fan blade mechanism for dissipating heat for components installed in the converter housing (1) is arranged inside the converter housing (1), the fan blade mechanism comprising a power shaft (14) and a fan blade (16), the fan blade (16) being fixedly connected to the outer ring of the power shaft (14), one end of the power shaft (14) being rotatably connected and fixed in position, and a second magnet (13) being fixedly arranged at the other end of the power shaft (14); The converter housing (1) is also provided with a driving mechanism for providing power to the fan mechanism, the driving mechanism comprising a motor (11) and a first magnet (12), the first magnet (12) being fixedly connected to the rotating shaft of the motor (11), the first magnet (12) and the second magnet (13) being attracted to each other and coaxially distributed, and a gap being left between the first magnet (12) and the second magnet (13).

2. A bidirectional DC / DC converter according to claim 1, characterized in that: A support frame (7) is provided inside the converter housing (1); a rubber pad (10) is fixedly provided on the upper surface of the support frame (7); the rubber pad (10) is in contact with the top wall of the converter housing (1); the upper end of the support frame (7) is fixedly mounted on the top of the converter housing (1); and the motor (11) is fixedly mounted at the lower end of the support frame (7).

3. A bidirectional DC / DC converter according to claim 1, characterized in that: A rotating sleeve (15) is fixedly arranged on the inner wall of the converter housing (1), and the power shaft (14) is rotatably arranged in the rotating sleeve (15).

4. A bidirectional DC / DC converter according to claim 1, characterized in that: A protection box (5) is fixedly mounted on the inner wall of the side of the converter housing (1) by means of screws; the protection box (5) is arranged outside the fan blade mechanism; the second heat dissipation hole (4) is connected to the protection box (5); and a wind slot (6) is arranged on a side of the protection box (5) away from the second heat dissipation hole (4).

5. The bidirectional DC / DC converter according to claim 1, characterized in that: The first heat dissipation hole (3) and the second heat dissipation hole (4) both comprise a first slot body (31) and a second slot body (32); the first slot body (31) and the second slot body (32) both present a rectangular slot body structure; the first slot body (31) and the second slot body (32) are arranged to be connected to each other; and the first slot body (31) and the second slot body (32) are respectively connected to the outside and the inside of the converter housing (1); the length and width of the first slot body (31) are respectively greater than the length and width of the second slot body (32); a filter layer (9) is arranged at one end of the first slot body (31) close to the second slot body (32); the upper end of the filter layer (9) is fixedly mounted on the top of the first slot body (31); and the lower end of the filter layer (9) is movably fitted with the bottom surface of the first slot body (31).

6. A bidirectional DC / DC converter according to claim 5, characterized in that: A baffle (8) is fixedly disposed on the bottom surface of one end of the first trough body (31) away from the second trough body (32).

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