Heat dissipation structure of switching type power supply

Abstract

A heat dissipation structure of a switching type power supply comprises a transformer, a front-stage composition circuit, a rear-stage composition circuit, at least one heat dissipation fan, a plurality of temperature sensing pieces and a temperature control module. One of the plurality of temperature sensing elements arranged corresponding to the preceding-stage composition circuit senses the temperature of the preceding-stage composition circuit so as to provide a first temperature control factor, and one of the plurality of temperature sensing elements arranged corresponding to the backward-stage composition circuit senses the temperature of the backward-stage composition circuit so as to provide a second temperature control factor. The temperature control module controls the rotating speed of the at least one cooling fan based on the first temperature control factor and the second temperature control factor, the first temperature control factor enables the rotating speed of the at least one cooling fan to be larger than or equal to 0, and the second temperature control factor enables the rotating speed of the at least one cooling fan to be smaller than or equal to 1.

Description

TECHNICAL FIELD

[0001] The utility model relates to a heat dissipation frame of switching power supply, in particular to a heat dissipation frame which takes the heat dissipation of the front-stage circuit into the fan driving control factor. BACKGROUND

[0002] Current switching power supplies on the market are all provided with temperature protection mechanisms, such as overheat power-off, configuration of heat dissipation fans, etc. However, the current temperature protection mechanisms are generally based on the temperature rise state of the transformer secondary side circuit to determine the start, and the aforementioned temperature protection mechanism sets a temperature sensing element at the transformer secondary side circuit. The components of the secondary side circuit generate heat when running, and the temperature sensing element senses the temperature of the secondary side circuit. Once the detection result of the temperature sensing element reaches the full-speed heat dissipation condition, the heat dissipation fan is triggered to perform heat dissipation.

[0003] The heat source of the power supply is not only distributed in the secondary side circuit. When the primary side circuit runs, the components belonging to the primary side circuit will also generate heat. However, the current temperature protection mechanism of the power supply does not take the primary side circuit into the judgment of heat dissipation start, which means that the components belonging to the primary side circuit are not protected from overheating. The ineffective heat dissipation of the primary side circuit will lead to the increase of power loss of the primary side circuit, affecting the input voltage. In the current switching power supply architecture with a wide input voltage range, the only way to solve the heat accumulation problem is to increase the rated power of the components, which indirectly leads to the increase of component cost.

[0004] In addition, Taiwan TW M390647U discloses a technical means for temperature protection of a power supply based on the secondary side circuit and the ambient temperature. According to the description of the case, the heat dissipation method of the power supply takes the ambient temperature into control, but the ambient temperature cannot reflect the temperature of the primary side circuit in real time, and the case must start the corresponding heat dissipation when the ambient temperature exceeds the condition, which leads to the fact that the primary side temperature cannot obtain good heat dissipation effect, affecting the reliability of the power supply. SUMMARY

[0005] The main purpose of the utility model is to solve the problem that the heat dissipation in the current switching power supply is not taken into the temperature rise state of the transformer front-stage circuit as a heat dissipation control factor.

[0006] To achieve the above object, the utility model provides an exchange type power supply's heat dissipation framework, contains a transformer, a front stage component circuit connected with the transformer's primary side, a back stage component circuit connected with the transformer's secondary side, at least one heat dissipation fan, a plurality of temperature sensing piece and a temperature control module electrically connected with the at least one heat dissipation fan. The at least one heat dissipation fan is configured to be able to provide a heat dissipation airflow for the transformer, the front stage component circuit and the back stage component circuit, the plurality of temperature sensing piece is arranged respectively corresponding to the front stage component circuit and the back stage component circuit, one of the plurality of temperature sensing piece arranged corresponding to the front stage component circuit mainly feels the temperature of the front stage component circuit to provide a first temperature control factor, one of the plurality of temperature sensing piece arranged corresponding to the back stage component circuit mainly feels the temperature of the back stage component circuit to provide a second temperature control factor. The temperature control module obtains the first temperature control factor and the second temperature control factor, and the temperature control module controls the rotation speed of the at least one heat dissipation fan based on the first temperature control factor and the second temperature control factor, wherein the first temperature control factor makes the rotation speed of the at least one heat dissipation fan greater than or equal to 0, and the second temperature control factor makes the rotation speed of the at least one heat dissipation fan less than or equal to 1, 0 represents stop rotating, and 1 represents full speed rotating.

[0007] In an embodiment, the heat dissipation framework of the exchange type power supply further comprises an optical coupling connected between one of the plurality of temperature sensing pieces arranged corresponding to the front stage component circuit and the temperature control module.

[0008] In an embodiment, the heat dissipation framework of the exchange type power supply further comprises a signal amplification circuit connected between one of the plurality of temperature sensing pieces arranged corresponding to the front stage component circuit and the optical coupling.

[0009] In an embodiment, the heat dissipation framework of the exchange type power supply further comprises a signal comparison circuit connected between one of the plurality of temperature sensing pieces arranged corresponding to the front stage component circuit and the optical coupling.

[0010] In an embodiment, the plurality of temperature sensing pieces are thermistors.

[0011] In an embodiment, the temperature control module comprises a computing chip, and the computing chip stores at least one computing program therein, and the at least one computing program controls the rotation speed of the at least one heat dissipation fan based on the first temperature control factor and the second temperature control factor.

[0012] In an embodiment, the plurality of temperature sensing pieces are arranged in a parallel circuit, and the temperature control module is connected to a parallel node of the parallel circuit, and a voltage signal of the parallel node is a mixture of the first temperature control factor and the second temperature control factor.

[0013] According to the utility model content disclosed previously, compared with the prior art, the utility model has the following characteristics: the heat dissipation frame of the utility model is provided with the plurality of temperature sensing elements, the temperature control module of the utility model obtains the first temperature control factor and the second temperature control factor, and drives the rotation of the at least one heat dissipation fan by the first temperature control factor and the second temperature control factor. Wherein, the first temperature control factor is greater than or equal to 0, and the second temperature control factor is less than or equal to 1. Therefore, the utility model is not only determined by the temperature of the rear-stage component circuit or the internal environment temperature of the switching power supply to determine the operation of the at least one heat dissipation fan, but also takes the temperature of the front-stage component circuit as a factor of heat dissipation control. Compared with the prior art, the utility model can effectively improve the power reliability of the switching power supply. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 Unit diagram of an embodiment of the utility model;

[0015] Figure 2 Signal comparison circuit unit schematic diagram of an embodiment of the utility model;

[0016] Figure 3 Signal comparison circuit schematic diagram of an embodiment of the utility model;

[0017] Figure 4 Signal amplification circuit unit schematic diagram of an embodiment of the utility model;

[0018] Figure 5 Signal amplification circuit schematic diagram of an embodiment of the utility model;

[0019] Figure 6 Temperature sensing element parallelly arranged schematic diagram of an embodiment of the utility model.

[0020] SYMBOL DESCRIPTION

[0021] 200: switching power supply

[0022] 20: heat dissipation frame

[0023] 21: transformer

[0024] 22: front-stage component circuit

[0025] 23: rear-stage component circuit

[0026] 24: heat dissipation fan

[0027] 25: temperature sensing element

[0028] 26: temperature sensing element

[0029] 27: temperature control module

[0030] 28: light coupling

[0031] 29: signal comparison circuit

[0032] 31: signal amplification circuit

[0033] 32: node DETAILED DESCRIPTION

[0034] The utility model in detail explains and technical content, present cooperation drawing explanation is as follows:

[0035] Please refer to Figure 1 The utility model provides a heat dissipation frame 20 of switching power supply 200, including a transformer 21, a front stage component circuit 22, a back stage component circuit 23, at least one heat dissipation fan 24, multiple temperature sensing parts 25, 26 and a temperature control module 27.The front stage and back stage of the preceding text are separated with the transformer 21, and according to general knowledge, the front stage component circuit 22 is directly or indirectly electrically connected to the primary side of the transformer 21, the front stage component circuit 22 accepts external power, and the front stage component circuit 22 can include a rectifier circuit, a power factor adjustment circuit, an LLC resonant circuit and / or an associated control circuit.In the same way, the back stage component circuit 23 is directly or indirectly electrically connected to the secondary side of the transformer 21, and the back stage component circuit 23 outputs power, and the back stage component circuit 23 can include at least one power conversion circuit and / or an associated control circuit.The at least one heat dissipation fan 24 is located in a shell of the switching power supply 200, and the at least one heat dissipation fan 24 is configured to provide a heat dissipation airflow to the space in the shell of the switching power supply 200, that is to say, the at least one heat dissipation fan 24 provides heat dissipation to the transformer 21, the front stage component circuit 22 and the back stage component circuit 23 in the shell when starting, and on the other hand, multiple air holes are formed on the shell, and the at least one heat dissipation fan 24 can be arranged corresponding to at least one of the multiple air holes.

[0036] The plurality of temperature sensors 25, 26 are respectively arranged near the front-stage component circuit 22 and the back-stage component circuit 23. For example, one of the plurality of temperature sensors 25 arranged near the front-stage component circuit 22 is arranged near an electronic component with a significant temperature rise in the front-stage component circuit 22, and mainly senses the temperature of the electronic component to provide a first temperature control factor. One of the plurality of temperature sensors 26 arranged near the back-stage component circuit 23 is arranged near an electronic component with a significant temperature rise in the back-stage component circuit 23, and mainly senses the temperature of the electronic component to provide a second temperature control factor. The relationship between the plurality of temperature sensors 25, 26 and the front-stage component circuit 22 and the back-stage component circuit 23 must be able to sense the temperature of one of the front-stage component circuit 22 and the back-stage component circuit 23.

[0037] The temperature control module 27 is electrically connected to the at least one cooling fan 24, and obtains the first temperature control factor and the second temperature control factor. The temperature control module 27 controls the rotation speed of the at least one cooling fan 24 based on the first temperature control factor and the second temperature control factor. The first temperature control factor makes the rotation speed of the at least one cooling fan 24 greater than or equal to 0, and the second temperature control factor makes the rotation speed of the at least one cooling fan 24 less than or equal to 1, where 0 represents stopping rotation, and 1 represents full-speed rotation.

[0038] At the beginning of the operation of the switching power supply 200, the front-stage component circuit 22 and the back-stage component circuit 23 are powered on and generate temperature rises. The temperature control module 27 simultaneously controls the at least one cooling fan 24 based on the first temperature control factor and the second temperature control factor, so that when the front-stage component circuit 22 (i.e., the power factor adjustment circuit) generates a significant temperature rise, early cooling can be performed to avoid the accumulation of subsequent waste heat, which seriously affects the power supply reliability of the switching power supply 200. The control of the aforementioned early cooling is based on the first temperature control factor, and the rotation speed control of the at least one cooling fan 24 corresponding to the first temperature control factor is not mainly for full-speed operation, but for making the at least one cooling fan 24 rotate and perform moderate cooling. The second temperature control factor is used as a starting basis for judging the temperature rise of the back-stage component circuit 23 after startup and the need for cooling. The control generated by the temperature control module 27 based on the first temperature control factor and the second temperature factor can be step control or linear control. In the case of step control, the temperature control module 27 divides the rotation speed of the at least one cooling fan 24 into multiple stages, and the at least one cooling fan 24 works at one of the multiple predefined rotation speeds. In the case of linear control, the temperature control module 27 makes the rotation speed of the at least one cooling fan 24 continuously change linearly.

[0039] As known from the foregoing, the heat dissipation frame 20 no longer determines the operation of the at least one heat dissipation fan 24 according to the temperature of the post-stage component circuit 23 only, but also takes the temperature rise condition of the pre-stage component circuit 22 into consideration for speed control, so that the pre-stage component circuit 22 can obtain effective heat dissipation, and the power supply reliability of the switching power supply 200 can be improved compared with the prior art. In addition to the foregoing, the temperature of the pre-stage component circuit 22 is taken into consideration for speed control, and the pre-heat dissipation of the post-stage component circuit 23 is also realized to a certain extent.

[0040] In an embodiment, the plurality of temperature sensing elements 25, 26 are thermistors, respectively, which respectively sense the temperature of the pre-stage component circuit 22 and the temperature of the post-stage component circuit 23, and change their own resistance values with the change of the foregoing temperatures, so that the temperature control module 27 receives different voltage signals, and controls the at least one heat dissipation fan 24 according to different voltage signals. Please refer to Figures 2 to 5 In an embodiment, the heat dissipation frame 20 comprises an optical coupling element 28 connected between one of the plurality of temperature sensing elements (25) arranged corresponding to the pre-stage component circuit 22 and the temperature control module 27, and the optical coupling element 28 provides isolation effect between one of the plurality of temperature sensing elements (25) arranged corresponding to the pre-stage component circuit 22 and the temperature control module 27. In an embodiment, as shown in Figure 2 The heat dissipation frame 20 further comprises a signal comparison circuit 29 connected between one of the plurality of temperature sensing elements (25) arranged corresponding to the pre-stage component circuit 22 and the optical coupling element 28, and the signal comparison circuit 29 compares the first temperature control factor (i.e. voltage signal) generated by one of the plurality of temperature sensing elements (25) arranged corresponding to the pre-stage component circuit 22 with a reference voltage (Vref), and then transmits the comparison result to the optical coupling element 28. The circuit schematic diagram of an embodiment of the signal comparison circuit 29 is shown in Figure 3 In another embodiment, please refer to Figure 4 The heat dissipation frame 20 comprises a signal amplification circuit 31 connected between one of the plurality of temperature sensing elements (25) arranged corresponding to the pre-stage component circuit 22 and the optical coupling element 28, and the signal amplification circuit 31 amplifies the signal of one of the plurality of temperature sensing elements (25) arranged corresponding to the pre-stage component circuit 22, and then transmits the amplified signal to the optical coupling element 28, so as to facilitate the control of the temperature control module 27 at the rear end, and avoid the problem that the first temperature factor signal is not obvious and affects the subsequent control. The circuit schematic diagram of an embodiment of the signal amplification circuit 31 is shown in Figure 5 In an embodiment, the signal comparison circuit 29 and the signal amplification circuit 31 can also be implemented simultaneously, and the signal amplification circuit 31 can be implemented first, and then the signal comparison circuit 29.

[0041] The temperature control module 27 can be implemented by an analog temperature control circuit or a digital temperature control circuit. In the embodiment of the digital temperature control circuit, the temperature control module 27 comprises an operation chip, at least two pins of the operation chip are connected to the temperature sensors 25 and 26. The operation chip stores at least one operation program in a memory, and the operation program is stored in the operation chip in a manner known in the art, which will not be described here. When the operation chip runs the at least one operation program, the voltage of the at least two pins connected to the temperature sensors 25 and 26 is used to determine the rotation speed of the at least one cooling fan 24.

[0042] In an embodiment, referring to Figure 1 and Figure 6 , the temperature sensors 25 and 26 are implemented in parallel circuit, the temperature control module 27 is connected to the parallel node (i.e. one node 32 generated by the parallel connection of the temperature sensors 25 and 26) of the parallel circuit, and the voltage signal of the parallel node is used to control the rotation speed of the at least one cooling fan 24. The voltage signal of the parallel node is a mixture of the first temperature control factor and the second temperature control factor.

Claims

1. A heat dissipation architecture for a switching power supply, characterized by, Comprising: a transformer; a front-stage component circuit connected to a primary side of the transformer; a back-stage component circuit connected to a secondary side of the transformer; at least one cooling fan configured to provide a cooling airflow to the transformer, the front-stage component circuit and the back-stage component circuit; a plurality of temperature sensors respectively arranged corresponding to the front-stage component circuit and the back-stage component circuit, one of the temperature sensors arranged corresponding to the front-stage component circuit is mainly to sense a temperature of the front-stage component circuit to provide a first temperature control factor, one of the temperature sensors arranged corresponding to the back-stage component circuit is mainly to sense a temperature of the back-stage component circuit to provide a second temperature control factor; and a temperature control module electrically connected to the at least one cooling fan, and obtaining the first temperature control factor and the second temperature control factor, the temperature control module controls a rotation speed of the at least one cooling fan based on the first temperature control factor and the second temperature control factor, wherein the first temperature control factor makes the rotation speed of the at least one cooling fan greater than or equal to 0, the second temperature control factor makes the rotation speed of the at least one cooling fan less than or equal to 1, 0 represents stop rotation, and 1 represents full speed rotation. The cooling structure of the switching power supply further comprises an optocoupler connected between one of the temperature sensors arranged corresponding to the front-stage component circuit and the temperature control module.

2. The heat dissipation architecture of a switching power supply as claimed in claim 1, wherein, The cooling structure of the switching power supply further comprises a signal amplification circuit connected between one of the temperature sensors arranged corresponding to the front-stage component circuit and the optocoupler.

3. The heat dissipation architecture of a switching power supply as claimed in claim 2, wherein, The cooling structure of the switching power supply further comprises a signal comparison circuit connected between one of the temperature sensors arranged corresponding to the front-stage component circuit and the optocoupler.

4. The heat dissipation architecture of a switching power supply as claimed in claim 2, wherein, The plurality of temperature sensors are respectively thermistors.

5. The heat dissipation architecture of a switching power supply as claimed in any one of claims 1 to 4, wherein, The temperature control module comprises a computing chip, and at least one computing program is stored in the computing chip, the at least one computing program controls the rotation speed of the at least one cooling fan based on the first temperature control factor and the second temperature control factor.

6. The heat dissipation architecture of a switching power supply as claimed in any one of claims 1 to 4, wherein, The plurality of temperature sensors are arranged in a parallel circuit, and the temperature control module is connected to a parallel node of the parallel circuit, a voltage signal of the parallel node is a mixture of the first temperature control factor and the second temperature control factor.

7. The heat dissipation architecture of a switching power supply as claimed in any one of claims 1 to 4, wherein, ​

Images