US-12625011-B2 - Temperature detection system and on board charger

Abstract

The present application provides a temperature detection system and an on board charger, the system including a heat transfer element and a temperature sensor; the heat transfer element and the temperature sensor are both located on a printed circuit board. The heat transfer element is thermally connected to the temperature sensor, and is also configured to thermally connect to the power device on the printed circuit board. The heat transfer element is configured to transfer a temperature of the power device to the temperature sensor, so that the temperature sensor detects the temperature of the power device. The heat transfer element is an electrically insulating element. The heat transfer element is thermally connected to the power device and temperature sensor.

Inventors

• Zhen Zhou
• Peiai You
• Jianhong Chen

Assignees

• DELTA ELECTRONICS (SHANGHAI) CO., LTD.

Dates

Publication Date

20260512

Application Date

20211027

Priority Date

20201208

Claims (20)

1. 1 . A temperature detection system, comprising: a heat transfer element and a temperature sensor; the heat transfer element and the temperature sensor are both located on a printed circuit board; the heat transfer element is thermally connected to the temperature sensor, and also configured to thermally connect to a power device on the printed circuit board; the heat transfer element is configured to transfer a temperature of the power device to the temperature sensor, so that the temperature sensor detects a temperature of the power device; the heat transfer element is an electrically insulating element; wherein the temperature sensor is located between a plurality of heat transfer elements and is directly physically connected to a plurality of heat transfer elements to improve detection speed of the temperature sensor, the plurality of heat transfer elements are directly physically connected to the power device.
2. 2 . The temperature detection system according to claim 1 , wherein the power device, the heat transfer element and the temperature sensor are all welded on the printed circuit board, a pad of the heat transfer element is thermally connected to a pad of the power device, another pad of the heat transfer element is thermally connected to a pad of the temperature sensor.
3. 3 . The temperature detection system according to claim 1 , wherein the heat transfer element and the temperature sensor are an integrated package structure.
4. 4 . The temperature detection system according to claim 1 , wherein the heat transfer element is a surface mounted integrated package structure.
5. 5 . The temperature detection system according to claim 3 , wherein the temperature sensor is located on the heat transfer element.
6. 6 . The temperature detection system according to claim 5 , wherein the temperature sensor is mounted on a cladding of the heat transfer element by means of welding.
7. 7 . The temperature detection system according to claim 1 , wherein a plurality of power devices are disposed on the printed circuit board, and the heat transfer element is thermally connected to a power device with the highest temperature.
8. 8 . The temperature detection system according to claim 1 , wherein a material of the heat transfer element comprises aluminum oxide and/or aluminum nitride.
9. 9 . The temperature detection system according to claim 1 , wherein the temperature detection system is disposed on an on board charger.
10. 10 . An on board charger, comprising: a power device, a printed circuit board and a temperature detection system; wherein the temperature detection system comprises a heat transfer element and a temperature sensor; the heat transfer element and the temperature sensor are both located on a printed circuit board; the heat transfer element is thermally connected to the temperature sensor, and also configured to thermally connect to a power device on the printed circuit board; the heat transfer element is configured to transfer a temperature of the power device to the temperature sensor, so that the temperature sensor detects a temperature of the power device; the heat transfer element is an electrically insulating element; the temperature detection system and the power device are located on the printed circuit board; wherein the temperature sensor is located between a plurality of heat transfer elements and is directly physically connected to a plurality of heat transfer elements to improve detection speed of the temperature sensor, the plurality of heat transfer elements are directly physically connected to the power device.
11. 11 . The on board charger according to claim 10 , wherein the power device, the heat transfer element and the temperature sensor are all welded on the printed circuit board, a pad of the heat transfer element is thermally connected to a pad of the power device, another pad of the heat transfer element is thermally connected to a pad of the temperature sensor.
12. 12 . The on board charger according to claim 10 , wherein the heat transfer element and the temperature sensor are an integrated package structure.
13. 13 . The on board charger according to claim 10 , wherein the heat transfer element is a surface mounted integrated package structure.
14. 14 . The on board charger according to claim 12 , wherein the temperature sensor is located on the heat transfer element.
15. 15 . The on board charger according to claim 14 , wherein the temperature sensor is mounted on a cladding of the heat transfer element by means of welding.
16. 16 . The on board charger according to claim 10 , wherein a plurality of power devices are disposed on the printed circuit board, and the heat transfer element is thermally connected to a power device with the highest temperature.
17. 17 . The on board charger according to claim 10 , wherein a material of the heat transfer element comprises aluminum oxide and/or aluminum nitride.
18. 18 . The on board charger according to claim 10 , wherein the temperature detection system is disposed on an on board charger.
19. 19 . The temperature detection system according to claim 1 , wherein, the heat transfer element is perforated, and the temperature sensor is put into a hole to integrate a package structure.
20. 20 . The temperature detection system according to claim 1 , wherein, the heat transfer element has a length of 5.0±0.1 mm, a width of 2.5±0.1 mm and a height of 1.0±0.1 mm; a length and width of a cladding are 2.5±0.1 mm and 0.75=0.25 mm respectively.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to Chinese Patent Application No. 202011423927.8, filed on Dec. 8, 2020, which is hereby incorporated by reference in its entirety. TECHNICAL FIELD The present application relates to the technical field of on board chargers, and in particular, to a temperature detection system and an on board charger. BACKGROUND With the increasing endurance capability of electric vehicles, the power of an on board charger also increases, and the thermal management of products becomes more and more important. A power device is the core component of the on board charger, so it is particularly important to solve the thermal management problem of the power device. The stability of the power device is directly related to the reliability of the whole product. Therefore, when the product is running, it is necessary to monitor the temperature of the power device, and when its temperature is abnormal, the corresponding protection is triggered to ensure that the power device is not damaged due to an excessive temperature. In the prior art, a temperature sensor is placed around a power device to detect a temperature of the power device. Due to a potential difference between the power device and the temperature sensor, it is required to separate a certain distance between a pad of the power device and a pad of the sensor. However, heat transfer between the power device and the sensor is carried out through a printed circuit board, the printed circuit board has poor lateral capacity of heat-transmission, and there is a great heat transfer resistance between the power device and the sensor, which leads to the problem of slow response speed of temperature detection, and the product cannot trigger a protection in time, and the power device being damaged by over-temperature cannot be effectively prevented. SUMMARY The present application provides a temperature detection system and an on board charger to solve the problem of slow response speed of temperature detection. In a first aspect, a temperature detection system, including: a heat transfer element and a temperature sensor; the heat transfer element and the temperature sensor are both located on a printed circuit board; the heat transfer element is thermally connected to the temperature sensor, and is also configured to thermally connect to a power device on the printed circuit board; the heat transfer element is configured to transfer a temperature of the power device to the temperature sensor, so that the temperature sensor detects a temperature of the power device; the heat transfer element is an electrically insulating element. Optionally, the power device, the heat transfer element and the temperature sensor are all welded on the printed circuit board, a pad of the heat transfer element is thermally connected to a pad of the power device, and the pad of the heat transfer element is thermally connected to a pad of the temperature sensor. Optionally, the heat transfer element and the temperature sensor are an integrated package structure. Optionally, the heat transfer element is a surface mounted integrated package structure. Optionally, the temperature sensor is located on the heat transfer element. Optionally, the temperature sensor is mounted on a cladding of the heat transfer element by means of welding. Optionally, one temperature sensor is thermally connected to a plurality of heat transfer elements, and the plurality of heat transfer elements are thermally connected to one power device. Optionally, a plurality of power devices are disposed on the printed circuit board, and the heat transfer element is thermally connected to a power device with the highest temperature. Optionally, a material of the heat transfer element includes aluminum oxide and/or aluminum nitride. Optionally, the temperature detection system is disposed on an on board charger. In a second aspect, an on board charger, including: a power device, a printed circuit board, and the temperature detection system according to the first aspect and the alternative solutions; where the temperature detection system and the power device are located on the printed circuit board. The present application provides a temperature detection system and an on board charger, the system including a heat transfer element and a temperature sensor; the heat transfer element and the temperature sensor are both located on a printed circuit board. The heat transfer element is thermally connected to the temperature sensor, and is also configured to thermally connect to the power device on the printed circuit board; the heat transfer element is configured to transfer a temperature of the power device to the temperature sensor, so that the temperature sensor detects the temperature of the power device; the heat transfer element is an electrically insulating element. The heat transfer element is thermally connected to the power device and temperature sensor, which qui