48V and 12V integrated vehicle-mounted DCDC system

Abstract

The invention discloses a 48V and 12V integrated vehicle-mounted DCDC system which comprises a power level circuit module, a microcontroller module, a driving circuit module, an auxiliary power supply module, an output anti-backflow module, a sampling circuit module, a communication module, a protection circuit module and an IO wake-up interface. The power level circuit module comprises a high-voltage input module, an EMI filtering module, a full-bridge circuit module and a double-branch output module. The double-branch output module comprises a 48V output branch and a 12V output branch; the 48V output branch comprises an output winding 1, a full-bridge rectifier module, an anti-backflow module 1, an output protection module 1 and a 48V output module; the 12V output branch comprises an output winding 2, a full-bridge rectifier module, an anti-backflow module 2, an output protection module 2 and a 12V output module; in the parking mode, electricity can be directly taken from the high-voltage power battery, different low-voltage systems are charged, and continuous power supply of low-voltage equipment is ensured.

Description

Technical Field

[0001] This invention relates to the field of vehicle power technology, and more particularly to a vehicle DC-DC system integrating 48V and 12V. Background Technology

[0002] With the rapid development of new energy vehicles, the number and power consumption of in-vehicle electrical equipment have increased significantly, including smart cockpits, driver assistance systems, and in-vehicle infotainment systems, leading to a significant increase in the demand for low-voltage power. However, in parking mode, the OBC (On-Board Charger) is usually not working, resulting in the low-voltage battery not being able to continuously replenish power.

[0003] Currently, most automotive DC-DC converters only support a single voltage output, which cannot simultaneously meet the needs of dual-voltage systems. This necessitates the addition of an extra DC-DC module, occupying space and increasing costs. Some new energy vehicles adopt a dual-voltage architecture, where the 12V system handles traditional electrical loads, while the 48V system drives high-power equipment. Traditional automotive 12V and 48V batteries can only be charged and replenished simultaneously through the onboard OBC and the large DC-DC converter. In parking mode, some onboard electrical equipment remains powered on. If the vehicle remains in parking mode for an extended period, the 12V and 48V batteries will be depleted, affecting the vehicle's normal functions. Summary of the Invention

[0004] This application provides a vehicle-mounted DC-DC system that integrates 48V and 12V, solving the problem in the prior art that different low-voltage electrical systems cannot be recharged in parking mode. It enables the system to draw power directly from the high-voltage power battery in parking mode to charge different low-voltage systems and ensure continuous power supply to low-voltage equipment.

[0005] This application provides a 48V and 12V integrated vehicle DC-DC system, including a power stage circuit module, a microcontroller module, a drive circuit module, an auxiliary power supply module, an output reverse current protection module, a sampling circuit module, a communication module, a protection circuit module, and an IO wake-up interface. The power stage circuit module includes a high-voltage input module, an EMI filter module, a full-bridge circuit module, and a dual-branch output module. The dual-branch output module includes a 48V output branch and a 12V output branch; the 48V output branch includes an output winding 1, a full-bridge rectifier module, an anti-backflow module 1, an output protection module 1, and a 48V output module; the 12V output branch includes an output winding 2, a full-bridge rectifier module, an anti-backflow module 2, an output protection module 2, and a 12V output module.

[0006] Preferably, the EMI filtering module includes an input EMI filtering module and an output EMI filtering module; the input EMI filtering module is connected to the high-voltage input module, and the output EMI filtering module includes EMI filtering module 1 and EMI filtering module 2; EMI filtering module 1 is located in the 48V output branch, and EMI filtering module 2 is located in the 12V output branch.

[0007] Preferably, the anti-backflow module 1 and the anti-backflow module 2 are each composed of a set of back-to-back power switching transistors and a driver. The driver is used to drive the back-to-back power switching transistors to turn on and off, and is controlled by the microcontroller module.

[0008] Preferably, the anti-backflow module 1 and the anti-backflow module 2 are each composed of a set of back-to-back diodes, used to prevent current from the external vehicle battery from being injected into the power stage circuit module.

[0009] Preferably, the EMI filter module circuit is equipped with a reverse connection protection circuit module at the front end to protect the vehicle DC-DC system from damage when the input high voltage is reversed.

[0010] Preferably, the 48V output branch is a full-bridge structure; the 12V output branch is a half-bridge structure with a center tap.

[0011] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: This application adopts a dual-branch output module. By using a 48V output branch and a 12V output branch, it effectively solves the problem that some on-board equipment cannot be recharged after the dual-voltage system battery is depleted in parking mode. It enables the vehicle to draw power from the on-board high-voltage power battery in parking mode to efficiently and safely charge the 12V and 48V low-voltage battery systems, thereby ensuring that the vehicle can maintain the normal operation of critical electrical equipment even when parked for a long time, effectively improving the reliability and safety of new energy vehicles. Attached Figure Description

[0012] Figure 1 This is a block diagram of the 48V and 12V integrated vehicle DC-DC system of this application; Figure 2 This is the circuit diagram of the EMI filter module in this application; Figure 3 This is the circuit diagram of the anti-backflow module in this application; Figure 4 This is the circuit diagram of the current sampling module in this application; Figure 5 This is the circuit diagram of the voltage sampling module in this application; Figure 6 This is the circuit diagram of the high-voltage isolation sampling module of this application; Figure 7 This is the circuit diagram of the wake-up input module for this application; Figure 8 This is the circuit diagram of the wake-up output module of this application; Figure 9 This is the circuit diagram of the communication module in this application. Detailed Implementation

[0013] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0014] like Figure 1 As shown, this application discloses a 48V and 12V integrated vehicle DC-DC system, including a power stage circuit module, a microcontroller module, a drive circuit module, an auxiliary power supply module, an output backflow prevention module, a sampling circuit module, a communication module, a protection circuit module, and an IO wake-up interface; The power stage circuit module includes a high-voltage input module, an EMI filter module, a full-bridge circuit module, and a dual-branch output module. The dual-branch output module includes a 48V output branch and a 12V output branch; the 48V output branch includes an output winding 1, a full-bridge rectifier module, an anti-backflow module 1, an output protection module 1, and a 48V output module; the 12V output branch includes an output winding 2, a full-bridge rectifier module, an anti-backflow module 2, an output protection module 2, and a 12V output module.

[0015] The high-voltage input module serves as the source, and the power stage circuit module performs DC-DC isolation conversion, providing one 48V branch output and one 12V branch output for charging the vehicle's small battery and supplying power to the vehicle's low-voltage electrical equipment. The drive circuit module receives control signals from the microcontroller module and uses the auxiliary power module as the power supply to drive the power switching transistors in the power stage circuit module to turn on and off. The sampling circuit module inputs the real-time collected vehicle power battery voltage on the primary side of the power stage circuit module, as well as the output voltage and current of the 48V branch and the 12V branch, to the microcontroller module. The communication module is connected to the microcontroller module for communication between the vehicle's DC-DC converter and other vehicle devices. The protection circuit module is located on the output side of the 48V and 12V branches to provide overcurrent protection when the load on each branch is too heavy.

[0016] like Figure 2As shown, the EMI filtering module includes an input EMI filtering module and an output EMI filtering module. The input EMI filtering module is connected to the high-voltage input module, and the output EMI filtering module includes EMI filtering module 1 and EMI filtering module 2. EMI filtering module 1 is located in the 48V output branch, and EMI filtering module 2 is located in the 12V output branch. The anti-backflow module consists of a set of back-to-back power switching transistors and one or more drivers. The drivers are used to turn the back-to-back power switching transistors on and off, and are controlled by the microcontroller module. Alternatively, the anti-backflow module circuit consists of a set of back-to-back diodes to prevent current from the external vehicle battery from being injected into the vehicle DC-DC power stage module.

[0017] like Figure 3 As shown, the anti-backflow module 1 and anti-backflow module 2 are each composed of a set of back-to-back diodes, which are used to prevent the current from the external vehicle battery from being injected into the power stage circuit module.

[0018] The sampling circuit module includes an output voltage sampling module, a current sampling module, and a high-voltage isolation sampling module; such as Figure 5 As shown, the output voltage sampling module is connected to output winding 1 and output winding 2, and is used to collect real-time voltage data of the output windings and output it to the microcontroller module to monitor the load of each branch and prevent overload; as Figure 4 As shown, the current sampling module connects output winding 1 and output winding 2, and is used to collect real-time current data of the output windings and output it to the microcontroller module to monitor the load of each branch and prevent overload; as Figure 6 As shown, the high-voltage isolation sampling module is connected to the input EMI filter module and is used to collect the voltage data of the high-voltage input, isolate and detect the input voltage, and ensure the safety of the high-voltage side.

[0019] The 48V output branch is a full-bridge structure; the 12V output branch is a half-bridge structure.

[0020] The 12V output branch has a half-bridge structure with a center tap.

[0021] The I / O wake-up interface connects the wake-up input module and the wake-up output module, such as Figure 7 As shown, the wake-up input module wakes up the DC-DC converter via the IO wake-up interface; as Figure 8 As shown, the wake-up output module wakes up other vehicle devices through the IO wake-up interface.

[0022] like Figure 9 As shown, the communication module is connected to the microcontroller module and is used to realize information interaction with external devices. It supports vehicle protocols such as CAN / LIN, realizes data interaction with devices such as BMS and OBC, and supports remote diagnosis and parameter configuration.

[0023] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made to the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention. Although preferred embodiments of the present invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention. Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and variations.

Claims

1. A vehicle-mounted DC-DC system integrating 48V and 12V, characterized in that, It includes a power stage circuit module, a microcontroller module, a drive circuit module, an auxiliary power supply module, an output reverse current protection module, a sampling circuit module, a communication module, a protection circuit module, and an IO wake-up interface; the power stage circuit module includes a high-voltage input module, an EMI filter module, a full-bridge circuit module, and a dual-branch output module; the dual-branch output module includes a 48V output branch and a 12V output branch; the 48V output branch includes an output winding 1, a full-bridge rectifier module, a reverse current protection module 1, an output protection module 1, and a 48V output module; the 12V output branch includes an output winding 2, a full-bridge rectifier module, a reverse current protection module 2, an output protection module 2, and a 12V output module.

2. The 48V and 12V integrated vehicle DC-DC system as described in claim 1, characterized in that, The EMI filtering module includes an input EMI filtering module and an output EMI filtering module; the input EMI filtering module is connected to the high-voltage input module, and the output EMI filtering module includes EMI filtering module 1 and EMI filtering module 2; EMI filtering module 1 is located in the 48V output branch, and EMI filtering module 2 is located in the 12V output branch.

3. The 48V and 12V integrated vehicle DC-DC system as described in claim 1, characterized in that, The backflow prevention module 1 and the backflow prevention module 2 are each composed of a set of back-to-back power switching transistors and a driver. The driver is used to drive the back-to-back power switching transistors to turn on and off, and is controlled by the microcontroller module.

4. The 48V and 12V integrated vehicle DC-DC system as described in claim 1, characterized in that, The anti-backflow module 1 and anti-backflow module 2 are each composed of a set of back-to-back diodes, used to prevent current from the external vehicle battery from being injected into the power stage circuit module.

5. The 48V and 12V integrated vehicle DC-DC system as described in claim 1, characterized in that, The EMI filter module circuit is equipped with a reverse connection protection circuit module at the front end to protect the vehicle DC-DC system from damage when the input high voltage is reversed.

6. The 48V and 12V integrated vehicle DC-DC system as described in claim 1, characterized in that, The 48V output branch is a full-bridge structure; the 12V output branch is a half-bridge structure with a center tap.

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