Vehicle-mounted low-voltage composite power supply

Abstract

The invention belongs to the technical field of automobile power supplies, and discloses a vehicle-mounted low-voltage composite power supply which comprises three branches, a vehicle-mounted main power supply is divided into the three branches after being converted by a high-voltage DCDC conversion module, the first branch supplies power to a vehicle-mounted battery, and the second branch supplies power to a super capacitor, a KL30 load and a safety load through a low-voltage DCDC conversion module. And the third branch supplies power to the steer-by-wire load, and meanwhile, the supercapacitor supplies power to the safety load in a backup manner. The low-voltage composite power supply structure is high in integration level and clear in architecture, a 12V battery, a 12V standby battery and a super-capacity pre-charging module can be omitted, the cost is greatly reduced, the power supply effect is good, and the industrial production requirement is met.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile power supplies, and in particular relates to a vehicle-mounted low-voltage composite power supply. Background Art

[0002] With the introduction of automobile wire-controlled steering, fully automatic suspension, active stabilizer bar, etc., which bring more benefits to intelligent driving, comfort and convenience, the 48V electrical system came into being. However, due to the large variety of 12V electronic components in the whole vehicle and the long period of resistance to upgrading to 48V power supply products, it has to exist for a long period of time. There are two low-voltage systems, 12V and 48V, in the same smart vehicle. In order to maintain the stability of the low-voltage board network, in addition to the conventional 12V battery voltage-stabilized 12V board network, it is also necessary to add a 48V battery voltage-stabilized 48V board network, which has a very complex structure. In addition, the current of these load feedback energy is large, in pulse form, and the frequency is uncertain. The whole vehicle pursues low-temperature performance. At present, the performance of the battery is gradually "frozen" at low temperatures. Supercapacitors have high power characteristics and work in the full temperature range. The combination of battery and supercapacitor has become the best partner to solve this problem. In addition, the safety load on the whole vehicle also requires an additional 12V battery to power it, so we need to expand our thinking and seek a better solution for the vehicle's low-voltage power supply. Summary of the invention

[0003] The present invention provides a vehicle-mounted low-voltage composite power supply, which solves the technical problems in the prior art of requiring two sets of low-voltage systems for power supply, resulting in a complex circuit structure.

[0004] The present invention can be achieved through the following technical solutions:

[0005] A vehicle-mounted low-voltage composite power supply includes three branches. The vehicle-mounted total power supply is divided into three branches after being converted by a high-voltage DCDC conversion module. The first branch supplies power to the vehicle-mounted battery, the second branch supplies power to a supercapacitor, a KL30 load and a safety load through the low-voltage DCDC conversion module, and the third branch supplies power to a wire-controlled steering load. At the same time, the supercapacitor independently supplies power to the safety load.

[0006] Furthermore, in the second branch, the low voltage DCDC conversion module is directly connected to the KL30 load, and is respectively connected to the super capacitor and the safety load through the charge and discharge switch, and the super capacitor is directly connected to the safety load.

[0007] Furthermore, the charge and discharge switch adopts a MOS tube structure with a body diode.

[0008] Furthermore, the high-voltage DCDC conversion module is connected to three branches via an input switch, the first branch is connected to the vehicle battery via a charge and discharge module, and the third branch is connected to the wire-controlled steering load via a load switch.

[0009] Furthermore, the high-voltage DCDC conversion module is used to convert a 48V power supply, the low-voltage DCDC conversion module is used to convert a 12V power supply, the input switch and the load switch are both MOS tubes with body diodes, and the charge and discharge module adopts a small current charge and discharge circuit structure.

[0010] An operation method based on the above-mentioned vehicle-mounted low-voltage composite power supply is as follows:

[0011] 1) During debugging, the low-voltage DCDC conversion module is controlled to be enabled, and the supercapacitor is charged by the vehicle battery through the low-voltage DCDC conversion module and the body diode of the charge and discharge switch, so that the voltage output by the supercapacitor and the low-voltage DCDC conversion module maintain the same voltage;

[0012] 2) Load the debugged low-voltage composite power supply onto the vehicle.

[0013] ①The vehicle-mounted battery supplies power to the KL30 load normally;

[0014] ② The on-board battery supplies power to the supercapacitor and safety loads normally, and the supercapacitor also serves as an independent backup power supply for the safety load;

[0015] 3) When the vehicle is in ACC mode,

[0016] ① Close the load switch and the main circuit of the charge and discharge module, supply power to the wire-controlled steering load through the vehicle battery, close the input switch, and prepare for the power input converted from the vehicle main power supply;

[0017] 4) When the vehicle is IGon,

[0018] ① The electric energy converted by the high-voltage DCDC conversion module and the on-board battery jointly power the wire-controlled steering load;

[0019] ② The electric energy converted by the high-voltage DCDC conversion module and the on-board battery are used together through the low-voltage DCDC conversion module to supply power to the KL30 load, supercapacitor, and safety load;

[0020] ③ Close the charge and discharge switch, and the supercapacitor will supply power to the KL30 load and the safety load at the same time;

[0021] 5) Energy recovery,

[0022] ①When the KL30 load is fed with power, the recovered energy is absorbed by the supercapacitor through the charge and discharge switch;

[0023] ② When the wire-controlled steering load is fed with power, the recovered energy is absorbed in two ways. One way passes through the low-voltage DCDC conversion module and the charge and discharge switch and enters the supercapacitor to be recovered. The other way passes through the small current charge and discharge module and enters the on-board battery to be recovered, so as to stabilize the grid voltage.

[0024] 6) When the vehicle is IGoff,

[0025] ①KL30 load recovers the normal power supply from the on-board battery through the low-voltage DCDC conversion module;

[0026] ② Disconnect the charge and discharge switch, and through the body diode of the charge and discharge switch, the safety load recovers the normal power supply from the on-board battery through the output of the low-voltage DCDC conversion module, and at the same time recovers the independent backup power supply state from the supercapacitor.

[0027] ③Disconnect the load switch and the steering-by-wire load will have no power supply.

[0028] The beneficial technical effects of the present invention are as follows:

[0029] 1. The 48V vehicle battery and the 12V supercapacitor are combined to form a low-voltage composite power supply on the vehicle, which can provide all the low-voltage power supplies required by the vehicle, including 48V, 12V and backup power required for safety loads. Through clever design, the supercapacitor can be reused as a backup power supply for safety loads, or even as an independent backup power supply when the vehicle is not in operation. It is fully functional, meets the power supply needs of existing smart vehicles, and has good practicality.

[0030] 2. Make full use of the high-rate charge and discharge performance of the supercapacitor within the full temperature range to absorb and reuse the power feed of the KL30 load, and use it together with the 48V on-board battery to absorb and reuse the power feed of the wire-controlled steering load, so as to make up for the loss of the battery's charge and discharge power characteristics at low temperatures, so that one supercapacitor component can complete the voltage stabilization of both the 12V and 48V power grids;

[0031] The low-voltage composite power supply structure of the present invention has high integration and clear architecture, and can save 12V batteries, 12V backup batteries and super-capacity pre-charging modules, greatly reducing costs, having good power supply effects, and meeting the needs of industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a block diagram of the overall circuit structure of the present invention. DETAILED DESCRIPTION

[0033] The present invention is further explained below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise defined, the technical terms or scientific terms used herein should be understood by a person with ordinary skills in the technical field to which the present invention belongs. All the values ​​from the lowest value to the highest value listed herein refer to all the values ​​obtained by incrementing the lowest value to the highest value by one unit when the difference between the lowest value and the highest value is more than two units.

[0034] like Figure 1 As shown, an embodiment of the present invention provides a vehicle-mounted low-voltage composite power supply, including three branches. The vehicle-mounted total power supply is divided into three branches after being converted by a high-voltage DCDC conversion module. The first branch supplies power to the vehicle-mounted battery, the second branch supplies power to the supercapacitor, the KL30 load and the safety load through a low-voltage DCDC conversion module, and the third branch supplies power to the wire-controlled steering load, while the supercapacitor supplies power to the safety load independently. In this way, the low-voltage composite power supply of the present invention can provide a stable 48V power supply and energy recovery for a 48V load at the same time, and provide a stable 12V power supply and energy recovery for a 12V load, and provide the necessary power supply output for a 12V safety load, which greatly reduces unnecessary redundant structures, has a high degree of integration, can meet vehicle-mounted use, has a good power supply effect, and can meet the needs of industrial mass production.

[0035] Specifically, the vehicle-mounted low-voltage composite power supply of the present invention includes a high-voltage DCDC conversion module A, an input switch 1, an on-board battery 5, a charging and discharging module 2, a low-voltage DCDC conversion module 6, a supercapacitor 8, a charging and discharging switch 7, and a load switch 9, wherein the charging and discharging module 2 adopts a low-current charging and discharging module 3 structure controlled by a MOS tube 4 with a body diode, including a MOS tube, a driver, and a current limiting resistor; the charging and discharging switch 7, the input switch 1, and the load switch 9 are all configured as a MOS tube structure with a body diode controlled by a driver, and its driver can adopt a high-side driver such as TPS48000QDGXRQ1, and the supercapacitor 8 is configured as a 330F6s supercapacitor module with a normal operating voltage range of 10.8V-16.2V and 55F.

[0036] One input is set to a 48V power supply converted from the whole vehicle through the high-voltage DCDC conversion module A, and three outputs are set, including a 48V load B output for wire-controlled steering, a 12V load C output to power the KL30 load of the whole vehicle, and a 12V safety load D output for collision unlocking.

[0037] One end of the input switch of the vehicle's main power supply is connected to the 48V power supply converted from the high-voltage DCDC conversion module A of the whole vehicle, and the other end is divided into three branches in sequence. The first branch is connected to the charging and discharging module 2 and the vehicle battery in sequence; the second branch is connected to the KL30 load B and the safety load C through the 12V power supply converted by the low-voltage DCDC conversion module 6; the third branch is directly connected to the 48V load such as the wire-controlled steering load, and the disconnection is controlled by the load switch 9; the second branch is divided into two branches in sequence through the other end of the low-voltage DCDC conversion module 6, one branch is connected to the 12V load such as the KL30 load B, and the other branch is connected to the safety load 9 and the supercapacitor 8 through the charging and discharging switch 7.

[0038] At the same time, the present invention also provides an operation method based on the above-mentioned vehicle-mounted low-voltage composite power supply, which is as follows:

[0039] 1) During debugging, the low-voltage DCDC conversion module 6 is controlled to be enabled, and the supercapacitor 8 is charged by the vehicle battery through the low-voltage DCDC conversion module 6 and the body diode of the charge-discharge switch 7, so that the voltage output by the supercapacitor 8 and the low-voltage DCDC conversion module 6 maintain the same voltage;

[0040] 2) Load the debugged low-voltage composite power supply onto the vehicle.

[0041] ① The vehicle-mounted battery 5 supplies power to the KL30 load B normally;

[0042] ② The vehicle-mounted battery 5 supplies power to the supercapacitor 8 and the safety load 9 normally, and the supercapacitor 8 also serves as an independent backup power supply for the safety load D;

[0043] 3) When the vehicle is in ACC mode,

[0044] ① Close the load switch 9 and the main circuit of the charge-discharge module 2, supply power to the wire-controlled steering load B through the vehicle battery 5, close the input switch, and prepare for the input of electric energy converted from the vehicle main power supply;

[0045] 4) When the vehicle is IGon,

[0046] ① The electric energy converted by the high-voltage DCDC conversion module A and the on-board battery 5 together supply power to the wire-controlled steering load B;

[0047] ② The electric energy converted by the high-voltage DCDC conversion module A and the vehicle battery 5 are used together through the low-voltage DCDC conversion module 6 to supply power to the KL30 load C, the supercapacitor 8, and the safety load D;

[0048] ③ Close the charge and discharge switch 7, and the super capacitor 8 supplies power to the KL30 load C and the safety load D at the same time;

[0049] 5) Energy recovery,

[0050] ① When the KL30 load C is fed with power, the recovered energy is absorbed by the supercapacitor through the charge and discharge switch 7;

[0051] ② When the wire-controlled steering load B is fed with power, the recovered energy is absorbed in two ways. One way passes through the low-voltage DCDC conversion module 6 and the charge-discharge switch 7 and enters the supercapacitor 8 to be recovered. The other way passes through the charge-discharge module 2 and enters the vehicle battery 5 to be recovered, so as to stabilize the grid voltage.

[0052] 6) When the vehicle is IGoff,

[0053] ① KL30 load B recovers the power from the vehicle battery 5 output through the low voltage DCDC conversion module 6 to supply power normally;

[0054] ② The charge and discharge switch 7 is turned off, and the safety load D recovers the normal power supply from the vehicle battery 5 through the body diode of the charge and discharge switch 7 via the electric energy output by the low-voltage DCDC conversion module 6, and at the same time recovers the independent backup power supply state from the supercapacitor 8.

[0055] ③ Disconnect the load switch 9, and the steering-by-wire load B has no power supply.

[0056] Although specific embodiments of the present invention are described above, those skilled in the art should understand that these are merely examples and that various changes or modifications may be made to these embodiments without departing from the principles and essence of the present invention. Therefore, the scope of protection of the present invention is limited by the appended claims.

Claims

1. A vehicle-mounted low-voltage composite power supply, characterized in that: It includes three branches. The total vehicle power supply is divided into three branches after conversion by the high-voltage DCDC conversion module. The first branch supplies power to the vehicle battery, the second branch supplies power to the supercapacitor, KL30 load and safety load through the low-voltage DCDC conversion module, and the third branch supplies power to the wire-controlled steering load. At the same time, the supercapacitor provides backup power for the safety load.

2. The vehicle-mounted low-voltage composite power supply according to claim 1, characterized in that: In the second branch, the low voltage DCDC conversion module is directly connected to the KL30 load, and is respectively connected to the super capacitor and the safety load through the charge and discharge switch, and the super capacitor is directly connected to the safety load.

3. The vehicle-mounted low-voltage composite power supply according to claim 2, characterized in that: The charge and discharge switch adopts a MOS tube structure with a body diode.

4. The vehicle-mounted low-voltage composite power supply according to claim 1, characterized in that: The high-voltage DCDC conversion module is connected to three branches respectively via an input switch, the first branch is connected to the vehicle battery via a charge and discharge module, and the third branch is connected to the wire-controlled steering load via a load switch.

5. The vehicle-mounted low-voltage composite power supply according to claim 4, characterized in that: The high-voltage DCDC conversion module is used to convert a 48V power supply, the low-voltage DCDC conversion module is used to convert a 12V power supply, the input switch and the load switch are both MOS tubes with body diodes, and the charge and discharge module adopts a small current charge and discharge circuit structure.

6. An operating method based on the vehicle-mounted low-voltage composite power supply according to claim 1, characterized in that: 1) During debugging, the low-voltage DCDC conversion module is controlled to be enabled, and the supercapacitor is charged by the vehicle battery through the low-voltage DCDC conversion module and the body diode of the charge and discharge switch, so that the voltage output by the supercapacitor and the low-voltage DCDC conversion module maintain the same voltage; 2) Load the debugged low-voltage composite power supply onto the vehicle. ①The vehicle-mounted battery supplies power to the KL30 load normally; ② The on-board battery supplies power to the supercapacitor and safety loads normally, and the supercapacitor also serves as an independent backup power supply for the safety load; 3) When the vehicle is in ACC mode, ① Close the load switch and the main circuit of the charge and discharge module, supply power to the wire-controlled steering load through the vehicle battery, close the input switch, and prepare for the power input converted from the vehicle main power supply; 4) When the vehicle is IGon, ① The electric energy converted by the high-voltage DCDC conversion module and the on-board battery jointly power the wire-controlled steering load; ② The electric energy converted by the high-voltage DCDC conversion module and the on-board battery are used together through the low-voltage DCDC conversion module to supply power to the KL30 load, supercapacitor, and safety load; ③ Close the charge and discharge switch, and the supercapacitor will supply power to the KL30 load and the safety load at the same time; 5) Energy recovery, ①When the KL30 load is fed with power, the recovered energy is absorbed by the supercapacitor through the charge and discharge switch; ② When the wire-controlled steering load is fed with power, the recovered energy is absorbed in two ways. One way passes through the low-voltage DCDC conversion module and the charge and discharge switch and enters the supercapacitor to be recovered. The other way passes through the small current charge and discharge module and enters the on-board battery to be recovered, ensuring the stability of the grid voltage. 6) When the vehicle is IGoff, ①KL30 load recovers the normal power supply from the on-board battery through the low-voltage DCDC conversion module; ② Disconnect the charge and discharge switch, and through the body diode of the charge and discharge switch, the safety load recovers the normal power supply from the on-board battery through the output of the low-voltage DCDC conversion module, and at the same time recovers the independent backup power supply state from the supercapacitor. ③Disconnect the load switch and the steering-by-wire load will have no power supply.

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