CN111591168A - Low-temperature cold start method and device for hybrid vehicle, storage medium and equipment - Google Patents

Abstract

The invention discloses a low-temperature cold starting device, method, storage medium and equipment of a hybrid vehicle, wherein the device comprises: the bidirectional voltage conversion module is used for converting low voltage of first voltage output by the low-voltage vehicle-mounted power supply into high voltage of second voltage in a reverse working state or converting high voltage of second voltage output by the high-voltage power battery into low voltage of first voltage in a forward working state; the temperature judging module is used for responding to the starting signal to judge whether the ambient temperature of the vehicle is lower than a preset temperature or not; the state setting module is used for setting the bidirectional voltage conversion module to be in a reverse working state when the ambient temperature of the vehicle is lower than a preset temperature; and the first power supply connection module is used for connecting the bidirectional voltage conversion module and the high-voltage power battery with the starting motor when the bidirectional voltage conversion module is in a reverse working state. The invention can make up the defect of insufficient low-temperature discharge power of the high-voltage lithium battery pack to a certain extent.

Description

Hybrid vehicle low temperature cold start method, device, storage medium and device

technical field

The present invention relates to the technical field of vehicles, in particular to a low-temperature cold start method, device, storage medium and device for a hybrid vehicle.

Background technique

In hybrid electric vehicles, based on cost considerations, the engine generally cancels the starter, the engine is started by the starter motor (the generator in the hybrid vehicle), and the starter motor is powered by the high-voltage lithium battery pack. The chemical characteristics of the lithium battery determine that its discharge power decreases with the decrease in temperature. At low ambient temperature (such as below -30°C), the output power of the lithium battery pack is insufficient, and the starter motor may not be driven, so the engine cannot be started. The situation affects the customer's car experience.

At present, there are two main technologies for improving the cold start performance of lithium-ion batteries: one is to add a heatable device around the lithium-ion battery, and the temperature of the lithium-ion battery is increased by physical heating. device, while increasing the space and cost, the heating time is long and the efficiency is low; the other is to add a short circuit on the basis of the existing hybrid vehicle starting system, this method will greatly improve the chemical activity of the cathode material As a result, the cathode material reacts rapidly with the electrolyte, producing a large amount of gas, and the pressure and temperature inside the lithium-ion battery rapidly increase, causing the battery to explode, which is not conducive to ensuring the safety and service life of the battery. Therefore, it is necessary to improve the existing technical solutions to solve the difficult problem of low temperature cold start of hybrid electric vehicles.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, a first aspect of the present invention provides a low temperature cold start device for a hybrid vehicle, comprising the following modules:

The bidirectional voltage conversion module is used to convert the low-voltage electricity of the first voltage outputted by the low-voltage vehicle power supply into the high-voltage electricity of the second voltage in the reverse working state, or convert the output of the high-voltage power battery in the forward working state. Converting high-voltage electricity of the second voltage into low-voltage electricity of the first voltage;

a temperature judging module for judging whether the ambient temperature of the vehicle is lower than a preset temperature in response to the start signal;

a state setting module for setting the bidirectional voltage conversion module to a reverse working state when the ambient temperature of the vehicle is lower than a preset temperature;

a first power connection module, configured to connect both the bidirectional voltage conversion module and the high-voltage power battery to the starter motor when the bidirectional voltage conversion module is in a reverse working state;

Wherein, the low-voltage vehicle power supply is connected to one end of the bidirectional voltage conversion module, the other end of the bidirectional voltage conversion module is connected to the starter motor, and the high-voltage power battery is connected to the starter motor.

Further, the state setting module is further configured to set the bidirectional voltage conversion module to a forward working state when the ambient temperature of the vehicle is not lower than a preset temperature.

Further, it also includes:

a pre-charging module, used for setting the bidirectional voltage conversion module to a reverse working state in response to a high-voltage signal on the vehicle, and pre-charging the high-voltage load capacitor;

a voltage comparison module for judging whether the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

The high-voltage power-on module is used to control the high-voltage power on the vehicle when the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

The second power connection module is used to connect the high-voltage power battery and the starter motor after the high-voltage power on the vehicle is completed.

A second aspect of the present invention provides a low-temperature cold start method for a hybrid vehicle, using the above-mentioned low-temperature cold start device for a hybrid vehicle, and the method includes the following steps:

In response to the vehicle start signal, determine whether the ambient temperature of the vehicle is lower than a preset temperature;

When the ambient temperature of the vehicle is lower than the preset temperature, setting the bidirectional voltage conversion module to a reverse working state;

When the bidirectional voltage conversion module is in a reverse working state, both the bidirectional voltage conversion module and the high-voltage power battery are connected to the starter motor.

Further, after judging whether the ambient temperature of the vehicle is lower than the preset temperature, the method further includes:

When the ambient temperature of the vehicle is not lower than the preset temperature, the bidirectional voltage conversion module is set to a forward working state.

Further, it also includes:

In response to the high-voltage signal on the vehicle, the bidirectional voltage conversion module is set to a reverse working state, and the high-voltage load capacitor is precharged;

Determine whether the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

When the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery, control the high-voltage power on the vehicle;

After the high-voltage power on the whole vehicle is completed, connect the high-voltage power battery to the starter motor.

Further, it also includes:

After the vehicle is started, the bidirectional voltage conversion module is set to a forward working state.

Further, the bidirectional voltage conversion module includes a bidirectional DC/DC converter.

A third aspect of the present invention provides a computer-readable storage medium, the storage medium stores at least one instruction, at least one piece of program, code set or instruction set, the at least one instruction, the at least one piece of program, the at least one piece of program, the The code set or the instruction set is loaded and executed by the processor to realize the above-mentioned low temperature cold start method of the hybrid electric vehicle.

A fourth aspect of the present invention provides a device, the device includes a processor and a memory, and the memory stores at least one instruction, at least one segment of a program, a code set or an instruction set, the at least one instruction, the at least one segment of The program, the code set or the instruction set is loaded and executed by the processor to implement the above-mentioned method for low temperature cold start of a hybrid electric vehicle.

Implementing the present invention has the following beneficial effects:

The invention adopts a bidirectional voltage conversion module to boost the low-voltage power output by the low-voltage vehicle power supply, so that in a low temperature environment, the low-voltage vehicle-mounted power supply and the high-voltage power battery act as an energy system to drive the engine starter motor, which can compensate for the high-voltage lithium to a certain extent. Disadvantages of insufficient low-temperature discharge power of battery packs. Besides, the present invention also has a pre-charging function, which can cancel the pre-charging circuit in the original high-voltage system and reduce the hardware cost of the high-voltage circuit.

Additional aspects and advantages of the present invention will be set forth, in part, from the following description, and in part will be apparent from the following description, or may be learned by practice of the invention.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a structural block diagram of a low-temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention;

2 is a structural block diagram of a low-temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention;

3 is a circuit diagram of a low temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention;

4 is a working principle diagram of a low temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention;

5 is a flowchart of a low-temperature cold start method for a hybrid vehicle provided by an embodiment of the present invention;

FIG. 6 is a flowchart of a high-voltage loop precharging provided by an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Examples of such embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout.

Example

FIG. 1 is a structural block diagram of a low temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention. Please refer to FIG. 1 . A low temperature cold start device for a hybrid vehicle disclosed in an embodiment of the present invention includes the following modules:

The bidirectional voltage conversion module 101 is used to convert the low-voltage electricity of the first voltage output by the low-voltage vehicle power supply into the high-voltage electricity of the second voltage in the reverse working state, or convert the first voltage outputted by the high-voltage power battery in the forward working state. The high-voltage electricity of the second voltage is converted into the low-voltage electricity of the first voltage;

Specifically, the low-voltage vehicle power supply is a 12V vehicle battery for outputting 12V direct current.

Specifically, the high-voltage power battery can output high-voltage electricity, and the high-voltage power battery includes a high-voltage lithium battery.

Optionally, the value of the second voltage is between 200V-400V.

Optionally, the first voltage value may be 12V, 24V or other low voltage values set according to actual needs; in an example, when the hybrid vehicle is a sedan, the corresponding first voltage value may be set to 12V; in an example , when the hybrid vehicle is a truck, a bus, or the like, the corresponding first voltage value may be set to 24V. It should be pointed out that the above examples are only used to illustrate the value of the first voltage, and should not be regarded as a limitation of the embodiments of the present invention. The value of the first voltage may also be set to other values according to actual conditions.

In a preferred embodiment, the bidirectional voltage conversion module 101 may be a bidirectional DC/DC converter. A bidirectional DC/DC converter is used to replace the one-way DC/DC converter in the original hybrid vehicle system. When the engine is cold started at low temperature, in addition to the high-voltage lithium battery pack providing high-voltage power to the starter motor, the 12V on-board battery passes through the bidirectional DC/DC/DC converter. The DC converter converts to high voltage, and then also provides high voltage power to the starter motor, so that the short-term power superimposed by the two batteries can make up for the insufficient low temperature output power of a single lithium battery pack. Insufficient to start the engine problem.

Preferably, the bidirectional voltage conversion module 101 adopts a full-bridge DC/DC converter, and the full-bridge DC/DC converter has the advantages of large output power and high efficiency.

a temperature determination module 102, configured to determine whether the ambient temperature of the vehicle is lower than a preset temperature in response to the start signal;

In one embodiment, the preset temperature value is -25°C; in one embodiment, the preset temperature value is -30°C; in one embodiment, the preset temperature value is -35°C; it should be pointed out However, the above examples are only used for illustration, and those skilled in the art can also use other temperature values as the preset temperature values according to actual needs.

a state setting module 103, configured to set the bidirectional voltage conversion module 101 to a reverse working state when the ambient temperature of the vehicle is lower than a preset temperature;

The first power connection module 104 is used to connect both the bidirectional voltage conversion module 101 and the high-voltage power battery to the starter motor when the bidirectional voltage conversion module 101 is in a reverse working state;

The low-voltage vehicle power supply is connected to one end of the bidirectional voltage conversion module 101, the other end of the bidirectional voltage conversion module 101 is connected to the starter motor, and the high-voltage power battery is connected to the starter motor.

Further, the state setting module 103 is further configured to set the bidirectional voltage conversion module 101 to a forward working state when the ambient temperature of the vehicle is not lower than the preset temperature.

In the prior art, in order to protect the high-voltage relay and prevent the high-voltage relay from sticking, a pre-charging circuit generally needs to be added to the output circuit of the high-voltage power battery. The pre-charging circuit includes a pre-charging resistor, a pre-charging relay and a corresponding control circuit. The principle is to pre-charge the capacitive load in the high-voltage load circuit before the high-voltage relay is pulled in. When the load voltage is pre-charged to close to the battery bus voltage, the high-voltage relay is pulled in, so that the high-voltage relay will not produce production when the high-voltage relay is pulled in. high current, thus protecting the high voltage relay contacts.

In the embodiment of the present invention, the bidirectional voltage conversion module 101 can also be used to precharge the high-voltage circuit, that is, before the high voltage is applied to the whole vehicle, the low-voltage on-board power supply is boosted by the bidirectional voltage conversion module 101 to precharge the high-voltage load capacitor. After the high-voltage relay is closed, the pre-charging circuit of the original high-voltage system can be cancelled, and the hardware cost of the high-voltage circuit can be reduced.

FIG. 2 is a structural block diagram of a low-temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention. Please refer to FIG. 2. In one embodiment, the device further includes:

The pre-charging module 105 is used to set the bidirectional voltage conversion module 201 to the reverse working state in response to the high-voltage signal on the vehicle, and pre-charge the high-voltage load capacitor;

The voltage comparison module 106 is used for judging whether the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

The high-voltage power-on module 107 is used to control the high-voltage power on the vehicle when the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

The second power connection module 108 is used to connect the high-voltage power battery and the starter motor after the high-voltage power on the vehicle is completed.

3 is a circuit diagram of a low temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention, and FIG. 4 is a working principle diagram of a low temperature cold start device for a hybrid vehicle provided by an embodiment of the present invention. Please refer to FIG. 3 and FIG. 4. In a specific embodiment, the device includes the following components: power battery system, bidirectional DC/DC converter, low-voltage on-board power supply, low-voltage load, dual motor controller (PCM), engine, generator (and start-up) Motor), drive motor, vehicle controller, vehicle CAN bus, etc. Among them, the generator (and starter motor) is used as the engine starter motor when the engine is started. Specifically, the power battery system shown in FIG. 3 includes a high-voltage power battery, which is a high-voltage lithium battery; specifically, the low-voltage vehicle power supply shown in FIG. 3 includes a 12V battery, which may be a lead-acid battery.

Please continue to refer to Figure 4. When the high-voltage power battery supplies power to the 12V battery and the low-voltage load, the bidirectional DC/DC converter works in the forward working state. At this time, Q1, Q2, Q3, and Q4 are alternately turned on and off at high frequency. At this time, the transformer T Q5 and Q6 on the other side are off and do not work. The diodes connected in parallel on Q5 and Q6 rectify the AC voltage on the secondary side of the transformer, and then filter through capacitors C5 and C6 to provide DC 12V to the 12V battery and low-voltage load. Q1～ Q6 is controlled by a bidirectional DC/DC control circuit.

Please continue to refer to Figure 4. When the 12V battery outputs high-voltage power in reverse through the bidirectional DC/DC converter, the bidirectional DC/DC converter works in the reverse working state, in which Q5 and Q6 are alternately turned on and off at high frequency. At this time, the transformer T is another Q1, Q2, Q3, and Q4 on one side are in a cut-off state, and the diodes connected in parallel with Q1 to Q4 form a full-bridge rectifier circuit, which rectifies the AC voltage on the high-voltage side of the transformer, and then is filtered by capacitors C2 and C3 to provide the high-voltage circuit. High voltage, Q1~Q6 are controlled by bidirectional DC/DC control circuit.

Please continue to refer to FIG. 4 , specifically, K1 in the high-voltage power battery system is a high-voltage positive relay, K3 is a high-voltage negative relay, and the positive relay K1 is connected in parallel with the relay K2 and the diode D1. The following describes the high-voltage load capacitor precharging process, the engine cold start process at room temperature, and the engine cold start process at low temperature according to the embodiment of the present invention in turn with reference to FIG. 4 .

High voltage load capacitor precharge process:

After the bidirectional DC/DC converter receives the high-voltage signal on the vehicle, it converts the 12V low voltage into high-voltage power and pre-charges the high-voltage load capacitor C1 (equivalent capacitor). When the output voltage is close, the pre-charging function is completed, and then the high-voltage relays K1 and K3 are closed (K2 is always disconnected at this time) to complete the high-voltage electricity process on the vehicle.

The closeness between the charging voltage of the high-voltage load capacitor C1 and the output voltage of the high-voltage power battery specifically means that the difference between the charging voltage of the high-voltage load capacitor C1 and the output voltage of the high-voltage power battery is within a preset pressure difference range, for example, the voltage difference between the two is 1V, the preset maximum voltage difference is 2V, the charging voltage of the high-voltage load capacitor C1 is considered to be close to the output voltage of the high-voltage power battery; for example, if the voltage difference between the two is 3V, and the preset maximum voltage difference is 2V, then the high-voltage load capacitor C1 is not considered to be The charging voltage is close to the output voltage of the high-voltage power battery.

It should be noted that the above example is only used to illustrate "the charging voltage of the high-voltage load capacitor C1 is close to the output voltage of the high-voltage power battery", and should not be regarded as a limitation on the embodiments of the present invention. In the specific application process, the preset pressure difference The range can be calibrated and set according to the actual situation.

Engine cold start process at room temperature:

In the normal temperature environment, the high-voltage power battery has a large output power and can normally drive the starter motor to complete the engine start. The working process is as follows: After receiving the start signal, the bidirectional DC/DC converter first pre-charges the high-voltage circuit, and the high-voltage relays K1 and K3 Pull in (K2 is always disconnected at this time), the whole vehicle completes the high voltage, the high voltage power battery supplies high voltage power to the motor controller 1, drives the starter motor, and completes the normal start of the engine.

Engine low temperature cold start process:

In a low temperature environment, the output power of the high-voltage power battery is not enough to drive the starter motor. At this time, the bidirectional DC/DC converter works in the reverse working state of low voltage to high voltage. The 12V battery supplies power to the starter motor through the bidirectional DC/DC converter. , K2 and K3 are pulled in (K1 is disconnected at this time), and the high-voltage power battery also supplies power to the starter motor. After superimposing the output power of the 12V battery, the high-voltage power battery can complete the starter motor drive, thereby realizing the low-temperature cold start of the engine. After the low temperature cold start is completed, K1 is turned on, K2 is turned off (K3 is turned on at this time), the bidirectional DC/DC converter switches to the normal forward working state, and supplies power to the low-voltage load and the 12V battery.

The relevant voltage and current real-time information of the high-voltage power battery, the high-voltage load and the bidirectional DC/DC converter is exchanged with the vehicle controller through the CAN bus. The vehicle controller sends the relevant command information to the bidirectional DC/DC converter through real-time judgment. It is used to control the working state of the bidirectional DC/DC converter and the pull-in and disconnection states of the high-voltage relays K1, K2 and K3 of the high-voltage power battery, so as to complete the corresponding functions.

FIG. 5 is a flowchart of a low-temperature cold start method for a hybrid vehicle provided by an embodiment of the present invention. Please refer to FIG. 5 . An embodiment of the present invention also discloses a low-temperature cold start method for a hybrid vehicle, using the above-mentioned hybrid vehicle. A low temperature cold start device, the method includes the following steps:

S201: In response to a vehicle start signal, determine whether the ambient temperature of the vehicle is lower than a preset temperature;

In one embodiment, the preset temperature value is -25°C; in one embodiment, the preset temperature value is -30°C; in one embodiment, the preset temperature value is -35°C; it should be pointed out However, the above examples are only used for illustration, and those skilled in the art can also use other temperature values as the preset temperature values according to actual needs.

S202: when the ambient temperature of the vehicle is lower than the preset temperature, set the bidirectional voltage conversion module to a reverse working state;

Specifically, the bidirectional voltage conversion module can convert the low-voltage power of the first voltage output by the low-voltage vehicle power supply into the high-voltage power of the second voltage in the reverse working state, or convert the first voltage outputted by the high-voltage power battery in the forward working state. The high voltage of the second voltage is converted into the low voltage of the first voltage.

Optionally, the value of the second voltage is between 200V-400V.

Optionally, the first voltage value may be 12V, 24V or other low voltage values set according to actual needs; in an example, when the hybrid vehicle is a sedan, the corresponding first voltage value may be set to 12V; in an example , when the hybrid vehicle is a truck, a bus, or the like, the corresponding first voltage value may be set to 24V. It should be pointed out that the above examples are only used to illustrate the value of the first voltage, and should not be regarded as a limitation of the embodiments of the present invention. The value of the first voltage may also be set to other values according to actual conditions.

Preferably, the bidirectional voltage conversion module may be a bidirectional DC/DC converter;

Preferably, the bidirectional voltage conversion module adopts a full-bridge DC/DC converter, and the full-bridge DC/DC converter has the advantages of large output power and high efficiency.

S203: When the bidirectional voltage conversion module is in a reverse working state, connect both the bidirectional voltage conversion module and the high-voltage power battery to the starter motor.

Specifically, the low-voltage vehicle power supply is a 12V vehicle battery for outputting 12V direct current.

Specifically, the high-voltage power battery can output high-voltage electricity, and the high-voltage power battery includes a high-voltage lithium battery.

A bidirectional DC/DC converter is used to replace the one-way DC/DC converter in the original hybrid vehicle system. When the engine is cold started at low temperature, in addition to the high-voltage lithium battery pack providing high-voltage power to the starter motor, the 12V on-board battery passes through the bidirectional DC/DC/DC converter. The DC converter converts to high voltage, and then also provides high voltage power to the starter motor, so that the short-term power superimposed by the two batteries can make up for the insufficient low temperature output power of a single lithium battery pack. Insufficient to start the engine problem.

The vehicle controller performs real-time processing on the collected external ambient temperature, engine starting signal, and high-voltage pre-charging starting signal, makes a comprehensive judgment based on the collected signals, and controls the bidirectional DC/DC converter, high-voltage power battery, and motor through the CAN bus. The U control unit of the controller and other components sends real-time instructions, and after receiving the instructions from the vehicle controller, the bidirectional DC/DC converter, high-voltage power battery, motor controller and other components perform corresponding actions to complete the pre-charging and engine start work.

In the prior art, in order to protect the high-voltage relay and prevent the high-voltage relay from sticking, a pre-charging circuit generally needs to be added to the output circuit of the high-voltage power battery. The pre-charging circuit includes a pre-charging resistor, a pre-charging relay and a corresponding control circuit. The principle is to pre-charge the capacitive load in the high-voltage load circuit before the high-voltage relay is pulled in. When the load voltage is pre-charged to close to the battery bus voltage, the high-voltage relay is pulled in, so that the high-voltage relay will not produce production when the high-voltage relay is pulled in. high current, thus protecting the high voltage relay contacts.

In the embodiment of the present invention, the bidirectional voltage conversion module can also be used to precharge the high-voltage circuit, that is, before the high voltage is applied to the vehicle, the low-voltage on-board power supply is boosted by the bidirectional voltage conversion module to precharge the high-voltage load capacitor. The high-voltage relay is then pulled in, so the pre-charging circuit of the original high-voltage system can be cancelled, and the hardware cost of the high-voltage circuit can be reduced. FIG. 6 is a flowchart of a high-voltage circuit precharging provided by an embodiment of the present invention. Please refer to FIG. 6 . The high-voltage circuit precharging includes the following steps:

S301: In response to a vehicle start signal, determine whether the ambient temperature of the vehicle is lower than a preset temperature;

S302: when the ambient temperature of the vehicle is not lower than the preset temperature, set the bidirectional voltage conversion module to a forward working state; the bidirectional voltage conversion module can convert the high voltage output from the high voltage power battery into low voltage power in the forward working state .

S303: After responding to the high voltage signal on the vehicle, set the bidirectional voltage conversion module to the reverse working state, and precharge the high voltage load capacitor;

S304: Determine whether the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

S305: When the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery, control the high-voltage power on the vehicle;

S306: Connect the high-voltage power battery to the starter motor after the high-voltage power on the vehicle is completed.

Further, after judging whether the ambient temperature of the vehicle is lower than the preset temperature, the method further includes:

When the ambient temperature of the vehicle is not lower than the preset temperature, the bidirectional voltage conversion module is set to the forward working state.

Optionally, it also includes setting the bidirectional voltage conversion module to a forward working state after the vehicle is started. In the forward working state, the bidirectional voltage conversion module converts the high-voltage power of the second voltage output by the high-voltage power battery into the low-voltage power of the first voltage, and supplies power to the low-voltage vehicle power supply and the low-voltage load.

An embodiment of the present invention further provides a computer-readable storage medium, where at least one instruction, at least one piece of program, code set or instruction set is stored in the storage medium, the at least one instruction, the at least one piece of program, the at least one piece of program, the The code set or the instruction set is loaded and executed by the processor to realize the above-mentioned low temperature cold start method of the hybrid electric vehicle.

Optionally, in this embodiment, the above-mentioned storage medium may be located in at least one network server among multiple network servers of a computer network. Optionally, in this embodiment, the above-mentioned storage medium may include but is not limited to: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic Various media that can store program codes, such as discs or optical discs.

An embodiment of the present invention further provides a device, the device includes a processor and a memory, the memory stores at least one instruction, at least one segment of program, code set or instruction set, the at least one instruction, the at least one segment of The program, the code set or the instruction set is loaded and executed by the processor to implement the above-mentioned method for low temperature cold start of a hybrid electric vehicle.

The memory can be used to store software programs and modules, and the processor executes various functional applications and data processing by running the software programs and modules stored in the memory. The memory may mainly include a stored program area and a stored data area, wherein the stored program area may store the operating system, application programs required for functions, etc.; the stored data area may store data created according to the use of the device, and the like. Additionally, the memory may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device. Accordingly, the memory may also include a memory controller to provide processor access to the memory.

The embodiment of the present invention adopts a bidirectional voltage conversion module, and in a low temperature environment, a 12V battery and a high-voltage lithium battery can be used as an energy system to drive the engine starter motor, which can make up for the shortcoming of the low-temperature discharge power of the high-voltage lithium battery pack to a certain extent. Besides, the present invention also has a pre-charging function, which can cancel the pre-charging circuit in the original high-voltage system and reduce the hardware cost of the high-voltage circuit.

In the above-mentioned embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in each of the embodiments, reference may be made to the relevant descriptions of other embodiments.

Those skilled in the art may also understand that various illustrative logical blocks (illustrative logical blocks), units, and steps listed in the embodiments of the present invention may be implemented by electronic hardware, computer software, or a combination of the two. To clearly demonstrate the interchangeability of hardware and software, the various illustrative components, units and steps described above have generally described their functions. Whether such functionality is implemented in hardware or software depends on the specific application and overall system design requirements. Those skilled in the art may use various methods to implement the described functions for each specific application, but such implementation should not be construed as exceeding the protection scope of the embodiments of the present invention.

The specific embodiments described above further describe the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A low-temperature cold start device for a hybrid vehicle, comprising:

the bidirectional voltage conversion module (101) is used for converting low voltage of first voltage output by a low-voltage vehicle-mounted power supply into high voltage of second voltage in a reverse working state or converting high voltage of the second voltage output by a high-voltage power battery into low voltage of the first voltage in a forward working state;

the temperature judging module (102) is used for responding to the starting signal to judge whether the ambient temperature of the vehicle is lower than a preset temperature;

the state setting module (103) is used for setting the bidirectional voltage conversion module (101) to be in a reverse working state when the ambient temperature of the vehicle is lower than a preset temperature;

the first power supply connection module (104) is used for connecting the bidirectional voltage conversion module (101) and the high-voltage power battery with a starting motor when the bidirectional voltage conversion module (101) is in a reverse working state;

the low-voltage vehicle-mounted power supply is connected with one end of the bidirectional voltage conversion module (101), the other end of the bidirectional voltage conversion module (101) is connected with the starting motor, and the high-voltage power battery is connected with the starting motor.

2. The low-temperature cold start device of a hybrid vehicle according to claim 1, wherein the state setting module (103) is further configured to set the bidirectional voltage conversion module (101) to a forward operation state when the ambient temperature of the vehicle is not lower than a preset temperature.

3. The hybrid vehicle cold start apparatus according to claim 1 or 2, characterized by further comprising:

the pre-charging module (105) is used for responding to a high-voltage signal on the whole vehicle, setting the bidirectional voltage conversion module (101) to be in a reverse working state and pre-charging a high-voltage load capacitor;

the voltage comparison module (106) is used for judging whether the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery or not;

the high-voltage power-on module (107) is used for controlling the high voltage on the whole vehicle when the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery;

and the second power supply connection module (108) is used for connecting the high-voltage power battery with the starting motor after the high voltage on the whole vehicle is completed.

4. A hybrid vehicle cold start method at a low temperature, characterized by employing the hybrid vehicle cold start apparatus according to any one of claims 1 to 3, comprising:

s201: responding to a vehicle starting signal, and judging whether the vehicle environment temperature is lower than a preset temperature or not;

s202: when the ambient temperature of the vehicle is lower than a preset temperature, setting the bidirectional voltage conversion module (101) to be in a reverse working state;

s203: when the bidirectional voltage conversion module (101) is in a reverse working state, the bidirectional voltage conversion module (101) and the high-voltage power battery are both communicated with the starting motor.

5. The low-temperature cold start method for the hybrid vehicle according to claim 4, wherein after determining whether the ambient temperature of the vehicle is lower than a preset temperature, the method further comprises:

s302: and when the ambient temperature of the vehicle is not lower than the preset temperature, setting the bidirectional voltage conversion module (101) to be in a positive working state.

6. The hybrid vehicle cold start method according to claim 4 or 5, characterized by further comprising:

s303: after responding to a high-voltage signal on the whole vehicle, setting the bidirectional voltage conversion module (101) to be in a reverse working state, and pre-charging a high-voltage load capacitor;

s304: judging whether the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery or not;

s305: when the charging voltage of the high-voltage load capacitor is close to the output voltage of the high-voltage power battery, controlling the high voltage of the whole vehicle;

s306: and after the high voltage on the whole vehicle is completed, the high voltage power battery is communicated with the starting motor.

7. The hybrid vehicle cold start method according to claim 4, characterized by further comprising:

and after the vehicle is started, setting the bidirectional voltage conversion module (101) to be in a forward working state.

8. The hybrid vehicle cold start method according to claim 4, characterized in that the bidirectional voltage conversion module (101) comprises a bidirectional DC/DC converter.

9. A computer readable storage medium having stored therein at least one instruction, at least one program, a set of codes, or a set of instructions that is loaded and executed by a processor to implement the hybrid vehicle cold start method of any one of claims 4-8.

10. An apparatus comprising a processor and a memory having stored therein at least one instruction, at least one program, set of codes, or set of instructions that is loaded and executed by the processor to implement a hybrid vehicle cold start method as claimed in any one of claims 4-8.

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