阅读说明：本技术 新能源汽车低温充电方法和装置 (Low-temperature charging method and device for new energy automobile ) 是由 胡志敏 陈玉封 刁红宾 高天 侯文涛 郭贵贤 于 2019-11-19 设计创作，主要内容包括：本发明涉及新能源汽车领域,提供一种新能源汽车低温充电方法、装置以及新能源汽车。所述新能源汽车包括用于对新能源汽车的电池包进行加热的负载,该方法包括：检测所述电池包的温度；当检测到所述电池包的温度小于预设值时,控制所述负载开启；控制电池包充电设备输出第一电流,直到检测到所述电池包的温度大于等于预设值时,控制所述电池包充电设备输出第二电流以对所述电池包进行正常充电,其中所述第一电流小于所述负载的消耗电流,并小于所述第二电流。本发明可以降低运算负荷,减少开发成本。(The invention relates to the field of new energy automobiles, and provides a low-temperature charging method and device for a new energy automobile and the new energy automobile. The new energy automobile comprises a load for heating a battery pack of the new energy automobile, and the method comprises the following steps: detecting the temperature of the battery pack; when the temperature of the battery pack is detected to be smaller than a preset value, controlling the load to be started; controlling a battery pack charging device to output a first current until the temperature of the battery pack is detected to be greater than or equal to a preset value, and controlling the battery pack charging device to output a second current to normally charge the battery pack, wherein the first current is smaller than the consumption current of the load and smaller than the second current. The invention can reduce the operation load and the development cost.)

1. A low-temperature charging method for a new energy automobile is characterized in that the new energy automobile comprises a load for heating a battery pack of the new energy automobile, and the method comprises the following steps:

detecting the temperature of the battery pack;

when the temperature of the battery pack is detected to be smaller than a preset value, controlling the load to be started;

controlling a battery pack charging device to output a first current until the temperature of the battery pack is detected to be greater than or equal to a preset value, and controlling the battery pack charging device to output a second current to normally charge the battery pack, wherein the first current is smaller than the consumption current of the load and smaller than the second current.

2. The low-temperature charging method for the new energy automobile according to claim 1, wherein before the temperature of the battery pack is detected, the method further comprises:

and controlling the new energy automobile to be powered on, and controlling the battery pack charging equipment not to output current.

3. The low-temperature charging method for the new energy automobile according to claim 1, wherein after the temperature of the battery pack is detected, the method further comprises:

and when the temperature of the battery pack is detected to be greater than or equal to a preset value, controlling the battery pack charging equipment to output the second current so as to normally charge the battery pack.

4. The low-temperature charging method for the new energy automobile according to claim 1, wherein the load comprises a heater and a high-low voltage converter.

5. The low-temperature charging method for the new energy automobile according to claim 1, wherein the second current is also used for being consumed by the load.

6. The utility model provides a new energy automobile low temperature charging device which characterized in that, new energy automobile includes the load that is used for heating new energy automobile's battery package, and the device includes:

a detection unit and a control unit, wherein,

the detection unit is used for detecting the temperature of the battery pack;

the control unit is used for controlling the load to be started when the temperature of the battery pack is detected to be smaller than a preset value;

the control unit is further used for controlling a battery pack charging device to output a first current until the temperature of the battery pack is detected to be greater than or equal to a preset value, and controlling the battery pack charging device to output a second current to normally charge the battery pack, wherein the first current is smaller than the consumption current of the load and smaller than the second current.

7. The low-temperature charging device for the new energy automobile according to claim 6, wherein before detecting the temperature of the battery pack, the control unit is further configured to:

and controlling the new energy automobile to be powered on, and controlling the battery pack charging equipment not to output current.

8. The low-temperature charging device for the new energy automobile according to claim 6, wherein after detecting the temperature of the battery pack, the control unit is further configured to:

and when the temperature of the battery pack is detected to be greater than or equal to a preset value, controlling the battery pack charging equipment to output the second current so as to normally charge the battery pack.

9. The low-temperature charging device for the new energy automobile according to claim 6, wherein the load comprises a heater and a high-low voltage converter.

10. A new energy automobile, which is characterized by comprising the new energy automobile low-temperature charging device of any one of claims 6 to 9.

Technical Field

The invention relates to the technical field of new energy automobiles, in particular to a low-temperature charging method and device for a new energy automobile.

Background

Current new energy vehicle, especially pure electric vehicle type have the battery package function of charging. However, at present, new energy automobiles mostly adopt lithium batteries as power batteries, and the lithium batteries cannot be charged at low temperature (for example, below-20 ℃), otherwise the service life of the batteries is affected, and even fire and explosion can be caused.

At present, the relay of the battery pack is disconnected during low-temperature charging, so that current is prevented from flowing into the battery, and the relay of the battery pack is closed and charging is started after the temperature reaches the chargeable temperature. However, the method needs to additionally consider the power-on and power-off flow of the relay and the interaction logic of the power-on and power-off flow, and the operation load of the whole vehicle controller is large.

Disclosure of Invention

In view of this, the present invention provides a low-temperature charging method for a new energy vehicle, so as to reduce the operation load and the development cost.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a low-temperature charging method for a new energy automobile, wherein the new energy automobile comprises a load for heating a battery pack of the new energy automobile, and the method comprises the following steps: detecting the temperature of the battery pack; when the temperature of the battery pack is detected to be smaller than a preset value, controlling the load to be started; controlling a battery pack charging device to output a first current until the temperature of the battery pack is detected to be greater than or equal to a preset value, and controlling the battery pack charging device to output a second current to normally charge the battery pack, wherein the first current is smaller than the consumption current of the load and smaller than the second current.

Further, before detecting the temperature of the battery pack, the method further includes: and controlling the new energy automobile to be powered on, and controlling the battery pack charging equipment not to output current.

Further, after detecting the temperature of the battery pack, the method further includes: and when the temperature of the battery pack is detected to be greater than or equal to a preset value, controlling the battery pack charging equipment to output the second current so as to normally charge the battery pack.

Further, the load includes a heater and a high-low voltage converter.

Further, the second current is also used for being consumed by the load.

Compared with the prior art, the low-temperature charging method for the new energy automobile has the following advantages:

by turning on the load for heating the battery pack at a low temperature (i.e., when the temperature of the battery pack is less than a preset value), and causing the battery pack charging apparatus to output a first current less than the current consumed by the load until the temperature of the battery pack is greater than or equal to the preset value, the battery pack can be subjected to micro-discharge at the low temperature, thereby avoiding charging the battery pack. The invention does not need to control the relay of the battery pack, thereby reducing the operation load and the development cost.

Another objective of the present invention is to provide a low-temperature charging device for a new energy vehicle, so as to reduce the operation load and the development cost.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a low-temperature charging device for a new energy automobile, wherein the new energy automobile comprises a load for heating a battery pack of the new energy automobile, and the device comprises: the battery pack temperature detection device comprises a detection unit and a control unit, wherein the detection unit is used for detecting the temperature of the battery pack; the control unit is used for controlling the load to be started when the temperature of the battery pack is detected to be smaller than a preset value; the control unit is further used for controlling a battery pack charging device to output a first current until the temperature of the battery pack is detected to be greater than or equal to a preset value, and controlling the battery pack charging device to output a second current to normally charge the battery pack, wherein the first current is smaller than the consumption current of the load and smaller than the second current.

Further, before detecting the temperature of the battery pack, the control unit is further configured to: and controlling the new energy automobile to be powered on, and controlling the battery pack charging equipment not to output current.

Further, after detecting the temperature of the battery pack, the control unit is further configured to: and when the temperature of the battery pack is detected to be greater than or equal to a preset value, controlling the battery pack charging equipment to output the second current so as to normally charge the battery pack.

Further, the load includes a heater and a high-low voltage converter.

Compared with the prior art, the new energy automobile low-temperature charging device and the new energy automobile low-temperature charging method have the same advantages, and are not described herein again.

Another objective of the present invention is to provide a new energy vehicle to reduce the calculation load and the development cost.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a new energy automobile comprises the new energy automobile low-temperature charging device.

Compared with the prior art, the new energy automobile and the low-temperature charging method for the new energy automobile have the same advantages, and are not described herein again.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention.

In the drawings:

fig. 1 is a flowchart of a low-temperature charging method for a new energy vehicle according to an embodiment of the present invention;

fig. 2 is a schematic current diagram of the new energy vehicle during low-temperature heating according to an embodiment of the present invention;

fig. 3 is a flowchart of a low-temperature charging method for a new energy vehicle according to another embodiment of the present invention;

fig. 4 is a block diagram of a low-temperature charging device for a new energy vehicle according to an embodiment of the present invention.

Description of reference numerals:

1 detection unit 2 control unit

Detailed Description

In addition, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.

The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Fig. 1 is a flowchart of a low-temperature charging method for a new energy vehicle according to an embodiment of the present invention. As shown in fig. 1, the new energy automobile includes a load for heating a battery pack of the new energy automobile, and the method includes:

step S11, detecting the temperature of the battery pack;

specifically, a new energy vehicle, especially an electric vehicle, mostly uses a lithium battery, and the temperature of the lithium battery is below a preset value (generally-20 ℃) and cannot be charged, so the embodiment of the present invention first needs to detect the temperature of the battery pack to determine which control method to use.

Step S12, when the temperature of the battery pack is detected to be less than a preset value, controlling the load to be started;

specifically, as shown above, the preset value may preferably be-20 ℃, and the load may include a heater that heats the battery pack and a high-low voltage converter (DC-DC) for high-low voltage conversion of the heater. Since the Battery pack cannot be charged when the temperature of the Battery pack is less than the preset value, when it is detected that the temperature of the Battery pack is less than the preset value, a Battery Management System (BMS) may first start a load to heat the Battery pack.

Step S13, controlling a battery pack charging device to output a first current, and controlling the battery pack charging device to output a second current to charge the battery pack normally until the temperature of the battery pack is detected to be greater than or equal to a preset value, where the first current is less than the current consumption of the load.

Specifically, the load needs to be powered during operation, and the embodiment of the present invention may use a charging device to supply power, for example, an On Board Charger (OBC). Because the temperature of the battery pack can still discharge even below the preset value, during the heating of the battery pack, the Hybrid Control Unit (HCU) only controls the charging device to output the first current smaller than the consumption current of the load, so that the battery pack can be subjected to micro-discharge for the load, and the current can be prevented from flowing into the battery pack. As shown in fig. 2, for example, the first current outputted by the charger is smaller than the consumption current of the load by 1A, and the middle part of the two lines is supplemented with the discharge of 1A by the battery pack to reach the current required to be consumed by the load.

When the temperature of the battery pack reaches a preset value and can be charged, the OBC is controlled to output a second current (the second current is the current which can be consumed by the load and can be charged by the battery pack) which is larger than the first current, so that the battery pack is normally charged. The load may not be turned off at this time and the battery pack may continue to be heated.

Fig. 3 is a flowchart of a low-temperature charging method for a new energy vehicle according to another embodiment of the present invention. As shown in fig. 3, the method includes:

step S31, controlling the new energy automobile to be powered on, and controlling the battery pack charging equipment not to output current;

specifically, the embodiment provides a more complete low-temperature charging process of the new energy vehicle. The method comprises the steps that firstly, the new energy automobile is normally electrified, and after the electrification is finished, the battery pack charging equipment is controlled not to output current temporarily, so that the current is prevented from flowing into the battery pack when the temperature of the battery pack is lower than a preset value.

Step S32, detecting the temperature of the battery pack;

step S33, judging whether the temperature of the battery pack is less than a preset value;

step S34, when the temperature of the battery pack is detected to be less than a preset value, controlling the load to be started;

step S35, controlling a battery pack charging device to output a first current, and controlling the battery pack charging device to output a second current to charge the battery pack normally until the temperature of the battery pack is detected to be greater than or equal to a preset value, where the first current is less than the current consumption of the load.

Specifically, in steps S32-S35, after the battery pack charging device is controlled to output the first current, the temperature of the battery pack is detected again (at this time, the load heats the battery pack, and the temperature of the battery pack gradually increases), if the temperature of the battery pack is still less than the preset value, the first current is kept being output, and then the temperature of the battery pack is continuously detected until the temperature of the battery pack is greater than or equal to the preset value, and the battery pack charging device is controlled to output the second current. In addition, other portions of the embodiment in steps S32-S35 are similar to the above, and are not repeated herein.

And step S36, when the temperature of the battery pack is detected to be greater than or equal to a preset value, controlling the battery pack charging equipment to output the second current so as to normally charge the battery pack.

Specifically, if after step S33, when the temperature of the battery pack is directly determined to be greater than or equal to the preset value, it is determined that the battery pack can be directly charged, and the battery pack charging device can be directly controlled to output the second current to directly perform normal charging without waiting for the load to be turned on.

Fig. 4 is a block diagram of a low-temperature charging device for a new energy vehicle according to an embodiment of the present invention. As shown in fig. 4, the new energy vehicle includes a load for heating a battery pack of the new energy vehicle, and the apparatus includes: a detection unit 1 and a control unit 2, wherein the detection unit 1 is used for detecting the temperature of the battery pack; the control unit 2 is used for controlling the load to be started when the temperature of the battery pack is detected to be smaller than a preset value; the control unit 2 is further configured to control a battery pack charging device to output a first current, and control the battery pack charging device to output a second current to normally charge the battery pack until the temperature of the battery pack is detected to be greater than or equal to a preset value, where the first current is smaller than a consumption current of the load and smaller than the second current.

Further, before detecting the temperature of the battery pack, the control unit 2 is further configured to: and controlling the new energy automobile to be powered on, and controlling the battery pack charging equipment not to output current.

Further, after detecting the temperature of the battery pack, the control unit 2 is further configured to: and when the temperature of the battery pack is detected to be greater than or equal to a preset value, controlling the battery pack charging equipment to output the second current so as to normally charge the battery pack.

Further, the load includes a heater and a high-low voltage converter.

The above-described low-temperature charging device for a new energy vehicle is similar to the above-described embodiment of the low-temperature charging method for a new energy vehicle, and is not described herein again.

The embodiment of the invention also provides a new energy automobile which comprises the low-temperature charging device for the new energy automobile.

By turning on the load for heating the battery pack at a low temperature (i.e., when the temperature of the battery pack is less than a preset value), and causing the battery pack charging apparatus to output a first current less than the current consumed by the load until the temperature of the battery pack is greater than or equal to the preset value, the battery pack can be subjected to micro-discharge at the low temperature, thereby avoiding charging the battery pack. The invention does not need to control the relay of the battery pack, thereby reducing the operation load and the development cost.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.