A new energy vehicle battery intelligent charging method

Abstract

The present invention provides a new energy vehicle battery intelligent charging method. Considering the characteristics of the power battery, the number of times the power battery can be recharged and the interval between each recharge are accurately calculated according to the power of the power battery when the vehicle is powered off and the power consumption of the vehicle. According to the number and interval, a charging plan is planned, and the vehicle is awakened and recharged according to the charging plan. After recharging, when the power battery is about to be fed for the last recharge, the power battery power is monitored in real time, and the recharge is stopped when the power battery power reaches the lower limit threshold, and the user is reminded that the power battery power is insufficient and please charge as soon as possible. The number of wake-ups is reduced as much as possible, unnecessary power consumption and waste are reduced, and resources are saved; at the same time, the problem of the vehicle being stranded due to the power battery feeding caused by recharging the battery is avoided, and the risk of electric shock to maintenance personnel is prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of charging and discharging of new energy vehicles, and in particular to an intelligent charging method for a battery of a new energy vehicle. Background Art

[0002] At present, the development of electric vehicles is an important way to improve the competitiveness of the automobile industry, ensure energy security and develop a low-carbon economy.

[0003] The battery system of electric vehicles includes a high-voltage battery pack that provides a power source and a low-voltage battery that is used to power the entire vehicle's electrical appliances. As a core component in the automotive electrical system, the battery plays a very important role. For new energy vehicles, it serves as a power supply to meet the vehicle's power needs when the vehicle is not on high voltage. After the vehicle is powered off, due to the static current consumption of the vehicle and the self-discharge of the battery, if the vehicle is stored for a long time without use, it will cause the vehicle battery to be fed, resulting in problems such as the vehicle being unable to start and drive again. New energy vehicles can use the power battery to recharge the low-voltage battery to recharge when the battery is low, and try to avoid problems such as long-term storage and recharging of the battery.

[0004] In the prior art, the vehicle is usually awakened at a fixed time and the battery is recharged through the high-voltage power battery. After awakening, if the battery has sufficient power, no recharging is required. If the battery has insufficient power, the battery is recharged through the power battery.

[0005] However, with the above technical solution, regardless of whether the battery power is sufficient, the vehicle is woken up at a scheduled time, which increases the power consumption of the low-voltage electrical appliances of the entire vehicle. The higher the frequency of wake-up, the more electricity is wasted. In addition, the high-voltage power battery may be fed due to the regular battery replenishment and the power consumed after wake-up. If the high-voltage power battery is fed, when the vehicle is started again, even if the low-voltage system is powered on, the high voltage cannot be turned on due to the power feeding of the high-voltage system, and the vehicle cannot be driven, resulting in a breakdown. Summary of the invention

[0006] The present invention proposes a new energy vehicle battery intelligent charging method and system, which determines the number of times the battery can be charged and the vehicle wake-up time after the vehicle is under high voltage, and completes the charging operation of the low-voltage battery.

[0007] In order to solve the above technical problems, the present invention provides a new energy vehicle battery intelligent charging method, comprising the following steps:

[0008] Step S1: when the target vehicle is powered off for the first time, power battery information, vehicle information and low-voltage battery information are obtained;

[0009] Step S2: Based on the power battery information, vehicle information, and low-voltage battery information, determine whether the power battery can supplement the low-voltage battery. If supplementation is possible, proceed to the subsequent steps; otherwise, remind the user to charge the power battery.

[0010] Step S3: Determine the power consumption of the low-voltage electrical appliances, and calculate the next power replenishment wake-up time based on the power consumption of the low-voltage electrical appliances. When the wake-up time is reached, wake up the vehicle to replenish the low-voltage battery.

[0011] Preferably, the method for determining whether the power battery can supplement the low-voltage battery in step S2 is specifically as follows: the available discharge amount of the power battery is obtained by subtracting the self-discharge amount P0 of the power battery from the starting discharge threshold SOC1 and the ending discharge threshold SOC2 of the power battery; when the available discharge amount of the power battery is greater than the supplement amount of the low-voltage battery, it is determined that the low-voltage battery can be supplemented.

[0012] Preferably, step S2 also includes calculating the number of times N that the power battery can recharge the low-voltage battery. When N is not less than 1, it indicates that the power battery can be recharged. After completing step S3 to recharge the low-voltage battery, the number of recharges N is reduced by one. Then, steps S2 to S3 are repeated to complete the recharging of the low-voltage battery.

[0013] Preferably, the formula for calculating the number of times N that the power battery can supplement the low-voltage battery is specifically:

[0014]

[0015] In the formula, E0 represents the energy of the power battery, P0 represents the self-discharge of the power battery, E1 represents the pre-charge power consumption when the high-voltage system is connected, E2 represents the power consumption of the low-voltage accessories, E3 represents the power charged by the power battery to the low-voltage battery, and η represents the efficiency of the high-voltage to low-voltage conversion system.

[0016] Preferably, the power consumption E2 of the low-voltage accessory is calculated by the following formula:

[0017]

[0018] Among them, U represents the low-voltage battery voltage, I1 represents the low-voltage accessory current, and T1 represents the single charging time of the power battery to the low-voltage battery;

[0019] The amount of electricity charged by the power battery to the low-voltage battery is calculated by the following formula:

[0020]

[0021] Among them, I2 represents the charging current of the power battery to the low-voltage battery.

[0022] Preferably, the power consumption of the low-voltage electrical appliances in step S3 includes:

[0023] 1) When the vehicle is powered on for the first time, the power consumption of the low-voltage system from the working state to the dormant state is C1;

[0024] 2) Static power consumption C2 when the vehicle is in dormant state;

[0025] 3) When the vehicle is stationary, the self-discharge amount of the low-voltage battery is C3.

[0026] Preferably, when the target vehicle is powered off for the first time, the method for calculating the next power replenishment wake-up time in step S4 is specifically as follows: first, the power replenishment amount required by the low-voltage battery is calculated through the capacity of the low-voltage battery, the power replenishment start threshold P2, the power replenishment end threshold P1 and the low-voltage system power consumption C1; then, the power consumption of the low-voltage battery is calculated through the static power consumption C2 and the self-discharge amount C3 of the low-voltage battery; finally, the next power replenishment wake-up time is calculated by dividing the power replenishment amount required by the low-voltage battery by the power consumption of the low-voltage battery.

[0027] Preferably, when the target vehicle is powered off for the first time, the formula for calculating the next power-up wake-up time is:

[0028]

[0029] Preferably, when the target vehicle is powered off for the first time, the method for calculating the next power replenishment wake-up time in step S3 is specifically as follows: first, the power replenishment amount required by the low-voltage battery is calculated through the capacity of the low-voltage battery, the power replenishment start threshold P2 and the power replenishment end threshold P1, and then the power consumption of the low-voltage battery is calculated through the static power consumption C2 and the self-discharge amount C3 of the low-voltage battery. Finally, the next power replenishment wake-up time is calculated by dividing the power replenishment amount required by the low-voltage battery by the power consumption of the low-voltage battery.

[0030] Preferably, when the target vehicle is not powered off for the first time, the formula for calculating the next power-on wake-up time is:

[0031]

[0032] The beneficial effects of the present invention are that, taking into account the characteristics of the power battery, the number of times the power battery can be recharged and the next recharge wake-up time are accurately calculated according to the power level of the power battery when the vehicle is powered off and the power consumption of the vehicle, a recharge plan is planned according to the number of times and the interval time, and the vehicle is woken up and recharged according to the recharge plan; the number of wake-ups is reduced as much as possible, unnecessary power consumption and waste are reduced, and resources are saved; at the same time, the problem of breakdown caused by power battery feeding due to recharging the battery and the risk of electric shock to maintenance personnel are avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0034] The embodiments of the present invention are described below based on the drawings. The present invention is not limited to the embodiments described below, and various modifications are possible as long as they have substantially the same structure and can achieve substantially the same effects as the present invention.

[0035] like Figure 1 As shown, the present invention provides a new energy vehicle battery intelligent charging method, comprising the following steps:

[0036] Step S1: when the target vehicle is powered off for the first time, power battery information, vehicle information and low-voltage battery information are obtained;

[0037] In the embodiment of the present invention, the vehicle information includes: the high-voltage to low-voltage conversion system efficiency η, the low-voltage accessory consumption current I1, the pre-charge consumption power E1 when the high-voltage system is connected, the low-voltage accessory consumption power E2, and the low-voltage accessory consumption current I1;

[0038] The battery information includes: low-voltage battery voltage U, low-voltage battery capacity C0;

[0039] The information of the power battery includes: the energy E0 of the power battery, the self-discharge of the power battery P0, the amount of power E3 charged by the power battery to the low-voltage battery, the charging current I2 of the power battery to the low-voltage battery, and the single charging time T1 of the power battery to the low-voltage battery.

[0040] Among them, low-voltage accessories consume power The amount of power battery charging the low-voltage battery

[0041] Step S2: Based on the power battery information, vehicle information, and low-voltage battery information, determine whether the power battery can supplement the low-voltage battery. If supplementation is possible, proceed to the subsequent steps; otherwise, remind the user to charge the power battery.

[0042] Specifically, the embodiment of the present invention uses the remaining power of the power battery after the vehicle is powered off or awakened from sleep as the starting discharge threshold SOC1 of the power battery, and the minimum remaining power of the power battery SOC2 as the discharge termination threshold of the power battery; in this way, the available discharge capacity SOC1-SOC2 of the power battery can be obtained.

[0043] The power supply capacity of the power battery is obtained by subtracting the self-discharge amount P0 of the power battery from the starting discharge threshold SOC1 and the ending discharge threshold SOC2 of the power battery. When the power supply capacity of the power battery is greater than the rechargeable capacity of the low-voltage battery, it is determined that the low-voltage battery can be recharged.

[0044] It can be expressed by the formula: when E0×(SOC1-SOC2-P0)≥E1+(E2+E3) / η, it means that the power can be used to supplement the low-voltage battery.

[0045] Step S3: Determine the power consumption of the low-voltage electrical appliances, and calculate the next power replenishment wake-up time based on the power consumption of the low-voltage electrical appliances. When the wake-up time is reached, wake up the vehicle to replenish the low-voltage battery.

[0046] In the embodiment of the present invention, according to the battery characteristics, it can be known that the battery power threshold P2 corresponding to the minimum voltage of 9 volts for maintaining the normal operation of the low-voltage system without damaging the battery, and P2 is used as the starting threshold for battery recharge, indicating that when the battery power is lower than P2, the battery needs to be recharged, and the power that needs to be reached after the battery is recharged is used as the termination threshold for recharge.

[0047] The power consumption of low-voltage electrical appliances is divided into three parts:

[0048] 1) When the low voltage is powered on, the power consumed by the low voltage accessories is:

[0049] The vehicle is stationary and the low voltage power is turned on for the first time. During the process of the power supply switching from working state to sleep state, the power consumption of the low voltage system is C1 (Ah).

[0050] 2) The vehicle is in dormant state, and the static power consumption of the vehicle is:

[0051] The vehicle is in dormant state, and the static power consumption of the whole vehicle is C2 (Ah).

[0052] 3) When the vehicle is stationary, the self-discharge of the low-voltage battery:

[0053] When the vehicle is stationary, the self-discharge capacity of the low-voltage battery is C3 (Ah).

[0054] The next power replenishment wake-up time is calculated based on the power consumption of the low-voltage electrical appliances determined above:

[0055] 1) When the target vehicle is powered off for the first time, the next power-on wake-up time T1 is calculated using the following formula:

[0056]

[0057] 2) If the target vehicle is not powered off for the first time, the next power-on wake-up time T2 is calculated using the following formula:

[0058]

[0059] At the same time, the embodiment of the present invention can calculate the next charging time of the low-voltage battery multiple times by calculating the number of times N that the power battery can charge the low-voltage battery, thereby completing the charging work of the low-voltage battery.

[0060] Specifically, when N is not less than 1, it indicates that the power battery can be recharged, otherwise the user is reminded to charge the power battery.

[0061] The formula for calculating the number of times N that the power battery can replenish the low-voltage battery is as follows:

[0062]

[0063] In the formula, E0 represents the energy of the power battery, P0 represents the self-discharge of the power battery, E1 represents the pre-charge power consumption when the high-voltage system is connected, E2 represents the power consumption of the low-voltage accessories, E3 represents the power charged by the power battery to the low-voltage battery, and η represents the efficiency of the high-voltage to low-voltage conversion system.

[0064] In a specific implementation process, after executing step 3, the number of charging times N is reduced by one, and then steps S2 to S3 are repeated to complete the charging work of the low-voltage battery.

[0065] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for intelligently charging batteries for new energy vehicles, characterized in that: The following steps are involved: Step S1: when the target vehicle is powered off for the first time, power battery information, vehicle information and low-voltage battery information are obtained; Step S2: Based on the power battery information, vehicle information, and low-voltage battery information, determine whether the power battery can supplement the low-voltage battery. If supplementation is possible, proceed to the subsequent steps; otherwise, remind the user to charge the power battery. Step S3: determining the power consumption of the low-voltage electrical appliances, and calculating the next power replenishment wake-up time based on the power consumption of the low-voltage electrical appliances, and waking up the vehicle to replenish the low-voltage battery when the wake-up time is reached; The method for judging whether the power battery can supplement the low-voltage battery in step S2 is as follows: the available discharge amount of the power battery is obtained by subtracting the self-discharge amount P0 of the power battery from the starting discharge threshold SOC1 and the ending discharge threshold SOC2 of the power battery; when the available discharge amount of the power battery is greater than the supplement amount of the low-voltage battery, it is judged that the low-voltage battery can be supplemented; Step S2 also includes calculating the number of times N that the power battery can supplement the low-voltage battery. When N is not less than 1, it means that the power battery can be supplemented. After completing step S3 to supplement the low-voltage battery, the number of times N is reduced by one. Then, steps S2 to S3 are repeated to complete the supplement of the low-voltage battery. The formula for calculating the number of times N that the power battery can supplement the low-voltage battery is specifically: In the formula, E0 represents the energy of the power battery, P0 represents the self-discharge of the power battery, E1 represents the pre-charge power consumption when the high-voltage system is connected, E2 represents the power consumption of the low-voltage accessories, E3 represents the power charged by the power battery to the low-voltage battery, and η represents the efficiency of the high-voltage to low-voltage conversion system; The power consumption of the low-voltage electrical appliances in step S3 includes: 1) When the vehicle is powered on for the first time, the power consumption of the low-voltage system from the working state to the dormant state is C1; 2) Static power consumption C2 when the vehicle is in dormant state; 3) When the vehicle is stationary, the self-discharge of the low-voltage battery is C3; When the target vehicle is powered off for the first time, the method for calculating the next power replenishment wake-up time in step S3 is specifically as follows: first, the power replenishment amount required by the low-voltage battery is calculated by the capacity of the low-voltage battery, the power replenishment start threshold P2, the power replenishment end threshold P1 and the power consumption C1 of the low-voltage system, and then the power consumption of the low-voltage battery is calculated by the static power consumption C2 and the self-discharge amount C3 of the low-voltage battery, and finally the next power replenishment wake-up time is calculated by dividing the power replenishment amount required by the low-voltage battery by the power consumption of the low-voltage battery; When the target vehicle is powered off for the first time, the formula for calculating the next power-up wake-up time is: When the target vehicle is powered off for the first time, the method for calculating the next power replenishment wake-up time in step S3 is specifically as follows: first, the power replenishment amount required by the low-voltage battery is calculated by the capacity of the low-voltage battery, the power replenishment start threshold P2, and the power replenishment end threshold P1; then, the power consumption of the low-voltage battery is calculated by the static power consumption C2 and the self-discharge amount C3 of the low-voltage battery; finally, the next power replenishment wake-up time is calculated by dividing the power replenishment amount required by the low-voltage battery by the power consumption of the low-voltage battery; When the target vehicle is not powered off for the first time, the formula for calculating the next power-on wake-up time is: In the formula, C0 represents the capacity of the low-voltage battery.

2. The intelligent charging method for a new energy vehicle battery according to claim 1 is characterized in that: The power consumption E2 of the low-voltage accessory is calculated by the following formula: Among them, U represents the low-voltage battery voltage, I1 represents the low-voltage accessory current, and T1 represents the single charging time of the power battery to the low-voltage battery; The amount of electricity charged by the power battery to the low-voltage battery is calculated by the following formula: Among them, I2 represents the charging current of the power battery to the low-voltage battery.

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