CN104795857A - Lithium ion battery energy balance system and implementation method thereof - Google Patents

Lithium ion battery energy balance system and implementation method thereof Download PDF

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CN104795857A
CN104795857A CN201510128269.2A CN201510128269A CN104795857A CN 104795857 A CN104795857 A CN 104795857A CN 201510128269 A CN201510128269 A CN 201510128269A CN 104795857 A CN104795857 A CN 104795857A
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ion battery
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lithium ion
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付宇卓
李维嘉
刘婷
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SHANGHAI ZIZHU XINXING INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
Shanghai Jiao Tong University
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Shanghai Jiao Tong University
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Abstract

本发明公开了一种锂离子电池能量均衡系统及其实现方法,该系统包括:锂离子电池组、n个电压检测电路、n个DCDC转换器、n个主控芯片、数据处理芯片、CAN通讯模块及电流检测电路,锂离子电池组由n块锂离子电池单体串联组成,第k个电压检测电路的输入端连接第k个锂离子电池单体的正极和负极,并于需要进行电压检测时开始采样,采样值经隔离后被传送至第k组主控芯片,各DCDC转换器通过控制MOS管的开关,分别对锂离子电池组内各锂离子电池单体直接进行充电和放电,同时通过开关频率调节平衡电流,本发明利用二阶RC模型模拟锂离子电池化学模型,并利用线性回归所产生的SOC作为锂离子电池均衡的判断依据,达到均衡的目的。

The invention discloses a lithium-ion battery energy balance system and its realization method. The system comprises: a lithium-ion battery pack, n voltage detection circuits, n DCDC converters, n main control chips, data processing chips, CAN communication Module and current detection circuit, the lithium-ion battery pack is composed of n lithium-ion battery cells in series, the input terminal of the kth voltage detection circuit is connected to the positive and negative electrodes of the k-th lithium-ion battery cell, and voltage detection is performed when necessary Sampling starts at the beginning of time, and the sampled value is transmitted to the kth group of main control chips after isolation. Each DCDC converter controls the switch of the MOS tube to directly charge and discharge each lithium-ion battery cell in the lithium-ion battery pack, and at the same time By adjusting the balance current through the switching frequency, the invention uses the second-order RC model to simulate the lithium-ion battery chemical model, and uses the SOC generated by linear regression as the judgment basis for the balance of the lithium-ion battery to achieve the purpose of balance.

Description

锂离子电池能量均衡系统及其实现方法Lithium-ion battery energy balance system and its realization method

技术领域 technical field

本发明涉及一种锂离子电池能量均衡系统及其实现方法,特别是涉及一种基于电池SoC的锂离子电池能量均衡系统及其实现方法。 The invention relates to a lithium-ion battery energy balance system and its implementation method, in particular to a battery SoC-based lithium-ion battery energy balance system and its implementation method.

背景技术 Background technique

纯电动汽车发展的关键是电池。近年来,锂电池技术有了巨大的进步,磷酸铁锂、锰酸锂、钴酸锂等电池出现明显提高了锂电池的性能;但锂电池组内单体电池间的不一致性天然普遍存在。锂电池的各项参数在大规模生产过程中不可避免的产生一些微小的差异,主要表现为锂电池内阻、容量、开路电压等不一致。随着锂电池使用次数增多,长时间自放电和汽车中较大温差的影响,这些差异将会越来越大,从而锂电池组的电池间性能差异越来越大。而过充和过放都会对电池造成不可恢复的损害,同时又由于串联电池组的容量由组内最低的单体电池容量决定,所以一旦电池组中的某个电池出现深度放电或者过度充电,整个电池组必须停止原先的充放电状态,否则电池寿命会严重衰减,甚至会引发较大安全隐患。最极端的情况就是,锂电池组部分单体电池已经充满,部分单体电池已经放完,这时候,整个电池组既无法充电也无法放电。 The key to the development of pure electric vehicles is the battery. In recent years, lithium battery technology has made great progress. Lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide and other batteries have significantly improved the performance of lithium batteries; but the inconsistency between single cells in lithium battery packs is naturally widespread. The parameters of lithium batteries inevitably produce some slight differences in the mass production process, mainly manifested in inconsistencies in the internal resistance, capacity, and open circuit voltage of lithium batteries. With the increasing use of lithium batteries, long-term self-discharge and the influence of large temperature differences in automobiles, these differences will become larger and larger, so that the performance differences between lithium battery packs will become larger and larger. Both overcharging and overdischarging will cause irreversible damage to the battery. At the same time, since the capacity of the series battery pack is determined by the capacity of the lowest single battery in the pack, once a battery in the battery pack is deeply discharged or overcharged, The entire battery pack must stop the original charging and discharging state, otherwise the battery life will be severely reduced, and even cause a major safety hazard. The most extreme situation is that some of the single cells of the lithium battery pack have been fully charged, and some of the single cells have been discharged. At this time, the entire battery pack can neither be charged nor discharged.

锂离子电池均衡管理系统的均衡功能主要解决锂电池组内的不一致性,缩小电池间的差异,对于延长电池寿命、降低成本具有重大意义,同时也能增加放电量。目前均衡方法主要是主动均衡和被动均衡,均衡判断准则分为电压均衡和SOC均衡。根本上说,电池均衡是电池组内各个单体电池间存储的电量均衡,电压值只是电池的一个外在特性,不能反映出电池SOC,因此根据电压作为判别的均衡方法不能非常有效。因此,如何得到锂离子电池的SOC成为了均 衡系统一个关键的部分,同时也是世界一个重要的难题。如何控制均衡电路也是一个较为复杂的问题,由于锂离子电池的高度非线性的特性,所以没有一个较为准确的数学模型。所以控制策略也较难确定,如输入输出的因素,如何有效控制等。 The balance function of the lithium-ion battery balance management system mainly solves the inconsistency in the lithium battery pack and reduces the difference between batteries, which is of great significance for extending battery life and reducing costs, and can also increase the discharge capacity. At present, the equalization methods are mainly active equalization and passive equalization, and the equalization judgment criteria are divided into voltage equalization and SOC equalization. Fundamentally speaking, battery equalization is the balance of power stored among the individual cells in the battery pack. The voltage value is only an external characteristic of the battery and cannot reflect the battery SOC. Therefore, the equalization method based on voltage as a discrimination cannot be very effective. Therefore, how to obtain the SOC of lithium-ion batteries has become a key part of the balance system, and it is also an important problem in the world. How to control the equalization circuit is also a relatively complicated problem. Due to the highly nonlinear characteristics of lithium-ion batteries, there is no more accurate mathematical model. Therefore, it is difficult to determine the control strategy, such as the factors of input and output, how to effectively control them, etc.

发明内容 Contents of the invention

为克服上述现有技术存在的不足,本发明之目的在于提供一种锂离子电池能量均衡系统及其实现方法,在能量均衡转移的过程中通过锂离子电池的SOC的估算,以此SOC为依据通过控制DCDC实现均衡,使得系统避免了电压均衡的方式所造成的误均衡,可靠性更高。 In order to overcome the deficiencies in the above-mentioned prior art, the object of the present invention is to provide a lithium-ion battery energy balance system and its implementation method, through the estimation of the SOC of the lithium-ion battery in the process of energy balance transfer, based on this SOC By controlling DCDC to achieve equalization, the system avoids false equalization caused by voltage equalization, and has higher reliability.

为达上述及其它目的,本发明提出一种锂离子电池能量均衡系统,包括: In order to achieve the above and other purposes, the present invention proposes a lithium-ion battery energy balance system, including:

锂离子电池组,所述锂离子电池组由n块锂离子电池单体串联组成,每个锂离子电池单体连接一电压检测电路及一DCDC转换器; Lithium-ion battery pack, the lithium-ion battery pack is composed of n lithium-ion battery cells connected in series, and each lithium-ion battery cell is connected to a voltage detection circuit and a DCDC converter;

n个电压检测电路,第k个电压检测电路的输入端分别连接第k个锂离子电池单体的正极和负极,并于需要进行电压检测时开始采样,其采样值经隔离后被传送至第k组主控芯片; n voltage detection circuits, the input terminals of the kth voltage detection circuit are respectively connected to the positive pole and negative pole of the kth lithium-ion battery cell, and sampling is started when voltage detection is required, and the sampled value is transmitted to the kth after isolation K group of main control chips;

n个DCDC转换器,各DCDC转换器通过控制MOS管的开关,分别对锂离子电池组内各锂离子电池单体直接进行充电和放电,同时通过开关频率调节平衡电流; n DCDC converters, each DCDC converter directly charges and discharges each lithium-ion battery cell in the lithium-ion battery pack by controlling the switch of the MOS tube, and at the same time adjusts the balance current through the switching frequency;

n个主控芯片,各主控芯片读出各锂离子电池单体对应的电压检测电路中锂离子电池的电压信息,然后将数据通过CAN总线传递到数据处理芯片60中; n main control chips, each main control chip reads the voltage information of the lithium ion battery in the voltage detection circuit corresponding to each lithium ion battery cell, and then transmits the data to the data processing chip 60 through the CAN bus;

数据处理芯片,通过线性回归的方法计算各个锂离子电池单体的SOC,同时根据模糊控制算法决定是否对锂离子电池组进行均衡,数据处理芯片60将均衡信号经过CAN通讯模块发送给各主控芯片,各主控芯片将均衡使能控制信号发送给各锂离子电池单体进行均衡控制; The data processing chip calculates the SOC of each lithium-ion battery cell through linear regression, and at the same time decides whether to balance the lithium-ion battery pack according to the fuzzy control algorithm. The data processing chip 60 sends the balanced signal to each main control unit through the CAN communication module Chip, each main control chip sends the balance enable control signal to each lithium-ion battery cell for balance control;

CAN通讯模块,负责实现所述主控芯片与所述数据处理芯片的通信; A CAN communication module is responsible for realizing the communication between the main control chip and the data processing chip;

电流检测电路,连接所述锂离子电池组与数据处理芯片,用于检测电池组的均衡电流以开启或关断初级和次级的开关管。 The current detection circuit is connected to the lithium-ion battery pack and the data processing chip, and is used to detect the balanced current of the battery pack to turn on or off the primary and secondary switch tubes.

进一步地,所述DCDC转换器采用双向同步反激式DCDC转换器,每个DCDC转换器均独立其他的DCDC,每个DCDC转换器的一端连接锂离子电池单体,另一端连接锂离子电池组。 Further, the DCDC converter adopts a bidirectional synchronous flyback DCDC converter, each DCDC converter is independent of other DCDCs, one end of each DCDC converter is connected to a lithium-ion battery cell, and the other end is connected to a lithium-ion battery pack .

进一步地,第k个双向同步反激式DCD转换器包括高频变压器(Tk)、初级开关管(Qkp)、次级开关管(Qks),初级开关管(Qkp)的源极连接至锂离子电池单体(Cellk)的负极,初级开关管(Qkp)的漏极连接至高频变压器(Tk)的初级的一端,高频变压器(Tk)的初级的另一端连接至锂离子电池单体(Cellk)的正极,次级开关管(Qks)的源极连接至该锂离子电池组的负极,次级开关管(Qks)的漏极连接至高频变压器(Tk)的次级的一端,高频变压器(Tk)的次级的另一端连接至锂离子电池组的正极。 Further, the kth bidirectional synchronous flyback DCD converter includes a high-frequency transformer (Tk), a primary switch (Qkp), a secondary switch (Qks), and the source of the primary switch (Qkp) is connected to the lithium-ion The negative pole of the battery cell (Cellk), the drain of the primary switch tube (Qkp) is connected to one end of the primary of the high-frequency transformer (Tk), and the other end of the primary of the high-frequency transformer (Tk) is connected to the lithium-ion battery cell ( Cellk), the source of the secondary switching tube (Qks) is connected to the negative pole of the lithium-ion battery pack, and the drain of the secondary switching tube (Qks) is connected to the secondary end of the high-frequency transformer (Tk), high The other end of the secondary of the frequency transformer (Tk) is connected to the positive terminal of the Li-ion battery pack.

为达到上述目的,本发明还提供一种锂离子电池能量均衡的实现方法,包括如下步骤: In order to achieve the above object, the present invention also provides a method for realizing energy balance of lithium-ion batteries, comprising the following steps:

步骤一,多次采集锂离子电池组中每块电池电压和电流的信息; Step 1, collecting information on the voltage and current of each battery in the lithium-ion battery pack multiple times;

步骤二,将每块电池的电压和电流的信息以及电池容量、寿命、开路电压和SOC的非线性曲线关系信息输入到数据处理芯片中; Step 2, input the voltage and current information of each battery and the nonlinear curve relationship information of battery capacity, service life, open circuit voltage and SOC into the data processing chip;

步骤三,将多次所测得的电池电压信号按照电池的二阶RC模型进行离散化,并通过线性回归的方法来对数据进行处理,得出有用矩阵信息,并通过矩阵算出锂离子电池所对应的开路电压; Step 3: discretize the battery voltage signal measured multiple times according to the second-order RC model of the battery, and process the data through linear regression to obtain useful matrix information, and calculate the lithium-ion battery voltage through the matrix. Corresponding open circuit voltage;

步骤四,根据所计算出的电池的开路电压,通过锂离子电池的开路电压和SOC关系曲线插值出锂离子电池的SOC,并计算电池组的平均SOC; Step 4, according to the calculated open circuit voltage of the battery, interpolate the SOC of the lithium ion battery through the open circuit voltage of the lithium ion battery and the SOC relationship curve, and calculate the average SOC of the battery pack;

步骤五,根据模糊控制的方法,将所计算出的锂离子电池的SOC判断电池所需要的均衡电流和均衡时间; Step 5, according to the method of fuzzy control, the calculated SOC of the lithium-ion battery is used to determine the equalization current and equalization time required by the battery;

步骤六,控制双向反激式DCDC转换器,通过检测DCDC上的电流达到一定的峰值,控制双向反激式DCDC的开关MOS管实现锂离子电池组中的电流 的通断,从而实现锂离子电池能量转移。 Step 6, control the bidirectional flyback DCDC converter, by detecting that the current on the DCDC reaches a certain peak value, control the switching MOS tube of the bidirectional flyback DCDC to realize the on-off of the current in the lithium-ion battery pack, thereby realizing the lithium-ion battery energy transfer.

进一步地,在步骤四之后,还包括如下步骤: Further, after step four, the following steps are also included:

计算锂离子电池组的电池分散度; Calculating cell dispersion for Li-ion battery packs;

判断电池分散度是否大于预定阈值; judging whether the degree of dispersion of the battery is greater than a predetermined threshold;

如果电池分散度小于该预定阈值时,则进入步骤一继续从检测锂离子电池电压开始;若锂离子电池分散度大于该预定阈值时,则进入步骤五。 If the degree of dispersion of the battery is less than the predetermined threshold, then enter step one and continue to start from detecting the voltage of the lithium-ion battery; if the degree of dispersion of the lithium-ion battery is greater than the predetermined threshold, then enter step five.

进一步地,于步骤一中,对锂离子电池的电池电压和电流信息提取频率较高,电压和电流信息间隔时间较短。 Further, in step 1, the battery voltage and current information of the lithium-ion battery is extracted more frequently, and the interval time of the voltage and current information is shorter.

进一步地,步骤三包括如下步骤:。 Further, step three includes the following steps: .

根据多次所测得的电压电流信息通过对锂离子电池的二阶RC模型离散化得到对SOC的估算; According to the voltage and current information measured multiple times, the SOC is estimated by discretizing the second-order RC model of the lithium-ion battery;

将锂离子电池模型化,将通过模型的电流作为激励I,锂离子电池的端电压和开路电压之差作为响应,得出模型的传递函数; Model the lithium-ion battery, take the current passing through the model as the excitation I, and the difference between the terminal voltage and the open-circuit voltage of the lithium-ion battery as the response, and obtain the transfer function of the model;

当采样频率很高的时候,将该传递函数用双线性变换法进行离散化,得出差分方程,同时将差值转换为端电压和开路电压的值。 When the sampling frequency is very high, the transfer function is discretized with bilinear transformation method to obtain the difference equation, and the difference is converted into the value of terminal voltage and open circuit voltage at the same time.

进一步地,步骤四中,根据步骤三所算出的信息矩阵,通过锂离子电池的开路电压值,根据步骤二所存储的开路电压和SOC曲线关系,通过曲线图,并利用计算出的开路电压值,插值得出锂离子电池此时的SOC。 Further, in step 4, according to the information matrix calculated in step 3, through the open circuit voltage value of the lithium-ion battery, according to the relationship between the open circuit voltage and the SOC curve stored in step 2, through the graph, and using the calculated open circuit voltage value , interpolation to obtain the SOC of the lithium-ion battery at this time.

进一步地,步骤五中,控制该双向反激式DCDC转换器,一头连着锂离子电池单体,另一头连着多块锂离子电池所连起来的锂离子形成的锂离子电池组,通过MOS管的开断实现锂离子电池能量的转移,并通过线圈上的精密电阻测出锂离子电池所转移的电流,实现针对锂离子电池能量转移的电流控制,同时通过时间控制,实现锂离子电池能量转移的时间的长短,通过对开关频率和时间的长短,实现锂离子电池的电流大小和时间的控制。 Further, in step five, the bidirectional flyback DCDC converter is controlled, one end is connected to a lithium-ion battery cell, and the other end is connected to a lithium-ion battery pack formed by lithium ions connected by multiple lithium-ion batteries, through the MOS The switching of the tube realizes the energy transfer of the lithium-ion battery, and the current transferred by the lithium-ion battery is measured through the precision resistance on the coil, and the current control for the energy transfer of the lithium-ion battery is realized. At the same time, the energy of the lithium-ion battery is realized through time control. The length of the transfer time realizes the control of the current size and time of the lithium-ion battery through the switching frequency and the length of time.

进一步地,控制锂离子电池能量转移的时间由模糊控制器确定,该模糊控 制器为单变量二维模糊控制器。 Further, the time for controlling the energy transfer of the lithium-ion battery is determined by a fuzzy controller, which is a single-variable two-dimensional fuzzy controller.

与现有技术相比,本发明一种锂离子电池能量均衡系统及其实现方法,在能量均衡转移的过程中通过锂离子电池的SOC的估算,以此SOC为依据通过控制DCDC实现均衡,使得系统避免了电压均衡的方式所造成的误均衡,可靠性更高。 Compared with the prior art, the present invention provides a lithium-ion battery energy balance system and its implementation method. In the process of energy balance transfer, the SOC of the lithium-ion battery is estimated, and the SOC is used as a basis to achieve balance by controlling DCDC, so that The system avoids the false balance caused by the voltage balance method, and has higher reliability.

附图说明 Description of drawings

图1为本发明一种锂离子电池能量均衡系统的系统结构图; Fig. 1 is the system structural diagram of a kind of lithium-ion battery energy balance system of the present invention;

图2为本发明较佳实施例中双向同步反激式DCDC转换器的结构示意图; Fig. 2 is a schematic structural view of a bidirectional synchronous flyback DCDC converter in a preferred embodiment of the present invention;

图3为本发明一种锂离子电池能量均衡的实现方法的步骤流程图; Fig. 3 is a flow chart of steps of a method for realizing energy balance of a lithium-ion battery in the present invention;

图4为本发明较佳实施例中对锂离子电池的二阶RC模型离散化示意图; Fig. 4 is the discretization schematic diagram to the second-order RC model of lithium-ion battery in the preferred embodiment of the present invention;

图5为本发明较佳实施例中计算锂离子电池的SOC所利用的曲线图; Fig. 5 is the graph that the SOC of calculating lithium-ion battery utilizes in the preferred embodiment of the present invention;

图6为本发明较佳实施例中模糊控制器所选择的三角隶属度函数示意图; Fig. 6 is a schematic diagram of the triangular membership function selected by the fuzzy controller in a preferred embodiment of the present invention;

图7为本发明一种锂离子电池能量均衡的实现方法之具体实施例的流程图。 FIG. 7 is a flow chart of a specific embodiment of a method for realizing energy balance of a lithium-ion battery according to the present invention.

具体实施方式 Detailed ways

以下通过特定的具体实例并结合附图说明本发明的实施方式,本领域技术人员可由本说明书所揭示的内容轻易地了解本发明的其它优点与功效。本发明亦可通过其它不同的具体实例加以施行或应用,本说明书中的各项细节亦可基于不同观点与应用,在不背离本发明的精神下进行各种修饰与变更。 The implementation of the present invention is described below through specific examples and in conjunction with the accompanying drawings, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific examples, and various modifications and changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

图1为本发明一种锂离子电池能量均衡系统的系统结构图。如图1所示,本发明一种锂离子电池能量均衡系统,包括:锂离子电池组10、n个电压检测电路20、n个DCDC转换器30、n个主控芯片40、电流检测电路50、数据处理芯片60以及CAN通讯模块 Fig. 1 is a system structure diagram of a lithium-ion battery energy equalization system according to the present invention. As shown in FIG. 1 , a lithium-ion battery energy balance system of the present invention includes: a lithium-ion battery pack 10, n voltage detection circuits 20, n DCDC converters 30, n main control chips 40, and a current detection circuit 50 , data processing chip 60 and CAN communication module

锂离子电池组10由n块锂离子电池单体(Cell1,Cell2,……Celln)串联组成,每个锂离子电池单体连接一电压检测电路20,电压检测电路20用于采集锂离子 电池组中每节锂离子电池单体的电压,并将采样值传送至各主控芯片40,即第k个电压检测电路20的输入端分别连接第k个锂离子电池单体的正极和负极,并于需要进行电压检测时开始采样,其采样值经隔离后被传送至第k组主控芯片;每个锂离子电池单体还连接一DCDC转换器30,各DCDC转换器30通过控制MOS管的开关,能够分别对锂离子电池组内各锂离子电池单体直接进行充电和放电,同时通过开关频率调节平衡电流,每个DCDC转换器均独立其他的DCDC,每个DCDC转换器的一端连接锂离子电池单体,另一端连接锂离子电池组。 The lithium-ion battery pack 10 is composed of n lithium-ion battery cells (Cell1, Cell2, ... Celln) connected in series, each lithium-ion battery cell is connected to a voltage detection circuit 20, and the voltage detection circuit 20 is used to collect lithium-ion battery cells The voltage of each lithium-ion battery cell in the battery cell, and the sampled value is sent to each main control chip 40, that is, the input terminal of the kth voltage detection circuit 20 is respectively connected to the positive pole and the negative pole of the k-th lithium-ion battery cell, and Sampling starts when voltage detection is required, and the sampled value is transmitted to the kth group of main control chips after isolation; each lithium-ion battery cell is also connected to a DCDC converter 30, and each DCDC converter 30 controls the MOS tube The switch can directly charge and discharge each lithium-ion battery cell in the lithium-ion battery pack, and at the same time adjust the balance current through the switching frequency. Each DCDC converter is independent of other DCDCs. One end of each DCDC converter is connected to the lithium-ion battery. An ion battery cell, and the other end is connected to a lithium-ion battery pack.

在本发明较佳实施例中,DCDC转换器30采用了双向同步反激式DCDC转换器。图2为本发明较佳实施例中双向同步反激式DCDC转换器的结构示意图。具体地说,第k个双向同步反激式DCDC包括高频变压器Tk、初级开关管Qkp、次级开关管Qks,初级开关管Qkp的源极连接至锂离子电池单体Cellk的负极,初级开关管Qkp的漏极连接至高频变压器Tk的初级之一端,高频变压器Tk的初级之另一端连接至锂离子电池单体Cellk的正极,次级开关管Qks的源极连接至锂离子电池组的负极,次级开关管Qks的漏极连接至高频变压器Tk的次级之一端,高频变压器Tk的次级之另一端连接至锂离子电池组的正极。 In a preferred embodiment of the present invention, the DCDC converter 30 adopts a bidirectional synchronous flyback DCDC converter. FIG. 2 is a schematic structural diagram of a bidirectional synchronous flyback DCDC converter in a preferred embodiment of the present invention. Specifically, the k-th bidirectional synchronous flyback DCDC includes a high-frequency transformer Tk, a primary switching tube Qkp, and a secondary switching tube Qks. The source of the primary switching tube Qkp is connected to the negative pole of the lithium-ion battery cell Cellk, and the primary switch The drain of the tube Qkp is connected to one end of the primary of the high-frequency transformer Tk, the other end of the primary of the high-frequency transformer Tk is connected to the positive pole of the lithium-ion battery cell Cellk, and the source of the secondary switching tube Qks is connected to the lithium-ion battery pack The negative pole of the secondary switching tube Qks is connected to one end of the secondary side of the high-frequency transformer Tk, and the other end of the secondary side of the high-frequency transformer Tk is connected to the positive pole of the lithium-ion battery pack.

以给第一块锂离子电池放电为例,当导通初级开关,电流(通过测量绕组上的电压计算出通过的绕组的电流)在DCDC初级绕组中斜坡上升,直到当电流大于平均电流2倍时为止。初级开关随后关断,且存储在DCDC中的能量被转移至次级绕组,从而导致电流在DCDC的次级绕组中流动。次级开关接通将存储在DCDC中次级绕组的能量转移到锂离子电池组中,在通过绕组的电流降为0A为止。一旦次级电流为零时,则次级开关断开且初级开关重新接通,从而重复刚才所述循环。循环往复,能量将会从锂离子电池单体转移至所有连接在次级绕组顶端和底端之间的锂离子电池组,从而对锂离子电池组充电。 Taking the discharge of the first lithium-ion battery as an example, when the primary switch is turned on, the current (the current passing through the winding is calculated by measuring the voltage on the winding) ramps up in the DCDC primary winding until the current is twice the average current until the time. The primary switch is then turned off and the energy stored in the DCDC is transferred to the secondary winding causing current to flow in the secondary winding of the DCDC. Turning on the secondary switch transfers the energy stored in the secondary winding in the DCDC to the Li-ion battery pack until the current through the winding drops to 0A. Once the secondary current is zero, the secondary switch is turned off and the primary switch is turned back on, repeating the cycle just described. Repeating the cycle, energy will be transferred from the Li-ion battery cells to all the Li-ion battery packs connected between the top and bottom of the secondary winding, thereby charging the Li-ion battery packs.

主控芯片40读出各锂离子电池单体对应的电压检测芯片中锂离子电池的电压信息,然后将数据通过CAN总线传递到数据处理芯片60中,数据处理芯片60 通过线性回归的方法计算各个锂离子电池单体的SOC(State of Charge,荷电状态),同时根据模糊控制算法决定是否对锂离子电池组进行均衡,数据处理芯片60将是否需要均衡的信号和如何均衡的信号经过CAN通讯模块70发送给各主控芯片40,各主控芯片40将均衡使能控制信号发送给各锂离子电池单体进行均衡控制,从而对SOC较低的锂离子电池单体进行充电均衡,对SOC较高的锂离子电池单体进行放电均衡;CAN通讯模块主要负责实现主控芯片40与数据处理芯片60的通信;电流检测电路50连接锂离子电池组10与数据处理芯片60,用于检测电池组的均衡电流以开启或关断初级和次级的开关管。 The main control chip 40 reads the voltage information of the lithium-ion battery in the voltage detection chip corresponding to each lithium-ion battery cell, and then transmits the data to the data processing chip 60 through the CAN bus, and the data processing chip 60 calculates the voltage information of each lithium-ion battery through a linear regression method. The SOC (State of Charge, state of charge) of the lithium-ion battery cell, and at the same time decide whether to balance the lithium-ion battery pack according to the fuzzy control algorithm, and the data processing chip 60 will communicate whether and how to balance the signal through CAN communication The module 70 is sent to each main control chip 40, and each main control chip 40 sends an equalization enable control signal to each lithium-ion battery cell for equalization control, thereby charging and balancing the lithium-ion battery cell with a lower SOC, and adjusting the SOC Higher lithium-ion battery cells carry out discharge equalization; the CAN communication module is mainly responsible for realizing the communication between the main control chip 40 and the data processing chip 60; the current detection circuit 50 is connected to the lithium-ion battery pack 10 and the data processing chip 60 for detecting battery The equalizing current of the group turns on or off the primary and secondary switch tubes.

图3为本发明一种锂离子电池能量均衡的实现方法的步骤流程图。如图3所示,本发明一种锂离子电池能量均衡的实现方法,包括如下步骤: FIG. 3 is a flow chart of the steps of a method for realizing energy balance of a lithium-ion battery according to the present invention. As shown in Figure 3, a method for realizing energy balance of a lithium-ion battery of the present invention comprises the following steps:

步骤301,多次采集锂离子电池组中每块电池电压和电流的信息。较佳的,对锂离子电池的电池电压和电流信息提取频率较高,电压和电流信息间隔时间较短,如100Hz。 Step 301, collecting information on the voltage and current of each battery in the lithium-ion battery pack multiple times. Preferably, the battery voltage and current information of the lithium-ion battery is extracted at a relatively high frequency, and the interval between the voltage and current information is relatively short, such as 100 Hz.

步骤302,将每块电池的电压和电流的信息以及电池容量、寿命、开路电压和SOC的非线性曲线关系等信息输入到数据处理芯片中。较佳的,将多次测得的锂离子电池的电压和电流信息输入到数据处理芯片中,并与提前存入的和电池信息有关的数据(如开路电压和SOC的关系)比较后读出开路电压。 Step 302, input the voltage and current information of each battery, battery capacity, service life, nonlinear curve relationship between open circuit voltage and SOC, etc. into the data processing chip. Preferably, the voltage and current information of the lithium-ion battery measured multiple times is input into the data processing chip, and read out after comparing with the data (such as the relationship between open circuit voltage and SOC) stored in advance and the battery information open circuit voltage.

步骤303,将多次所测得的电池电压信号按照电池的二阶RC模型进行离散化,并通过线性回归的方法来对数据进行处理,得出有用矩阵信息,并通过矩阵算出锂离子电池所对应的其他信息等,最主要的是锂离子电池的开路电压。 Step 303, discretize the battery voltage signals measured multiple times according to the second-order RC model of the battery, and process the data through linear regression to obtain useful matrix information, and calculate the lithium-ion battery voltage through the matrix. Corresponding other information, etc., the most important one is the open circuit voltage of the lithium-ion battery.

具体地说,步骤303包括: Specifically, step 303 includes:

首先,根据多次所测得的电压电流信息通过对锂离子电池的二阶RC模型离散化得到对SOC的估算,如图4所示。 First, according to the voltage and current information measured multiple times, the SOC is estimated by discretizing the second-order RC model of the lithium-ion battery, as shown in Figure 4.

然后将锂离子电池模型化,将通过模型的电流作为激励I,锂离子电池的端电压和开路电压之差作为响应,则这时锂离子电池可以作为一个传递函数: Then the lithium-ion battery is modeled, and the current passing through the model is used as the excitation I, and the difference between the terminal voltage and the open circuit voltage of the lithium-ion battery is used as the response, then the lithium-ion battery can be used as a transfer function:

EE. (( sthe s )) == II (( sthe s )) RR ΩΩ ++ II (( sthe s )) (( RR 11 // // 11 sthe s CC 11 )) ++ II (( sthe s )) (( RR 22 // // 11 sthe s CC 22 ))

其中,E为电池锂离子端电路和开路电压差,I为通过绕组的电流,RΩ为欧姆电阻,R1,R2,C1,C2为模型中二阶RC的电阻电容。 Among them, E is the difference between the battery lithium ion terminal circuit and the open circuit voltage, I is the current through the winding, R Ω is the ohmic resistance, R 1 , R 2 , C 1 , and C 2 are the resistance and capacitance of the second-order RC in the model.

得出模型的传递函数为: The transfer function of the model is obtained as:

GG (( sthe s )) == EE. (( sthe s )) II (( sthe s )) == RR ΩΩ ++ RR 11 11 ++ RR 11 CC 11 sthe s ++ RR 22 11 ++ RR 22 CC 22 sthe s

其中,E为电池锂离子端电路和开路电压差,I为通过电池的电流,RΩ为欧姆电阻,R1,R2,C1,C2为模型中二阶RC的电阻电容 Among them, E is the difference between the battery lithium ion terminal circuit and the open circuit voltage, I is the current passing through the battery, R Ω is the ohmic resistance, R 1 , R 2 , C 1 , and C 2 are the resistance and capacitance of the second-order RC in the model

当采样频率很高的时候,将上述传递函数用双线性变换法进行离散化,得出差分方程: When the sampling frequency is high, the above transfer function is discretized by the bilinear transformation method to obtain the difference equation:

E(k)=a1E(k-1)+a2E(k-2)+a3I(k)+a4I(k-1)+a5I(k-2)  E(k)=a 1 E(k-1)+a 2 E(k-2)+a 3 I(k)+a 4 I(k-1)+a 5 I(k-2)

E为电池锂离子端电路和开路电压差,I为通过电池的电流,a1,a2,a3,a4,a5为离散化后的系数。 E is the difference between the battery lithium ion terminal circuit and the open circuit voltage, I is the current passing through the battery, a1, a2, a3, a4, a5 are the coefficients after discretization.

同时将差值转换为端电压和开路电压的值,由于采样时间较快,开路电压近似,可得: At the same time, the difference is converted to the value of the terminal voltage and the open circuit voltage. Since the sampling time is fast, the open circuit voltage is approximate, and it can be obtained:

V(k)=θ1V(k-1)+θ2V(k-2)+θ3I(k)+θ4I(k-1)+θ5I(k-2)+θ6 V(k)=θ 1 V(k-1)+θ 2 V(k-2)+θ 3 I(k)+θ 4 I(k-1)+θ 5 I(k-2)+θ 6

令: make:

θθ == θθ 11 θθ 22 θθ 33 θθ 44 θθ 55 θθ 66 TT

Xx (( kk )) == VV (( kk -- 11 )) VV (( kk -- 22 )) II (( kk )) II (( kk -- 11 )) II (( kk -- 22 )) 11

则上式可写成多元矩阵乘法的形式: Then the above formula can be written in the form of multivariate matrix multiplication:

V(k)=XT(k)θ V(k)=X T (k)θ

上述 θ = θ 1 θ 2 θ 3 θ 4 θ 5 θ 6 T 值的求取由于为多元矩阵乘法的形式,通过多元线性回归法算出矩阵,即若对于Y=XZ,则Z=(XTX)-1XTY。 the above θ = θ 1 θ 2 θ 3 θ 4 θ 5 θ 6 T The calculation of the value is in the form of multivariate matrix multiplication, and the matrix is calculated by multiple linear regression method, that is, if Y=XZ, then Z=(X T X) -1 X T Y.

通过线性回归计算出信息矩阵后,并通过公式的计算,主要算出锂离子电 池的开路电压OCV,同时得出锂离子电池的其他信息: After calculating the information matrix through linear regression, and through the calculation of the formula, the open circuit voltage OCV of the lithium-ion battery is mainly calculated, and other information about the lithium-ion battery is obtained at the same time:

OCV(k)=θ6/[1-(a1+a2)+a1a2]=θ6/(1-θ12) OCV(k)=θ 6 /[1-(a 1 +a 2 )+a 1 a 2 ]=θ 6 /(1-θ 12 )

aa 11 == (( θθ 11 ++ θθ 11 22 ++ 44 θθ 22 )) // 22

aa 22 == (( θθ 11 -- θθ 11 22 ++ 44 θθ 22 )) // 22

bb 11 == (( θθ 33 aa 11 22 ++ θθ 44 aa 11 ++ θθ 55 )) // (( aa 11 -- aa 22 ))

bb 22 == (( θθ 33 aa 22 22 ++ θθ 44 aa 22 ++ θθ 55 )) // (( aa 11 -- aa 22 ))

RΩ=-θ3 -θ3

R1=b1/(1-a1) R 1 =b 1 /(1-a 1 )

C1=-T/(R1lna1) C 1 =-T/(R 1 lna 1 )

R2=b2/(1-a2) R 2 =b 2 /(1-a 2 )

其中,OCV为开路电压,θ16为刚才回归所求的θ矩阵的值,a1,a2,a3,a4,a5为离散化后的系数,RΩ为欧姆电阻,R1,R2,C1,C2为模型中二阶RC的电阻电容。 Among them, OCV is the open circuit voltage, θ 16 is the value of the θ matrix obtained by the regression just now, a1, a2, a3, a4, a5 are the coefficients after discretization, R Ω is the ohmic resistance, R 1 , R 2 , C 1 , C 2 are the resistance and capacitance of the second-order RC in the model.

步骤304,根据所计算出的电池的开路电压,通过锂离子电池的开路电压和SOC关系曲线插值出锂离子电池的SOC,并计算电池组的平均SOC。 Step 304 , according to the calculated open circuit voltage of the battery, the SOC of the lithium ion battery is interpolated through the relationship curve between the open circuit voltage and the SOC of the lithium ion battery, and the average SOC of the battery pack is calculated.

具体地说,根据步骤303所算出的信息矩阵,通过锂离子电池的开路电压值,根据步骤302所存储的开路电压和SOC曲线关系,通过如图5所示的曲线图,利用计算出的开路电压值,插值可以得出锂离子电池此时的SOC。 Specifically, according to the information matrix calculated in step 303, through the open circuit voltage value of the lithium ion battery, according to the relationship between the open circuit voltage and the SOC curve stored in step 302, through the graph shown in Figure 5, using the calculated open circuit voltage Voltage value, interpolation can get the SOC of the lithium-ion battery at this time.

步骤305,控制双向反激式DCDC转换器,通过检测DCDC上的电流达到一定的峰值,控制双向反激式DCDC的开关MOS管实现锂离子电池组中的电流的通断,从而实现锂离子电池能量转移。 Step 305, control the bidirectional flyback DCDC converter, by detecting that the current on the DCDC reaches a certain peak value, control the switching MOS tube of the bidirectional flyback DCDC to realize the on-off of the current in the lithium-ion battery pack, thereby realizing the lithium-ion battery energy transfer.

具体地说,控制双向反激式DCDC转换器,一头连着锂离子电池单体,另一头连着多块锂离子电池所连起来的锂离子形成的锂离子电池组,通过MOS管的开断实现锂离子电池能量的转移,并通过线圈上的精密电阻测出锂离子电池所转移的电流,实现针对锂离子电池能量转移的电流控制,同时通过时间控制,实现锂离子电池能量转移的时间的长短,通过对开关频率和时间的长短,实现 锂离子电池的电流大小和时间的控制。 Specifically, to control the bidirectional flyback DCDC converter, one end is connected to a lithium-ion battery cell, and the other end is connected to a lithium-ion battery pack formed by lithium ions connected by multiple lithium-ion batteries, through the disconnection of the MOS tube Realize the transfer of lithium-ion battery energy, and measure the current transferred by the lithium-ion battery through the precise resistance on the coil, realize the current control for the energy transfer of lithium-ion batteries, and realize the timing of the energy transfer time of lithium-ion batteries through time control The length, through the switching frequency and the length of the time, realize the control of the current size and time of the lithium-ion battery.

步骤306、根据模糊控制的方法,将所算出的锂离子电池的SOC判断电池所需要的均衡电流和均衡时间,最后通过步骤305控制均衡DCDC均衡锂离子电池直到电池均衡最终完毕,即所有的锂离子电池的电池的样本差小于2%,否则继续从步骤301开始。 Step 306, according to the method of fuzzy control, the calculated SOC of the lithium-ion battery is used to determine the equalization current and equalization time required by the battery, and finally the balanced DCDC balanced lithium-ion battery is controlled through step 305 until the battery equalization is finally completed, that is, all lithium-ion batteries The battery sample difference of the ion battery is less than 2%, otherwise continue to start from step 301 .

控制锂离子电池能量转移的时间主要由模糊控制确定,本发明所使用的模糊控制器是单变量二维模糊控制器,即两个输入一个输出。模糊控制器的输入需要能够准确反映电池组和所需要均衡的电池的关系状态,因此,根据现实情况选择的模糊控制器的输入为电池组平均SOC与所需均衡电池的SOC的差值电池组的平均SOC作为输入。较大的差值意味着需要较长的均衡时间达到均衡的目的,较小时则反之。当平均SOC接近充电或放电状态时,则均衡时间长,以达到快速均衡的效果,防止电池过充过放,当平均SOC在中间状态时,则可以慢速均衡以达到均衡更好的效果。通过下表1所示的模糊控制知识库,选择三角形作为隶属度函数的形状(如图6所示),模糊控制器的输出为控制均衡电路中的均衡时间T和均衡电流I,控制DCDC转换器的开关时间来达到控制均衡效果。 The time for controlling the energy transfer of the lithium-ion battery is mainly determined by fuzzy control, and the fuzzy controller used in the present invention is a single-variable two-dimensional fuzzy controller, that is, two inputs and one output. The input of the fuzzy controller needs to be able to accurately reflect the relationship between the battery pack and the battery to be balanced. Therefore, the input of the fuzzy controller selected according to the actual situation is the difference between the average SOC of the battery pack and the SOC of the battery pack to be balanced. The average SOC of is taken as input. A larger difference means that a longer equalization time is required to achieve the purpose of equalization, and a smaller one means the opposite. When the average SOC is close to the charging or discharging state, the equalization time is long to achieve fast equalization effect and prevent the battery from overcharging and over-discharging. When the average SOC is in the middle state, slow equalization can be used to achieve better equalization effect. Through the fuzzy control knowledge base shown in Table 1 below, a triangle is selected as the shape of the membership function (as shown in Figure 6). The output of the fuzzy controller is to control the equalization time T and the equalization current I in the equalization circuit, and to control the DCDC conversion Switching time of the switch to achieve the control balance effect.

表1模糊控制知识库 Table 1 Fuzzy control knowledge base

图7为本发明一种锂离子电池能量均衡的实现方法之具体实施例的流程图。如图7所示,本发明通过对锂离子电池进行充放电,采集锂离子电池的电压、电流。研究锂离子电池的电压特性和SOC特性。包括OCV(开路电压)和SOC的关系曲线,电池的内阻和电池的SOC的关系曲线,观察锂离子电池性能曲线。 然后将锂离子电池电压电流数据传入数据处理板中。通过二阶RC模型的差分方程,通过线性回归方程计算锂离子电池当时的开路电压,并通过插值法算出锂离子电池那时的SOC。然后算出锂离子电池组的平均SOC。计算锂离子电池组的电池分散度,判断电池分散度是否大于2%。如果电池分散度小于2%时,继续从检测锂离子电池电压开始。若锂离子电池分散度大于2%时,则通过模糊控制法来判断均衡电流和均衡时间。得出锂离子电池组的均衡电流和均衡时间后,通过控制DCDC转换器,使得锂离子电池均衡得到控制,直到电池分散度小于2%。 FIG. 7 is a flow chart of a specific embodiment of a method for realizing energy balance of a lithium-ion battery according to the present invention. As shown in FIG. 7 , the present invention collects the voltage and current of the lithium ion battery by charging and discharging the lithium ion battery. Study the voltage characteristics and SOC characteristics of lithium-ion batteries. Including the relationship curve between OCV (open circuit voltage) and SOC, the relationship curve between the internal resistance of the battery and the SOC of the battery, and observe the performance curve of the lithium-ion battery. Then the lithium-ion battery voltage and current data are transmitted to the data processing board. Through the differential equation of the second-order RC model, the open circuit voltage of the lithium-ion battery at that time is calculated through the linear regression equation, and the SOC of the lithium-ion battery at that time is calculated by the interpolation method. Then calculate the average SOC of the lithium-ion battery pack. Calculate the battery dispersion degree of the lithium-ion battery pack, and judge whether the battery dispersion degree is greater than 2%. If the battery dispersion is less than 2%, continue to start from detecting the lithium-ion battery voltage. If the dispersion of lithium-ion batteries is greater than 2%, the balance current and balance time are judged by the fuzzy control method. After obtaining the balance current and balance time of the lithium-ion battery pack, the balance of the lithium-ion battery is controlled by controlling the DCDC converter until the battery dispersion is less than 2%.

综上所述,本发明一种锂离子电池能量均衡系统及其实现方法,在能量均衡转移的过程中通过锂离子电池的SOC的估算,以此SOC为依据通过控制DCDC实现均衡,使得系统避免了电压均衡的方式所造成的误均衡,可靠性更高。 In summary, the present invention provides a lithium-ion battery energy balance system and its implementation method. In the process of energy balance transfer, the SOC of the lithium-ion battery is estimated, and the SOC is used as a basis to achieve balance by controlling DCDC, so that the system avoids The misbalance caused by the voltage equalization method is eliminated, and the reliability is higher.

上述实施例仅例示性说明本发明的原理及其功效,而非用于限制本发明。任何本领域技术人员均可在不违背本发明的精神及范畴下,对上述实施例进行修饰与改变。因此,本发明的权利保护范围,应如权利要求书所列。 The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Any person skilled in the art can modify and change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be listed in the claims.

Claims (10)

1. a lithium ion battery balancing energy system, comprising:
Li-ion batteries piles, described Li-ion batteries piles is composed in series by n block lithium-ion battery monomer, and each lithium-ion battery monomer connects a voltage detecting circuit and a DC-DC converter;
N voltage detecting circuit, the input of a kth voltage detecting circuit connects positive pole and the negative pole of a kth lithium-ion battery monomer respectively, and when needs carry out voltage detecting, start sampling, and its sampled value is transferred into kth group main control chip after isolation;
N DC-DC converter, each DC-DC converter, by controlling the switch of metal-oxide-semiconductor, directly carries out charging and discharging to lithium-ion battery monomer each in Li-ion batteries piles respectively, simultaneously by switching frequency adjustment electric current;
N main control chip, each main control chip reads the information of voltage of lithium ion battery in voltage detecting circuit corresponding to each lithium-ion battery monomer, is then delivered in data processing chip 60 by data by CAN;
Data processing chip, the SOC of each lithium-ion battery monomer is calculated by the method for linear regression, determine whether equilibrium is carried out to Li-ion batteries piles according to FUZZY ALGORITHMS FOR CONTROL simultaneously, equalizing signal is sent to each main control chip through CAN communication module by data processing chip 60, and enable for equilibrium control signal sends to each lithium-ion battery monomer to carry out Balance route by each main control chip;
CAN communication module, is responsible for the communication realizing described main control chip and described data processing chip;
Current detection circuit, connects described Li-ion batteries piles and data processing chip, for detecting the euqalizing current of battery pack to open or to turn off the switching tube of primary and secondary.
2. a kind of lithium ion battery balancing energy system as claimed in claim 1, it is characterized in that: described DC-DC converter adopts bi-directional synchronization inverse-excitation type DC-DC converter, each DC-DC converter other DCDC all independent, one end of each DC-DC converter connects lithium-ion battery monomer, and the other end connects Li-ion batteries piles.
3. a kind of lithium ion battery balancing energy system as claimed in claim 2, it is characterized in that: a kth bi-directional synchronization inverse-excitation type DCD transducer comprises high frequency transformer (Tk), primary switch pipe (Qkp), secondary switch pipe (Qks), the source electrode of primary switch pipe (Qkp) is connected to the negative pole of lithium-ion battery monomer (Cellk), the drain electrode of primary switch pipe (Qkp) is connected to elementary one end of high frequency transformer (Tk), the elementary other end of high frequency transformer (Tk) is connected to the positive pole of lithium-ion battery monomer (Cellk), the source electrode of secondary switch pipe (Qks) is connected to the negative pole of this Li-ion batteries piles, the drain electrode of secondary switch pipe (Qks) is connected to secondary one end of high frequency transformer (Tk), the secondary other end of high frequency transformer (Tk) is connected to the positive pole of Li-ion batteries piles.
4. an implementation method for lithium ion battery balancing energy, comprises the steps:
Step one, the information of every block cell voltage and electric current in multi collect Li-ion batteries piles;
Step 2, is input in data processing chip by the nonlinear curve relation information of the information of the voltage and current of every block battery and battery capacity, life-span, open circuit voltage and SOC;
Step 3, repeatedly measured battery voltage signal is carried out discretization according to the Order RC model of battery, and by the method for linear regression, data are processed, draw useful matrix information, and calculate the open circuit voltage corresponding to lithium ion battery by matrix;
Step 4, according to the open circuit voltage of calculated battery, is gone out the SOC of lithium ion battery, and calculates the average SOC of battery pack by the open circuit voltage of lithium ion battery and SOC relation curve interpolation;
Step 5, according to the method for fuzzy control, judges the euqalizing current required for battery and time for balance by the SOC of calculated lithium ion battery;
Step 6, controls two-way inverse-excitation type DC-DC converter, and reach certain peak value by the electric current detected on DCDC, the switch MOS pipe controlling two-way inverse-excitation type DCDC realizes the break-make of the electric current in Li-ion batteries piles, thus realizes lithium ion battery energy trasfer.
5. the implementation method of a kind of lithium ion battery balancing energy as claimed in claim 4, is characterized in that, after step 4, also comprise the steps:
Calculate the battery decentralization of Li-ion batteries piles;
Judge whether battery decentralization is greater than predetermined threshold;
If when battery decentralization is less than this predetermined threshold, then enters step one and continue to press off the beginning from detection lithium ion battery battery; If when lithium ion battery decentralization is greater than this predetermined threshold, then enter step 5.
6. the implementation method of a kind of lithium ion battery balancing energy as claimed in claim 5, is characterized in that: in step one, and extract frequency to the cell voltage of lithium ion battery and current information higher, the voltage and current information interval time is shorter.
7. the implementation method of a kind of lithium ion battery balancing energy as claimed in claim 6, it is characterized in that, step 3 comprises the steps:.
According to repeatedly measured electric current and voltage information by obtaining the estimation to SOC to the Order RC model discretization of lithium ion battery;
By Li-ion battery model, using the electric current by model as excitation I, the terminal voltage of lithium ion battery and the difference of open circuit voltage responsively, draw the transfer function of model;
When sample frequency is very high time, this transfer function Bilinear transformation method is carried out discretization, draws difference equation, difference is converted to the value of terminal voltage and open circuit voltage simultaneously.
8. the implementation method of a kind of lithium ion battery balancing energy as claimed in claim 6, it is characterized in that: in step 4, according to the information matrix that step 3 calculates, by the open-circuit voltage values of lithium ion battery, the open circuit voltage stored according to step 2 and SOC curved line relation, by curve chart, and utilize the open-circuit voltage values calculated, interpolation draws lithium ion battery SOC now.
9. the implementation method of a kind of lithium ion battery balancing energy as claimed in claim 6, it is characterized in that: in step 5, control this two-way inverse-excitation type DC-DC converter, a lithium-ion battery monomer of ining succession, in succession the Li-ion batteries piles that lithium ion that polylith lithium ion battery links up is formed in other end, the transfer realizing lithium ion battery energy is cut-off by metal-oxide-semiconductor, and measure by the precision resistance on coil the electric current that lithium ion battery shifts, realize the Current Control for lithium ion battery energy trasfer, pass through time controling simultaneously, realize the length of the time of lithium ion battery energy trasfer, by the length to switching frequency and time, realize the size of current of lithium ion battery and the control of time.
10. the implementation method of a kind of lithium ion battery balancing energy as claimed in claim 9, is characterized in that: the time controlling lithium ion battery energy trasfer is determined by fuzzy controller, and this fuzzy controller is single argument two-dimensional fuzzy controller.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110089898A1 (en) * 2008-04-22 2011-04-21 Sk Energy Co., Ltd. Two-Stage Charge Equalization Method and Apparatus for Series-Connected Battery String
CN203660584U (en) * 2013-12-06 2014-06-18 淄博明泰电器科技有限公司 Modularization battery equalization and charging system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110089898A1 (en) * 2008-04-22 2011-04-21 Sk Energy Co., Ltd. Two-Stage Charge Equalization Method and Apparatus for Series-Connected Battery String
CN203660584U (en) * 2013-12-06 2014-06-18 淄博明泰电器科技有限公司 Modularization battery equalization and charging system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
李成学等: "电动汽车蓄电池组电池管理及其状态检测", 《电源技术》 *

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