CN108091945B - A kind of voltage monitoring method, method for estimating state and the device of liquid metal cell - Google Patents
A kind of voltage monitoring method, method for estimating state and the device of liquid metal cell Download PDFInfo
- Publication number
- CN108091945B CN108091945B CN201711259522.3A CN201711259522A CN108091945B CN 108091945 B CN108091945 B CN 108091945B CN 201711259522 A CN201711259522 A CN 201711259522A CN 108091945 B CN108091945 B CN 108091945B
- Authority
- CN
- China
- Prior art keywords
- liquid metal
- voltage
- metal battery
- adjacent
- group
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910001338 liquidmetal Inorganic materials 0.000 title claims abstract description 193
- 238000000034 method Methods 0.000 title claims abstract description 44
- 238000012544 monitoring process Methods 0.000 title claims abstract description 31
- 238000005259 measurement Methods 0.000 claims abstract description 28
- 239000002184 metal Substances 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 238000001514 detection method Methods 0.000 abstract description 7
- 239000011159 matrix material Substances 0.000 description 13
- 230000000694 effects Effects 0.000 description 6
- 238000012806 monitoring device Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000006872 improvement Effects 0.000 description 5
- 230000007547 defect Effects 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 238000004146 energy storage Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 238000012983 electrochemical energy storage Methods 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910001416 lithium ion Inorganic materials 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Secondary Cells (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
本发明公开了一种液态金属电池的电压监测方法、状态估计方法及检测装置，包括如下步骤：从N个串联的液态金属电池中选出L组第一相邻液态金属电池组，并获得L组第一相邻液态金属电池组的端电压；从N个串联的液态金属电池中选出K组第二相邻液态金属电池组，并获得K组第二相邻液态金属电池组的端电压；将上述L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压表示为每个液态金属电池电压的和，形成初始电压方程组；将初始电压方程组进行去冗余处理获得系数满秩的电压方程组；根据系数满秩的电压方程组计算获得每个液态金属电池电压。该方法能有效降低低电压、宽平台液态金属电池单体的电压测量误差，提高状态估计精度。
The invention discloses a liquid metal battery voltage monitoring method, a state estimation method and a detection device, comprising the following steps: selecting L groups of first adjacent liquid metal battery groups from N liquid metal batteries connected in series, and obtaining L The terminal voltage of the first adjacent liquid metal battery pack of the group; select the second adjacent liquid metal battery pack of K group from N liquid metal batteries connected in series, and obtain the terminal voltage of the second adjacent liquid metal battery pack of K group ; The terminal voltage of the first adjacent liquid metal battery pack of the above-mentioned L group and the terminal voltage of the second adjacent liquid metal battery pack of the K group are expressed as the sum of each liquid metal battery voltage, forming an initial voltage equation group; the initial voltage The equations are deredundantly processed to obtain the voltage equations with full ranks of coefficients; the voltage of each liquid metal battery is obtained by calculating the voltage equations with full ranks of coefficients. This method can effectively reduce the voltage measurement error of a low-voltage, wide-platform liquid metal battery cell and improve the accuracy of state estimation.
Description
技术领域technical field
本发明涉及二次电池应用技术领域，更具体地，涉及一种液态金属电池的电压监测方法、状态估计方法及装置。The present invention relates to the technical field of secondary battery application, and more specifically, to a voltage monitoring method, a state estimation method and a device for a liquid metal battery.
背景技术Background technique
大规模储能是有效提高可再生能源发电入网的关键技术。液态金属电池作为新近发展起来的一类电化学储能技术，三层液态结构的设计，采用无机熔盐和液态金属作为电解质和正负极，具有成本低、容量大、效率高、寿命长等特点，在规模储能领域具有广阔的应用前景。然而由于电池单体容量和电压的限制，实际应用中电池单体通过串并联成组实现容量放大和电压提升，电池组单元通过电池管理系统(Battery Management System,BMS)进行统一的能量管理与控制，其主要功能包括：电池物理参数的实时监测，电池的状态估计，在线诊断与预警，充放电控制以及均衡管理和热管理等。这些功能的实现依赖于对电池物理量的精确测量，即电压和电流。对于新型液态金属电池而言，其单体电池电压平台低且宽特性，使得依赖于电压精度的状态估计和均衡控制陷入困难。Large-scale energy storage is a key technology to effectively increase the access of renewable energy power generation to the grid. As a newly developed electrochemical energy storage technology, liquid metal batteries are designed with a three-layer liquid structure, using inorganic molten salts and liquid metals as electrolytes and positive and negative electrodes, and have the characteristics of low cost, large capacity, high efficiency, and long life. It has broad application prospects in the field of large-scale energy storage. However, due to the limitation of battery cell capacity and voltage, in practical applications, the battery cells are connected in series and parallel to achieve capacity amplification and voltage improvement, and the battery pack units perform unified energy management and control through the battery management system (Battery Management System, BMS). , its main functions include: real-time monitoring of battery physical parameters, battery state estimation, online diagnosis and early warning, charge and discharge control, balance management and thermal management, etc. The realization of these functions depends on the accurate measurement of the physical quantities of the battery, namely voltage and current. For the new liquid metal battery, the low and wide voltage platform of the single battery makes it difficult to estimate the state and balance control that depend on voltage accuracy.
在中国发明专利说明书CN106654413A中公开了一种液态金属电池组的多级均衡控制系统和方法，通过主、被动均衡相结合，提高了液态金属电池组均衡效率，也解决了液态金属电池单体电压平台低，主动均衡实施难的问题，但是其被动均衡采用监测电池单体电压进行荷电状态(State of Charge,SOC)估计,并以SOC作为均衡变量，对于液态金属电池而言，单体电池电压平台平坦、数值低(0.9V)，电池电压测量误差对状态估计影响大，因此实际应用中效果不理想。In the Chinese invention patent specification CN106654413A, a multi-level equalization control system and method for a liquid metal battery pack is disclosed. Through the combination of active and passive equalization, the equalization efficiency of the liquid metal battery pack is improved, and the liquid metal battery cell voltage is also solved. The platform is low, and the implementation of active equalization is difficult, but its passive equalization uses the monitoring of battery cell voltage to estimate the state of charge (SOC), and uses SOC as the balance variable. For liquid metal batteries, the single battery The voltage platform is flat and the value is low (0.9V), and the battery voltage measurement error has a great influence on the state estimation, so the effect is not ideal in practical applications.
由于存在上述缺陷与不足，本领域亟需做出进一步的完善和改进，针对液态金属电池低电压、宽平台的特点，设计一种有效减小电压测量误差的拓扑与方法，以提高状态估计和均衡控制的精度。Due to the above defects and deficiencies, further improvements and improvements are urgently needed in this field. According to the characteristics of low voltage and wide platform of liquid metal batteries, a topology and method that can effectively reduce voltage measurement errors are designed to improve state estimation and The precision of balance control.
发明内容Contents of the invention
针对上述缺陷，本发明提供了一种液态金属电池的电压监测方法、状态估计方法及装置，旨在解决现有的液态金属电池电压由于不能考虑到液态金属电池低电压、宽平台的特点导致的单体电池电压测量误差大，漂移严重的缺陷。In view of the above defects, the present invention provides a liquid metal battery voltage monitoring method, state estimation method and device, aiming at solving the problem that the existing liquid metal battery voltage cannot take into account the low voltage and wide platform characteristics of the liquid metal battery. The single battery voltage measurement error is large and the defect is serious drift.
为实现上述目的，按照本发明的一个方面，提供了一种液态金属电池的电压监测方法，包括如下步骤：In order to achieve the above object, according to one aspect of the present invention, a voltage monitoring method for a liquid metal battery is provided, comprising the following steps:
从N个串联的液态金属电池中选出L组第一相邻液态金属电池组，并获得L组第一相邻液态金属电池组的端电压；Select the first L group of adjacent liquid metal battery packs from the N liquid metal batteries connected in series, and obtain the terminal voltage of the first L group of adjacent liquid metal battery packs;
从N个串联的液态金属电池中选出K组第二相邻液态金属电池组，并获得K组第二相邻液态金属电池组的端电压；Select K groups of second adjacent liquid metal battery packs from N liquid metal batteries connected in series, and obtain the terminal voltage of the second adjacent liquid metal battery packs of K groups;
将上述L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压表示为每个液态金属电池电压的和，形成初始电压方程组；The terminal voltage of the first adjacent liquid metal battery pack of the above-mentioned L group and the terminal voltage of the second adjacent liquid metal battery pack of the K group are expressed as the sum of each liquid metal battery voltage to form an initial voltage equation group;
将初始电压方程组进行去冗余处理获得系数满秩的电压方程组；The initial voltage equations are deredundantly processed to obtain voltage equations with full rank coefficients;
根据系数满秩的电压方程组获得每个液态金属电池电压；Obtain the voltage of each liquid metal battery according to the voltage equation system with full rank of coefficients;
其中，L+K≥N，2≤M≤(N+1)/2，第一相邻液态金属电池组为相邻M节液态金属电池，第二相邻液态金属电池组为相邻M+1节液态金属电池。Among them, L+K≥N, 2≤M≤(N+1)/2, the first adjacent liquid metal battery group is the adjacent M liquid metal battery, and the second adjacent liquid metal battery group is the adjacent M+ 1 liquid metal battery.
优选地，根据公式获得电压方程组；Preferably, according to the formula Get voltage equations;
其中，Ui为第i组第一相邻液态金属电池组的端电压，Ul为第l组第二相邻液态金属电池组的端电压，Xj为第j个液态金属电池的端电压，aij表示第i组第一相邻液态金属电池组的端电压是否包含第j个液态金属电池的端电压，alj表示第l组第二相邻液态金属电池组的端电压是否包含第j个液态金属电池的端电压，1≤j≤N，1≤i≤L，L+1≤l≤L+K。Among them, U i is the terminal voltage of the first adjacent liquid metal battery pack of the i group, U l is the terminal voltage of the second adjacent liquid metal battery pack of the l group, and X j is the terminal voltage of the jth liquid metal battery , a ij indicates whether the terminal voltage of the first adjacent liquid metal battery pack of the i group includes the terminal voltage of the jth liquid metal battery, a lj indicates whether the terminal voltage of the second adjacent liquid metal battery pack of the l group includes the terminal voltage of the jth liquid metal battery pack Terminal voltage of j liquid metal batteries, 1≤j≤N, 1≤i≤L, L+1≤l≤L+K.
优选地，在本发明中，为了减小常规方法(直接测取低电压的单节液态金属电池端电压)造成的误差，实现本发明所述方法，电池组单元串联的液态金属电池单体数目N应满足，N≥3，且N为整数。Preferably, in the present invention, in order to reduce the error caused by conventional methods (directly measuring the terminal voltage of a single liquid metal battery with low voltage), to realize the method of the present invention, the number of liquid metal battery cells connected in series of battery pack units N should satisfy, N≥3, and N is an integer.
优选地，第一相邻液态金属电池组的端电压的数量可以取L＝N-M+1；第二相邻液态金属电池组的端电压的数量可以取K＝M-1，通过选取L＝N-M+1和K＝M-1，构成的初始电压方程一般为满秩方程，即可满足要求，且所需资源最少。Preferably, the quantity of the terminal voltage of the first adjacent liquid metal battery group can take L=N-M+1; The quantity of the terminal voltage of the second adjacent liquid metal battery group can take K=M-1, by selecting L =N-M+1 and K=M-1, the initial voltage equation formed is generally a full-rank equation, which can meet the requirements and requires the least resources.
作为本发明的另一方面，本发明提供了一种液态金属电池的状态估计方法，包括如下步骤：As another aspect of the present invention, the present invention provides a method for state estimation of a liquid metal battery, comprising the steps of:
根据上述电压检测方法获得搁置状态下液态金属电池单体电压；Obtain the liquid metal battery cell voltage under the shelving state according to the above-mentioned voltage detection method;
根据液态金属电池单体电压和液态金属电池荷电状态与开路电压关系获得液态金属电池单体当前初始荷电状态；According to the voltage of the liquid metal battery cell and the relationship between the state of charge of the liquid metal battery and the open circuit voltage, the current initial state of charge of the liquid metal battery cell is obtained;
根据液态金属电池单体当前初始荷电状态，利用安时积分法对液态金属电池荷电状态进行估计。According to the current initial state of charge of the liquid metal battery cell, the state of charge of the liquid metal battery is estimated by using the ampere-hour integral method.
优选地，根据公式获得液态金属电池荷电状态，其中，Cn为电池容量，i为电流(放电为正值，充电为负值)，SOC0为当前电池的初始荷电状态，当前电池的初始荷电状态根据液态金属电池单体电压和液态金属电池荷电状态与开路电压关系获得。Preferably, according to the formula Obtain the state of charge of the liquid metal battery, wherein, C n is the battery capacity, i is the current (discharging is a positive value, charging is a negative value), SOC 0 is the initial state of charge of the current battery, and the initial state of charge of the current battery is according to The relationship between the liquid metal battery cell voltage and the state of charge of the liquid metal battery and the open circuit voltage is obtained.
作为本发明的另一方面，本发明提供了一种液态金属电池的电压监测系统，包括：As another aspect of the present invention, the present invention provides a voltage monitoring system for a liquid metal battery, comprising:
电压获取模块，用于获取L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压；A voltage acquisition module, configured to acquire the terminal voltage of the first adjacent liquid metal battery pack of L group and the terminal voltage of the second adjacent liquid metal battery pack of K group;
单体电压获取模块，其输入端与电压获取模块的输出端连接，用于根据L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压、相邻电压金属电池组的端电压测量结构获得电压方程组，根据电压方程组获得单个液态金属电池的端电压；A single voltage acquisition module, whose input terminal is connected to the output terminal of the voltage acquisition module, is used to obtain terminal voltages and phases according to the terminal voltage of the first adjacent liquid metal battery pack of the L group and the second adjacent liquid metal battery pack of the K group. The terminal voltage measurement structure of the adjacent voltage metal battery pack obtains the voltage equation group, and obtains the terminal voltage of a single liquid metal battery according to the voltage equation group;
其中，L+K≥N，2≤M≤(N+1)/2，第一相邻液态金属电池组为相邻M节液态金属电池，第二相邻液态金属电池组为相邻M+1节液态金属电池。Among them, L+K≥N, 2≤M≤(N+1)/2, the first adjacent liquid metal battery group is the adjacent M liquid metal battery, and the second adjacent liquid metal battery group is the adjacent M+ 1 liquid metal battery.
通过本发明所构思的以上技术方案，与现有技术相比，能够取得以下Through the above technical solutions conceived in the present invention, compared with the prior art, the following can be obtained
有益效果：Beneficial effect:
1、本发明的液态金属电池的电压监测方法，通过获得L组M个相邻液态金属电池的端电压以及K组M+1个相邻液态金属电池的端电压，通过获得相邻液态金属电池的端电压的测量拓扑，构建初始电压方程组，对初始电压方程进行去冗余处理，获得系数矩阵满秩的电压方程，通过对系数矩阵满秩电压方程组求解，即可获得单体液态金属电池的电压，同时系数矩阵A是稀疏矩阵，计算量小，在测量系统固有精度的基础上，能有效降低低电压、宽平台液态金属电池单体的电压测量误差，从而提供状态估计精度，并易于在微处理器上应用。1. The voltage monitoring method of the liquid metal battery of the present invention, by obtaining the terminal voltage of M adjacent liquid metal batteries of L group and the terminal voltage of M+1 adjacent liquid metal batteries of K group, by obtaining the terminal voltage of adjacent liquid metal batteries Based on the measurement topology of the terminal voltage, the initial voltage equations are constructed, and the initial voltage equations are de-redundantly processed to obtain the voltage equations with a full rank of the coefficient matrix. By solving the full rank voltage equations of the coefficient matrix, the monomer liquid metal can be obtained The voltage of the battery, and the coefficient matrix A is a sparse matrix with a small amount of calculation. On the basis of the inherent accuracy of the measurement system, it can effectively reduce the voltage measurement error of the low-voltage, wide-platform liquid metal battery cell, thereby providing state estimation accuracy, and Ease of application on microprocessors.
2、本发明的液态金属电池的电压监测方法，通过获得N-M+1组M个相邻液态金属电池的端电压以及M-1组M+1个相邻液态金属电池的端电压，通过获得相邻液态金属电池的端电压的测量拓扑，构建电压方程组，由于2≤M≤(N+1)/2，N-M+1组M个相邻液态金属电池的端电压形成的方程和M-1组M+1个相邻液态金属电池的端电压形成的方程不相关，能够保证电压方程组的系数矩阵为满秩，不需要对电压方程组进行去冗余处理。2. The voltage monitoring method of the liquid metal battery of the present invention, by obtaining the terminal voltage of the M adjacent liquid metal batteries of the N-M+1 group and the terminal voltage of the M+1 adjacent liquid metal batteries of the M-1 group, by Obtain the measurement topology of the terminal voltage of the adjacent liquid metal battery, and construct the voltage equation group. Since 2≤M≤(N+1)/2, the equation formed by the terminal voltage of M adjacent liquid metal batteries in the N-M+1 group It is irrelevant to the equations formed by the terminal voltages of M+1 adjacent liquid metal batteries in the M-1 group, which can ensure that the coefficient matrix of the voltage equations is of full rank, and there is no need to de-redundant the voltage equations.
3、本发明对低电压平台的液态金属电池状态估计和均衡管理至关重要，在低电压平台下微小的电压测量误差可能会导致较大的状态估计误差，从而也会影响以状态变量为参考的均衡管理效率，因此本发明提供的荷电状态估计方法中，液态金属电池的端电压能够精确获得，使得液态金属电池的初始荷电状态更精确，进而提高状态估计的精度，将有效解决低电压平台的液态金属电池在电池管理方面遇到的困难。3. The present invention is very important for state estimation and balanced management of liquid metal batteries on low-voltage platforms. Under low-voltage platforms, small voltage measurement errors may lead to large state estimation errors, which will also affect the state variables as a reference. Therefore, in the method for estimating the state of charge provided by the present invention, the terminal voltage of the liquid metal battery can be accurately obtained, so that the initial state of charge of the liquid metal battery is more accurate, thereby improving the accuracy of state estimation, which will effectively solve the problem of low Difficulties encountered in battery management of liquid metal batteries for voltage platforms.
4、本发明的液态金属电池电压监测装置在不改变液态金属电池组单元结构的情况下进行电压测量，与传统直接测量单节电池电压的方法相比，没有增加测量系统的复杂性，同时由于本发明使用多节液态金属电池的端口电压作为测量，选取合适的M值即可，可以直接使用现有锂离子电池电压监测芯片，而不需要专门针对液态金属电池电压平台低且宽的特性再设计相应量程的电池电压监测芯片。4. The liquid metal battery voltage monitoring device of the present invention performs voltage measurement without changing the unit structure of the liquid metal battery pack. Compared with the traditional method of directly measuring the voltage of a single battery, it does not increase the complexity of the measurement system, and at the same time due to The present invention uses the port voltage of multi-cell liquid metal batteries as the measurement, and it is enough to select a suitable M value, and the existing lithium-ion battery voltage monitoring chip can be used directly, without the need to redesign the low and wide characteristics of the liquid metal battery voltage platform. Design a battery voltage monitoring chip with a corresponding range.
附图说明Description of drawings
图1为本发明提供的一种液态金属电池的电压监测方法的流程图；Fig. 1 is the flowchart of the voltage monitoring method of a kind of liquid metal battery provided by the present invention;
图2本发明提供的一种液态金属电池的电压监测方法的实施例的流程图；Fig. 2 is a flowchart of an embodiment of a voltage monitoring method for a liquid metal battery provided by the present invention;
图3为本发明提供的液态金属电池的电压监测装置的结构示意图；Fig. 3 is the structural representation of the voltage monitoring device of the liquid metal battery provided by the present invention;
图4是本发明提供的液态金属电池充放电电压曲线图；Fig. 4 is the charge and discharge voltage curve diagram of the liquid metal battery provided by the present invention;
图5是本发明提供的液态金属电池电压监测方法效果对比图；Fig. 5 is a comparison diagram of the effect of the liquid metal battery voltage monitoring method provided by the present invention;
图6是本发明提供的电压监测方法实施电池状态估计的效果对比图。Fig. 6 is a comparison diagram of the effect of battery state estimation implemented by the voltage monitoring method provided by the present invention.
具体实施方式Detailed ways
为了使本发明的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本发明进行进一步详细说明。应当理解，此处所描述的具体实施例仅用以解释本发明，并不用于限定本发明。In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.
本发明所要解决的技术问题是针对液态金属电池低电压、宽平台的特点导致的单体电池电压测量误差大，漂移严重的缺陷，提供一种简单有效的减小电池电压测量误差，抑制电压漂移的方法，其能够减小液态金属电池电压监测误差，提高电压监测精度，从而给电池管理系统状态估计、均衡控制提供更精确的采样数据，提高状态估计精度以及均衡控制效果。解决液态金属电池电压平台低且宽导致的荷电状态估计和均衡控制困难的问题。The technical problem to be solved by the present invention is to provide a simple and effective method for reducing battery voltage measurement errors and suppressing voltage drift in view of the defects of large single battery voltage measurement errors and serious drift caused by the characteristics of low voltage and wide platform of liquid metal batteries The method can reduce the liquid metal battery voltage monitoring error and improve the voltage monitoring accuracy, thereby providing more accurate sampling data for the battery management system state estimation and balance control, and improving the state estimation accuracy and balance control effect. Solve the problem of difficult state of charge estimation and balance control caused by the low and wide voltage platform of liquid metal batteries.
图1为本发明提供的一种液态金属电池的电压监测方法的流程图；该电压检测方法包括如下步骤：Fig. 1 is the flowchart of the voltage monitoring method of a kind of liquid metal battery provided by the present invention; This voltage detection method comprises the steps:
从N个串联的液态金属电池中选出L组第一相邻液态金属电池组，并获得L组第一相邻液态金属电池组的端电压；Select the first L group of adjacent liquid metal battery packs from the N liquid metal batteries connected in series, and obtain the terminal voltage of the first L group of adjacent liquid metal battery packs;
从N个串联的液态金属电池中选出K组第二相邻液态金属电池组，并获得K组第二相邻液态金属电池组的端电压；Select K groups of second adjacent liquid metal battery packs from N liquid metal batteries connected in series, and obtain the terminal voltage of the second adjacent liquid metal battery packs of K groups;
将上述L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压表示为每个液态金属电池电压的和，形成初始电压方程组；The terminal voltage of the first adjacent liquid metal battery pack of the above-mentioned L group and the terminal voltage of the second adjacent liquid metal battery pack of the K group are expressed as the sum of each liquid metal battery voltage to form an initial voltage equation group;
将初始电压方程组进行去冗余处理获得系数满秩的电压方程组；The initial voltage equations are deredundantly processed to obtain voltage equations with full rank coefficients;
根据系数满秩的电压方程组计算即可获得每个液态金属电池电压；The voltage of each liquid metal battery can be obtained by calculating the voltage equation group with full rank of coefficients;
其中，L+K≥N，2≤M≤(N+1)/2，第一相邻液态金属电池组为相邻M节液态金属电池，第二相邻液态金属电池组为相邻M+1节液态金属电池。Among them, L+K≥N, 2≤M≤(N+1)/2, the first adjacent liquid metal battery group is the adjacent M liquid metal battery, and the second adjacent liquid metal battery group is the adjacent M+ 1 liquid metal battery.
为了减小常规方法造成的误差，即直接测取低电压的单节液态金属电池端电压造成的误差，实现本发明所述方法，电池组单元串联的液态金属电池单体数目N应满足，N≥3。In order to reduce the error caused by conventional methods, that is, the error caused by directly measuring the terminal voltage of a single liquid metal battery with low voltage, to realize the method of the present invention, the number N of liquid metal battery cells connected in series with battery pack units should satisfy, N ≥3.
图2本发明提供的一种液态金属电池的电压监测方法的实施例的流程图；图3为本发明提供的液态金属电池的电压监测装置的结构示意图；电压监测方法的实施例包括如下步骤：Fig. 2 is the flowchart of the embodiment of the voltage monitoring method of a kind of liquid metal battery provided by the present invention; Fig. 3 is the structural representation of the voltage monitoring device of the liquid metal battery provided by the present invention; The embodiment of voltage monitoring method comprises the following steps:
步骤1：从电压测量模块依次获取所有相邻M节液态金属电池端口电压，共N-M+1组电压，记U1，U2，…，UN-M+1；即令L＝N-M+1。Step 1: Obtain the port voltages of all adjacent M liquid metal batteries sequentially from the voltage measurement module, a total of N-M+1 groups of voltages, denote U 1 , U 2 ,..., U N-M+1 ; that is, let L=N- M+1.
步骤2：根据电压测量的拓扑结构，确定测量端口电压的成分：Step 2: According to the topology of the voltage measurement, determine the composition of the voltage at the measurement port:
其中，i＝1,2,…,N-M+1。Wherein, i=1, 2, . . . , N-M+1.
步骤3：从电压测量模块获取任意K组相邻M+1节液态金属电池端口电压分别为UN-M+2，UN-M+3，…，UN-M+K+1，其中，M-1≤K≤N-M。Step 3: Obtain any K groups of adjacent M+1 liquid metal battery port voltages from the voltage measurement module as U N-M+2 , U N-M+3 ,..., U N-M+K+1 , where , M-1≤K≤NM.
步骤4：根据电压测量的拓扑结构，确定测量端口电压的成分：Step 4: According to the topology of the voltage measurement, determine the composition of the voltage at the measurement port:
其中，l＝N-M+2,N-M+3,…,N-M+K+1。Wherein, l=N-M+2, N-M+3, . . . , N-M+K+1.
步骤5：建立如下电压方程组：Step 5: Establish the following voltage equations:
其中，Ui为第i组第一相邻液态金属电池组的端电压，Ul为第l组第二相邻液态金属电池组的端电压，Xj为第j个液态金属电池的端电压，aij表示第i组第一相邻液态金属电池组的端电压是否包含第j个液态金属电池的端电压，alj表示第l组第二相邻液态金属电池组的端电压是否包含第j个液态金属电池的端电压，1≤j≤N，1≤i≤L，N-M+2≤l≤N-M+K+1。Among them, U i is the terminal voltage of the first adjacent liquid metal battery pack of the i group, U l is the terminal voltage of the second adjacent liquid metal battery pack of the l group, and X j is the terminal voltage of the jth liquid metal battery , a ij indicates whether the terminal voltage of the first adjacent liquid metal battery pack of the i group includes the terminal voltage of the jth liquid metal battery, a lj indicates whether the terminal voltage of the second adjacent liquid metal battery pack of the l group includes the terminal voltage of the jth liquid metal battery pack Terminal voltage of j liquid metal batteries, 1≤j≤N, 1≤i≤L, N-M+2≤l≤N-M+K+1.
步骤6：选取K＝M-1，由电压测量模块获取的端口电压有N个，记为U1，U2，…，UN，并形成电压测量矩阵U＝[U1U2…UN]T；Step 6: Select K=M-1, there are N port voltages obtained by the voltage measurement module, denoted as U 1 , U 2 ,..., U N , and form a voltage measurement matrix U=[U 1 U 2 ...U N ] T ;
由电压测量的拓扑结构形成系数矩阵：Form the coefficient matrix from the topology of the voltage measurement:
N节液态金属电池单体电压X1，X2，…，XN，形成单体电压矩阵X＝[X1X2…XN]T N-section liquid metal battery cell voltage X 1 , X 2 , ..., X N , forming a cell voltage matrix X=[X 1 X 2 ...X N ] T
则电压方程组可以表示为：Then the voltage equations can be expressed as:
U＝AX；U = AX;
步骤7：由电压测量的拓扑结构可知，系数矩阵A是满秩方阵，则X＝A-1U，即可计算出液态金属电池模块串联的各电池单体电压。Step 7: From the topological structure of the voltage measurement, it can be seen that the coefficient matrix A is a full-rank square matrix, then X=A -1 U, and the voltage of each battery cell connected in series with the liquid metal battery module can be calculated.
在本发明提供的液态金属电池电压监测方法的实施例中，令N＝6，M＝3，即由6节液态金属电池单体串联组成液态金属电池模块；对所有相邻的3节液态金属电池引出导线，并测量其端口电压。In the embodiment of the liquid metal battery voltage monitoring method provided by the present invention, let N=6, M=3, that is, the liquid metal battery module is composed of 6 liquid metal battery cells connected in series; for all adjacent 3 liquid metal battery cells Lead out the battery and measure the voltage at its terminals.
如图4所示，引脚0和引脚3测量cell1+cell2+cell3的电压，引脚1和引脚4测量cell2+cell3+cell4的电压，引脚2和引脚5测量cell3+cell4+cell5的电压，引脚3和引脚6测量cell4+cell5+cell6的电压。与此同时，对任意M+1＝4节相邻液态金属电池，测量M-1＝2组端口电压，引脚0和引脚4测量cell1+cell2+cell3+cell4的电压，引脚2和引脚6测量cell3+cell4+cell5+cell6的电压。As shown in Figure 4, pin 0 and pin 3 measure the voltage of cell1+cell2+cell3, pin 1 and pin 4 measure the voltage of cell2+cell3+cell4, pin 2 and pin 5 measure cell3+cell4+ The voltage of cell5, pin 3 and pin 6 measure the voltage of cell4+cell5+cell6. At the same time, for any M+1=4 adjacent liquid metal batteries, measure the port voltage of M-1=2 groups, pin 0 and pin 4 measure the voltage of cell1+cell2+cell3+cell4, pin 2 and Pin 6 measures the voltage of cell3+cell4+cell5+cell6.
电压方程组中，电压测量矩阵、单体电压矩阵以及系数矩阵为：In the voltage equations, the voltage measurement matrix, single voltage matrix and coefficient matrix are:
U＝[U1 U2 U3 U4 U5 U6]T，U=[U 1 U 2 U 3 U 4 U 5 U 6 ] T ,
X＝[X1 X2 X3 X4 X5 X6]T；X=[X 1 X 2 X 3 X 4 X 5 X 6 ] T ;
液态金属电池模块6节串联电池单体电压X＝A-1U，即：The liquid metal battery module has 6 series-connected battery cell voltage X = A -1 U, that is:
本发明提供的液态金属电池电压监测装置，包括电压获取模块和单体电压获取模块，单体电压获取模块输入端与电压获取模块的输出端连接，电压获取模块用于从由N节液态金属电池单体串联形成的电池组单元获取L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压；单体电压获取模块用于根据L组第一相邻液态金属电池组的端电压和K组第二相邻液态金属电池组的端电压获得电压方程组，根据电压方程组获得单个液态金属电池的端电压。The liquid metal battery voltage monitoring device provided by the present invention includes a voltage acquisition module and a single voltage acquisition module. The battery pack unit formed by series connection of cells obtains the terminal voltage of the first adjacent liquid metal battery pack of L group and the terminal voltage of the second adjacent liquid metal battery pack of K group; The terminal voltage of the adjacent liquid metal battery group and the terminal voltage of the K second adjacent liquid metal battery group obtain a voltage equation group, and obtain the terminal voltage of a single liquid metal battery according to the voltage equation group.
电压检测模块是指带有电池电压检测芯片的集成电路，用于检测液态金属电池电压；微处理器模块用于处理电压检测模块获取的电压数据，运算后获得液态金属电池组单体电池电压。由电压检测模块检测上述接入的多节液态金属电池端口电压，并将数据送入微处理器模块进行运算，获得单节液态金属电池电压。The voltage detection module refers to an integrated circuit with a battery voltage detection chip, which is used to detect the voltage of the liquid metal battery; the microprocessor module is used to process the voltage data obtained by the voltage detection module, and obtain the voltage of the single cell of the liquid metal battery pack after calculation. The voltage detection module detects the port voltage of the connected multiple liquid metal batteries, and sends the data to the microprocessor module for calculation to obtain the voltage of the single liquid metal battery.
图5是本发明提供的液态金属电池电压监测方法效果图，通过本发明提供的电池电压监测装置和方法，能有效提高电压监测的精度。Fig. 5 is an effect diagram of the liquid metal battery voltage monitoring method provided by the present invention. The battery voltage monitoring device and method provided by the present invention can effectively improve the accuracy of voltage monitoring.
图6是本发明提供的电池电压监测装置及方法实施电池状态估计的效果对比图，对于低电压、宽平台液态金属电池单体而言，其荷电状态对电压尤其敏感，实施荷电状态估计对电池电压的监测精度要求尤为严格。实际应用中通常采用简单易行的安时积分法进行电池的状态估计，即通过对电流的积分与电池的容量比值计算荷电状态，公式如下：Figure 6 is a comparison diagram of the effect of battery state estimation implemented by the battery voltage monitoring device and method provided by the present invention. For a low-voltage, wide-platform liquid metal battery cell, its state of charge is particularly sensitive to voltage, and state of charge estimation is implemented The monitoring accuracy requirements for the battery voltage are particularly stringent. In practical applications, the simple and easy ampere-hour integration method is usually used to estimate the state of the battery, that is, the state of charge is calculated by the ratio of the integration of the current to the capacity of the battery. The formula is as follows:
其中，Cn为电池容量，i为电流(放电为正值，充电为负值)，SOC0为电池的初始荷电状态。初始荷电状态误差以及电流漂移造成的累计误差均可由开路电压法进行校正。即通过已知的荷电状态-开路电压(SOC-OCV)曲线，由测量得到的电压获取电池的荷电状态。如图6所示，液态金属电池单体电压监测精度的提高，能有效提高荷电状态的校正精度，从而提高电池荷电状态估计的准确度。Among them, C n is the battery capacity, i is the current (discharging is a positive value, charging is a negative value), and SOC 0 is the initial state of charge of the battery. The initial state of charge error and the cumulative error caused by current drift can be corrected by the open circuit voltage method. That is, through the known state of charge-open circuit voltage (SOC-OCV) curve, the state of charge of the battery is obtained from the measured voltage. As shown in Figure 6, the improvement of the monitoring accuracy of the liquid metal battery cell voltage can effectively improve the correction accuracy of the state of charge, thereby improving the accuracy of battery state of charge estimation.
本领域的技术人员容易理解，以上仅为本发明的较佳实施例而已，并不用以先知本发明，凡在本发明的精神和原则之内所作的任何修改、等同替换和改进等，均应包含在本发明的保护范围之内。It is easy for those skilled in the art to understand that the above are only preferred embodiments of the present invention, and are not used to predict the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be Included within the protection scope of the present invention.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711259522.3A CN108091945B (en) | 2017-12-04 | 2017-12-04 | A kind of voltage monitoring method, method for estimating state and the device of liquid metal cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711259522.3A CN108091945B (en) | 2017-12-04 | 2017-12-04 | A kind of voltage monitoring method, method for estimating state and the device of liquid metal cell |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108091945A CN108091945A (en) | 2018-05-29 |
| CN108091945B true CN108091945B (en) | 2019-08-13 |
Family
ID=62172519
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711259522.3A Active CN108091945B (en) | 2017-12-04 | 2017-12-04 | A kind of voltage monitoring method, method for estimating state and the device of liquid metal cell |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108091945B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102195101A (en) * | 2010-03-05 | 2011-09-21 | 陕西铭越信息科技有限公司 | Power battery management system and method thereof |
| CN204303942U (en) * | 2014-12-31 | 2015-04-29 | 中国汽车技术研究中心 | The safety guard of a kind of lithium-ion-power cell voltage monitoring and equilibrium |
| CN105449295A (en) * | 2015-11-17 | 2016-03-30 | 北京新能源汽车股份有限公司 | Power battery balance control method, device and circuit |
| CN205752429U (en) * | 2016-06-27 | 2016-11-30 | 浙江品锐通信科技有限公司 | Intelligent accummulator safeguards system |
-
2017
- 2017-12-04 CN CN201711259522.3A patent/CN108091945B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102195101A (en) * | 2010-03-05 | 2011-09-21 | 陕西铭越信息科技有限公司 | Power battery management system and method thereof |
| CN204303942U (en) * | 2014-12-31 | 2015-04-29 | 中国汽车技术研究中心 | The safety guard of a kind of lithium-ion-power cell voltage monitoring and equilibrium |
| CN105449295A (en) * | 2015-11-17 | 2016-03-30 | 北京新能源汽车股份有限公司 | Power battery balance control method, device and circuit |
| CN205752429U (en) * | 2016-06-27 | 2016-11-30 | 浙江品锐通信科技有限公司 | Intelligent accummulator safeguards system |
Non-Patent Citations (1)
| Title |
|---|
| "液态金属电池储能特性建模及荷电状态估计";王大磊等;《中国电机工程学报》;20170420;第37卷(第8期);全文 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108091945A (en) | 2018-05-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105954679B (en) | A kind of On-line Estimation method of lithium battery charge state | |
| CN103197251B (en) | A kind of discrimination method of dynamic lithium battery Order RC equivalent model | |
| CN110703121A (en) | A method for predicting the state of health of lithium-ion batteries | |
| CN104951662B (en) | A kind of ferric phosphate lithium cell energy state SOE evaluation method | |
| CN108896913A (en) | A kind of evaluation method of health state of lithium ion battery | |
| CN109031145A (en) | A kind of series-parallel battery pack model and implementation method considering inconsistency | |
| CN107748336A (en) | The state-of-charge On-line Estimation method and system of lithium ion battery | |
| US10073145B2 (en) | Method and system for estimating state of charge of battery | |
| CN112526352B (en) | SOH estimation method for retired lithium ion battery | |
| CN102831100A (en) | Method and device for estimating state of charge of battery | |
| CN105319515A (en) | A combined estimation method for the state of charge and the state of health of lithium ion batteries | |
| CN103217651B (en) | A kind of evaluation method of storage battery charge state and system | |
| CN103675698A (en) | Power battery charge state estimating device and method | |
| CN113777501B (en) | SOH estimation method of battery module | |
| CN110794314A (en) | Method for improving lithium ion battery capacity test accuracy | |
| CN104297578B (en) | Ultracapacitor group state-of-charge method of estimation based on sliding mode observer | |
| CN105071546A (en) | Method for correcting remaining power of lithium ion batteries in power system energy storage station | |
| CN107843847A (en) | A kind of battery SOC estimation online methods based on EKF algorithms | |
| CN105866700A (en) | Lithium ion battery quick screening method | |
| CN109004696A (en) | A kind of substation battery multifunction control system and its control method | |
| WO2012062142A1 (en) | Method and apparatus for collecting voltage differential parameters of individual battery cells in battery pack | |
| CN107064809A (en) | The dynamic equivalent circuit model and its method of work of meter and battery electrochemical characteristic | |
| CN110188408A (en) | An operation optimization method for vanadium redox flow battery energy storage system based on particle swarm optimization | |
| CN109752660B (en) | Battery state of charge estimation method without current sensor | |
| CN112858920B (en) | A SOC estimation method for all-vanadium redox flow battery fusion model based on adaptive unscented Kalman filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |