JP2016082749A

JP2016082749A - Storage battery management system, storage battery management device, and storage battery management method

Info

Publication number: JP2016082749A
Application number: JP2014212737A
Authority: JP
Inventors: 久保田　雅之; Masayuki Kubota; 雅之久保田; 正博戸原; Masahiro Tohara; 孝司森本; Koji Morimoto; 小林　武則; Takenori Kobayashi; 武則小林; 智広豊崎; Tomohiro Toyosaki
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2014-10-17
Filing date: 2014-10-17
Publication date: 2016-05-16

Abstract

PROBLEM TO BE SOLVED: To enhance utilization efficiency of a storage battery.SOLUTION: A storage battery management system comprises: first and second storage batteries; a charger/discharger; first and second electric circuits; a charging state detection section; and an electric circuit switching section. The charger/discharger charges/discharges the first and second storage batteries. The first electric circuit connects the first storage battery to the charger/discharger. The second electric circuit connects the first and second storage batteries to the charger/discharger in series. The charging state detection section detects a charging state of the first storage battery charged/discharged by the charger/discharger. The electric circuit switching section switches an electric circuit used to any of the first and second electric circuits on the basis of the charging state of the first storage battery detected by the charging state detection section.SELECTED DRAWING: Figure 1

Description

本発明の実施形態は、蓄電池管理システム、蓄電池管理装置及び蓄電池管理方法に関する。 Embodiments described herein relate generally to a storage battery management system, a storage battery management apparatus, and a storage battery management method.

蓄電池は、例えばインバータを含むパワーコンディショナーなどの充放電装置に接続して利用されることが一般的である。ここで、変換損失などを考慮した充放電装置側の仕様上の制限から、蓄電池は、充放電装置の入力電圧範囲に合わせた電圧範囲で使用される。 The storage battery is generally used by being connected to a charging / discharging device such as a power conditioner including an inverter. Here, the storage battery is used in a voltage range in accordance with the input voltage range of the charging / discharging device because of limitations on the specification on the charging / discharging device side in consideration of conversion loss and the like.

つまり、蓄電池は、実際に動作補償されている補償電圧範囲よりも狭い電圧範囲で使用されるため、利用効率の低下を招いている。なお、蓄電池は、電圧と残容量との関係が一義的に決まっているコンデンサなどとは異なり、残容量の変化の他、劣化状況や蓄電池本体の温度などの変化によっても出力電圧が変化する。このため、蓄電池は、使用可能な電圧範囲に制約を受けている状況では利用効率の向上を図ることが難しくなっている。 That is, since the storage battery is used in a voltage range narrower than the compensation voltage range in which operation compensation is actually performed, the utilization efficiency is reduced. Note that the output voltage of the storage battery changes depending on the deterioration of the remaining capacity, the temperature of the storage battery main body, and the like, in addition to the change of the remaining capacity, unlike a capacitor in which the relationship between the voltage and the remaining capacity is uniquely determined. For this reason, it is difficult for the storage battery to improve the utilization efficiency in a situation where it is restricted by the usable voltage range.

特開２０１３−９５５７号公報JP 2013-9557 A 特開２０１３−５６５６号公報JP 2013-5656 A

本発明が解決しようとする課題は、蓄電池の利用効率を高めることができる蓄電池管理システム、蓄電池管理装置及び蓄電池管理方法を提供することである。 The problem to be solved by the present invention is to provide a storage battery management system, a storage battery management device, and a storage battery management method that can improve the utilization efficiency of the storage battery.

実施の形態の蓄電池管理システムは、第１及び第２の蓄電池、充放電器、第１及び第２の電路、充電状態検出部、並びに電路切替部を備えている。充放電器は、第１及び第２の蓄電池を充放電する。第１の電路は、充放電器に第１の蓄電池を接続する。第２の電路は、充放電器に第１及び第２の蓄電池を直列に接続する。充電状態検出部は、充放電器により充放電される第１の蓄電池の充電状態を検出する。電路切替部は、充電状態検出部により検出された第１の蓄電池の充電状態に基づいて、使用する電路を前記第１及び第２の電路のうちのいずれかに切り替える。 The storage battery management system of the embodiment includes first and second storage batteries, a charger / discharger, first and second electric circuits, a charge state detection unit, and an electric circuit switching unit. The charger / discharger charges and discharges the first and second storage batteries. The first electric circuit connects the first storage battery to the charger / discharger. The second electric circuit connects the first and second storage batteries to the charger / discharger in series. The charge state detection unit detects a charge state of the first storage battery charged / discharged by the charger / discharger. The electric circuit switching unit switches the electric circuit to be used to one of the first and second electric circuits based on the charging state of the first storage battery detected by the charging state detection unit.

第１の実施の形態に係る蓄電池管理システムの構成を概略的に示す図。The figure which shows schematically the structure of the storage battery management system which concerns on 1st Embodiment. 図１の蓄電池管理システムが備える第１の蓄電池の充電状態と出力電圧との関係を示す図。The figure which shows the relationship between the charge condition of the 1st storage battery with which the storage battery management system of FIG. 1 is provided, and an output voltage. 第１の蓄電池の充電状態と第１、第２の蓄電池の出力電圧との関係を示す図。The figure which shows the relationship between the charge condition of a 1st storage battery, and the output voltage of a 1st, 2nd storage battery. 図１の蓄電池管理システムによる蓄電池管理方法を示すフローチャート。The flowchart which shows the storage battery management method by the storage battery management system of FIG. 第２の実施の形態に係る蓄電池管理システムの構成を概略的に示す図。The figure which shows schematically the structure of the storage battery management system which concerns on 2nd Embodiment. 第３の実施の形態に係る蓄電池管理システムの構成を概略的に示す図。The figure which shows schematically the structure of the storage battery management system which concerns on 3rd Embodiment. 図６の蓄電池管理システムによる蓄電池管理方法を示すフローチャート。The flowchart which shows the storage battery management method by the storage battery management system of FIG.

以下、実施の形態を図面に基づき説明する。
＜第１の実施の形態＞
図１に示すように、本実施形態の蓄電池管理システム１０は、第１の蓄電池１、第２の蓄電池２、充放電器６、及び蓄電池管理装置１０ａを備えている。蓄電池管理装置１０ａは、第１の電路２１、第２の電路２２、第１〜第３の開閉器１１〜１３、並びに、充電状態検出部（第１の充電状態検出部）８ａ及び開閉器制御部８ｂを含む制御装置８を有している。 Hereinafter, embodiments will be described with reference to the drawings.
<First Embodiment>
As shown in FIG. 1, the storage battery management system 10 of this embodiment is provided with the 1st storage battery 1, the 2nd storage battery 2, the charger / discharger 6, and the storage battery management apparatus 10a. The storage battery management device 10a includes a first electric circuit 21, a second electric circuit 22, first to third switches 11 to 13, a charging state detection unit (first charging state detection unit) 8a, and switch control. It has the control apparatus 8 containing the part 8b.

蓄電池管理装置１０ａは、電路切替部（第１の電路切替部）３１をさらに備えている。電路切替部３１は、第１及び第２の開閉器１１、１２（及び第３の開閉器１３）と制御装置８の開閉器制御部８ｂとが、互いに協働して動作することによって実現される。第１及び第２の蓄電池１、２は、リチウムイオン電池などの二次電池である。また、第１及び第２の蓄電池１、２のそれぞれは、直列及び／又は並列に接続された複数のバッテリセル（電池セル）を備えたバッテリパック（組電池）である。 The storage battery management device 10 a further includes an electric circuit switching unit (first electric circuit switching unit) 31. The electric circuit switching unit 31 is realized by the first and second switches 11 and 12 (and the third switch 13) and the switch control unit 8b of the control device 8 operating in cooperation with each other. The The 1st and 2nd storage batteries 1 and 2 are secondary batteries, such as a lithium ion battery. In addition, each of the first and second storage batteries 1 and 2 is a battery pack (assembled battery) including a plurality of battery cells (battery cells) connected in series and / or in parallel.

第１の蓄電池１は、使用中の安全性などが考慮され、動作補償している補償電圧範囲が例えば１．５Ｖ〜３Ｖのバッテリセルを、例えば１００個、直列に接続して構成されている。第２の蓄電池２は、第１の蓄電池１よりも、例えば定格の出力電圧が低くなるように構成されている。 The first storage battery 1 is configured by connecting in series, for example, 100 battery cells having a compensation voltage range of 1.5 V to 3 V, for example, in consideration of safety during use, and the like. . The 2nd storage battery 2 is comprised so that a rated output voltage may become lower than the 1st storage battery 1, for example.

充放電器６は、第１及び第２の蓄電池１、２を充放電することが可能である。充放電器６は、例えばインバータを含むパワーコンディショナー（ＰＣＳ：Power Conditioning System）などである。また、充放電器６は、（その一方に）図示しない例えば電力系統や例えば交流の電力を給電されて動作する電子機器などが接続されている。 The charger / discharger 6 can charge and discharge the first and second storage batteries 1 and 2. The charger / discharger 6 is, for example, a power conditioner (PCS) including an inverter. In addition, the charger / discharger 6 is connected to (on one side), for example, an electric power system (not shown) or an electronic device that operates by being supplied with AC power.

このような充放電器６は、半導体スイッチを内部に備えており、スイッチングのタイミングを変化させることによって、出力する電力や電流を変化させる。ここで、充放電器６は、変換損失などを考慮し、入力電圧Ｖ_nが、２００Ｖ〜３００Ｖの入力電圧範囲に制限された仕様となっている。 Such a charger / discharger 6 includes a semiconductor switch therein, and changes output power and current by changing the switching timing. Here, the charger / discharger 6 has a specification in which the input voltage V _n is limited to an input voltage range of 200V to 300V in consideration of conversion loss and the like.

第１〜第３の開閉器１１〜１３は、コンダクタや半導体などを用いたスイッチング素子によって構成されている。第１の電路２１は、充放電器６（の他方）に、第１、第３の開閉器１１、１３を介して第１の蓄電池１を単独で接続する。具体的には、第１の電路２１は、第１の蓄電池１の正極から、第３の開閉器１３、充放電器６、第１の開閉器１１、第１の蓄電池１の負極へ、とつながる電路である。 The 1st-3rd switches 11-13 are comprised by the switching element using a conductor, a semiconductor, etc. The first electric circuit 21 connects the first storage battery 1 alone to the charger / discharger 6 (the other) via the first and third switches 11 and 13. Specifically, the first electric circuit 21 extends from the positive electrode of the first storage battery 1 to the third switch 13, the charger / discharger 6, the first switch 11, and the negative electrode of the first storage battery 1. It is a connecting electric circuit.

一方、第２の電路２２は、充放電器６（の他方）に、第２、第３の開閉器１２、１３を介して第１及び第２の蓄電池１、２を直列に接続（正接続）する。詳述すると、第２の電路２２は、第１の蓄電池１の正極から、第３の開閉器１３、充放電器６、第２の蓄電池２、第２の開閉器１２、第１の蓄電池１の負極へ、とつながる電路である。 On the other hand, the second electric circuit 22 connects the first and second storage batteries 1 and 2 in series to the charger / discharger 6 (the other) via the second and third switches 12 and 13 (positive connection). ) Specifically, the second electric circuit 22 is connected to the third switch 13, the charger / discharger 6, the second storage battery 2, the second switch 12, and the first storage battery 1 from the positive electrode of the first storage battery 1. It is an electric circuit that leads to the negative electrode.

制御装置８は、第１及び第２の蓄電池１、２に対する充放電を行うための指令を、充放電器６に与える。制御装置８が備える充電状態検出部８ａは、充放電器６により充放電される少なくとも第１の蓄電池１の充電状態（ＳＯＣ：State of Charge）を検出する。充電状態検出部８ａは、第１の蓄電池１の電圧、温度、通電時の電流値などを計測した結果に基づき、充電状態を演算によって求める。制御装置８が備える開閉器制御部８ｂは、第１〜第３の開閉器１１〜１３を個別に開閉（ＯＮ／ＯＦＦ）する。 The control device 8 gives a command for charging / discharging the first and second storage batteries 1, 2 to the charger / discharger 6. The charging state detection unit 8 a included in the control device 8 detects a charging state (SOC: State of Charge) of at least the first storage battery 1 charged / discharged by the charger / discharger 6. The charging state detection unit 8a obtains the charging state by calculation based on the results of measuring the voltage, temperature, current value during energization of the first storage battery 1, and the like. The switch control unit 8b included in the control device 8 individually opens and closes (ON / OFF) the first to third switches 11 to 13.

また、上述した電路切替部３１は、充電状態検出部８ａにより検出された第１の蓄電池１の充電状態に基づいて、使用する電路を、第１及び第２の電路２１、２２のうちのいずれかに切り替える。具体的には、使用する電路を第１の電路２１に切り替える場合（第１の電路２１を選択する場合）、電路切替部３１は、開閉器制御部８ｂを介して、第１、第３の開閉器１１、１３をＯＮにする（閉じる）と共に、第２の開閉器１２をＯＦＦにする（開放する）。 In addition, the above-described electric circuit switching unit 31 determines which electric circuit to use based on the state of charge of the first storage battery 1 detected by the state of charge detection unit 8a. Switch to Specifically, when the electric circuit to be used is switched to the first electric circuit 21 (when the first electric circuit 21 is selected), the electric circuit switching unit 31 uses the first and third switches via the switch control unit 8b. The switches 11 and 13 are turned on (closed), and the second switch 12 is turned off (opened).

一方、使用する電路を第２の電路２２に切り替える場合（第２の電路２２を選択する場合）、電路切替部３１は、開閉器制御部８ｂを介して、第１の開閉器１１をＯＦＦにすると共に、第２、第３の開閉器１２、１３をＯＮにする。 On the other hand, when the electric circuit to be used is switched to the second electric circuit 22 (when the second electric circuit 22 is selected), the electric circuit switching unit 31 turns off the first switch 11 via the switch control unit 8b. At the same time, the second and third switches 12 and 13 are turned ON.

ここで、図２は、第１の蓄電池１の充電状態と出力電圧との関係を示している。図２中において、Ｒ_mは、充放電器６の動作可能電圧範囲（入力電圧範囲）であり、Ｒ_uは、上記動作可能電圧範囲の制限を受けて、第１の蓄電池１の電池容量を使用できる使用可能ＳＯＣ範囲である。また、Ｖ_cは、充電電流を流しているときの第１の蓄電池１の出力電圧であり、Ｖ_dは、放電電流を流しているときの第１の蓄電池１の出力電圧であり、さらに、Ｖ_sは、充放電を停止しているときの第１の蓄電池１の出力電圧である。 Here, FIG. 2 shows the relationship between the state of charge of the first storage battery 1 and the output voltage. In FIG. 2, R _m is operable voltage range of the charge and discharge device 6 (input voltage range), R _u is restricted the operable voltage range, the first battery capacity of the storage battery 1 The usable SOC range that can be used. Further, V _c is an output voltage of the first storage battery 1 when a charging current is flowing, V _d is an output voltage of the first storage battery 1 when a discharging current is flowing, V _s is the output voltage of the first storage battery 1 when charging / discharging is stopped.

一方、図３は、第１の蓄電池１の充電状態と、第１の蓄電池１の出力電圧並びに第１及び第２の蓄電池１、２を直列に接続したときの出力電圧と、の関係を示している。図３中のＲ_eは、充放電器６に第１の蓄電池１を単独で接続しているとき（使用する電路を第１の電路２１に切り替えたとき）の特性範囲であり、Ｒ_fは、第１及び第２の蓄電池１、２が充放電器６に直列に接続されているとき（使用する電路を第２の電路２２に切り替えたとき）の特性範囲である。 On the other hand, FIG. 3 shows the relationship between the state of charge of the first storage battery 1, the output voltage of the first storage battery 1, and the output voltage when the first and second storage batteries 1 and 2 are connected in series. ing. R _e in FIG. 3 is a characteristic range when (when switching path to be used for the first path 21) that connects the first battery 1 charging and discharging device 6 alone, R _f is This is a characteristic range when the first and second storage batteries 1, 2 are connected to the charger / discharger 6 in series (when the electric circuit to be used is switched to the second electric circuit 22).

また、Ｖ_c1は、直列に接続した第１及び第２の蓄電池１、２に充電電流を流しているときの出力電圧であり、Ｖ_d1は、直列に接続した第１及び第２の蓄電池１、２に放電電流を流しているときの出力電圧であり、さらに、Ｖ_s1は、直列に接続した第１及び第２の蓄電池１、２に対して充放電を停止しているときの出力電圧である。 V _c1 is an output voltage when charging current is passed through the first and second storage batteries 1 and 2 connected in series, and V _d1 is the first and second storage batteries 1 connected in series. 2 is an output voltage when a discharge current is flowing, and V _s1 is an output voltage when charging and discharging are stopped for the first and second storage batteries 1 and 2 connected in series. It is.

ここで、制御装置８は、図２、図３に示す第１の蓄電池１の充電状態と出力電圧との関係を、例えばテーブルの形式で記憶している。さらに、制御装置８は、第１の充電状態閾値ＳＯＣ_th1（例えば３０％）と第２の充電状態閾値ＳＯＣ_th2（例えば３５％）とを記憶している。電路切替部３１は、第１の蓄電池１の充電状態（ＳＯＣ）が、第１の充電状態閾値ＳＯＣ_th1以下に減少したタイミングで、使用する電路を第２の電路２２に切り替える（第１及び第２の蓄電池１、２の直列接続を選択する）。また、電路切替部３１は、第１の蓄電池１の充電状態が、第２の充電状態閾値ＳＯＣ_th2以上に上昇したタイミングで、使用する電路を第１の電路２１に切り替える（第１の蓄電池１の単独の接続を選択する）。 Here, the control apparatus 8 has memorize | stored the relationship between the charge condition of the 1st storage battery 1 shown in FIG. 2, FIG. 3, and an output voltage in the form of a table, for example. Further, the control device 8 stores a first charge state threshold SOC _th1 (for example, 30%) and a second charge state threshold SOC _th2 (for example, 35%). The electric circuit switching unit 31 switches the electric circuit to be used to the second electric circuit 22 at the timing when the state of charge (SOC) of the first storage battery 1 decreases to the first state of charge threshold SOC _th1 or less (first and first electric circuits). 2 in series connection of storage batteries 1 and 2). Moreover, the electric circuit switching part 31 switches the electric circuit to be used to the 1st electric circuit 21 at the timing when the charge condition of the 1st storage battery 1 rose more than 2nd charge condition threshold value SOC _th2 (1st storage battery 1 Select a single connection).

詳述すると、図２及び図３では、充放電器６の動作可能電圧範囲（入力電圧範囲）Ｒ_mにおける下限値の２００Ｖに対応する蓄電池の残容量を例えば３０％として仮定している。つまり、第１の蓄電池１の充電状態が０％〜３０％の範囲では、第１の蓄電池１単独での放電はできないことになる。 Specifically, in FIGS. 2 and 3, it is assumed that the remaining capacity of the storage battery corresponding to the lower limit value 200 V in the operable voltage range (input voltage range) R _m of the charger / discharger 6 is, for example, 30%. That is, when the state of charge of the first storage battery 1 is in the range of 0% to 30%, the first storage battery 1 alone cannot be discharged.

図３では、第１の蓄電池１の充電状態が第１の充電状態閾値ＳＯＣ_th1（３０％）に減少したタイミングで充電状態が例えば１００％の第２の蓄電池２を、第１の蓄電池１に直列に接続した場合の特性範囲Ｒ_fを例示している。ここで、第１の蓄電池１内のバッテリセルと第２の蓄電池２内のバッテリセルとがほぼ同時に１．５Ｖに到達するように、第１の蓄電池１と第２の蓄電池２とのそれぞれにおいて、バッテリセルの直列方向及び並列方向における各配列数を互いに一致させることで、蓄電池の利用効率を向上させる効果が得られる。 In FIG. 3, the second storage battery 2 whose charge state is 100%, for example, is changed to the first storage battery 1 at the timing when the charge state of the first storage battery 1 is reduced to the first charge state threshold SOC _th1 (30%). The characteristic range R _f when connected in series is illustrated. Here, in each of the 1st storage battery 1 and the 2nd storage battery 2 so that the battery cell in the 1st storage battery 1 and the battery cell in the 2nd storage battery 2 reach 1.5V almost simultaneously. The effect of improving the use efficiency of the storage battery can be obtained by matching the numbers of the battery cells in the series direction and the parallel direction.

本実施形態では、第１及び第２の蓄電池１、２を直列接続に切り替えるための第１の充電状態閾値ＳＯＣ_th1を３０％として例示したが、充放電器６の最大効率点を考慮して第１の充電状態閾値ＳＯＣ_th1を設定することが蓄電池の利用における高効率化につながる。このため、図３に示すように、直列に接続した第１及び第２の蓄電池１、２に充電電流を流しているときの出力電圧Ｖ_c1の最大値が、充放電器６の動作可能電圧範囲Ｒ_mの上限付近にくるように、第１の充電状態閾値ＳＯＣ_th1を設定することが望ましい。 In the present embodiment, the first charge state threshold SOC _th1 for switching the first and second storage batteries 1 and 2 to series connection is exemplified as 30%, but the maximum efficiency point of the charger / discharger 6 is taken into consideration. Setting the first state-of-charge threshold SOC _th1 leads to higher efficiency in the use of the storage battery. For this reason, as shown in FIG. 3, the maximum value of the output voltage V _c1 when the charging current is passed through the first and second storage batteries 1 and 2 connected in series is the operable voltage of the charger / discharger 6. It is desirable to set the first state-of-charge threshold SOC _th1 so as to be near the upper limit of the range R _m .

次に、本実施形態の蓄電池管理システム１０による蓄電池管理方法を図４に示すフローチャートに基づいて説明する。制御装置８の充電状態検出部８ａは、充放電器６により充放電される第１の蓄電池１の充電状態を検出する。図４に示すように、充電状態検出部８ａにより検出された第１の蓄電池１の充電状態（ＳＯＣ）が、第１の充電状態閾値ＳＯＣ_th1（例えば３０％）以下に減少した場合（Ｓ１のＹＥＳ）、電路切替部３１は、このタイミングで、開閉器制御部８ｂを介して、第１の開閉器１１をＯＦＦにすると共に、第２の開閉器１２（及び第３の開閉器１３）をＯＮにして（Ｓ２）、使用する電路を第２の電路２２に切り替える（充放電器６に第１及び第２の蓄電池１、２を直列に接続する）。 Next, the storage battery management method by the storage battery management system 10 of this embodiment is demonstrated based on the flowchart shown in FIG. The charging state detection unit 8 a of the control device 8 detects the charging state of the first storage battery 1 that is charged and discharged by the charger / discharger 6. As shown in FIG. 4, when the state of charge (SOC) of the first storage battery 1 detected by the state of charge detection unit 8a decreases to a first charge state threshold SOC _th1 (for example, 30%) or less (in S1) YES), the electric circuit switching unit 31 turns off the first switch 11 and the second switch 12 (and the third switch 13) via the switch control unit 8b at this timing. It turns ON (S2), and switches the electric circuit to be used to the second electric circuit 22 (the first and second storage batteries 1, 2 are connected in series to the charger / discharger 6).

さらに、充電状態検出部８ａにより検出された第１の蓄電池１の充電状態（ＳＯＣ）が、第２の充電状態閾値ＳＯＣ_th2（例えば３５％）以上に上昇した場合（Ｓ３のＹＥＳ）、電路切替部３１は、このタイミングで、開閉器制御部８ｂを介して、第２の開閉器１２をＯＦＦにすると共に、第１の開閉器１１（及び第３の開閉器１３）をＯＮにして（Ｓ４）、使用する電路を第１の電路２１に切り替える（充放電器６に第１の蓄電池１を単独で接続する）。 Further, when the state of charge (SOC) of the first storage battery 1 detected by the state of charge detection unit 8a has risen to the second state of charge threshold SOC _th2 (for example, 35%) or more (YES in S3), the circuit is switched. At this timing, the unit 31 turns off the second switch 12 and turns on the first switch 11 (and the third switch 13) via the switch control unit 8b (S4). ), The electric circuit to be used is switched to the first electric circuit 21 (the first storage battery 1 is connected to the charger / discharger 6 alone).

既述したように、本実施形態の蓄電池管理システム１０によれば、図３に示すように、第１の蓄電池１の充電状態（ＳＯＣ）が例えば３０％以下の範囲（第１の蓄電池１の出力電圧が、充放電器６の動作可能電圧範囲以下）であっても、第２の蓄電池２を第１の蓄電池１と共に活用することで、実質的に第１の蓄電池１の利用効率を高めることができる。 As described above, according to the storage battery management system 10 of the present embodiment, as shown in FIG. 3, the state of charge (SOC) of the first storage battery 1 is, for example, 30% or less (of the first storage battery 1). Even if the output voltage is equal to or less than the operable voltage range of the charger / discharger 6, the utilization efficiency of the first storage battery 1 is substantially increased by utilizing the second storage battery 2 together with the first storage battery 1. be able to.

なお、充放電器６による充放電中に第１〜第３の開閉器１１〜１３が開閉動作することを回避するために、充放電器６が充放電を停止している待機期間に、これらの開閉器を開閉動作させるように電路切替部３１を構成してもよい。これにより、充放電中の開閉器の開閉動作によって、充放電が中断されることを阻止できる。また、第２の蓄電池２には、例えば第１の蓄電池１の電圧を監視する監視制御用の電源や、開閉器駆動用の電源などとして使用されている蓄電池を流用することも可能である。 In addition, in order to avoid that the 1st-3rd switch 11-13 opens and closes during charging / discharging by the charger / discharger 6, in the waiting period when the charger / discharger 6 has stopped charging / discharging, The electric circuit switching unit 31 may be configured to open and close the switch. Thereby, it can prevent that charging / discharging is interrupted by the opening / closing operation | movement of the switch during charging / discharging. In addition, for example, a storage battery used as a power source for monitoring control for monitoring the voltage of the first storage battery 1 or a power source for driving a switch can be used as the second storage battery 2.

＜第２の実施の形態＞
次に、第２の実施形態を図５に基づき説明する。なお、図５中において、図１に示した第１の実施形態中の構成要素と同一の構成要素については、同一の符号を付与しその説明を省略する。 <Second Embodiment>
Next, a second embodiment will be described based on FIG. In FIG. 5, the same components as those in the first embodiment shown in FIG.

第２の実施形態の蓄電池管理システム２０は、図５に示すように、第１の実施形態の蓄電池管理システム１０が備えていた第１の蓄電池１に代えて、第１の蓄電池４１を備えている。第１の蓄電池４１は、直列及び／又は並列に接続された複数のバッテリセルを備えている。この第１の蓄電池４１と第２の蓄電池２とは、バッテリセルの直列方向の配列数とバッテリセルの並列方向の配列数とのうちの、少なくとも一方が異なっている。また、相対的に、第２の蓄電池２は、自身が備えているバッテリセルの総数を、上記した第１の蓄電池４１よりも少なくして構成されていることになる。 As shown in FIG. 5, the storage battery management system 20 of the second embodiment includes a first storage battery 41 instead of the first storage battery 1 included in the storage battery management system 10 of the first embodiment. Yes. The first storage battery 41 includes a plurality of battery cells connected in series and / or in parallel. The first storage battery 41 and the second storage battery 2 are different in at least one of the number of battery cells arranged in the series direction and the number of battery cells arranged in the parallel direction. In comparison, the second storage battery 2 is configured such that the total number of battery cells included in the second storage battery 2 is smaller than that of the first storage battery 41 described above.

ここで、第２の蓄電池２内におけるバッテリセルの並列方向の配列数が、第１の蓄電池４１内におけるバッテリセルの並列方向の配列数よりも、少なくなっている構成の場合、第２の蓄電池２内におけるバッテリセルには、第１の蓄電池４１内のバッテリセルと比較してより多くの電流が流れることになる。なお、リチウムイオン電池に代表される蓄電池は、一般に、大電流が流れることや充放電時の発熱によって、バッテリセルの温度が高くなっている状態が継続されると傾向的に劣化しやすくなる。さらに大規模な蓄電池の場合、電池交換を行う際には、例えば電池盤内のユニットをすべて交換するか、又は電池盤全体を交換することになり、いずれにしても大きな時間的コストの損失が発生する。この点を踏まえると、上記したように、バッテリセルに多くの電流が流れる第２の蓄電池２は、劣化しやすい構成ではあるものの、第１の蓄電池４１と比較して、バッテリセルの総数が少なく、交換作業などが容易となり、実質的にメンテナンス性を高めることが可能となる。 Here, in the case of a configuration in which the number of battery cells arranged in the second storage battery 2 in the parallel direction is smaller than the number of battery cells arranged in the first storage battery 41 in the parallel direction, the second storage battery The battery cell in 2 will flow more current than the battery cell in the first storage battery 41. Note that a storage battery represented by a lithium ion battery generally tends to deteriorate when a state in which the temperature of the battery cell is high is continued due to a large current flowing or heat generated during charging and discharging. In the case of a large-scale storage battery, when replacing the battery, for example, all the units in the battery panel are replaced or the entire battery panel is replaced. Occur. In consideration of this point, as described above, the second storage battery 2 in which a large amount of current flows in the battery cell is easily deteriorated, but the total number of battery cells is smaller than that of the first storage battery 41. Thus, replacement work and the like are facilitated, and maintenance can be substantially improved.

また、一般に、蓄電池は、劣化の抑制のためには温度の低い環境で使用することが好ましいが、高温になりやすい環境に第１及び第２の蓄電池４１、２のいずれかを設置する必要がある場合には、蓄電池管理システム２０では、交換作業の容易な第２の蓄電池２を高温になりやすい環境に優先的に配置することなどが提案される。具体的には、例えば電池盤として構成された第２の蓄電池２を建屋内に独立して設置する場合、比較的高温になることを回避できない場所（例えば、日当たりのよい場所、発熱体の近く、建屋内の熱がこもりやすい天井付近など）に、上記したように、交換作業の容易な当該第２の蓄電池２を設置することが望ましい。 In general, the storage battery is preferably used in a low temperature environment in order to suppress deterioration. However, it is necessary to install either the first or second storage battery 41 or 2 in an environment where the temperature tends to be high. In some cases, the storage battery management system 20 proposes to preferentially arrange the second storage battery 2 that can be easily replaced in an environment that is likely to be hot. Specifically, for example, when the second storage battery 2 configured as a battery panel is installed independently in a building, a place where a relatively high temperature cannot be avoided (for example, a sunny place, near a heating element) As described above, it is desirable to install the second storage battery 2 that can be easily replaced as described above in the vicinity of the ceiling where the heat in the building is likely to be trapped.

＜第３の実施の形態＞
次に、第３の実施形態を図６、図７に基づき説明する。なお、図６中において、図１に示した第１の実施形態中の構成要素と同一の構成要素については、同一の符号を付与しその説明を省略する。 <Third Embodiment>
Next, a third embodiment will be described with reference to FIGS. In FIG. 6, the same constituent elements as those in the first embodiment shown in FIG.

図６に示すように、第３の実施形態に係る蓄電池管理システム３０は、第１の実施形態に係る蓄電池管理システム１０が有する蓄電池管理装置１０ａに代えて、蓄電池管理装置３０ａを備えている。蓄電池管理装置３０ａは、蓄電池管理装置１０ａの制御装置８に代えて、充電状態検出部（第２の充電状態検出部）３８ａ及び開閉器制御部３８ｂを含む制御装置３８を有すると共に、第３の電路２３及び第４、第５の開閉器１４、１５をさらに備えている。 As shown in FIG. 6, the storage battery management system 30 according to the third embodiment includes a storage battery management device 30a instead of the storage battery management device 10a included in the storage battery management system 10 according to the first embodiment. The storage battery management device 30a has a control device 38 including a charge state detection unit (second charge state detection unit) 38a and a switch control unit 38b instead of the control device 8 of the storage battery management device 10a. An electric circuit 23 and fourth and fifth switches 14 and 15 are further provided.

蓄電池管理装置３０ａは、電路切替部（第２の電路切替部）３２をさらに備えている。第２の電路切替部３２は、第１〜第５の開閉器１１〜１５と制御装置３８の開閉器制御部３８ｂとが、互いに協働して動作することによって実現される。 The storage battery management device 30 a further includes an electric circuit switching unit (second electric circuit switching unit) 32. The second electric circuit switching unit 32 is realized by the first to fifth switches 11 to 15 and the switch control unit 38b of the control device 38 operating in cooperation with each other.

第４、第５の開閉器１４、１５も、コンダクタや半導体などを用いたスイッチング素子によって構成されている。図６に示すように、第３の電路２３は、充放電器６（の他方）に、第３〜第５の開閉器１３〜１５を介して、第１及び第２の蓄電池１、２を直列に接続すると共に第１の蓄電池１に対して第２の蓄電池２を逆接続の関係で接続する（逆接続する）。具体的には、第３の電路２３は、第１の蓄電池１の正極から、第３の開閉器１３、充放電器６、第４の開閉器１４、第２の蓄電池２の正極、第２の蓄電池２の負極、第５の開閉器１５、第１の蓄電池１の負極へ、とつながる電路である。 The fourth and fifth switches 14 and 15 are also constituted by switching elements using conductors or semiconductors. As shown in FIG. 6, the third electric circuit 23 connects the first and second storage batteries 1 and 2 to the charger / discharger 6 (the other) via the third to fifth switches 13 to 15. In addition to being connected in series, the second storage battery 2 is connected to the first storage battery 1 in a reverse connection relationship (reverse connection). Specifically, the third electric circuit 23 starts from the positive electrode of the first storage battery 1, the third switch 13, the charger / discharger 6, the fourth switch 14, the positive electrode of the second storage battery 2, the second It is an electric circuit connected to the negative electrode of the storage battery 2, the fifth switch 15, and the negative electrode of the first storage battery 1.

制御装置３８が備える充電状態検出部（第２の充電状態検出部）３８ａは、充放電器６により充放電される第１及び第２の蓄電池それぞれの充電状態を検出する。制御装置８が備える開閉器制御部８ｂは、第１〜第５の開閉器１１〜１５を個別に開閉（ＯＮ／ＯＦＦ）する。 The charging state detection unit (second charging state detection unit) 38 a included in the control device 38 detects the charging states of the first and second storage batteries that are charged and discharged by the charger / discharger 6. The switch control part 8b with which the control apparatus 8 is provided opens and closes (ON / OFF) the 1st-5th switch 11-15 separately.

また、上述した第２の電路切替部３２は、充電状態検出部３８ａにより検出された第１及び第２の蓄電池１、２それぞれの充電状態（ＳＯＣ）に基づいて、使用する電路を第１〜第３の電路２１〜２３のうちのいずれかに切り替える。具体的には、使用する電路を第３の電路２３に切り替える場合（第３の電路２３を選択する場合）、第２の電路切替部３２は、開閉器制御部３８ｂを介して、第３〜第５の開閉器１３〜１５をＯＮにする（閉じる）と共に、第１、第２の開閉器１１、１２をＯＦＦにする（開放する）。 In addition, the second electric circuit switching unit 32 described above selects the electric circuit to be used based on the charge states (SOC) of the first and second storage batteries 1 and 2 detected by the charge state detection unit 38a. Switch to any of the third electrical paths 21-23. Specifically, when the electric circuit to be used is switched to the third electric circuit 23 (when the third electric circuit 23 is selected), the second electric circuit switching unit 32 is connected to the third to third circuits via the switch control unit 38b. The fifth switches 13 to 15 are turned on (closed), and the first and second switches 11 and 12 are turned off (opened).

さらに、使用する電路を第１の電路２１に切り替える場合、第２の電路切替部３２は、開閉器制御部３８ｂを介して、第１、第３の開閉器１１、１３をＯＮにすると共に、第２、第４、第５の開閉器１２、１４、１５をＯＦＦにする。また、使用する電路を第２の電路２２に切り替える場合、第２の電路切替部３２は、開閉器制御部３８ｂを介して、第２、第３の開閉器１２、１３をＯＮにすると共に、第１、第４、第５の開閉器１１、１４、１５をＯＦＦにする。 Furthermore, when switching the electric circuit to be used to the first electric circuit 21, the second electric circuit switching unit 32 turns on the first and third switches 11, 13 via the switch control unit 38b, The second, fourth, and fifth switches 12, 14, and 15 are turned off. In addition, when the electric circuit to be used is switched to the second electric circuit 22, the second electric circuit switching unit 32 turns on the second and third switches 12 and 13 via the switch control unit 38b, The first, fourth, and fifth switches 11, 14, and 15 are turned off.

また、制御装置３８は、第１の充電状態閾値ＳＯＣ_th1（本実施形態では例えば８０％）と、第２の充電状態閾値ＳＯＣ_th2（本実施形態では例えば８０％）と、第３の充電状態閾値ＳＯＣ_th3（例えば１００％）と、第４の充電状態閾値ＳＯＣ_th4（例えば１００％）と、を記憶している。 Further, the control device 38 includes a first charge state threshold SOC _th1 (for example, 80% in the present embodiment), a second charge state threshold SOC _th2 (for example, 80% in the present embodiment), and a third charge state. A threshold SOC _th3 (for example, 100%) and a fourth charge state threshold SOC _th4 (for example, 100%) are stored.

ここで、例えば、第１の蓄電池１の充電状態が３０％〜１００％の範囲内にある場合、第１の蓄電池１の充電状態が第１の充電状態閾値（３０％）以下に減少してしまうことに備え、図３中に例示した特性（図３中の特性範囲Ｒ_f内の特性）が得られるように、第２の蓄電池２の充電状態が、１００％に保たれていることが理想的である。しかしながら、蓄電池は、自己放電などによる影響で充電状態が低下する場合がある。 Here, for example, when the state of charge of the first storage battery 1 is in the range of 30% to 100%, the state of charge of the first storage battery 1 is reduced below the first state of charge threshold (30%). In preparation for this, the state of charge of the second storage battery 2 may be maintained at 100% so that the characteristics illustrated in FIG. 3 (characteristics within the characteristic range _Rf in FIG. 3) can be obtained. Ideal. However, the state of charge of the storage battery may decrease due to the influence of self-discharge or the like.

例えば、第１の蓄電池１の充電状態が比較的高くない場合（例えば８０％以下の場合）、第１及び第２の蓄電池１、２を直列に接続して、充放電器６から充電すれば、第２の蓄電池２の充電状態が上昇し、充電状態を１００％付近に近付けることが可能である。これに対して、第１の蓄電池１の充電状態が高い場合（例えば８０％以上の場合）、第１及び第２の蓄電池１、２を直列に接続して、充放電器６から充電すると、蓄電池全体の出力電圧が上昇して、充放電器の動作可能電圧範囲を逸脱する可能性があり、第２の蓄電池２の充電状態を１００％に近付けることが困難となる。 For example, when the charge state of the first storage battery 1 is not relatively high (for example, 80% or less), the first and second storage batteries 1 and 2 are connected in series and charged from the charger / discharger 6. The state of charge of the second storage battery 2 is increased, and the state of charge can be brought close to 100%. On the other hand, when the charging state of the first storage battery 1 is high (for example, 80% or more), the first and second storage batteries 1, 2 are connected in series and charged from the charger / discharger 6, The output voltage of the entire storage battery may rise and deviate from the operable voltage range of the charger / discharger, making it difficult to bring the charge state of the second storage battery 2 close to 100%.

このような状況において、蓄電池管理システム３０が備える第２の電路切替部３２は、図６に示すように、開閉器制御部３８ｂを介して、第３〜第５の開閉器１３〜１５をＯＮにすると共に、第１、第２の開閉器１１、１２をＯＦＦにして、使用する電路を第３の電路２３に切り替える。ここで、第３の電路２３は、充放電器６に、第１及び第２の蓄電池１、２を直列に接続すると共に第１の蓄電池１に対して第２の蓄電池２を逆接続する。これにより、第１の蓄電池１は放電し、一方、第２の蓄電池２は充電されることになるため、第２の蓄電池２の充電状態を１００％に近付けることが可能となる。 In such a situation, the second electric circuit switching unit 32 provided in the storage battery management system 30 turns on the third to fifth switches 13 to 15 via the switch control unit 38b as shown in FIG. In addition, the first and second switches 11 and 12 are turned OFF, and the electric circuit to be used is switched to the third electric circuit 23. Here, the third electric circuit 23 connects the first and second storage batteries 1 and 2 in series to the charger / discharger 6 and reversely connects the second storage battery 2 to the first storage battery 1. As a result, the first storage battery 1 is discharged, while the second storage battery 2 is charged, so that the charged state of the second storage battery 2 can be brought close to 100%.

次に、本実施形態の蓄電池管理システム３０による蓄電池管理方法を図７に示すフローチャートに基づき説明する。制御装置３８の充電状態検出部３８ａは、充放電器６により充放電される第１及び第２の蓄電池１、２それぞれの充電状態（ＳＯＣ）を検出する。図７に示すように、検出された第２の蓄電池２の充電状態が、第１の充電状態閾値ＳＯＣ_th1（例えば８０％）以下に減少しおり（Ｓ１１のＹＥＳ）、さらに、第１の蓄電池１の充電状態が、第２の充電状態閾値ＳＯＣ_th2（例えば８０％）と第３の充電状態閾値ＳＯＣ_th3（例えば１００％）との間にある場合（Ｓ１２のＹＥＳ）、第２の電路切替部３２は、このタイミングで、開閉器制御部３８ｂを介して、第１、第２の開閉器１１、１２をＯＦＦにすると共に（Ｓ１３）、第４、第５の開閉器１４、１５（及び第３の開閉器１３）をＯＮにして（Ｓ１４）、使用する電路を第３の電路２３に切り替える。 Next, the storage battery management method by the storage battery management system 30 of this embodiment is demonstrated based on the flowchart shown in FIG. The charging state detection unit 38 a of the control device 38 detects the charging state (SOC) of each of the first and second storage batteries 1 and 2 charged and discharged by the charger / discharger 6. As shown in FIG. 7, the detected state of charge of the second storage battery 2 has decreased to a first charge state threshold SOC _th1 (for example, 80%) or less (YES in S11), and further, the first storage battery 1 When the state of charge is between the second state-of-charge threshold SOC _th2 (for example, 80%) and the third state-of-charge threshold SOC _th3 (for example, 100%) (YES in S12), the second electric circuit switching unit 32, at this timing, the first and second switches 11 and 12 are turned OFF via the switch control unit 38b (S13), and the fourth and fifth switches 14 and 15 (and the first switch 15). 3 switch 13) is turned ON (S14), and the electric circuit to be used is switched to the third electric circuit 23.

つまり、この場合、第３の電路２３を介して、第１及び第２の蓄電池１、２が充放電器６に直列に接続されると共に第１の蓄電池１に対して第２の蓄電池２が逆接続される。これによって、第１の蓄電池１の充電状態が減少する一方で、第２の蓄電池２の充電が開始される（Ｓ１５）。この後、第２の蓄電池２の充電状態が、第４の充電状態閾値ＳＯＣ_th4（例えば１００％）に到達したことが充電状態検出部３８ａによって検出された場合（Ｓ１６のＹＥＳ）、制御装置３８は、例えば充放電器６の稼働を停止させる（Ｓ１７）。 That is, in this case, the first and second storage batteries 1 and 2 are connected in series to the charger / discharger 6 via the third electrical path 23 and the second storage battery 2 is connected to the first storage battery 1. Reverse connected. Thereby, while the charge state of the 1st storage battery 1 reduces, charge of the 2nd storage battery 2 is started (S15). Thereafter, when the charge state detection unit 38a detects that the charge state of the second storage battery 2 has reached the fourth charge state threshold SOC _th4 (for example, 100%) (YES in S16), the control device 38 For example, the operation of the charger / discharger 6 is stopped (S17).

したがって、本実施形態の蓄電池管理システム３０によれば、第２の蓄電池２の充電状態を１００％にまで到達させることが可能なので、フル充電した第２の蓄電池を第１の蓄電池１に直列に接続して活用する際に、図３に例示したように、好適な出力電圧の特性を得ることができ、第１及び第２の蓄電池１、２の利用効率を向上させることができる。 Therefore, according to the storage battery management system 30 of the present embodiment, the state of charge of the second storage battery 2 can be reached to 100%, so the fully charged second storage battery is connected in series to the first storage battery 1. When connecting and utilizing, as illustrated in FIG. 3, it is possible to obtain suitable output voltage characteristics and improve the utilization efficiency of the first and second storage batteries 1 and 2.

以上、本発明のいくつかの実施形態を説明したが、これらの実施形態は、例として提示したものであり、発明の範囲を限定することは意図していない。これら新規な実施形態は、その他の様々な形態で実施されることが可能であり、発明の要旨を逸脱しない範囲で、種々の省略、置き換え、変更を行うことができる。これらの実施形態やその変形例は、発明の範囲や要旨に含まれると共に、特許請求の範囲に記載された発明とその均等の範囲に含まれる。 As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

１，４１…第１の蓄電池、２…第２の蓄電池、６…充放電器、８，３８…制御装置、８ａ…充電状態検出部（第１の充電状態検出部）、８ｂ，３８ｂ…開閉器制御部、１０，２０，３０…蓄電池管理システム、１０ａ，３０ａ…蓄電池管理装置、１１…第１の開閉器、１２…第２の開閉器、１３…第３の開閉器、１４…第４の開閉器、１５…第５の開閉器、２１…第１の電路、２２…第２の電路、２３…第３の電路、３１…電路切替部（第１の電路切替部）、３２…第２の電路切替部、３８ａ…充電状態検出部（第２の充電状態検出部）。 DESCRIPTION OF SYMBOLS 1,41 ... 1st storage battery, 2 ... 2nd storage battery, 6 ... Charge / discharge device, 8, 38 ... Control apparatus, 8a ... Charge state detection part (1st charge state detection part), 8b, 38b ... Opening and closing Control unit 10, 20, 30 ... storage battery management system, 10a, 30a ... storage battery management device, 11 ... first switch, 12 ... second switch, 13 ... third switch, 14 ... fourth 15 ... fifth switch, 21 ... first electric circuit, 22 ... second electric circuit, 23 ... third electric circuit, 31 ... electric circuit switching unit (first electric circuit switching unit), 32 ... first 2 electric circuit switching parts, 38a ... charge condition detection part (2nd charge condition detection part).

Claims

First and second storage batteries;
A charger / discharger for charging / discharging the first and second storage batteries;
A first electrical circuit connecting the first storage battery to the charger / discharger;
A second electrical circuit connecting the first and second storage batteries in series to the charger / discharger;
A charge state detection unit for detecting a charge state of the first storage battery charged and discharged by the charger / discharger;
An electric circuit switching unit that switches the electric circuit to be used to one of the first and second electric circuits based on the charging state of the first storage battery detected by the charging state detection unit;
A storage battery management system comprising:

The first and second storage batteries include a plurality of battery cells connected in series and / or in parallel,
The first storage battery and the second storage battery are different in at least one of the number of arrangement of the battery cells in the series direction and the number of arrangement of the battery cells in the parallel direction.
The storage battery management system according to claim 1.

The second storage battery is configured such that the total number of the battery cells provided is less than that of the first storage battery.
The storage battery management system according to claim 2.

A second charge state detection unit for detecting a charge state of each of the first and second storage batteries charged and discharged by the charger / discharger;
A third electrical circuit for connecting the first and second storage batteries in series to the charger / discharger and connecting the second storage battery to the first storage battery in a reverse connection relationship;
A second switch that switches the electric circuit to be used to one of the first to third electric circuits based on the charged state of each of the first and second storage batteries detected by the second charged state detector. An electric circuit switching unit;
The storage battery management system according to any one of claims 1 to 3, further comprising:

A first electrical circuit connecting the first storage battery to a charger / discharger for charging and discharging the first and second storage batteries;
A second electrical circuit connecting the first and second storage batteries in series to the charger / discharger;
A charge state detection unit for detecting a charge state of the first storage battery charged and discharged by the charger / discharger;
An electric circuit switching unit that switches the electric circuit to be used to one of the first and second electric circuits based on the charging state of the first storage battery detected by the charging state detection unit;
A storage battery management device.

A first electric circuit for connecting the first storage battery to a charger / discharger for charging / discharging the first and second storage batteries, and a first circuit for connecting the first and second storage batteries in series to the charger / discharger. A storage battery management method using two electric circuits,
Detecting the state of charge of the first storage battery charged and discharged by the charger / discharger;
Switching the electric circuit to be used to one of the first and second electric circuits based on the detected state of charge of the first storage battery;
A storage battery management method.