JP2004039506A - Fuel cell system - Google Patents

Fuel cell system Download PDF

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JP2004039506A
JP2004039506A JP2002196648A JP2002196648A JP2004039506A JP 2004039506 A JP2004039506 A JP 2004039506A JP 2002196648 A JP2002196648 A JP 2002196648A JP 2002196648 A JP2002196648 A JP 2002196648A JP 2004039506 A JP2004039506 A JP 2004039506A
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Japan
Prior art keywords
power
fuel cell
storage battery
load
supply system
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JP2002196648A
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Japanese (ja)
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Kenji Kubo
久保　謙二
Tomonori Hagio
萩尾　友紀
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Hitachi Appliances Inc
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Hitachi Home and Life Solutions Inc
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    • 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
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

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Abstract

<P>PROBLEM TO BE SOLVED: To provide a grid-connected power system suitable for a system composed by combining power peak shift by storage into a storage battery and storage of nighttime power with peak power feed to a load having a value rapidly changing while preventing power stored in a power storage system from being reversely fed to the system, in a system with a fuel cell combined with power storage. <P>SOLUTION: This fuel cell system is equipped with: the fuel cell; the storage battery; a first power converter connected between the fuel cell and a power supply system for converting D.C. into A.C.; and a second power converter connected between the fuel cell and the storage battery for discharging power of the storage battery and for charging the storage battery from a power line between the fuel cell and the storage battery. The fuel cell system is provided with functions for feeding power to the load from the power supply system when required power for the load connected to the power system exceeds the generated power of the fuel cell; for feeding power to the load from the storage battery so as to prevent the power from the power supply system from exceeding a predetermined value; and for charging the storage battery with the power of the fuel cell when the consumption power of the load is smaller than the generation amount of the fuel cell. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、燃料電池発電システムと蓄電システムとを併用した系統連系形の電源システムに関する。
【０００２】
【従来の技術】
燃料電池発電システムは、燃料電池の発電電力を負荷に供給すると共に、余剰電力を電源系統に蓄電できる。一方、電力ピークシフト手段として、蓄電池を用い、電気料金の安い夜間電力を蓄電し、電力の利用度の大きい昼間に使用する蓄電システムが知られている。
【０００３】
分散電源と蓄電とを組み合わせたシステムとして、特開平１０−２０１１２９号公報に記載されているように、太陽光発電の入力に対して開閉器を介して蓄電池を接続し、受電端の電力検出値が所定の値を超えているとき、蓄電池に接続された開閉器をオンし、蓄電池から電力を放電させる方式がある。これにより、受電端の電力が所定の値を超えないようにする。
【０００４】
【発明が解決しようとする課題】
しかし、本方式では、太陽光発電の直流電力と蓄電池の直流電力とを、同じ電力変換器で交流電力に変換して電源系統に出力する。このため、分散電源の電力と蓄電池からの放電電力をと独立に制御できず、最大電力追従制御のような太陽光発電に固有な制御と、蓄電池の放電制御とを両立するのが難しいという問題点がある。
【０００５】
本発明の目的は、燃料電池と蓄電とを組み合わせたシステムにおいて、蓄電池への蓄電と、夜間電力の蓄電による電力ピークシフト、および蓄電システムに蓄積された電力を系統に逆潮流しないようにしながら負荷の大きさが急峻に変動する負荷へのピーク電力供給とを組み合わせたシステムに好適な系統連系形電源システムを提供することにある。
【０００６】
【課題を解決するための手段】
上記目的は、燃料電池と、蓄電池と、前記燃料電池と電源系統との間に接続され、直流を交流に変換する第１の電力変換器と、前記燃料電池と前記蓄電池との間に接続され、前記蓄電池の電力を放電する第２の電力変換器とを備え、前記電力系統に接続された負荷の要求電力が前記燃料電池の発電電力を超えた場合、前記電源系統から電力を前記負荷に供給し、前記電源系統からの電力が予め決められた電力を超えないように前記蓄電池から電力を前記負荷に供給する機能を備えた燃料電池システムとすることにより達成される。
【０００７】
また、上記目的は、燃料電池と、蓄電池と、前記燃料電池と電源系統との間に接続され、直流を交流に変換する第１の電力変換器と、前記燃料電池と前記蓄電池との間に接続され、前記蓄電池の電力を放電し、前記燃料電池と前記蓄電池との間の電力線から前記蓄電池に電力を充電する第２の電力変換器とを備え、前記電力系統に接続された負荷の要求電力が前記燃料電池の発電電力を超えた場合、前記電源系統から電力を前記負荷に供給し、前記電源系統からの電力が予め決められた電力を超えないように前記蓄電池から電力を前記負荷に供給し、前記燃料電池の発電量よりも前記負荷の消費電力が小さいとき前記燃料電池の電力を前記蓄電池に充電する機能を備えた燃料電池システムとすることにより達成される。
【０００８】
負荷への電力の供給は基本的に燃料電池が行う。そして、負荷の消費電力が燃料電池の発電量を超えた場合、電力系統から電力を供給する。さらに、蓄電池から放電される電力は、電源系統から負荷に供給される電力が、所定の大きさを超えた場合に、蓄電池から電力を放電し、その放電電力は、電源系統側の電力が、所定の大きさを超えないように制御される。このため、燃料電池発電電力が負荷の消費電力より大きく、蓄電池に蓄電されるような条件では、電源系統側の電力が所定の設定値以下となるため、蓄電池からの放電はない。
【０００９】
また、燃料電池の発電電力と負荷電力との差分が、蓄電池に対して蓄電される。これにより、燃料電池と蓄電池を組み合わせたシステムであっても、燃料電池の発電電力の大きさに係わらず、蓄電池に蓄電される電力は、燃料電池発電電力の余剰分のみとなり、蓄電池に蓄電された電力が系統に逆潮流されることはない。
【００１０】
また、電源系統側の電力を常時監視し、燃料電池発電電力分とは独立して、蓄電池からの放電電力を制御するため、高精度に電源系統の電力ピークを抑制できる。
【００１１】
【発明の実施の形態】
以下、本発明の第１の実施例を図１により説明する。電源系統１から負荷３に対して系統電力が供給されている。配線２の分電盤４に電源システム５が接続されており、また、電源システム５は、逆流防止ダイオード８を介して燃料電池７からの発電電力を入力する。電源システム５は、平滑コンデンサ５０１、第１の電力変換器である双方向ＡＣ／ＤＣ変換器５０２、蓄電池５０６、第２の電力変換器である双方向ＤＣ／ＤＣ変換器５０５、開閉器５０３、系統電圧検出用トランス５０４、交流電流検出器６からの検出信号と系統電圧検出用トランス５０４からの検出信号とから系統電力を演算する電力検出手段５０７、電力検出手段５０７の演算結果に応じ蓄電池５０６からの放電あるいは充電を制御するための充放電制御手段５０８から構成される。
【００１２】
ここで、双方向ＤＣ／ＤＣ変換器５０５は、充放電制御手段５０８の演算結果に基づき、蓄電池５０６からの放電電流や蓄電池５０６への充電電流を制御する。一方、双方向ＡＣ／ＤＣ変換器５０２は、燃料電池７からの発電電力を交流電力に変換し電源系統１に出力する。また、双方向ＡＣ／ＤＣ変換器５０２は、平滑コンデンサ５０１の直流電圧Ｖｄｃを調整する機能を持っており、この平滑コンデンサ５０１の直流電圧を調整することで、燃料電池７から最大電力を取り出せるように制御する。なお、この第１の電力変換器５０５は、必ずしも双方向でなくても良い。
【００１３】
分電盤４に設けた交流電流検出器６により検出された電源系統側の交流電流は、電力検出５０７において、系統電圧検出用トランス５０４の検出信号と乗算され、電源系統側の電力検出値となる。充放電制御５０８では、電力検出値の大きさに応じ、蓄電池５０６からの放電電流、あるいは、蓄電池５０６への充電電流を制御する。蓄電池５０６からの放電、あるいは充電は、双方向ＤＣ／ＤＣ変換器５０５により実行される。ここで、平滑コンデンサ５０１の直流電圧Ｖｄｃは、双方向ＡＣ／ＤＣ変換器５０２により、燃料電池７から取り出せる電力が最大になるように調整される。双方向ＤＣ／ＤＣ変換器５０５は、調整されたＶｄｃ値に対して、蓄電池５０６からの放電、あるいは充電を行う。
【００１４】
次に、双方向ＡＣ／ＤＣ変換器５０２の構成を図２に示す。４個のＩＧＢＴ（Ｉｎｓｕｌａｔｅｄ　Ｇａｔｅ　Ｂｉｐｏｌａｒ　Ｔｒａｎｓｉｓｔｏｒ）をフルブリッジ接続した電力変換器５０２１、交流リアクトル５０２２、フィルタコンデンサ５０２３、電力変換器５０２１の相電流を検出するための電流検出器５０２４、相電流を検出して電力変換器５０２１へのゲートパルス信号を出力する交流電流制御手段５０２５、平滑コンデンサ５０１１，５０１２の直列電圧Ｖｄｃを検出し、その値が所定の値となるように制御する直流電圧制御手段５０２６、電力変換器５０２１の相電流と系統電圧の検出値を用い、電力変換器５０２１から出力あるいは入力する電力を演算する電力演算手段５０２７から構成される。電力変換器５０２１は単相３線出力で、平滑コンデンサ５０１１，５０１２の中点Ｎを単相３線の中点として出力する。
【００１５】
また、双方向ＤＣ／ＤＣ変換器５０５の構成を図３に示す。２個のＩＧＢＴをハーフブリッジ接続した電力変換器５０５１、直流リアクトル５０５２、平滑コンデンサ５０５３、電流検出器５０５４、電流制御手段５０５５から構成されている。電流制御手段５０５５は、電力変換器５０５１のゲート信号を制御し、直列接続された平滑コンデンサ５０１１、５０１２と蓄電池５０６との間で、双方向（充電／放電）に電流を制御する。
【００１６】
いま、図１に示す構成において、電源系統１からの配線２に接続された負荷３の電力が、燃料電池７の発電電力より大きい場合、燃料電池７の出力電力は、負荷３で使われ、不足する電力分は、電源系統側１から供給を受ける。電源系統１の電力を検出し、その検出値が所定のしきい値を超えないように、蓄電池５０６の電力を電源系統１に出力することで、負荷３の電力から燃料電池７の発電電力を引いた値がしきい値を超える分だけ、蓄電池５０６から出力することができる。ここで、充放電制御手段５０８は、電力検出手段５０７で検出された電源系統側電力から所定のしきい値を引いた値がゼロになるように、双方向ＤＣ／ＤＣ変換器を制御して蓄電池５０６からの放電電流を制御する。
【００１７】
一方、燃料電池７の発電電力が負荷３の電力より大きい場合には、負荷で消費される電力に対する余剰分は蓄電池に蓄電される。この場合は、電力検出手段５０７により検出される電源系統側の電力は負の値となり、所定のしきい値以下であるため、蓄電池５０６からの放電は行われない。
【００１８】
このように、電源系統側の電力を検出し、その値に応じて、蓄電池５０６からの放電電力を制御することにより、燃料電池７の発電状態や、負荷３の負荷状態に係わらず、電源系統側の電力を所定のしきい値を超えないように、電力ピーク補償できる。
【００１９】
以上、述べたように、本実施例によれば、燃料電池と蓄電とを組み合わせたシステムにおいて、電源系統１側の電力を交流電流検出器６より検出し、電源系統１の電力が所定の上限値を超えないように、蓄電池５０６からの放電電力を制御する。このため、燃料電池７の発電電力が蓄電されるような場合であっても、蓄電池５０６からの放電は、電源系統１から購入する電力が所定の値以上の場合に行う。この状態では、電力の蓄電はないので、蓄電池５０６からの放電電力が逆潮流されることはない。また、燃料電池７の発電電力が得られる場合でも、負荷電力が大きく購入電力が大きくなる場合には、蓄電池５０６から放電することで、電気料金の安い夜間電力を負荷電力のピーク時に使用することができるという利点もある。
【００２０】
また、電源系統の電力値、電源系統への交流電力出力値、電源系統からの交流電力入力値、蓄電手段から放電される電力値、蓄電手段に充電される電力値を演算し、表示器に表示することで、蓄電池５０６からのピークカット放電運転をモニタすることができ、本システムの導入効果を示すことができる。また、各電力値を積算して電力量として表示することで、月間や年間のピークカット電力量を表示することができる。また、それらの値を外部からモニタできるようにすることで、本システムの導入による改善効果を数値として管理することができる。
【００２１】
本発明による第２の実施例の構成を図４に示す。第１の実施例との相違点は、燃料電池７の出力電圧を、ＤＣ／ＤＣ変換器５０９を用いて昇圧させた出力を、平滑コンデンサ５０１、および双方向ＤＣ／ＤＣに供給していることにある。これにより、燃料電池７の出力電圧が低い場合でも、ＤＣ／ＤＣ変換器５０９により燃料電池電圧を調整し、双方向ＡＣ／ＤＣ変換器５０２で交流電力に変換できる。これにより、燃料電池発電システムを広い運転領域で稼動させることができる。このとき、蓄電池５０６からの放電電力は、第１の実施例と同様に、双方向ＤＣ／ＤＣ変換器５０５により実行される。
【００２２】
以上、本実施例によれば、燃料電池発電システムを広範な運転状態で動作させることができ、蓄電池５０６による電力ピークカット補償の利用範囲を拡大することができる。
【００２３】
【発明の効果】
本発明によれば、燃料電池と蓄電とを組み合わせたシステムにおいて、蓄電池への蓄電と、夜間電力の蓄電による電力ピークシフト、および蓄電システムに蓄積された電力を系統に逆潮流しないようにしながら負荷の大きさが急峻に変動する負荷へのピーク電力供給とを組み合わせたシステムに好適な系統連系形電源システムを提供することができる。
【図面の簡単な説明】
【図１】第１の実施例による構成図。
【図２】双方向ＡＣ／ＤＣ変換器の構成図。
【図３】双方向ＤＣ／ＤＣ変換器の構成図。
【図４】第２の実施例の構成図。
【符号の説明】
１…電源系統、３…負荷、４…分電盤、５…電源システム、６…交流電流検出器、７…燃料電池、５０２…双方向ＡＣ／ＤＣ変換器、５０５…双方向ＡＣ／ＤＣ変換器、５０６…蓄電池、９…表示器。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power supply system of a system interconnection type using both a fuel cell power generation system and a power storage system.
[0002]
[Prior art]
The fuel cell power generation system can supply the power generated by the fuel cell to the load and store the surplus power in the power supply system. On the other hand, there is known a power storage system that uses a storage battery as power peak shift means, stores nighttime power at a low electricity rate, and uses the power during the daytime when power usage is high.
[0003]
As described in Japanese Patent Application Laid-Open No. H10-201129, a storage battery is connected to a solar power generation input via a switch, and a power detection value at a power receiving end is described as a system combining a distributed power supply and a power storage. There is a method in which a switch connected to a storage battery is turned on when the value exceeds a predetermined value to discharge power from the storage battery. This prevents the power at the power receiving end from exceeding a predetermined value.
[0004]
[Problems to be solved by the invention]
However, in this method, the DC power of the photovoltaic power generation and the DC power of the storage battery are converted into AC power by the same power converter and output to the power supply system. For this reason, the power of the distributed power source and the discharge power from the storage battery cannot be controlled independently of each other, and it is difficult to achieve both control unique to solar power generation such as maximum power tracking control and discharge control of the storage battery. There are points.
[0005]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a system in which a fuel cell and a power storage device are combined, in which power storage in the storage battery and power peak shift due to storage of nighttime power, and load while preventing power stored in the power storage system from flowing back to the system. It is an object of the present invention to provide a system interconnection type power supply system suitable for a system in which peak power supply to a load whose magnitude fluctuates rapidly is combined.
[0006]
[Means for Solving the Problems]
The above object is achieved by connecting a fuel cell, a storage battery, a first power converter that is connected between the fuel cell and a power supply system and converts direct current to alternating current, and is connected between the fuel cell and the storage battery. A second power converter that discharges the power of the storage battery, and when the required power of a load connected to the power system exceeds the power generated by the fuel cell, the power from the power system to the load. This is achieved by providing a fuel cell system having a function of supplying power from the power supply system to the load so that the power from the power supply system does not exceed a predetermined power.
[0007]
Further, the object is to provide a fuel cell, a storage battery, a first power converter that is connected between the fuel cell and a power supply system, and converts a direct current into an alternating current, and between the fuel cell and the storage battery. And a second power converter connected to the power system for discharging power from the storage battery and charging the storage battery with power from a power line between the fuel cell and the storage battery. When the power exceeds the power generated by the fuel cell, the power is supplied from the power supply system to the load, and the power from the storage battery is supplied to the load so that the power from the power supply system does not exceed a predetermined power. This is achieved by providing a fuel cell system having a function of supplying the power of the fuel cell to the storage battery when the power consumption of the load is smaller than the power generation amount of the fuel cell.
[0008]
The power supply to the load is basically performed by the fuel cell. When the power consumption of the load exceeds the amount of power generated by the fuel cell, power is supplied from the power system. Further, the electric power discharged from the storage battery discharges power from the storage battery when the power supplied from the power supply system to the load exceeds a predetermined magnitude, and the discharged power is the power on the power supply system side, Control is performed so as not to exceed a predetermined size. Therefore, under the condition that the power generated by the fuel cell is larger than the power consumption of the load and stored in the storage battery, the power on the power supply system side is equal to or less than the predetermined set value, and the storage battery does not discharge.
[0009]
The difference between the power generated by the fuel cell and the load power is stored in the storage battery. Thus, even in a system in which the fuel cell and the storage battery are combined, the power stored in the storage battery is only a surplus of the fuel cell power generation, regardless of the amount of power generated by the fuel cell, and is stored in the storage battery. The power flow will not flow back to the grid.
[0010]
Further, since the power on the power supply system side is constantly monitored and the discharge power from the storage battery is controlled independently of the power generated by the fuel cell, the power peak of the power supply system can be suppressed with high accuracy.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIG. System power is supplied from the power system 1 to the load 3. The power supply system 5 is connected to the distribution board 4 of the wiring 2, and the power supply system 5 inputs the power generated from the fuel cell 7 via the backflow prevention diode 8. The power supply system 5 includes a smoothing capacitor 501, a bidirectional AC / DC converter 502 as a first power converter, a storage battery 506, a bidirectional DC / DC converter 505 as a second power converter, a switch 503, System voltage detection transformer 504, power detection means 507 for calculating system power from a detection signal from AC current detector 6 and a detection signal from system voltage detection transformer 504, and storage battery 506 according to the calculation result of power detection means 507. Charge / discharge control means 508 for controlling discharge or charge from the battery.
[0012]
Here, the bidirectional DC / DC converter 505 controls the discharge current from the storage battery 506 and the charging current to the storage battery 506 based on the calculation result of the charge / discharge control unit 508. On the other hand, bidirectional AC / DC converter 502 converts the power generated from fuel cell 7 into AC power and outputs it to power supply system 1. The bidirectional AC / DC converter 502 has a function of adjusting the DC voltage Vdc of the smoothing capacitor 501. By adjusting the DC voltage of the smoothing capacitor 501, the maximum power can be extracted from the fuel cell 7. To control. The first power converter 505 does not necessarily have to be bidirectional.
[0013]
The AC current on the power supply system side detected by the AC current detector 6 provided on the distribution board 4 is multiplied by a detection signal of the system voltage detection transformer 504 in a power detection 507 to obtain a power detection value on the power supply system side. Become. The charge / discharge control 508 controls a discharge current from the storage battery 506 or a charging current to the storage battery 506 according to the magnitude of the detected power value. Discharge or charging from the storage battery 506 is executed by the bidirectional DC / DC converter 505. Here, the DC voltage Vdc of the smoothing capacitor 501 is adjusted by the bidirectional AC / DC converter 502 so that the power that can be extracted from the fuel cell 7 is maximized. The bidirectional DC / DC converter 505 discharges or charges the storage battery 506 with respect to the adjusted Vdc value.
[0014]
Next, the configuration of the bidirectional AC / DC converter 502 is shown in FIG. A power converter 5021 in which four IGBTs (Insulated Gate Bipolar Transistors) are connected in full bridge, an AC reactor 5022, a filter capacitor 5023, a current detector 5024 for detecting a phase current of the power converter 5021, and a phase current are detected. An AC current control means 5025 for outputting a gate pulse signal to the power converter 5021, a DC voltage control means 5026 for detecting a series voltage Vdc of the smoothing capacitors 5011 and 5012, and controlling the value to a predetermined value. The power converter 5021 includes a power calculation unit 5027 that calculates the power output or input from the power converter 5021 using the phase current of the power converter 5021 and the detected value of the system voltage. The power converter 5021 is a single-phase three-wire output, and outputs the midpoint N of the smoothing capacitors 5011 and 5012 as the midpoint of the single-phase three-wire.
[0015]
FIG. 3 shows the configuration of the bidirectional DC / DC converter 505. It comprises a power converter 5051 in which two IGBTs are half-bridge connected, a DC reactor 5052, a smoothing capacitor 5053, a current detector 5054, and a current control means 5055. The current control means 5055 controls the gate signal of the power converter 5051, and controls the current bidirectionally (charge / discharge) between the storage capacitors 506 and the smoothing capacitors 5011 and 5012 connected in series.
[0016]
Now, in the configuration shown in FIG. 1, if the power of the load 3 connected to the wiring 2 from the power supply system 1 is larger than the power generated by the fuel cell 7, the output power of the fuel cell 7 is used by the load 3. Insufficient power is supplied from the power supply system side 1. By detecting the power of the power supply system 1 and outputting the power of the storage battery 506 to the power supply system 1 so that the detected value does not exceed a predetermined threshold value, the power generated by the fuel cell 7 is converted from the power of the load 3 by the power. Only the amount by which the subtracted value exceeds the threshold value can be output from the storage battery 506. Here, the charge / discharge control unit 508 controls the bidirectional DC / DC converter so that a value obtained by subtracting a predetermined threshold value from the power supply side power detected by the power detection unit 507 becomes zero. The discharge current from the storage battery 506 is controlled.
[0017]
On the other hand, when the power generated by the fuel cell 7 is larger than the power of the load 3, a surplus of the power consumed by the load is stored in the storage battery. In this case, since the power on the power supply system side detected by the power detection unit 507 has a negative value and is equal to or less than a predetermined threshold value, the storage battery 506 is not discharged.
[0018]
As described above, by detecting the power on the power supply system side and controlling the discharge power from the storage battery 506 according to the value, the power supply system can be operated regardless of the power generation state of the fuel cell 7 or the load state of the load 3. Power peak compensation can be performed so that the power on the side does not exceed a predetermined threshold.
[0019]
As described above, according to the present embodiment, in the system in which the fuel cell and the power storage are combined, the power of the power supply system 1 is detected by the AC current detector 6 and the power of the power supply system 1 is set to the predetermined upper limit. The discharge power from storage battery 506 is controlled so as not to exceed the value. For this reason, even when the power generated by the fuel cell 7 is stored, the discharge from the storage battery 506 is performed when the power purchased from the power supply system 1 is equal to or more than a predetermined value. In this state, power is not stored, so that the discharged power from storage battery 506 does not flow backward. Even when the power generated by the fuel cell 7 can be obtained, when the load power is large and the purchased power is large, the nighttime power with a low electricity rate can be used at the peak load power by discharging from the storage battery 506. There is also an advantage that can be.
[0020]
Also, the power value of the power supply system, the AC power output value to the power supply system, the AC power input value from the power supply system, the power value discharged from the power storage means, and the power value charged to the power storage means are calculated and displayed on the display. By displaying, the peak cut discharge operation from the storage battery 506 can be monitored, and the introduction effect of the present system can be shown. In addition, by integrating each power value and displaying it as a power amount, a monthly or yearly peak cut power amount can be displayed. In addition, by enabling those values to be monitored from the outside, the improvement effect of the introduction of the present system can be managed as a numerical value.
[0021]
FIG. 4 shows the configuration of the second embodiment according to the present invention. The difference from the first embodiment is that an output obtained by boosting the output voltage of the fuel cell 7 using the DC / DC converter 509 is supplied to the smoothing capacitor 501 and the bidirectional DC / DC. It is in. Thus, even when the output voltage of the fuel cell 7 is low, the fuel cell voltage can be adjusted by the DC / DC converter 509 and converted into AC power by the bidirectional AC / DC converter 502. Thereby, the fuel cell power generation system can be operated in a wide operation range. At this time, the discharge power from the storage battery 506 is executed by the bidirectional DC / DC converter 505 as in the first embodiment.
[0022]
As described above, according to the present embodiment, the fuel cell power generation system can be operated in a wide range of operating states, and the range of use of the power peak cut compensation by the storage battery 506 can be expanded.
[0023]
【The invention's effect】
According to the present invention, in a system in which a fuel cell and a power storage are combined, power storage in the storage battery, power peak shift due to storage of nighttime power, and load while preventing power stored in the power storage system from flowing back to the system. It is possible to provide a grid-connected power supply system suitable for a system that combines peak power supply to a load whose magnitude fluctuates sharply.
[Brief description of the drawings]
FIG. 1 is a configuration diagram according to a first embodiment.
FIG. 2 is a configuration diagram of a bidirectional AC / DC converter.
FIG. 3 is a configuration diagram of a bidirectional DC / DC converter.
FIG. 4 is a configuration diagram of a second embodiment.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 power supply system 3 load 4 distribution board 5 power supply system 6 alternating current detector 7 fuel cell 502 bidirectional AC / DC converter 505 bidirectional AC / DC conversion 506: storage battery, 9: display.

Claims (5)

燃料電池と、蓄電池と、前記燃料電池と電源系統との間に接続され、直流を交流に変換する第１の電力変換器と、前記燃料電池と前記蓄電池との間に接続され、前記蓄電池の電力を放電する第２の電力変換器とを備え、前記電力系統に接続された負荷の要求電力が前記燃料電池の発電電力を超えた場合、前記電源系統から電力を前記負荷に供給し、前記電源系統からの電力が予め決められた電力を超えないように前記蓄電池から電力を前記負荷に供給する機能を備えた燃料電池システム。A fuel cell, a storage battery, a first power converter connected between the fuel cell and the power supply system for converting direct current to alternating current, and a first power converter connected between the fuel cell and the storage battery; A second power converter that discharges power, when the required power of a load connected to the power system exceeds the power generated by the fuel cell, supplies power from the power system to the load; A fuel cell system having a function of supplying power from the storage battery to the load so that power from a power supply system does not exceed predetermined power. 燃料電池と、蓄電池と、前記燃料電池と電源系統との間に接続され、直流を交流に変換する第１の電力変換器と、前記燃料電池と前記蓄電池との間に接続され、前記蓄電池の電力を放電し、前記燃料電池と前記蓄電池との間の電力線から前記蓄電池に電力を充電する第２の電力変換器とを備え、前記電力系統に接続された負荷の要求電力が前記燃料電池の発電電力を超えた場合、前記電源系統から電力を前記負荷に供給し、前記電源系統からの電力が予め決められた電力を超えないように前記蓄電池から電力を前記負荷に供給し、前記燃料電池の発電量よりも前記負荷の消費電力が小さいとき前記燃料電池の電力を前記蓄電池に充電する機能を備えた燃料電池システム。A fuel cell, a storage battery, a first power converter connected between the fuel cell and the power supply system for converting direct current to alternating current, and a first power converter connected between the fuel cell and the storage battery; A second power converter that discharges power and charges the storage battery with power from a power line between the fuel cell and the storage battery, and a required power of a load connected to the power system is a power supply of the fuel cell. When the generated power is exceeded, power is supplied from the power supply system to the load, and power is supplied from the storage battery to the load so that power from the power supply system does not exceed a predetermined power. A fuel cell system having a function of charging the storage battery with the power of the fuel cell when the power consumption of the load is smaller than the power generation amount of the fuel cell. 請求項１または２において、前記燃料電池の発電電力と前記蓄電手段の出力電力とを直流側で連系する燃料電池システム。3. The fuel cell system according to claim 1, wherein the power generated by the fuel cell and the output power of the power storage unit are interconnected on the DC side. 請求項１または２において、前記燃料電池の発電電力と前記蓄電手段の出力電力とを電源系統側で個別に連系する燃料電池システム。3. The fuel cell system according to claim 1, wherein the power generated by the fuel cell and the output power of the power storage unit are individually interconnected on a power system side. 4. 請求項１において、電源系統の電力値、電源系統への交流電力出力値、電源系統からの交流電力入力値、蓄電手段から放電される電力値、蓄電手段に充電される電力値、あるいは各電力値の積算値を計測、もしくは演算する機能を備え、それらの値を表示、もしくは外部からモニタできるようにした燃料電池システム。The power value of the power supply system, the AC power output value to the power supply system, the AC power input value from the power supply system, the power value discharged from the power storage means, the power value charged to the power storage means, or each power according to claim 1. A fuel cell system having a function of measuring or calculating an integrated value of a value, so that the value can be displayed or externally monitored.
JP2002196648A 2002-07-05 2002-07-05 Fuel cell system Pending JP2004039506A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006073503A (en) * 2004-08-06 2006-03-16 Sanyo Electric Co Ltd Fuel cell system
JP2006262613A (en) * 2005-03-16 2006-09-28 Meidensha Corp Power supply system, power supply method, and building
JP2009181824A (en) * 2008-01-31 2009-08-13 Aisin Seiki Co Ltd Fuel cell system
JP2009545944A (en) * 2006-08-04 2009-12-24 セレス インテレクチュアル プラパティ コンパニー リミテッド Power control for generator
US7946365B2 (en) 2006-02-03 2011-05-24 Honda Motor Co., Ltd. Control method for fuel cell vehicle, and fuel cell vehicle
JP7509010B2 (en) 2020-11-27 2024-07-02 株式会社アイシン Power System

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006073503A (en) * 2004-08-06 2006-03-16 Sanyo Electric Co Ltd Fuel cell system
US7767353B2 (en) 2004-08-06 2010-08-03 Sanyo Electric Co., Ltd. Fuel cell system
US8012638B2 (en) 2004-08-06 2011-09-06 Sanyo Electric Co. Ltd. Fuel cell system
JP2006262613A (en) * 2005-03-16 2006-09-28 Meidensha Corp Power supply system, power supply method, and building
JP4496112B2 (en) * 2005-03-16 2010-07-07 株式会社明電舎 Power supply system, power supply method, and building
US7946365B2 (en) 2006-02-03 2011-05-24 Honda Motor Co., Ltd. Control method for fuel cell vehicle, and fuel cell vehicle
JP2009545944A (en) * 2006-08-04 2009-12-24 セレス インテレクチュアル プラパティ コンパニー リミテッド Power control for generator
JP2009181824A (en) * 2008-01-31 2009-08-13 Aisin Seiki Co Ltd Fuel cell system
JP7509010B2 (en) 2020-11-27 2024-07-02 株式会社アイシン Power System

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