WO2018003581A1

WO2018003581A1 - Power storage system

Info

Publication number: WO2018003581A1
Application number: PCT/JP2017/022566
Authority: WO
Inventors: 博寿福田; 幸次 ▲高▼橋
Original assignee: 株式会社Ｇｓユアサ
Priority date: 2016-06-28
Filing date: 2017-06-19
Publication date: 2018-01-04
Also published as: JPWO2018003581A1; JP6870678B2

Abstract

A power storage system (100) is provided with: a first electric storage unit (101); a second electric storage unit (102); a switching unit (106) that selectably connects the first electric storage unit (101) or the second electric storage unit (102) to an external unit outside the power storage system (100); a second-electric-storage-unit control unit (102a) that uses a control power source (10) as a power source and that controls the second electric storage unit (102); and a control-power-source opening/closing unit (107) that connects or disconnects the second-electric-storage-unit control unit (102a) and the control power source (10). The control-power-source opening/closing unit (107) disconnects the second-electric-storage-unit control unit (102a) and the control power source (10) when the switching unit (106) connects the first electric storage unit (101) to an external unit outside the power storage system (100) and connects the second-electric-storage-unit control unit (102a) and the control power source (10) when the switching unit (106) connects the second electric storage unit (102) to an external unit outside the power storage system (100).

Description

Power storage system

The present invention relates to a power storage system including a plurality of power storage units.

Electric railways have proposed a technology that effectively uses regenerative power generated by trains. For example, Patent Document 1 describes an electric railway power system that charges a storage battery with power from a feeder circuit that supplies power to a train in an electric railway, and discharges the power from the storage battery to the feeder circuit. Electric power supplied from the substation and regenerative power of the train flow through the feeder circuit.

JP 2011-056996 A

In the electric railway power system described in Patent Document 1, only one system of storage batteries is provided. However, in order to perform stable power supply, it is desirable that a plurality of systems of storage batteries are provided.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power storage system that enables stable power supply by a plurality of power storage units.

In order to achieve the above object, a power storage system according to an aspect of the present invention is a power storage system, and includes a first power storage unit, a second power storage unit, and the first power storage unit or the second power storage unit. Is connected to the outside of the power storage system in a selectable manner, a second power storage unit control unit that controls the second power storage unit using a control power supply as a power source, the second power storage unit control unit, and the control A control power supply opening / closing unit that connects or disconnects the power supply, and the control power supply switching unit is configured such that when the switching unit connects the first power storage unit to the outside of the power storage system, the second power storage unit When the control unit is disconnected from the control power source and the switching unit connects the second power storage unit to the outside of the power storage system, the second power storage unit control unit and the control power source are connected. .

The power storage system according to the present invention enables stable power supply by a plurality of power storage units.

FIG. 1 is a schematic diagram illustrating an application example of the power storage system according to the embodiment. FIG. 2 is a block diagram showing a configuration of the power storage system of FIG. FIG. 3 is a flowchart for explaining the operation of the power storage system of FIG.

In the electric railway power system described in Patent Document 1, only one storage battery is provided. For this reason, there is a possibility that the storage battery cannot supply sufficient power to the feeder circuit when the power supplied to the feeder circuit is greatly reduced due to an abnormality in a substation that supplies power to the feeder circuit. is there. This can cause the train to stop at undesired places where passengers cannot get on and off, such as between stations and on bridges. Thus, in order to perform stable power supply, it is desirable to provide a plurality of storage batteries. The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power storage system that enables stable power supply by a plurality of power storage units.

According to this, when the switching unit connects the first power storage unit to the outside of the power storage system, the second power storage unit control unit and the control power supply are cut off, and the switching unit connects the second power storage unit to the power storage system. When connecting to the outside, the second power storage unit control unit and the control power source are connected. That is, when the second power storage unit is connected to the outside, it is necessary to connect the second power storage unit control unit and the control power source in order to control the second power storage unit. When connected to the outside, since it is not necessary to control the second power storage unit, the second power storage unit control unit and the control power source can be shut off. Here, when the second power storage unit control unit and the control power source are connected, the second power storage unit and the second power storage unit control unit are electrically connected, so that self-discharge from the second power storage unit (Spontaneous discharge) may occur. For this reason, when a 1st electrical storage part is connected to the said exterior, the self-discharge from a 2nd electrical storage part can be suppressed by interrupting | blocking a 2nd electrical storage part control part and a power supply for control. Thus, in an electric power storage system including a plurality of power storage units, stable power supply can be performed by suppressing self-discharge from the power storage unit.

In addition, the shut-off operation of the control power supply switching unit may be interlocked with the connection operation between the first power storage unit and the outside of the power storage system by the switching unit.

According to this, since the shutoff operation between the second power storage unit control unit and the control power supply is linked with the connection operation between the first power storage unit and the outside of the power storage system, the first power storage unit and the power storage system outside The self-discharge of the second power storage unit can be suppressed immediately after the connection with.

Further, the connection operation of the control power supply opening / closing unit may be interlocked with the connection operation between the second power storage unit and the outside of the power storage system by the switching unit.

According to this, since the connection operation between the second power storage unit control unit and the control power supply is linked with the connection operation between the second power storage unit and the outside of the power storage system, the second power storage unit and the outside of the power storage system The second power storage unit control unit can be operated immediately after the connection.

Further, the first power storage unit has characteristics suitable for repeated charging and discharging than the second power storage unit, and the second power storage unit has higher capacity characteristics than the first power storage unit. Good.

According to this, since the first power storage unit has characteristics suitable for repeated charging and discharging, and the second power storage unit has characteristics of higher capacity (high energy density) than the first power storage unit, By using the first power storage unit as a power source for normal use and using the second power storage unit as an emergency power source, the first power storage unit can be used in accordance with the characteristics of the first power storage unit and the second power storage unit.

Further, the first power storage unit may have higher rate characteristics than the second power storage unit.

According to this, since the first power storage unit has a higher rate characteristic than the second power storage unit, for example, by using the first power storage unit as a power source for normal use, the first power storage unit is used in accordance with the characteristics of the first power storage unit. be able to.

The switching unit can select the first power storage unit or the second power storage unit as a vehicle that generates regenerative power outside the power storage system and a vehicle power source that supplies power to the vehicle. You may decide to connect to.

According to this, since the first power storage unit or the second power storage unit is connected to the vehicle that generates regenerative power and the power source for the vehicle that supplies power to the vehicle, the storage of the regenerative power of the vehicle and the vehicle The stored electric power can be supplied to the.

The switching unit connects the outside of the power storage system and the first power storage unit during normal operation of the vehicle power source, and connects the outside of the power storage system and the outside during abnormal operation of the vehicle power source. The second power storage unit may be connected.

According to this, since the outside of the power storage system and the second power storage unit are connected at the time of abnormal operation of the vehicle power source, for example, the second power storage unit having high capacity characteristics can be used as an emergency power source. .

Further, the switching unit may connect the outside of the power storage system and the second power storage unit under a predetermined condition, and charge the second power storage unit to a predetermined power storage amount.

According to this, the switching unit connects the outside of the power storage system and the second power storage unit under a predetermined condition, and charges and maintains the second power storage unit at a predetermined power storage amount. When using this, sufficient power supply can be obtained from the second power storage unit.

Hereinafter, a power storage system according to an embodiment of the present invention will be described with reference to the drawings. It should be noted that each of the embodiments described below shows a comprehensive or specific example. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, processes (steps), order of processes, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept are described as optional constituent elements.

In addition, each figure in the attached drawings is a schematic diagram and is not necessarily illustrated strictly. Furthermore, in each figure, the same code | symbol is attached | subjected about the same or similar component. In the following description of the embodiments, expressions with “substantially” such as substantially parallel and substantially orthogonal may be used. For example, “substantially parallel” not only means completely parallel, but also means substantially parallel, that is, including a difference of, for example, several percent. The same applies to expressions involving other “abbreviations”.

[Embodiment]
A configuration of the power storage system 100 according to the embodiment of the present invention will be described. In the present embodiment, an example in which the power storage system 100 is applied to a power system of a vehicle, specifically, a power system of an electric railway will be described. The electric railway is an electric railway that uses an overhead line for power transmission for power supply, an electric railway that uses two rails for power transmission for power supply, an electric railway that uses a third rail added to the two rails for power supply, An electric railway such as a monorail using one rail for power supply, an electric railway driven by a linear motor, and the like can be included.

FIG. 1 is a schematic diagram showing an application example of the power storage system 100 according to the present embodiment. Referring to FIG. 1, an electric railway power system (hereinafter referred to as a vehicle power system) 1 outside the power storage system 100 includes a substation 2, a plurality of trains 3 as electric vehicles, and a train 3. Including a power line 4 and the like. The power line 4 is a linearly arranged power supply body such as an overhead wire, a rail, and an electromagnet for a linear motor. The substation 2 converts the three-phase AC power sent from the power plant 6 of the power company into DC power, and further steps down and rectifies the voltage to a voltage usable by the train 3 such as 1500V. Furthermore, the substation 2 supplies DC power to the power line 4. The train 3 is powered by using DC power supplied via the power line 4. Further, the train 3 is a vehicle that can regenerate power, and is configured to generate regenerative power during braking, and supplies the generated regenerative power to the power line 4. The regenerative power supplied to the power line 4 can be used by other trains 3 and the like. As an example of the regenerative power, there is a regenerative power by a regenerative brake that rotates a motor as a generator to generate power when the train 3 is braked. Here, the train 3 is an example of a vehicle that generates regenerative power, and the substation 2 is an example of a vehicle power source that supplies power to the vehicle.

The power storage system 100 is electrically connected to the power line 4. It is electrically connected to the vehicle power system 1 via the power line 4. In other words, the power storage system 100 is electrically connected to the substation 2 and the train 3 via the power line 4. The power storage system 100 is configured to receive and store surplus power in the vehicle power system 1 and to supply the stored power to the vehicle power system 1. For example, the power storage system 100 may be disposed at the station 5 disposed along the track of the train 3 or may be provided in the substation 2. Or the electric power storage system 100 may be arrange | positioned in the place along the track between the stations 5, the vehicle base of the train 3, etc. FIG.

The configuration of the power storage system 100 will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of the power storage system 100 of FIG. The power storage system 100 includes a first power storage unit 101 and a second power storage unit 102 that form two power storage units. Each of the first power storage unit 101 and the second power storage unit 102 includes a plurality of battery cells made of a chargeable / dischargeable secondary battery. The secondary battery constituting the battery cell is a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery, for example.

The battery cell of the 1st electrical storage part 101 has the characteristic in which the fall of ability, such as durability and performance sustainability, was suppressed with respect to repeated charging / discharging rather than the battery cell of the 2nd electrical storage part 102. That is, the battery cell of the first power storage unit 101 has characteristics (higher rate characteristics higher than the battery cell of the second power storage unit 102) suitable for input / output of a large current than the battery cell of the second power storage unit 102. ing. In the present embodiment, first power storage unit 101 can be used during normal operation of vehicular power system 1 such as substation 2.

The battery cell of the second power storage unit 102 has a higher energy density than the battery cell of the first power storage unit 101, that is, has a high capacity. In the present embodiment, second power storage unit 102 can be used during abnormal operation of vehicle power system 1 such as substation 2. For example, the first power storage unit 101 is used while being charged and maintained at an SOC (State （Of Charge) of about 50%, while the second power storage unit 102 is always charged and maintained at a fully charged state. Is done.

The power storage system 100 further includes a control unit 103, a detection unit 104, a converter unit 105, a switching unit 106, a first power storage unit control unit 101a, a second power storage unit control unit 102a, a control power supply switching unit 107, and a clock 108.

The detection unit 104 detects the power system 1 for the vehicle, specifically, the voltage or power of the power line 4 shown in FIG. 1 and sends the detection result to the control unit 103. The detection unit 104 may include a voltmeter that detects the voltage of the power line 4, may include an ammeter that detects a current of the power line 4, and may include a voltmeter and an ammeter. The detection unit 104 may be controlled by the control unit 103 for detection operation.

The converter unit 105 is electrically connected to the vehicle power system 1, specifically to the power line 4. The converter unit 105 adjusts the DC power supplied from the power line 4 to a voltage suitable for being stored in the first power storage unit 101 or the second power storage unit 102 and sends it to the switching unit 106. Further, converter unit 105 adjusts the power of first power storage unit 101 or second power storage unit 102 to a voltage suitable for vehicular power system 1 by boost conversion or the like, and supplies the power to vehicular power system 1. Converter unit 105 constitutes a DC-DC converter that performs conversion between DC power. Converter unit 105 may be configured as an independent device or may be incorporated in the device as a circuit. Converter unit 105 is controlled by step-down conversion operation and step-up conversion operation by control unit 103.

The switching unit 106 is electrically connected to the converter unit 105, the first power storage unit 101, and the second power storage unit 102. Switching unit 106 selects and executes one of connecting converter unit 105 and first power storage unit 101 and connecting converter unit 105 and second power storage unit 102. The switching unit 106 sends an electrical signal to the control power supply switching unit 107 when the connection is switched. For example, the switching unit 106 sends an electrical signal to the control power supply switching unit 107 while the converter unit 105 and the second power storage unit 102 are connected. The switching unit 106 is controlled by the control unit 103 to perform a switching operation. The switching unit 106 may be configured as an independent device, or may be incorporated in the device as a circuit such as a switching relay circuit.

The first power storage unit control unit 101a and the second power storage unit control unit 102a are respectively in the state of the power storage unit such as the voltage, temperature, SOC, and the like in the first power storage unit 101 and the second power storage unit 102 and abnormal in the power storage unit. Monitor for occurrence of When the first power storage unit control unit 101a and the second power storage unit control unit 102a detect an abnormality in the first power storage unit 101 and the second power storage unit 102, respectively, the first power storage unit 101 and the second power storage unit 102 are charged and discharged. Control may be performed such as stopping or electrically disconnecting the first power storage unit 101 and the second power storage unit 102 from other devices. The first power storage unit control unit 101 a and the second power storage unit control unit 102 a may be configured to display the monitoring result and the control result on the display unit, respectively, or may be configured to send to the control unit 103. .

The first power storage unit control unit 101a and the second power storage unit control unit 102a may be provided integrally as part of the first power storage unit 101 and the second power storage unit 102, respectively, or may be provided separately. Each of the first power storage unit control unit 101a and the second power storage unit control unit 102a may be configured by independent electronic control units as in the configuration of the control unit 103 described later. It may be configured by a circuit centered on a microcomputer incorporated in the unit 102 or other device, or a circuit without a microcomputer. Or the 1st electrical storage part control part 101a and the 2nd electrical storage part control part 102a may be implement | achieved by running the software program suitable for each component.

The first power storage unit control unit 101 a and the second power storage unit control unit 102 a are supplied with power from the control power supply 10 outside the power storage system 100. The power supply 10 for control is a power supply by an electric power system different from the electric power system 1 for vehicles. The control power supply 10 supplies the power storage system 100 with, for example, DC power having a voltage of about 100V or AC power having a voltage of about 100 to 200V. The control power supply 10 may be a power supply by a commercial power system such as an electric power company, an uninterruptible power supply device provided at a place where the power storage system 100 is installed, a backup power supply dedicated to the power storage system 100, and the like. The power source may be a power storage device or a power generation device.

In addition, a DC-DC converter that controls the voltage of the DC power may be provided between the control power supply 10 and the first power storage unit control unit 101a and the second power storage unit control unit 102a. An AC-DC converter may be provided for converting into In this case, the DC-DC converter and the AC-DC converter between the control power supply 10 and the second power storage unit control unit 102a are arranged between the control power supply switching unit 107 and the second power storage unit control unit 102a. Also good. The DC-DC converter and the AC-DC converter may be configured as independent devices, or may be incorporated in the device as a circuit.

The control power supply opening / closing unit 107 selectively performs energization between the control power supply 10 and the second power storage unit control unit 102a and the interruption of the energization. The control power supply opening / closing unit 107 connects the control power supply 10 and the second power storage unit control unit 102a while receiving an electrical signal from the switching unit 106 (while the converter unit 105 and the second power storage unit 102 are connected). Connect electrically. In addition, when the control power supply switching unit 107 does not receive an electrical signal from the switching unit 106 (when the converter unit 105 and the second power storage unit 102 are not connected), the control power supply 10 and the second power storage unit control unit 102a. Disconnect the electrical connection with the. The control power supply opening / closing unit 107 may be controlled by the control unit 103 for energization and deenergization operations. The control power supply switching unit 107 may be configured by an independent device such as a switch or may be incorporated in the device as a part of a circuit.

The clock 108 measures the current date and time. The clock 108 sends the clocked date and time to the control unit 103. The clock 108 may have a function of notifying the control unit 103 or the like of the set date and time. The timepiece 108 may be controlled by the control unit 103 to measure time.

In the present embodiment, the control unit 103 controls operations of the detection unit 104, the converter unit 105, the switching unit 106, the clock 108, and the like. The control unit 103 may be configured to control the first power storage unit control unit 101a, the second power storage unit control unit 102a, the control power supply switching unit 107, and the like. The control unit 103 may be configured by an independent electronic control unit or a computer, and is configured by a circuit centered on a microcomputer incorporated in the converter unit 105 or the switching unit 106, or a circuit that does not have a microcomputer. May be. The control unit 103 is not configured by dedicated hardware as described above, and may be realized by executing a software program suitable for each component. In this case, the control unit 103 may include, for example, an arithmetic processing unit (not shown) and a storage unit (not shown) that stores a control program. Examples of the arithmetic processing unit include an MPU (Micro Processing Unit) and a CPU (Central Processing Unit). Examples of the storage unit include a memory. The control unit 103 may be configured by a single control unit that performs centralized control, or may be configured by a plurality of control units that perform distributed control in cooperation with each other.

Next, the operation of the power storage system 100 according to the embodiment will be described.

Referring to FIGS. 1 and 2, when the vehicle power system 1 such as the substation 2 is operating normally, the control unit 103 of the power storage system 100 includes a switching unit 106, a converter unit 105, and a first power storage unit. The unit 101 is electrically connected. At this time, converter unit 105 and second power storage unit 102 are not electrically connected. In the present embodiment, the vehicle power system 1 is operating normally means that the substation 2 is supplying power to the power line 4 at a predetermined voltage value and current value. On the other hand, when the vehicle power system 1 is not operating normally, that is, when the vehicle power system 1 is operating abnormally, power is applied to the power line 4 when the substation 2 is less than a predetermined voltage value or less than a predetermined current value due to a failure or the like. (For example, when substation 2 cannot supply power to power line 4 due to a power failure or the like).

In a state where converter unit 105 and first power storage unit 101 are electrically connected, surplus power of vehicle power system 1 is supplied to first power storage unit 101 via converter unit 105 and switching unit 106 and stored. The The surplus power of the vehicle power system 1 includes power supplied from the substation 2 to the power line 4 but not used by the train 3, and regenerative power of the train 3. At this time, converter unit 105 stores the surplus power in first power storage unit 101. In addition, converter unit 105 supplies the stored power of first power storage unit 101 to power line 4 when the power supplied from substation 2 to power line 4 is insufficient with respect to the power required by train 3. At this time, converter unit 105 adjusts the stored power of first power storage unit 101 by boosting or the like and supplies it to power line 4. Thus, the 1st electrical storage part 101 repeats charging / discharging frequently. For example, the first power storage unit 101 repeats charging and discharging with an SOC of about 15% to about 85%. In addition, the 2nd electrical storage part 102 is charged in the state close | similar to a full charge state previously, for example, has SOC near 100%.

The control unit 103 controls the operation of the converter unit 105 between the power supply operation from the vehicle power system 1 to the first power storage unit 101 and the power supply operation from the first power storage unit 101 to the vehicle power system 1. . Specifically, the control unit 103 determines the excess or deficiency of power in the power line 4 based on the current value, voltage value, power value, etc. of the vehicle power system 1, that is, the power line 4, acquired through the detection unit 104. The control unit 103 determines an operation to be performed by the converter unit 105 based on the determination result, and controls the operation of the converter unit 105.

When the switching unit 106 is electrically connecting the converter unit 105 and the first power storage unit 101, no electrical signal is sent from the switching unit 106 to the control power source switching unit 107. For this reason, the control power supply switching unit 107 cuts off the electrical connection between the second power storage unit control unit 102a and the control power supply 10. Thereby, the operation of the second power storage unit control unit 102a is stopped, and the stored power of the second power storage unit 102 is suppressed from being discharged to the second power storage unit control unit 102a. That is, when the second power storage unit control unit 102a and the second power storage unit 102 are electrically connected, the stored power of the second power storage unit 102 can be discharged to the second power storage unit control unit 102a. As described above, the second power storage unit 102 can keep the SOC high while the discharge amount is kept low while the operation of the second power storage unit control unit 102a is stopped.

When the vehicle power system 1 such as the substation 2 is not normally operated, that is, when the vehicle power system 1 is abnormally operated, the control unit 103 of the power storage system 100 includes the converter unit 105 and the second power storage unit. The unit 102 is electrically connected. At this time, electrical connection between converter unit 105 and first power storage unit 101 is interrupted. In a state where converter unit 105 and second power storage unit 102 are electrically connected, the stored power of second power storage unit 102 is supplied to power line 4 of vehicle power system 1. When the vehicle power system 1 is operating abnormally, the train 3 can be operated by using the power stored in the second power storage unit 102 having a high SOC. This enables safe operation management of the train 3 such that the train 3 is stopped at a desired place such as the station 5 without being stopped at an undesired place such as between the stations 5.

The control unit 103 obtains the electrical connection between the converter unit 105 and the second power storage unit 102 by the switching unit 106 via the detection unit 104. The current value, voltage value, power value, etc. of the vehicle power system 1 Determine based on Specifically, the control unit 103 electrically connects the converter unit 105 and the second power storage unit 102 when the current value, voltage value, power value, or the like acquired via the detection unit 104 falls below a predetermined threshold value. Decide on implementation. Alternatively, control unit 103 may receive a switching signal from the outside of power storage system 100 and perform electrical connection between converter unit 105 and second power storage unit 102 by switching unit 106. On the other hand, if the current value, voltage value, power value, etc. acquired via detection unit 104 are equal to or greater than a predetermined threshold, control unit 103 electrically connects converter unit 105 and first power storage unit 101 to switching unit 106. Connect to. Alternatively, the control unit 103 may receive a switching signal from the outside of the power storage system 100 and perform the electrical connection between the converter unit 105 and the first power storage unit 101 by the switching unit 106.

Further, the switching unit 106 transmits an electrical signal to the control power source switching unit 107 at the same time as the electrical connection between the converter unit 105 and the second power storage unit 102. Switching unit 106 continues to transmit the electric signal while electrically connecting converter unit 105 and second power storage unit 102. The control power supply switching unit 107 that has received the electrical signal electrically connects the second power storage unit control unit 102 a and the control power supply 10. Thereby, the second power storage unit control unit 102a starts monitoring and controlling the second power storage unit 102. Therefore, the electrical connection between the second power storage unit control unit 102a and the control power source 10 by the control power supply switching unit 107 is linked to the electrical connection between the converter unit 105 and the second power storage unit 102 by the switching unit 106. . That is, the start of energization of the vehicle power system 1 and the second power storage unit 102 and the start of operation of the second power storage unit control unit 102a are linked.

When the electrical connection between the converter unit 105 and the second power storage unit 102 by the switching unit 106 is released, the second power storage unit control unit 102a by the control power supply switching unit 107 and the control power supply unit 107 are interlocked with the release. The electrical connection with the power supply 10 is released. The operation of the control power supply switching unit 107 linked with the operation of the switching unit 106 may be performed by the control unit 103.

Further, the control unit 103 of the power storage system 100 charges the second power storage unit 102 so as to have a power storage amount equal to or higher than a predetermined SOC under a predetermined condition. For example, the predetermined SOC can be a value from about 85% to nearly 100%. Specifically, the control unit 103 charges the second power storage unit 102 periodically based on the date and time acquired from the clock 108, for example, at regular intervals. In addition, although the battery cell of the 2nd electrical storage part 102 has a low self-discharge rate, it self-discharges slightly over time. For example, in the present embodiment, the fixed period is 7 days, and the charging execution time of the second power storage unit 102 is also fixed. Further, for example, the charging time of the second power storage unit 102 is selected at a time when the amount of power consumption in the vehicle power system 1 is small. Specifically, the control unit 103 charges the second power storage unit 102 from 5:00 to 5:30 in the early morning before the operation of the train 3 or from 1:00 to 1:30 at midnight after the operation. Set as time. In this case, control unit 103 starts charging second power storage unit 102 at 5:00 in the early morning or at midnight. The charging execution time can be arbitrarily set. Further, the timing of charging the second power storage unit 102 (the above predetermined condition) is not limited periodically, and charging is performed when the voltage or SOC of the second power storage unit 102 becomes a predetermined value or less. The battery may be charged under any conditions.

When charging the second power storage unit 102, the control unit 103 switches the connection of the switching unit 106 to electrically connect the converter unit 105 and the second power storage unit 102. At this time, the second power storage unit control unit 102a also operates. During electrical connection between converter unit 105 and second power storage unit 102, control unit 103 controls converter unit 105 in the same manner as when vehicle power system 1 operates normally, and second power storage unit 102. To charge. Since it is before the operation of the train 3 or after the operation, the second power storage unit 102 is efficiently charged.

The control unit 103 detects that the SOC of the second power storage unit 102 acquired from the second power storage unit control unit 102a reaches the predetermined SOC, or 5:30 in the early morning when the time acquired from the clock 108 is a predetermined end time. Alternatively, the charging of the second power storage unit 102 is stopped at 1:30 midnight. That is, control unit 103 switches connection of switching unit 106 to electrically connect converter unit 105 and first power storage unit 101. Thereby, the SOC of the second power storage unit 102 is charged and maintained at or above a predetermined SOC.

Next, the process performed by the power storage system 100 according to the embodiment will be specifically described. FIG. 3 is a flowchart illustrating processing performed by the power storage system 100 of FIG.

As shown in FIG. 3, first, the switching unit 106 determines whether or not the substation 2 is operating normally (S101). When switching unit 106 determines that substation 2 is not operating normally (during abnormal operation of substation 2) (No in S101), switching unit 106 connects vehicular power system 1 and second power storage unit 102 (S102). ). When the switching unit 106 connects the second power storage unit 102 to the vehicle power system 1 (S102), the control power source switching unit 107 connects the second power storage unit control unit 102a and the control power source 10. (S103). As described above, the connection operation of the control power supply opening / closing unit 107 is interlocked with the connection operation of the second power storage unit 102 and the vehicle power system 1 by the switching unit 106.

In addition, when the switching unit 106 determines that the substation 2 is operating normally (during normal operation of the substation 2) (Yes in S101), the switching unit 106 determines whether or not a predetermined condition is satisfied (S104). When switching unit 106 determines that the predetermined condition is satisfied (Yes in S104), it connects vehicle power system 1 and second power storage unit 102 (S105), and sets second power storage unit 102 to a predetermined power storage amount. It is maintained at a predetermined charged amount by charging (S106).

Further, when determining that the predetermined condition is not satisfied (No in S104), the switching unit 106 connects the vehicle power system 1 and the first power storage unit 101 (S107). When the switching unit 106 connects the first power storage unit 101 to the vehicle power system 1 (S107), the control power source switching unit 107 shuts off the second power storage unit control unit 102a and the control power source 10. (S108). As described above, the shut-off operation of the control power supply opening / closing unit 107 is interlocked with the connection operation between the first power storage unit 101 and the vehicle power system 1 by the switching unit 106.

Thus, the description of the process performed by the power storage system 100 ends.

As described above, power storage system 100 according to the embodiment of the present invention includes first power storage unit 101, second power storage unit 102, first power storage unit 101, or second power storage unit 102 of power storage system 100. A switching unit 106 that is selectably connected to the outside, a second power storage unit control unit 102a that controls the second power storage unit 102 using the control power source 10 as a power source, a second power storage unit control unit 102a, and a control power source 10 And a control power supply opening / closing unit 107 for connecting or disconnecting. When the switching unit 106 connects the first power storage unit 101 to the outside of the power storage system 100, the control power supply opening / closing unit 107 shuts off the second power storage unit control unit 102a and the control power source 10, and the switching unit 106 When the second power storage unit 102 is connected to the outside of the power storage system 100, the second power storage unit control unit 102a and the control power supply 10 are connected.

In the above-described configuration, the second power storage unit control unit 102a is electrically connected to the second power storage unit 102 for control or the like, so that when the second power storage unit control unit 102a is operating, Discharge from unit 102 to second power storage unit control unit 102a may occur. The second power storage unit control unit 102a stops when the switching unit 106 connects the outside of the power storage system 100 and the first power storage unit 101, and the switching unit 106 connects the outside of the power storage system 100 and the second power storage unit. It operates when it is connected to 102. Therefore, the self-discharge of the second power storage unit 102 is suppressed when the second power storage unit control unit 102a is not used. In addition, the power storage system 100 including the first power storage unit 101 and the second power storage unit 102 can store the regenerative power of the train 3 and supply the stored power to the train 3. Furthermore, the power storage system 100 can stably supply power to the train 3 by using the second power storage unit 102 having a high power storage amount as an emergency power storage unit.

In the power storage system 100 according to the embodiment, the disconnecting operation between the second power storage unit control unit 102a and the control power source 10 by the control power source switching unit 107 is performed by the switching unit 106 between the first power storage unit 101 and the power storage system 100. Interlocks with external connection operations. In the above configuration, the self-discharge of the second power storage unit 102 immediately after the connection of the first power storage unit 101 and the outside of the power storage system 100 by the switching unit 106 is suppressed.

In the power storage system 100 according to the embodiment, the connection operation between the second power storage unit control unit 102a and the control power source 10 by the control power source switching unit 107 is performed between the second power storage unit 102 and the power storage system 100 by the switching unit 106. Interlocks with external connection operations. In the above-described configuration, the second power storage unit control unit 102a can be operated immediately after the switching unit 106 connects the second power storage unit 102 to the outside of the power storage system 100.

Furthermore, in the power storage system 100 according to the embodiment, the cutoff operation between the second power storage unit control unit 102a and the control power source 10 by the control power source switching unit 107 is the same as the first power storage unit 101 of the switching unit 106 and the power storage system. The connection operation between the second power storage unit control unit 102a and the control power source 10 by the control power source switching unit 107 is linked to the connection operation with the outside of the control unit 100, and the second power storage unit 102 of the switching unit 106 and the power storage system It works in conjunction with the external connection operation of 100. In the above-described configuration, the second power storage unit control unit 102 a operates only when the second power storage unit 102 is used by linking the operation of the control power supply switching unit 107 and the operation of the switching unit 106.

In the power storage system 100 according to the embodiment, the first power storage unit 101 has characteristics and high-rate characteristics that are more suitable for repeated charge / discharge than the second power storage unit 102, and the second power storage unit 102 It has characteristics of higher capacity (high energy density) than 101. In the above-described configuration, the second power storage unit 102 can suppress self-discharge when not in use. The first power storage unit 101 may be a normal power source connected to the outside of the normal power storage system 100, and the second power storage unit 102 may be an emergency power source not connected to the outside of the normal power storage system 100. it can. Such a configuration is suitable for the characteristics of the first power storage unit 101 and the second power storage unit 102.

In the power storage system 100 according to the embodiment, the switching unit 106 connects the outside of the power storage system 100 and the first power storage unit 101 when the substation 2 is operating normally, and powers when the substation 2 is operating abnormally. The outside of the storage system 100 is connected to the second power storage unit 102. In the above-described configuration, the power storage system 100 can use the second power storage unit 102 with high capacity and suppressed self-discharge as an emergency power supply that replaces the substation 2.

In the power storage system 100 according to the embodiment, the switching unit 106 connects the outside of the power storage system 100 and the second power storage unit 102 under a predetermined condition, and charges the second power storage unit 102 to a predetermined power storage amount. . In the above-described configuration, the power storage amount of the second power storage unit 102 can be maintained at a predetermined power storage amount. Therefore, sufficient power supply can be obtained from the second power storage unit 102 when the second power storage unit 102 is used.

In the power storage system 100 according to the embodiment, the second power storage unit 102 can also be used as a power source for peak cut that reduces power received from an electric power company at the time of peak power usage such as during commuting rush hours. This contributes to power saving measures and can reduce the electricity bill because the contracted power of the power company can be reduced. For example, the capacity of the second power storage unit 102 may be increased so that about 30% is used as a peak cut power source and about 70% is used as an emergency power source. Alternatively, instead of using the second power storage unit 102 as a power source for peak cut, a third power storage unit for peak cut may be newly added. In this case, when the voltage of the power line 4 rises due to the regenerative power generated by the train 3, the second power storage unit 102 or the third power storage unit may store the regenerative power.

In the power storage system 100 according to the embodiment, it is possible to suppress a decrease or increase in the voltage of the power line 4 (perform overhead line voltage compensation). For example, when a large amount of power is used, such as during commuting rush, power is supplied (discharged) from the first power storage unit 101 so that the voltage of the power line 4 does not drop too much, so that the voltage of the power line 4 becomes equal to or higher than a certain voltage. To control. In addition, when the amount of power used is low, such as during a quiet period, power is stored (charged) in the first power storage unit 101 so that the voltage of the power line 4 does not increase excessively, so that the voltage of the power line 4 becomes a certain voltage or less. Control. In addition, the voltage of the power line 4 can be controlled to be small by charging / discharging the first power storage unit 101.

[Other variations]
The power storage system 100 according to the embodiment of the present invention has been described above, but the present invention is not limited to the embodiment. That is, the embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The technology in the present disclosure can also be applied to a modified example of the embodiment in which modifications, replacements, additions, omissions, and the like are appropriately performed or other embodiments. Unless it deviates from the gist of the present disclosure, various modifications conceived by those skilled in the art have been made in this embodiment, and forms constructed by combining components in different embodiments are also within the scope of one or more aspects. May be included. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

In the power storage system 100 according to the embodiment, the cutoff operation of the control power supply switching unit 107 is linked to the connection operation between the first power storage unit 101 and the vehicle power system 1, but the cutoff operation and the connection The operation is not limited to being completely interlocked, and there may be a slight time difference. In addition, the connection operation of the control power supply opening / closing unit 107 is linked to the connection operation of the second power storage unit 102 and the vehicle power system 1, but this is also completely linked in the same manner. It is not limited and there may be some time difference.

In the power storage system 100 according to the embodiment, the first power storage unit 101 has characteristics and high-rate characteristics that are more suitable for repeated charging and discharging than the second power storage unit 102, and the second power storage unit 102 It has a higher capacity characteristic than 101. However, as the first power storage unit 101 and the second power storage unit 102, those having various characteristics that do not satisfy the above can be selected.

In the power storage system 100 according to the embodiment, the converter unit 105 is a DC-DC converter, but may be an AC-DC converter. That is, when AC power is supplied from the substation 2 to the power line 4 and the train 3 is driven by AC power, the converter unit 105 is preferably an AC-DC converter. Alternatively, when DC power is supplied from the substation 2 to the power line 4 and the first power storage unit 101 and the second power storage unit 102 can handle the voltage of the DC power, the converter unit 105 is provided. It does not have to be done.

In the power storage system 100 according to the embodiment, the control power supply 10 is provided. However, when another power supply can be substituted, the control power supply 10 may not be provided. For example, instead of the control power supply 10, control power can be supplied from the first power storage unit 101 or the second power storage unit 102.

In the power storage system 100 according to the embodiment, the control unit 103 electrically connects the vehicular power system 1 and the second power storage unit 102 when the substation 2 is abnormally operated, but is not limited thereto. It is not something. The control unit 103 controls the vehicle power system 1 from the first power storage unit 101 when an abnormality occurs in the first power storage unit 101, or when the power storage amount such as the SOC of the first power storage unit 101 decreases below a predetermined value. If a sufficient amount of power supply to the vehicle cannot be secured, the vehicle power system 1 and the second power storage unit 102 may be electrically connected.

In the power storage system 100 according to the embodiment, the accumulated power of the first power storage unit 101 and the second power storage unit 102 is supplied to the vehicle power system 1, but is not limited to this, and the station 5 Or other elements.

Although the power storage system 100 according to the embodiment includes the two power storage units including the first power storage unit 101 and the second power storage unit 102, the power storage system 100 may include three or more power storage units.

The power storage system 100 according to the embodiment has been applied to an electric power system of an electric railway, but is not limited thereto. The power storage system generates power for the power system of automobiles, the power system of traffic that obtains power for powering from power lines such as overhead lines such as trolley buses, solar power generation systems such as buildings, and exhaust heat power generation systems. The present invention may be applied to a system that consumes power.

In the power storage system 100 according to the embodiment, the secondary battery constituting the first power storage unit 101 and the second power storage unit 102 is a lithium ion secondary battery, but is not limited to this, and nickel A secondary battery such as a hydrogen battery, a lead storage battery, a lithium ion polymer secondary battery, a nickel cadmium storage battery, a nickel iron storage battery, a nickel zinc storage battery, a silver zinc oxide storage battery, a flywheel battery, or a large capacity capacitor may be used.

The present invention can be applied to a power storage system that has power in and out.

1 Vehicle power system 2 Substation (Vehicle power supply)
3 Train (vehicle)
DESCRIPTION OF SYMBOLS 10 Power supply for control 100 Power storage system 101 1st electrical storage part 102 2nd electrical storage part 102a 2nd electrical storage part control part 106 Switching part 107 Control power supply opening / closing part

Claims

A power storage system,
A first power storage unit;
A second power storage unit;
A switching unit for selectively connecting the first power storage unit or the second power storage unit to the outside of the power storage system;
A second power storage unit control unit that controls the second power storage unit using a control power source as a power source;
A control power supply opening and closing unit for connecting or disconnecting the second power storage unit control unit and the control power supply,
The control power supply switching unit is
When the switching unit connects the first power storage unit to the outside of the power storage system, the second power storage unit control unit and the control power supply are shut off,
A power storage system that connects the second power storage unit control unit and the control power source when the switching unit connects the second power storage unit to the outside of the power storage system.
The power storage system according to claim 1, wherein the shut-off operation of the control power supply opening / closing unit is interlocked with a connection operation between the first power storage unit and the outside of the power storage system by the switching unit.
The power storage system according to claim 1, wherein the connection operation of the control power supply opening / closing unit is interlocked with a connection operation between the second power storage unit and the outside of the power storage system by the switching unit.
4. The first power storage unit has characteristics suitable for repeated charging and discharging than the second power storage unit, and the second power storage unit has higher capacity characteristics than the first power storage unit. The power storage system according to any one of the above.
The power storage system according to any one of claims 1 to 4, wherein the first power storage unit has a higher rate characteristic than the second power storage unit.
The switching unit is configured to selectably connect the first power storage unit or the second power storage unit to a vehicle that generates regenerative power outside the power storage system and a vehicle power source that supplies power to the vehicle. The power storage system according to any one of claims 1 to 5.
The switching unit connects the outside of the power storage system and the first power storage unit during normal operation of the vehicle power supply,
The power storage system according to claim 6, wherein when the vehicle power supply is abnormally operated, the outside of the power storage system is connected to the second power storage unit.
The switching unit connects the outside of the power storage system and the second power storage unit under a predetermined condition, and charges the second power storage unit to a predetermined power storage amount. The power storage system described.