JP2015220873A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device that can drive a secondary battery with power from the external.SOLUTION: A power storage device 1 has an AC input terminal 2 for inputting AC power from the external, a secondary battery 4, a converter 3 for converting AC power input from the AC input terminal 2 to DC power and outputting the DC power to the secondary battery 4, and converting DC power output from the secondary battery 4 to AC power, an AC output terminal 9 for outputting the AC power converted by the converter 3, a battery managing unit for achieving information representing the state of the secondary battery 4 and controlling charging/discharging of the secondary battery 4, a first power supplier 5a for converting AC power input from the AC input terminal 2 and supplying the power to the converter 3, and a second power supplier 5b for converting AC power input from the AC input terminal 2 and supplying the power to the battery managing unit 16.

Description

  The present invention relates to a technology of a power storage device using a storage battery.

  In recent years, various power storage systems using storage batteries have been proposed. For example, Patent Document 1 below discloses an uninterruptible power supply that converts a DC voltage from a power storage means such as a lead-acid battery into an AC voltage and outputs it to a load when the AC power supply is in an abnormal state such as a power failure. ing.

  In addition, the power storage system may be used in a form that is connected to a power system and supplies power to a load according to control by the energy management system (for example, see Patent Document 2 below). As a result, it is possible to efficiently supply power to the load in accordance with the power supply / demand balance of the power system, the load usage status, and the like. A storage battery in an uninterruptible power supply device or a power storage system that operates in cooperation with the system as described above is required to supply power to a load connected to an AC power source such as a power system.

JP 2011-45153 A JP 2013-233300 A

  Electric power for driving the storage battery control circuit and the inverter circuit can be supplied from the storage battery. Here, if the power for driving the storage battery control circuit and the inverter circuit can be supplied by, for example, AC power input from the outside of the power system or the like, more power is supplied from the storage battery to the load. Can do. In the prior art, there is no mechanism for efficiently driving the storage battery using electric power from the outside. Therefore, the present application discloses a power storage device that can efficiently drive a storage battery using external power.

  The power storage device according to one embodiment of the present invention includes an AC input terminal for inputting AC power from the outside, a storage battery, and AC power input from the AC input terminal into DC power to the storage battery. Outputs and converts the DC power output from the storage battery into AC power, the AC output terminal for outputting the AC power converted by the converter, and information indicating the state of the storage battery A battery management unit that controls charging / discharging of the storage battery, a first power supply unit that converts the AC power input from the AC input terminal and supplies power to the conversion unit, and the AC input terminal. A second power supply unit that converts the alternating current power input from the power source and supplies power to the battery management unit.

  According to the present disclosure, a power storage device that efficiently drives a storage battery using external power can be realized.

FIG. 1 is a functional block diagram illustrating a configuration example of the power storage device. FIG. 2 is a functional block diagram illustrating a detailed configuration example of the power storage device. FIG. 3 is a diagram illustrating a circuit configuration example of the inverter in FIG.

  The power storage device according to one embodiment of the present invention includes an AC input terminal for inputting AC power from the outside, a storage battery, and AC power input from the AC input terminal into DC power to the storage battery. Outputs and converts the DC power output from the storage battery into AC power, the AC output terminal for outputting the AC power converted by the converter, and information indicating the state of the storage battery A battery management unit that controls charging / discharging of the storage battery, a first power supply unit that converts the AC power input from the AC input terminal and supplies power to the conversion unit, and the AC input terminal. A second power supply unit that converts the alternating-current power input from and supplies the alternating-current power to the battery management unit.

  According to the said structure 1, the alternating current power input from an alternating current input terminal is each converted by the 1st power supply part and the 2nd power supply part, and is separately supplied to a conversion part and a battery management part. As described above, by separately providing the first power supply unit that supplies power to the conversion unit and the second power supply unit that supplies power to the battery management unit, power is supplied to each of the conversion unit and the battery management unit. The route can be divided. Therefore, interference between the conversion unit and the battery management unit is suppressed, and efficient storage battery driving becomes possible.

  The said structure WHEREIN: The said conversion part can connect between the said AC input terminal and the said storage battery using a transformer-less converter, without insulation. Thereby, since a conversion part can be comprised without using a transformer, an electrical storage apparatus can be reduced in size. Moreover, since the power supply unit of the conversion unit and the power supply unit of the battery management unit are provided separately, noise caused by the conversion unit not insulated from the AC input terminal to the battery management unit The influence can be further suppressed.

  The said structure WHEREIN: Each of the said 1st power supply part and the said 2nd power supply part can have an insulation type converter. Thereby, interference with a conversion part and a battery management part can be decreased more.

  The power storage device may further include at least one battery pack including a plurality of the storage batteries, and a battery monitoring unit that is provided for each of the battery packs and monitors a state of the storage battery included in the battery pack. The battery monitoring unit is connected to the AC input terminal without being insulated, and the battery management unit acquires information indicating the state of the storage battery from the battery monitoring unit and controls charging / discharging of the storage battery. be able to. Thereby, even in the configuration using a plurality of storage batteries, interference between the conversion unit and the battery management unit is suppressed, and efficient driving of the storage battery becomes possible.

  The power storage device transmits data indicating the state of the storage battery to the outside and, based on the control data, a communication unit that receives control data generated based on the data indicating the state of the storage battery from the outside, A control unit that controls the operation of the storage battery, a third power supply unit that converts the AC power input from the AC input terminal and supplies power to the control unit, and is input from the AC power terminal And a fourth power supply unit that converts the AC power and supplies power to the communication unit. Thereby, the noise by interference between a conversion part, a battery management part, a communication part, and a control part can be reduced.

  The storage battery may be a lithium ion storage battery. This makes it possible to efficiently execute control based on the battery state such as the voltage or temperature of the lithium ion storage battery. In particular, it is important to manage the voltage, current, temperature, etc. of each battery cell in order to handle lithium ion batteries safely. For this reason, when using a lithium ion storage battery, it is preferable to mount the mechanism which detects the said voltage, electric current, temperature, etc., and controls operation | movement of a lithium ion storage battery based on this information in a storage battery. It is also important from the viewpoint of the performance of the power storage device to efficiently drive a control circuit for that purpose. By combining the power storage device disclosed in the present application with this lithium ion storage battery, a power storage device having both efficiency and safety can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated. In addition, in order to make the explanation easy to understand, in the drawings referred to below, the configuration is shown in a simplified or schematic manner, or some components are omitted. Further, the dimensional ratio between the constituent members shown in each drawing does not necessarily indicate an actual dimensional ratio.

(Configuration example of power storage device)
FIG. 1 is a functional block diagram illustrating a configuration example of the power storage device according to the present embodiment. The power storage device 1 illustrated in FIG. 1 includes an AC input terminal 2, a conversion unit 3, a lithium ion storage battery 4, a monitoring unit 6, a battery management unit 16, a communication unit 7, a control unit 8, and an AC output terminal 9. The AC input terminal 2 is a terminal that receives an input of AC power from the outside. The AC input terminal 2 is connected to a power system, for example. In this case, AC power from the system is input to the AC input terminal 2.

  The conversion unit 3 converts AC power input from the AC input terminal 2 into DC power and outputs the DC power to the storage battery 4. Moreover, the conversion part 3 converts the direct-current power output from the storage battery 4 into alternating current power. The conversion part 3 can be comprised using an inverter, for example. The configuration of the conversion unit 3 is not limited to a specific one. For example, the conversion unit 3 can be configured by a combination of a rectifier that converts alternating current to direct current and an inverter that converts direct current to alternating current, a bidirectional inverter, or the like. The AC power converted by the conversion unit 3 is supplied from the AC output terminal 9 to the load 20. For example, the AC output terminal 9 can be an outlet to which the load 20 can be connected. In addition, the form of the alternating current input terminal 2 and the alternating current output terminal 9 is not restricted to a specific thing.

  As the storage battery 4, a lithium ion storage battery, a lead storage battery, a nickel / cadmium storage battery, a nickel / hydrogen storage battery, and other secondary batteries capable of storing energy can be used. The storage battery 4 may be a combination of a plurality of batteries. The storage battery 4 is charged with DC power from the conversion unit 3 in accordance with control from the control unit 8. Moreover, the storage battery 4 outputs the stored energy to the conversion unit 3 as DC power.

  The battery management unit 16 acquires data indicating the state of the storage battery 4 such as temperature, current, voltage, and remaining amount, and controls the charge / discharge operation of the storage battery 4 based on the acquired data. The battery management part 16 can acquire the data which show the state of the storage battery 4 from the battery monitoring part which detects the electric current, voltage, temperature, etc. of the storage battery 4 so that it may mention later. Alternatively, the battery management unit 16 may have a function of detecting the current, voltage, temperature, or the like of the storage battery 4.

  The power supply unit 5 converts characteristics such as the voltage of the AC power input from the AC input terminal into predetermined characteristics and supplies the converted characteristics to each unit of the power storage device 1. In the example illustrated in FIG. 1, the power supply unit 5 includes a first power supply unit 5 a that supplies power to the conversion unit 3 and a second power supply unit 5 b that supplies power to the battery management unit 16.

  The first power supply unit 5 a converts AC power input from the AC input terminal 2 into power suitable for driving the conversion unit 3 and supplies the converted power to the conversion unit 3. For example, when the conversion unit 3 includes an inverter, the first power supply unit 5 a generates a voltage for driving the inverter from the AC power input from the AC input terminal 2.

  The second power supply unit 5 b converts the AC power input from the AC input terminal 2 into power suitable for driving the battery management unit 16 and supplies the power to the battery management unit 16. In the example illustrated in FIG. 1, the second power supply unit 5 b is a power supply unit dedicated to the battery management unit 16 that supplies power only to the battery management unit 16. That is, the battery management unit 16 is configured to have a dedicated power source using power input from the AC input terminal.

  As described above, the configuration in which the battery management unit 16 has the dedicated power source can make the battery management unit 16 less susceptible to noise. In the present example, the conversion unit 3 and the battery management unit 16 are provided separately by providing the first power supply unit 5a and the second power supply unit 5b that supply power to the conversion unit 3 and the battery management unit 16, respectively. The noise signal is less likely to propagate through the power supply unit 5. For example, a change in the ground on the primary side to which the AC input terminal 2 is connected and a change in the ground of the load 20 to which the AC output terminal 9 is connected are transmitted to the battery management unit 16 through the conversion unit 3 and the power supply unit 5. It becomes difficult.

  Note that the voltage converter of the first power supply unit 5a and the voltage converter of the second power supply unit 5b can both be an insulation type converter using a transformer. Thereby, between the 1st electric power supply part 5a and the 2nd electric power supply part 5b can be insulated. In this case, the noise signal is more difficult to propagate between the conversion unit 3 and the battery management unit 16.

(Detailed configuration example of power storage device)
FIG. 2 is a functional block diagram illustrating a detailed configuration example of the power storage device. The power storage device 1 shown in FIG. 2 includes an AC input terminal 2, a conversion unit 3, a lithium ion storage battery 4, a monitoring unit 6, and a battery management unit 16, battery packs 40a and 40b, a communication unit 7, a control unit 8, and an AC output. A terminal 9 is provided.

  The converter 3 converts AC power input from the AC input terminal 2 into DC power and outputs the DC power to the lithium ion storage battery 4. Moreover, the conversion part 3 converts the direct current power output from the lithium ion storage battery 4 into alternating current power. The AC power converted by the conversion unit 3 is output from the AC output terminal 9. In the example illustrated in FIG. 2, the conversion unit 3 is configured by a non-insulated voltage converter that connects the AC input terminal 2 and the lithium ion storage battery 4 without insulation.

  As a configuration of the storage battery, a plurality of cells of the lithium ion storage battery 4 can be combined to form the battery packs 40a and 40b. In this example, a plurality of battery packs are provided. Each battery pack 40a, 40b is provided with a monitoring unit 6. The monitoring unit 6 monitors the state of the lithium ion storage battery 4 included in the battery packs 40a and 40b. The monitoring unit 6 detects the state of the lithium ion storage battery 4 such as temperature, current, voltage, and remaining amount, for example. A signal or data indicating the detected state of the lithium ion storage battery 4 is transmitted to the battery management unit 16. The battery management unit 16 acquires information indicating the state of the lithium ion storage battery 4 from the monitoring unit 6 and controls charging / discharging of the lithium ion storage battery 4 based on this information.

  The monitoring unit 6 and the battery management unit 16 are connected to the AC input terminal 2 without being insulated. Therefore, the monitoring unit 6 and the battery management unit 16 operate on a non-insulating unit with respect to the AC input terminal 2, that is, a primary side to which AC power is input. Therefore, the monitoring unit 6 monitors the battery voltage, battery current, and battery temperature of the lithium ion storage battery 4. The monitoring unit 6 may include a switch (relay 61) that disconnects the conversion unit 3 and the lithium ion storage battery 4 when an abnormality of the lithium ion storage battery 4 is detected.

  Further, the battery management unit 16 can receive data indicating the state of the lithium ion storage battery 4 from the monitoring unit 6 periodically. Data indicating the state of the lithium ion storage battery 4 received by the battery management unit 16 is transmitted to the outside through the control unit 8 and the communication unit 7, for example. In this case, the communication unit 7 can receive control data generated based on data indicating the state of the lithium ion storage battery 4 from the outside. The control unit 8 controls the operation of the lithium ion storage battery 4 based on the control data. Thereby, the state of the lithium ion storage battery 4 can be remotely monitored outside the power storage device 1. Moreover, the power storage device 1 can be remotely controlled from the outside by transmitting control data from the outside.

  In the example illustrated in FIG. 2, the power storage device 1 includes a frame 22 as a housing. The conversion unit 3, the battery packs 40 a and 40 b, the power supply unit 5, the battery management unit 16, the communication unit 7, and the control unit 8 are arranged in the frame 22.

  The conversion unit 3 includes a transformerless inverter 32 and a transformerless DC / DC converter 31. The inverter 32 is connected to the AC input terminal 2, the AC output terminal 9, and the DC / DC converter 31. The inverter 32 converts AC power input from the AC input terminal 2 into DC and outputs the DC power to the DC / DC converter 31. The inverter 32 converts the DC power input from the DC / DC converter 31 into AC and outputs the AC power from the AC output terminal 9.

  Although not shown in FIG. 2, an AC relay may be disposed between the AC input terminal 2 and the inverter 32. This AC relay controls ON / OFF of the connection between the AC input terminal 2 and the conversion unit 3. Thereby, the electrical storage apparatus 1 can be operated as an uninterruptible power supply (UPS). For example, in the external power supply mode in which AC power of the power system input from the AC input terminal 2 is supplied to the load 20, the AC relay is turned ON and the AC input terminal 2 and the conversion unit 3 are connected. In the battery power supply mode in which power supplied from the storage battery 4 is supplied to the load 20, the AC relay can be turned off to disconnect the connection between the AC input terminal 2 and the conversion unit 3.

  The DC / DC converter 31 changes the voltage of the DC power output from the inverter 32 to a voltage suitable for the lithium ion storage battery 4 and outputs it to the lithium ion storage battery 4. In addition, the DC / DC converter 31 changes the voltage of the DC power output from the lithium ion storage battery 4 and outputs it to the inverter 32.

  The converter 3 can be reduced in size by using the transformerless inverter 32 and the DC / DC converter 31 in this way. The circuit configurations of the transformerless inverter 32 and the DC / DC converter 31 are not limited to specific ones. For example, a transformerless inverter can be configured using a full-bridge semiconductor switching element.

  FIG. 3 is a diagram showing an example of a circuit configuration of the inverter 32 of FIG. In the circuit example shown in FIG. 3, a transformerless full-bridge inverter is used. Specifically, a full-bridge inverter circuit 321 is disposed between the AC input terminals 2 a and 2 b and the terminals 4 a and 4 b of the lithium ion storage battery 4. Switching elements S2 and S3 are provided between the AC input terminals 2a and 2b and the inverter circuit 321.

  The inverter circuit 321 includes first switching element groups S4 and S5 connected in series, and second switching element groups S6 and S7 connected in series as well. The first switching element groups S4 and S5 and the second switching element groups S6 and S7 are all connected in parallel to the lithium ion storage battery 4. A node between the switching elements S4 and S5 is connected to a node on a line connecting the AC input terminal 2b and the AC output terminal 9b. Similarly, a node between the switching S6 and S7 is connected to a line connecting the AC input terminal 2a and the AC output terminal 9a via the coil L1. For example, semiconductor switching elements such as IGBTs or MOSFETs can be used as the switching elements S4 to S7.

  A capacitor C2 is connected between a node on the line connecting the AC input terminal 2a and the AC output terminal 9a and a node on the line connecting the AC input terminal 2b and the AC output terminal 9b. That is, the coil L1 is connected in series and the capacitor C2 is connected in parallel between the inverter circuit 321 and the AC output terminals 9a and 9b.

  The inverter 32 having the circuit configuration shown in FIG. 3 includes a coil L1, a capacitor C2, and switching elements S1 to S7, but does not include a transformer. In the circuit of FIG. 3, for example, a transformer may be provided instead of the coil L1. In this case, for example, if a 50 Hz transformer is provided, the circuit becomes large. Therefore, as shown in FIG. 3, by providing the coil L1, it can be formed much smaller than when a transformer is provided. As a result, the inverter 32 can be reduced in size, and as a result, the entire power storage device 1 can be reduced in size. In the configuration shown in FIG. 3, the voltage of the AC input terminals 2 a and 2 b is applied to the lithium ion storage battery 4. Therefore, it is preferable that the basic insulation is carried out between the lithium ion storage battery 4 and the case which accommodates this.

  In the circuit shown in FIG. 3, by controlling the switching of the switching elements S <b> 4 to S <b> 7, the inverter circuit 321 receives the AC voltage between the AC input terminals 2 a and 2 b as input and enters between the terminals 4 a and 4 b of the lithium ion storage battery 4. It can be operated as a forward conversion circuit that outputs a DC voltage. Alternatively, by controlling the switching of the switching elements S4 to S7, the inverter circuit 321 receives the DC voltage between the terminals 4a and 4b of the lithium ion storage battery 4 and outputs the AC voltage to the AC output terminals 9a and 9b. It can also be operated as an inverse conversion circuit. In this way, the control mode of the switching elements S4 to S7 can be switched. Electric power for controlling the switching of the switching elements S4 to S7 can be supplied from the power supply unit 5.

  For example, when the switching elements S2 and S3 are ON, the inverter circuit 321 can be operated as a forward conversion circuit. In this case, the inverter 32 converts AC power input from the AC input terminals 2a and 2b into DC power, charges the lithium ion storage battery 4, and outputs AC power to the AC output terminals 9a and 9b. it can. Further, when the switching elements S2 and S3 are OFF, the inverter circuit 321 can be operated as an inverse conversion circuit. In this case, the inverter 32 can convert the direct-current power output by the discharge of the lithium ion storage battery 4 into alternating current and output it from the alternating-current output terminals 9a and 9b.

  Referring to FIG. 2 again, the DC / DC converter 31 is connected to the lithium ion storage batteries 4 of the plurality of battery packs 40a and 40b. The battery packs 40a and 40b include a cell group of lithium ion storage batteries 4 connected in series and a case 21 that houses the cell group. The case 21 and the cell group of the lithium ion storage battery 4 are fundamentally insulated. Case 21 is grounded to the ground (frame ground) of frame 22 of power storage device 1.

  The monitoring unit 6 is provided in each of the plurality of battery packs 40a and 40b. Note that the monitoring unit 6 may be provided inside the case 21 of the battery packs 40 a and 40 b or outside the case 21. The monitoring unit 6 measures the voltage of each of the plurality of lithium ion storage batteries 4 connected in series. The monitoring unit 6 measures the current and temperature of the lithium ion storage battery 4.

  The monitoring unit 6 is configured to stop the output of the lithium ion storage battery 4 when detecting that any of the voltage, current, and temperature of the lithium ion storage battery 4 is out of the preset normal range. For example, when the monitoring unit 6 detects any of overcurrent, voltage drop, or overheating, the monitoring unit 6 can open the relay 61 that connects the lithium ion storage battery 4 and an external circuit at high speed. Thus, safety can be improved by adopting a configuration in which the monitoring unit 6 provided in each of the battery packs 40a and 40b immediately disconnects the lithium ion storage battery 4 from the external system when an abnormality is detected. In particular, in the configuration in which the lithium ion storage battery 4 is non-insulated with respect to the primary side, the effect of contributing to the safety due to the detection of the abnormality by the monitoring unit 6 and the separation at the time of the abnormality appears significantly.

  The configuration of the monitoring unit 6 is not limited to the above. For example, other necessary configurations can be added. For example, a regulator for supplying a voltage suitable for the monitoring unit 6 or an AD converter that converts the detected current into a digital signal may be provided.

  Data indicating the state of the lithium ion storage battery 4 such as current, voltage, and temperature detected by the battery packs 40 a and 40 b is transmitted to the battery management unit 16. The battery management unit 16 and the monitoring unit 6 can communicate with each other with a differential signal. For example, RS-485 can be used for this differential signal communication.

  In the configuration shown in FIG. 2, the case 21 of the battery packs 40 a and 40 b is grounded to the frame 22 of the power storage device 1, that is, the frame ground. On the other hand, since the monitoring unit 6 and the battery management unit 16 are connected to the AC input terminal 2 and the AC output terminal 9 in a non-insulated manner, the ground level is the primary ground level. The ground level on the primary side may change corresponding to, for example, voltage fluctuations in the system connected to the AC input terminal 2. On the other hand, the frame ground is often constant. Therefore, the potential difference between the ground of the monitoring unit 6 and the battery management unit 16 and the frame ground varies, and this is likely to be a noise source. As in the example shown in FIG. 2, for example, the influence of noise due to the difference in ground level as described above can be obtained by using a differential system that is resistant to noise for communication between the monitoring unit 6 and the battery management unit 16. Can be suppressed.

  The battery management unit 16 is connected to the monitoring units 6 of the plurality of battery packs 40a and 40b via an insulating communication driver 16a. Thus, by using an insulation type device for the interface with the monitoring unit 6 in the battery management unit 16, the influence of noise can be suppressed. The insulating communication driver 16a can be formed by using an insulating signal transmission element that transmits only a signal between the input terminal and the output terminal to electrically insulate. An insulated signal transmission element is an element having both functions of electrical insulation and signal coupling between input and output. Such an element includes an element configured to transmit a signal using light, a magnetic field, or an electric field. For example, a photocoupler element, a magnetic coupler element, or a capacitively coupled isolator that transmits a signal using an electric field can be used as the insulating signal transmission element.

  The battery management unit 16 and the control unit 8 are connected via a photocoupler 9 which is an example of an insulating signal transmission element. Thereby, the battery management unit 16 and the control unit 8 can be insulated.

  In the power storage device 1 illustrated in FIG. 2, the power supply unit 5 is connected to the AC input terminal 2 and each unit of the power storage device 1, that is, the conversion unit 3, the battery management unit 16, and the control unit 8. The power supply unit 5 converts the AC power input from the AC input terminal 2 into a voltage suitable for the operation of each unit and outputs the voltage. The power supply unit 5 includes a third power supply unit 5c and a fourth power supply unit 5d in addition to the first power supply unit 5a and the second power supply unit 5b described above. The third power supply unit 5 c converts AC power input from the AC input terminal 2 and supplies power to the control unit 8. The fourth power supply unit 5 d converts the AC power input from the AC input terminal 2 and supplies the communication unit 8 with power.

  The first power supply unit 5a, the second power supply unit 5b, the third power supply unit 5c, and the fourth power supply unit 5d are all in parallel with the transformer 50, the diode 51 connected in series to the transformer 50, and the transformer 50. It has a capacitor 52 connected. These perform voltage conversion and rectification according to each power supply destination. The four transformers 50 in the first power supply unit 5a, the second power supply unit 5b, the third power supply unit 5c, and the fourth power supply unit 5d are connected in series with each other. These four transformers 50 are connected in parallel to the line between the AC input terminal 2 and the conversion unit 3. An AC / DC converter 54 is further connected to these four transformers 50.

  The transformer 50 of the first power supply unit 5a can be connected to a drive circuit (not shown) of the inverter 32 of the conversion unit 3, for example. The transformer 50 of the second power supply unit 5b is connected to the battery management unit 16 via a 5V regulator 53b. As a result, 5V power is supplied to the battery management unit 16. The transformer 50 of the third power supply unit 5c is connected to the control unit 8 via the regulator 53c. The transformer 50 of the fourth power supply unit 5d is connected to the communication unit 7 via the regulator 53d.

  In the configuration shown in FIG. 2, the conversion unit 3, the battery management unit 16, the control unit 8, and the communication unit 7 are each connected to the power supply unit 5 via different transformers 50. That is, the conversion unit 3, the battery management unit 16, the control unit 8, and the communication unit 7 are configured to receive power supply from the power supply unit 5 via separate transformers 50. Therefore, the grounds of the conversion unit 3, the battery management unit 16, the control unit 8, and the communication unit 7 can be separated from each other. For example, noise due to a change in ground level of the conversion unit 3 connected to the AC input terminal 2 is difficult to be transmitted to the battery management unit 16. As a result, it is possible to suppress noise transmission through the power supply path while reducing the size by making the conversion unit 3 non-insulating. In addition, the power consumed inside the power storage device 1 can be supplied from the outside without using the power of the lithium ion storage battery 4. Therefore, more power can be supplied from the lithium ion storage battery 4 to the load 20.

  In addition, the structure of the electric power supply path | route by the electric power supply part 5 is not restricted to the example shown in FIG. For example, at least two of the first to fourth power supply units 5a to 5d may share the transformer 50. In the above example, the transformer 50 is provided in each of the first to fourth power supply units 5a to 5d. The circuit for supplying each power is not limited to the configuration using the transformer 50, but may be configured using other circuits that generate desired power.

  The power supply unit 5 drives the conversion unit 3, the battery monitoring unit 16, the communication unit 7, and the control unit 8 when the input of AC power from the AC input terminal 2 is stopped, reduced, or increased. The power source may be switched to the lithium ion storage battery 4. For example, the power supply unit 5 can be configured to use the power input from the AC input terminal 2 and the power supplied from the lithium ion storage battery 4 in combination or switch as power sources of the respective units.

  In the configuration shown in FIG. 2, the configuration of the substrate on which each unit is mounted is not particularly limited. As an example, the conversion unit 3, the battery management unit 16, the control unit 8, and the communication unit 7 are formed on separate substrates. be able to. In this case, the battery supply unit 5 can be formed on the same substrate as the conversion unit 3. The power supply unit 5 also supplies power to a driver chip that realizes a communication interface between the battery management unit 16 and the control unit 8 and a driver chip that implements a communication interface between the control unit 8 and the communication unit 7. can do. For example, RS-232C can be used as these communication interfaces.

  In addition, a circuit can be added to the configuration shown in FIG. 2 as necessary. For example, a diode bridge and a capacitor can be disposed between the AC input terminal 2 and the inverter 32.

(Application example to uninterruptible power supply)
The power storage device 1 shown in FIG. 1 and FIG. 2 receives, as an example, the function of an uninterruptible power supply that receives AC power supplied from the system power and stores the power and supplies power of a certain standard to the load 20. Can have.

  The power storage device 1 has an external power supply mode in which AC power input from the AC input terminal 2 is supplied to the load 20 and AC power obtained by the converter 3 converting DC power using the storage battery 4 as power. A switching unit that switches between battery power supply modes for supplying the power to the load 20 may be provided. For example, when the switching unit detects a decrease or stop of AC power from the AC input terminal 2 or an increase in AC power exceeding a predetermined value, the switching unit disconnects the AC input terminal 2 and the load 20, The above modes can be switched. In the external power supply mode, AC power input from the AC input terminal 2 can be supplied to the load 20 as AC without being converted to DC. Alternatively, in the external power supply mode, AC power can be converted to DC, the DC power can be converted to AC power that satisfies a predetermined condition, and supplied to the load 20.

  The operation method as the uninterruptible power supply is not limited to a specific one. For example, when AC power is normally supplied from the AC input terminal 2, the AC power from the AC input terminal 2 is supplied to the load 20, and the storage battery 4 is charged by converting the AC power into DC power by the conversion unit 3. can do. When the AC power from the AC input terminal 2 is abnormal, the switching unit disconnects the power system of the AC input terminal 2 and switches the DC power of the storage battery 4 to AC by the conversion unit 3 and supplies it to the load 20. be able to. Alternatively, during normal operation, the converter 3 charges the storage battery 4 with the DC power converted from the AC power of the AC input terminal 2 and converts the DC power from the storage battery 4 into AC power corresponding to the load 20 again. An output method may be used.

(Operation example of the control unit 8 and the communication unit 7)
The control unit 8 can be configured by a general-purpose or dedicated processor, for example. The monitoring unit 6 monitors the state of the storage battery 4 and generates data indicating the state of the storage battery 4. For example, the monitoring unit 6 can monitor the temperature, current, voltage, remaining amount, and the like of the storage battery 4 and generate data indicating these values. Data indicating the state of the storage battery 4 generated by the monitoring unit 6 is output to the outside via the battery management unit 16, the control unit 8, and the communication unit 7. Note that the battery management unit 16 may output the data acquired from the monitoring unit 6 to the communication unit 7 without using the control unit 8.

  As an example, when the storage battery 4 is configured by a plurality of lithium ion batteries, the monitoring unit 6 can be configured by a BMU (battery management unit) that monitors and controls each battery. Further, the battery management unit 16 can be realized by a BMS (Battery Management System) that collects data from a plurality of batteries and controls the plurality of batteries.

  The communication unit 7 is a communication interface for the power storage device 1 to perform data communication with the outside. Communication between the communication unit 7 and the external device may be performed by wireless communication. Further, the communication unit 7 can enable communication with an external device connected to a network such as the Internet via an external router, for example. Accordingly, in addition to the data indicating the battery temperature, current, voltage, remaining amount, and the like from the power storage device 1 to the external management device (for example, a management server) via the communication unit 7, the power storage device 1 Identification information, information indicating a position, a connection state with another device, and the like can be transmitted.

  The management device that can communicate with the communication unit 7 can be configured to be able to communicate with devices other than the power storage device 1. In this case, the management device can collect information on the power storage device 1 and devices related to the power storage device 1. The management device can transmit control data indicating an appropriate operation instruction to the power storage device 1 based on the collected information. In this case, the power storage device 1 can perform an appropriate operation corresponding not only to the internal state but also to the external environment.

  Thus, in order for the power storage device 1 to operate in cooperation with other devices, for example, the communication unit 7 can communicate with an external management device using a specific protocol. The specific protocol is preferably used in common for communication between a plurality of types of devices different from the power storage device 1 and the management device. For example, a protocol used in an energy management system such as HEMS (Home Energy Management System) can be adopted as the specific protocol. Examples of the HEMS communication protocol include SEP 2.0 (Smart Energy Profile 2.0), ECHONET Lite, and the like. In particular, the ECHONET Lite system is a communication system suitable for an energy management system, and the versatility can be increased by applying this system.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. For example, in the example shown in FIG. 2, the conversion unit 3 has a configuration using a transformer-less non-insulated converter, but the present invention is also applied to a power storage device having the conversion unit 3 including a transformer. I can.

DESCRIPTION OF SYMBOLS 1 Power storage device 2 AC input terminal 3 Conversion unit 4 Storage battery 5 Power supply unit 6 Monitoring unit 7 Communication unit 8 Control unit 9 AC output terminal 16 Battery management unit 20 Load

Claims (6)

AC input terminal for inputting AC power from the outside,
A storage battery,
A converter that converts alternating current power input from the alternating current input terminal into direct current power and outputs the direct current power to the storage battery, and converts direct current power output from the storage battery into alternating current power, and
AC output terminal for outputting AC power converted by the converter,
A battery management unit that acquires information indicating the state of the storage battery and controls charging and discharging of the storage battery;
A first power supply unit that converts the AC power input from the AC input terminal and supplies power to the conversion unit;
A power storage device comprising: a second power supply unit that converts the AC power input from the AC input terminal and supplies power to the battery management unit.   The power storage device according to claim 1, wherein the conversion unit connects the AC input terminal and the storage battery without insulation using a transformer-less converter.   The power storage device according to claim 1, wherein each of the first power supply unit and the second power supply unit includes an insulation type converter. At least one battery pack including a plurality of the storage batteries;
A battery monitoring unit that is provided for each battery pack and that monitors a state of a storage battery included in the battery pack;
The battery monitoring unit is connected without being insulated from the AC input terminal,
The power storage device according to any one of claims 1 to 3, wherein the battery management unit acquires information indicating a state of the storage battery from the battery monitoring unit, and controls charge / discharge of the storage battery. A communication unit that transmits data indicating the state of the storage battery to the outside and receives control data generated based on the data indicating the state of the storage battery from the outside,
Based on the control data, a control unit for controlling the operation of the storage battery,
A third power supply unit that converts the AC power input from the AC input terminal and supplies power to the control unit;
The power storage device according to claim 1, further comprising: a fourth power supply unit that converts the AC power input from the AC power terminal and supplies power to the communication unit. .   The power storage device according to claim 1, wherein the storage battery is a lithium ion storage battery.

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