Management device, power system

Abstract

In order to simplify the wiring of a power supply system (1) having a management device (10-50) and a plurality of power storage modules (M1-M3), a plurality of sub-management units (10-30) respectively manage the plurality of power storage modules (M1-M3). The main management unit (50) manages the plurality of power storage modules (M1-M3) via the plurality of sub-management units (10-30). The main management unit (50) and the plurality of sub-management units (10-30) are daisy-chain connected via a power line (40v). The main management unit (50) can supply power to the plurality of sub-management units (10-30) from the power storage unit (2) other than the plurality of power storage modules (M1-M3) via the power line (40v). The main management unit (50) and the plurality of sub-management units (10-30) respectively include a communication unit (12-32). Each communication unit (12-32) superimposes a communication signal on the power line (40v).

Description

Technical Field

[0001] The present invention relates to a management device and a power supply system for managing the state of a power storage unit. Background Art

[0002] In recent years, hybrid vehicles (HV: Hybrid Electric Vehicle), plug-in hybrid vehicles (PHV: Plug-in Hybrid Electric Vehicle), and electric vehicles (EV: Electric Vehicle) have become increasingly popular. These vehicles are equipped with secondary batteries as key equipment. As secondary batteries for vehicles, nickel-metal hydride batteries and lithium-ion batteries are mainly popular. It is expected that lithium-ion batteries with high energy density will be popularized more rapidly in the future.

[0003] The normal use area and the prohibited use area of ​​lithium-ion batteries are close to each other, so stricter voltage management is required compared with other types of batteries. Generally, in lithium-ion batteries, from the perspective of maintaining power efficiency and ensuring safety, an equalization process is performed to equalize the voltage between multiple cells connected in series (for example, see Patent Document 1).

[0004] Generally, a high-voltage power supply system is composed of a plurality of storage modules including a plurality of cells connected in series connected in series. A storage stack equipped with each storage module is provided with a voltage detection circuit for detecting each voltage of a plurality of cells included in the storage module and an equalization circuit for performing equalization processing between the plurality of cells. The voltage detection circuit sends the detected voltage value to a management device for managing the plurality of storage stacks as a whole via a communication line. The equalization circuit performs equalization processing based on a control signal received from the management device via a communication line.

[0005] The mainstream equalization method is a passive method, in which a discharge resistor is connected to each of a plurality of cells connected in series, and cells other than the cell with the lowest voltage are discharged so that the voltages of the other cells match the voltage of the cell with the lowest voltage.

[0006] As another method of equalization, there is an active method. In the active method, a charging circuit is provided to charge the cells other than the cell with the highest voltage among the multiple cells connected in series so that the voltages of the other cells are consistent with the voltage of the cell with the highest voltage. As a power source for charging, the storage module itself including the cell to be charged can be used, or an external auxiliary battery (for example, a lead battery with a 12V output) can be used.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2013-21851 Summary of the invention

[0010] Problem that the invention aims to solve

[0011] Regarding the power supply voltage of the IC and active elements in the battery stack, there are two methods of obtaining it from the battery module in the battery stack and obtaining it from the auxiliary battery. In the case of obtaining power from the auxiliary battery, the circuit board of the battery stack and the circuit board of the management device are basically connected by two systems of wire harnesses, namely, communication lines and power lines. In addition, even when the power supply voltage of the IC and active elements in the battery stack is obtained from the battery module in the battery stack, in the case of using a single-cell active balancing method in which the power supply for charging is obtained from the outside, the two are also connected by two systems of wire harnesses.

[0012] When the two are connected by two wiring harnesses, the wiring in the power supply system becomes complicated and the wiring cost increases.

[0013] The present invention has been made in view of such circumstances, and an object of the present invention is to provide a technology for simplifying wiring of a power supply system including a management device and a plurality of power storage modules.

[0014] Solutions for solving problems

[0015] In order to solve the above-mentioned problems, a management device of a certain mode of the present invention comprises: a plurality of sub-management units, each of which manages a plurality of power storage modules, each of which includes a plurality of cells connected in series; and a main management unit, which manages the plurality of power storage modules via the plurality of sub-management units. The main management unit and the plurality of sub-management units are daisy-chained via a power line, and the main management unit can supply power from a power storage unit other than the plurality of power storage modules to the plurality of sub-management units via the power line, and the main management unit and the plurality of sub-management units each include a communication unit. Each communication unit superimposes a communication signal on the power line.

[0016] Effects of the Invention

[0017] According to the present invention, it is possible to simplify the wiring of a power supply system including a management device and a plurality of power storage modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a diagram showing the configuration of a power supply system according to a comparative example.

[0019] Figure 2It is a diagram showing the configuration of a power supply system according to an embodiment of the present invention.

[0020] Figure 3 Yes means Figure 2 A diagram of a structural example of a third sub-management unit.

[0021] Figure 4 It is a diagram schematically showing the input voltage input to the third sub-management unit via the power line.

[0022] Figure 5 It is a diagram showing the configuration of a power supply system according to a modification. DETAILED DESCRIPTION

[0023] Figure 1 1 is a diagram showing a configuration of a power supply system 1 according to a comparative example. The power supply system 1 includes a plurality of power storage modules ( Figure 1 The first power storage module M1 to the third power storage module M3), multiple sub-management units (in Figure 1 The first sub-management unit 10 to the third sub-management unit 30 ), and the main management unit 50 .

[0024] The first power storage module M1 is a plurality of cells (in Figure 1 The second power storage module M2 is formed by connecting a plurality of monomers (in Figure 1 The third power storage module M3 is formed by connecting a plurality of cells (in Figure 1 In the example, the eleventh monomer E11 to the fifteenth monomer E15 are connected in series. Figure 1 The structure of the power storage modules M1 to M3 shown is simplified, and the actual structure is often a structure in which more cells are connected in series according to the voltage required by the power supply system 1 .

[0025] Each cell can be a lithium ion battery cell, a nickel-metal hydride battery cell, a lead battery cell, an electric double layer capacitor cell, a lithium ion capacitor cell, etc. Hereinafter, in this specification, an example of using a lithium ion battery cell (nominal voltage: 3.6V-3.7V) is assumed.

[0026] The first power storage module M1 and the first sub-management unit 10 form a power storage stack. The first sub-management unit 10 includes an ASIC (Application Specific Integrated Circuit) 11, a communication unit 12, and an isolated DC / DC (Direct Current-Direct Current) converter 13, which are mounted on a circuit substrate. In addition, the communication unit 12 may be incorporated into the ASIC 11.

[0027] Similarly, the second power storage module M2 and the second sub-management unit 20 also form a power storage stack, and the second sub-management unit 20 includes an ASIC 21, a communication unit 22, and an isolated DC / DC converter 23. Similarly, the third power storage module M3 and the third sub-management unit 30 also form a power storage stack, and the third sub-management unit 30 includes an ASIC 31, a communication unit 32, and an isolated DC / DC converter 33.

[0028] The main management unit 50 includes a control unit 51, a communication unit 52, and a power switch 53, which are mounted on a circuit board. The control unit 51 is composed of, for example, a microcomputer. The communication unit 52 may be incorporated into the microcomputer.

[0029] The ASIC 11 of the first sub-management unit 10 includes a voltage detection circuit 11a and an equalization circuit 11b. The voltage detection circuit 11a is connected to each node of a plurality of cells E1-E5 connected in series through a plurality of voltage lines, and detects the voltage between two adjacent voltage lines, thereby detecting the voltage of each cell E1-E5. The voltage detection circuit 11a includes a multiplexer and an A / D converter (not shown). The multiplexer is used to output the voltage values ​​of the plurality of cells E1-E5 to the AD converter in a prescribed order, and the AD converter converts the analog signal input from the multiplexer into a digital value. The voltage values ​​of the plurality of cells E1-E5 converted into digital values ​​by the AD converter are output to the communication unit 12.

[0030] The equalization circuit 11b is used to equalize the plurality of cells E1-E5 included in the first power storage module M1. In this comparative example, the equalization circuit 11b uses a cell active balancing method to equalize the voltages and capacities among the plurality of cells E1-E5. A configuration example of the equalization circuit 11b will be described later.

[0031] The communication unit 12 sends the voltage values ​​of the multiple cells E1-E5 included in the first power storage module M1 input from the voltage detection circuit 11a to the main management unit 50 via the communication line 40c. The first sub-management unit 10-the third sub-management unit 30 and the main management unit 50 are daisy-chained through the communication line 40c. In addition, daisy chain connection refers to a connection method in which multiple devices are connected in a row, and a connection method in which signals are transmitted between adjacent devices. Figure 1 In the example shown, the main management unit 50 and the first sub-management unit 10 are respectively set as terminals, and the adjacent main management unit 50 and the third sub-management unit 30, the third sub-management unit 30 and the second sub-management unit 20, and the second sub-management unit 20 and the first sub-management unit 10 are connected by communication lines 40c. Figure 1 In the example shown, the communication line 40c is constituted by differential wiring (two-wire) having high noise resistance, but it may be constituted by a single wire or four wires.

[0032] The communication unit 12 of the first sub-management unit 10 transmits the voltage values ​​of the plurality of cells E1-E5 included in the first power storage module M1 to the control unit 51 of the main management unit 50 via the communication unit 22 of the second sub-management unit 20, the communication unit 32 of the third sub-management unit 30, and the communication unit 52 of the main management unit 50. The communication unit 22 of the second sub-management unit 20 transmits the voltage values ​​of the plurality of cells E6-E10 included in the second power storage module M2 to the control unit 51 of the main management unit 50 via the communication unit 32 of the third sub-management unit 30 and the communication unit 52 of the main management unit 50. The communication unit 32 of the third sub-management unit 30 transmits the voltage values ​​of the plurality of cells E11-E15 included in the third power storage module M3 to the control unit 51 of the main management unit 50 via the communication unit 52 of the main management unit 50.

[0033] In addition, when each battery stack is equipped with at least one temperature sensor (for example, a thermistor) for detecting the temperature of multiple cells included in each battery module, in addition to sending the voltage values ​​of the multiple cells to the control unit 51, each communication unit 12-32 of the first sub-management unit 10-the third sub-management unit 30 also sends the temperature values ​​of the multiple cells detected by the at least one temperature sensor to the control unit 51.

[0034] The communication between the communication unit 12 of the first sub-management unit 10, the communication unit 22 of the second sub-management unit 20, the communication unit 32 of the third sub-management unit 30, and the communication unit 52 of the main management unit 50 can use a predetermined serial communication method. For example, SPI (Serial Peripheral Interface), I2C (Inter-Integrated Circuit), UART (Universal Asynchronous Receiver / Transmitter) can be used. In addition, a manufacturer's own communication method based on these communication methods can also be used.

[0035] The communication unit 12 of the first sub-management unit 10 includes a communication terminal of one system. The single-port communication terminal of the communication unit 12 is connected to a communication connector via a differential wiring. A capacitor C11 and a capacitor C12 are inserted into the differential wiring, respectively.

[0036] The communication unit 22 of the second sub-management unit 20 has two communication terminals, an upstream port and a downstream port. The communication terminal of the upstream port of the communication unit 22 is connected to the upstream connector via a differential wiring. Capacitors C21 and C22 are inserted into the differential wiring, respectively. The communication terminal of the downstream port of the communication unit 22 is connected to the downstream connector via a differential wiring. Capacitors C23 and C24 are inserted into the differential wiring, respectively.

[0037] The communication unit 32 of the third sub-management unit 30 also has two communication terminals, an upstream port and a downstream port. The communication terminal of the upstream port of the communication unit 32 is connected to the upstream connector via a differential wiring. A capacitor C31 and a capacitor C32 are inserted into the differential wiring, respectively. The communication terminal of the downstream port of the communication unit 32 is connected to the downstream connector via a differential wiring. A capacitor C33 and a capacitor C34 are inserted into the differential wiring, respectively.

[0038] The communication unit 52 of the main management unit 50 includes a communication terminal of one system. The single-port communication terminal of the communication unit 52 is connected to a communication connector via a differential wiring. A capacitor C51 and a capacitor C52 are inserted into the differential wiring, respectively.

[0039] The communication connector of the first sub-management unit 10 and the downlink connector of the second sub-management unit 20, the uplink connector of the second sub-management unit 20 and the downlink connector of the third sub-management unit 30, and the uplink connector of the third sub-management unit 30 and the communication connector of the main management unit 50 are respectively connected by communication lines 40c (differential wiring).

[0040] Capacitors C11-C12, C21-C24, C31-C34, and C51-C52 are capacitors for blocking direct current for isolating two adjacent communication units connected by the communication line 40c. In addition, in the above-mentioned embodiment, as an insulating circuit for enabling communication between circuits with different ground potentials, a structure including capacitors C11-C12, C21-C24, C31-C34, and C51-C52 is used, but these insulating circuits can also be constructed using other elements such as transformers.

[0041] The control unit 51 of the main management unit 50 obtains voltage values ​​and temperature values ​​of the plurality of cells E1-E15 from the first to third sub-management units 10-30 via the communication line 40c. The control unit 51 also obtains current values ​​flowing through the plurality of power storage modules M1-M3 detected by a current detection unit (not shown).

[0042] The control unit 51 estimates the State Of Charge (SOC) and State Of Health (SOH) of the plurality of cells E1 - E15 based on the current value, the voltage values of the plurality of cells E1 - E15, and the temperature value. The SOC can be estimated, for example, by the Open Circuit Voltage (OCV) method or the current integration method. The OCV method is a method of estimating the SOC based on the detected OCV of the cell and the characteristic data of the pre - held SOC - OCV curve. The current integration method is a method of estimating the SOC based on the OCV at the start of charge and discharge of the detected cell and the integrated value of the detected current.

[0043] The SOH is defined by the ratio of the current full - charge capacity to the initial full - charge capacity. The lower the value (the closer to 0%), the more severe the deterioration. The deterioration of the secondary battery can be approximated by the sum of the storage deterioration and the cycle deterioration.

[0044] The storage deterioration is the deterioration that progresses with time according to the temperature at each time point and the SOC at each time point regardless of whether the secondary battery is being charged or discharged. The higher the SOC at each time point (the closer to 100%) or the higher the temperature at each time point, the faster the storage deterioration rate.

[0045] The cycle deterioration is the deterioration that progresses as the number of charge - discharge cycles increases. The cycle deterioration depends on the used SOC range, temperature, and current rate (in Japanese: 電流レート). The larger the used SOC range, the higher the temperature, or the higher the current rate, the faster the cycle deterioration rate. Thus, the deterioration of the secondary battery depends greatly on the usage environment, and as the usage period becomes longer, the deviation in the capacities of the plurality of cells E1 - E15 becomes larger.

[0046] The control unit 51 of the main management unit 50 performs equalization processing among the plurality of cells E1 - E15 based on the voltage values of the plurality of cells E1 - E15 received from the plurality of sub - management units 10 - 30. In the cell active - balancing method, the other cells among the plurality of cells E1 - E15, except for the cell with the largest capacity, are charged up to the capacity of the cell with the largest capacity (hereinafter referred to as the target value). In addition, the target value can be defined by any one of the actual capacity, SOC, and OCV. When defined by OCV, the OCV of the cell with the highest OCV becomes the target value. In addition, the target value can also be defined by the dischargeable amount or the chargeable amount.

[0047] The control unit 51 calculates the difference between the target value of the cell with the largest capacity among the plurality of cells E1-E15 and the detected value of the other plurality of cells. The control unit 51 calculates the charge amount of the other plurality of cells based on the calculated differences, and calculates the charging time of the other plurality of cells based on the calculated charge amount. The control unit 51 generates an equalization control signal including the charging time of the plurality of cells managed by the sub-management unit for each sub-management unit as a transmission destination, and outputs it to the communication unit 52.

[0048] In addition, a unique ID is pre-assigned to each of the plurality of sub-management units 10-30, and the control unit 51 includes the ID of the sub-management unit in the header area of ​​a packet including a control signal to be sent to a specific sub-management unit. The communication unit 52 transmits the control signal input from the control unit 51 to the plurality of sub-management units 10-30 via the communication line 40c.

[0049] When each communication unit 12-32 of the plurality of sub-management units 10-30 receives a packet including a control signal via the communication line 40c, it determines whether the ID in the packet is the ID of its own sub-management unit. If the ID in the packet is the ID of its own sub-management unit, the control signal included in the received packet is output to the ASIC in the sub-management unit. If the ID in the packet is not the ID of its own sub-management unit, the packet is transferred to the next sub-management unit.

[0050] As described above, as a power source for charging in the single-cell active balancing method, the storage module itself including the single cell to be equalized can be used, or a power source provided outside the power supply system 1 can be used. In this comparative example, the latter is adopted, which can complete equalization in a shorter time than the former. Specifically, the lead battery 2 used as an auxiliary battery in the vehicle is used as a power source for equalization charging. In addition, a nickel-hydrogen battery, a lithium-ion battery, a double-layer capacitor, etc. can be connected in parallel to the lead battery 2 to increase the capacity.

[0051] The main management unit 50 can supply the power supply voltage (e.g., 12V DC voltage) supplied from the lead battery 2 to the first sub-management unit 10 to the third sub-management unit 30 via the power line 40v. The power switch 53 of the main management unit 50 is a switch for switching between supplying the power supplied from the lead battery 2 to the first sub-management unit 10 to the third sub-management unit 30 and cutting off the supply of the power to the first sub-management unit 10 to the third sub-management unit 30. The first sub-management unit 10 to the third sub-management unit 30 are connected to the main management unit 50 via the power line 40v. Figure 1In the example shown, the main management unit 50 and the third sub-management unit 30, the third sub-management unit 30 and the second sub-management unit 20, and the second sub-management unit 20 and the first sub-management unit 10 are connected by power lines 40v. The power lines 40v are composed of two lines, a positive line and a negative line.

[0052] The potential of the power line 40v connecting the first sub-management unit 10, the second sub-management unit 20, the third sub-management unit 30, and the main management unit 50 is substantially the same. Figure 1 In the example shown, the power line 40v is configured to be branched within each sub-management unit 10-30, but the power line 40v may be configured to be branched outside each sub-management unit 10-30.

[0053] The insulating DC / DC converter 13 of the first sub-management unit 10 converts the DC voltage inputted via the power line 40v into a DC voltage for charging and outputs it to the equalization circuit 31b. In addition, when the power supply of the ASIC 11 is provided by the power supply of the lead battery 2, the insulating DC / DC converter 13 uses the DC voltage inputted via the power line 40v to generate a DC voltage for charging and a power supply voltage of the ASIC 11. The insulating DC / DC converter 23 of the second sub-management unit 20 and the insulating DC / DC converter 33 of the third sub-management unit 30 are similar.

[0054] In the comparative example shown above, the first sub-management unit 10, the second sub-management unit 20, the third sub-management unit 30, and the main management unit 50 are connected by two wiring harnesses, namely the communication line 40c and the power line 40v, which complicates the wiring and increases the wiring cost.

[0055] Figure 2 1 is a diagram showing a configuration of a power supply system 1 according to an embodiment of the present invention. Figure 1 The differences in the structures involved in the comparative example shown are described. In the embodiment, the communication line 40c is omitted, and the communication signal between the main management unit 50 and the plurality of sub-management units 10-30 is superimposed on the power line 40v and transmitted. The communication units 12-32 of the plurality of sub-management units 10-30 and the communication unit 52 of the main management unit 50 include a PLC (Power Line Communication) modem. The PLC modem performs, for example, low-speed PLC communication using a frequency band of 10kHz-450kHz or high-speed PLC communication using a frequency band of 2MHz-30MHz.

[0056] The connector CN5 of the main management unit 50 connecting the power line 40v is connected to the power switch 53 in the main management unit 50 through an internal power line. A differential signal line is branched from the connection point Na on the internal power line, and the differential signal line is connected to the communication terminal of the communication unit 52. A low-pass filter 54 is inserted in the internal power line. The low-pass filter 54 is inserted between the connection point Na and the power switch 53 on the internal power line. The low-pass filter 54 is used to remove high-frequency components in the power input from the power switch 53. The low-pass filter 54 can use an LC filter or an RC filter, for example. Capacitors C51 and C52 are inserted in the above-mentioned differential signal line. Capacitors C51 and C52 are DC isolation capacitors that insulate the communication unit 52 from the internal power line.

[0057] The connector CN5 of the main management unit 50 is connected to the first connector CN31 of the third sub-management unit 30 through a power line 40v. In the third sub-management unit 30, the first connector CN31 and the second connector CN32 are connected through an internal power line L1. A power branch line is branched from a connection point Na of the internal power line L1, and the power branch line is connected to the insulating DC / DC converter 33. A low-pass filter 34 is inserted into the power branch line. The low-pass filter 34 is used to remove high-frequency components from the power input from the connection point a of the internal power line L1 and output it to the insulating DC / DC converter 33. The low-pass filter 34 can also use, for example, an LC filter or an RC filter.

[0058] A first differential signal wiring is branched from a first connection point N1 of the internal power line L1 of the third sub-management unit 30, and the first differential signal wiring is connected to the communication terminal of the upstream port of the communication unit 32. A capacitor C31 and a capacitor C32 are inserted into the first differential signal wiring. A second differential signal wiring is branched from a second connection point N2 of the internal power line L1 of the third sub-management unit 30, and the second differential signal wiring is connected to the communication terminal of the downstream port of the communication unit 32. A capacitor C33 and a capacitor C34 are inserted into the second differential signal wiring.

[0059] Capacitors C31-C34 are capacitors for DC isolation for DC insulation between the communication unit 32 and the internal power line L1. A low-pass filter 35 is inserted between the first connection point N1 and the second connection point N2 on the internal power line L1 of the third sub-management unit 30. The low-pass filter 35 is a filter that allows DC power to pass between the first connection point N1 and the second connection point N2 and cuts off high-frequency components.

[0060] The second connector CN32 of the third sub-management unit 30 is connected to the first connector CN21 of the second sub-management unit 20 through the power line 40v. In the second sub-management unit 20, the first connector CN21 and the second connector CN22 are connected through the internal power line L1. A power branch line is branched from the connection point Na of the internal power line L1, and the power branch line is connected to the insulating DC / DC converter 23. A low-pass filter 24 is inserted into the power branch line. The low-pass filter 24 is used to remove the high-frequency component of the power input from the connection point a of the internal power line L1 and output it to the insulating DC / DC converter 23.

[0061] A first differential signal wiring is branched from a first connection point N1 of the internal power line L1 of the second sub-management unit 20, and the first differential signal wiring is connected to the communication terminal of the upstream port of the communication unit 22. Capacitors C21 and C22 are inserted into the first differential signal wiring. A second differential signal wiring is branched from a second connection point N2 of the internal power line L1 of the second sub-management unit 20, and the second differential signal wiring is connected to the communication terminal of the downstream port of the communication unit 22. Capacitors C23 and C24 are inserted into the second differential signal wiring.

[0062] Capacitors C21-C24 are capacitors for blocking direct current for isolating the communication unit 22 from the internal power line L1. A low-pass filter 25 is inserted between the first connection point N1 and the second connection point N2 on the internal power line L1 of the second sub-management unit 20. The low-pass filter 25 is a filter that allows direct current power to pass between the first connection point N1 and the second connection point N2 and cuts off high-frequency components.

[0063] The second connector CN22 of the second sub-management unit 20 is connected to the connector CN1 of the first sub-management unit 10 via a power line 40v. In the first sub-management unit 10, the connector CN1 is connected to the insulating DC / DC converter 13 via an internal power line L1. A low-pass filter 14 is inserted into the internal power line L1. The low-pass filter 14 is used to remove high-frequency components from the input power and output it to the insulating DC / DC converter 13.

[0064] A differential signal wiring is branched from the connection point Na of the internal power line L1 of the first sub-management unit 10, and the differential signal wiring is connected to the communication terminal of the communication unit 12. Capacitors C11 and C12 are inserted into the differential signal wiring, respectively. Capacitors C11 and C12 are DC blocking capacitors that insulate the communication unit 12 from the connection point Na.

[0065] Figure 3 Yes means Figure 2 FIG. 3 is a diagram showing an example of the structure of the third sub-management unit 30. Figure 3In the illustrated configuration example, the equalization circuit 31b includes a switch control circuit 31ba and a cell selection circuit 31bb. The cell selection circuit 31bb includes a plurality of switches S30-S39.

[0066] exist Figure 3 In FIG. 3 , the isolated DC / DC converter 33 is composed of an isolated flyback DC / DC converter. The isolated flyback DC / DC converter includes a transformer T3, a switch S3, and a diode D3. Figure 3 In the isolated flyback DC / DC converter shown, the primary winding and the secondary winding of the transformer T3 are connected with opposite polarities. In addition, the isolated DC / DC converter 33 is not limited to the isolated flyback DC / DC converter, and can be an isolated power supply circuit and can have any structure. As such a power supply circuit, in addition to the above-mentioned isolated flyback DC / DC converter, an isolated forward DC / DC converter is also known.

[0067] Both ends of the primary winding of transformer T3 are connected to power line 40v via low-pass filter 34. Switch S3 is inserted between one end of the primary winding and the negative line of power line 40v. One end of the secondary winding of transformer T3 is connected to a rectifying diode D3.

[0068] The secondary winding of the transformer T3 is connected to both ends of any one of the multiple monomers E11-E15 via multiple switches S30-S39. Voltage lines are connected to each node of the multiple monomers E11-E15. The first voltage line, the third voltage line, and the fifth voltage line are connected by the positive electrode wiring Lp3, and the second voltage line, the fourth voltage line, and the sixth voltage line are connected by the negative electrode wiring Lm3. Switches S30-S35 are inserted in the first voltage line to the sixth voltage line, respectively.

[0069] The terminal on the current output side of the secondary winding of the transformer T3 is connected to the positive electrode wiring Lp3 via a switch S36, and the terminal on the current output side of the secondary winding is connected to the negative electrode wiring Lm3 via a switch S37. The terminal on the current input side of the secondary winding of the transformer T3 is connected to the positive electrode wiring Lp3 via a switch S39, and the terminal on the current input side of the secondary winding is connected to the negative electrode wiring Lm3 via a switch S38.

[0070] The switch control circuit 31 ba controls the on / off of the switch S3 of the isolated flyback DC / DC converter and the plurality of switches S30 to S39 of the cell selection circuit 31 bb based on the equalization control signal input from the communication unit 32 .

[0071] The switch control circuit 31ba controls two switches, switches S36 / S37, and switches S38 / S39, which are inserted into two voltage lines connected to nodes at both ends of the monomer to be charged, to be in an on state. For example, when charging the monomer E11, switches S30, S31, S36, and S38 are controlled to be in an on state. In addition, when charging the monomer E12, switches S31, S32, S37, and S39 are controlled to be in an on state. The on time of each monomer is in accordance with the charging time of each monomer included in the control signal received from the control unit 51 of the main management unit 50. In addition, the order of charging the plurality of monomers E11-E15 can be in the order of charging time from the longest to the shortest, or can be charged sequentially from the top.

[0072] The switch control circuit 31ba may be a structure that performs PWM (Pulse Width Modulation) control on the switch S3. In addition, depending on the circuit structure, there is a case where the ground potential of the switch control circuit 31ba is different from the ground potential of the circuit including the switch S3. In the case of such a structure, the control signal from the switch control circuit 31ba is insulated via the insulation circuit. The insulated flyback DC / DC converter outputs a charging voltage after stepping down the voltage of the lead battery 2. When a single cell is connected to the output side of the insulated flyback DC / DC converter, a charging current flows in accordance with the voltage of the single cell, but by performing PWM control on the switch S3, the current amount of the charging current can be adjusted. In this way, the output of the insulated flyback DC / DC converter can be adjusted by the turns ratio of the primary winding and the secondary winding of the transformer T3 and the duty cycle of the switch S3. In addition, charging control can be performed in various ways. As charging control, a constant current constant voltage system (CC-CV) is typically known, but any configuration may be used as long as the target cell can be charged using the DC voltage supplied from the lead battery 2 .

[0073] exist Figure 3 In the illustrated configuration example, an LC filter composed of an inductor L31, an inductor L32, and a capacitor C30 is used as a low-pass filter 34 inserted in the front stage of the insulating DC / DC converter 33. The LC filter is used to remove the communication signal (high-frequency pulse signal) and common mode noise superimposed on the power line 40v.

[0074] exist Figure 3In the illustrated structural example, an inductor L33 and an inductor L34 are used as a low-pass filter 35 inserted between the first connection point N1 and the second connection point of the internal power line L1 of the third sub-management unit 30. The inductor L33 and the inductor L34 are used to remove the communication signal (high-frequency pulse signal) and common mode noise superimposed on the power line 40v. Therefore, the DC voltage supplied from the lead battery 2 is transmitted from the first connector CN31 to the second connector CN32 via the low-pass filter 35, and the communication signal is transmitted from the first connector CN31 to the second connector CN32 via the communication unit 32.

[0075] Figure 4 4 is a diagram schematically showing an input voltage input to the third sub-management unit 30 via the power line 40v. The input voltage input to the third sub-management unit 30 via the power line 40v is superimposed with a 12V DC voltage generated by the lead battery 2 and a high-frequency pulse signal generated by the communication unit 52 of the main management unit 50. The 12V DC voltage after the high-frequency pulse signal is removed by the low-pass filter 34 is input to the insulation type DC / DC converter 33. The high-frequency pulse signal after the 12V DC voltage is blocked by the capacitor C31 and the capacitor C32 is input to the communication unit 32 of the third sub-management unit 30.

[0076] In addition, at the second connection point N2, the high-frequency pulse signal sent from the communication unit 32 is superimposed on the 12V DC voltage input via the low-pass filter 35, and the superimposed voltage is output from the second connector CN32 to the second sub-management unit 20 via the power line 40v.

[0077] The structure of the third sub-management unit 30 described above is also similarly applied to the second sub-management unit 20 and the first sub-management unit 10. When applied to the first sub-management unit 10, the inductor L33, the inductor L34, the capacitor C33, the capacitor C34, and the second connector CN32 are not required.

[0078] As described above, according to the present embodiment, the main management unit 50 and the plurality of sub-management units 10-30 are connected by the power line 40v, not by two systems, the power line 40v and the communication line 40c, and the communication signal is superimposed on the power line 40v. Thus, the wiring harness between the main management unit 50 and the plurality of sub-management units 10-30 can be made into one system, thereby simplifying the wiring. In addition, the increase in wiring cost can be suppressed.

[0079] Furthermore, by equalizing the plurality of cells E1 to E15 using a cell active balancing method using an external power source (lead battery 2), it is possible to complete equalization in advance without wasting the energy of the plurality of cells E1 to 15.

[0080] The present invention has been described above based on the embodiments. It should be understood by those skilled in the art that the embodiments are illustrative only and that various modifications can be made to the combinations of their components and processing steps, and such modifications are also within the scope of the present invention.

[0081] Figure 5 It is a diagram showing the configuration of a power supply system 1 according to a modification. Figure 5 The circuit structure shown is Figure 2 The capacitors C11-C12, C21-C22, C23-C24, C31-C32, C33-C34, and C51-C52 of the circuit structure shown are replaced by transformers T11, T21, T22, T31, T32, and T51, respectively. By using a transformer, the communication unit and the power line can be insulated more reliably.

[0082] In addition, in the above-mentioned embodiment, an example of an equalization circuit using a single-cell active balancing method is described. In this regard, an equalization circuit using a single-cell passive balancing method may also be used. In this case, the DC voltage supplied by the lead battery 2 and stepped down by the insulating DC / DC converter 13-33 is used as the power supply voltage of the ASIC 11-31 or the power supply voltage of the active element. In the above-mentioned embodiment, an example of a low-pass filter and a DC blocking filter composed of passive elements such as an inductor and a capacitor is described, but when active elements such as an operational amplifier and a photocoupler are used in the low-pass filter and the DC blocking filter, a power supply voltage is required.

[0083] In addition, in the above-mentioned embodiment, the communication unit 12 of the first sub-management unit 10 and the communication unit 52 of the main management unit 50 may be configured as a two-port structure similarly to the communication unit 22 of the second sub-management unit 20 and the communication unit 32 of the third sub-management unit 30, and the first sub-management unit 10 and the main management unit 50 may be connected via another power line 40v, thereby configuring a ring-type daisy chain connection. In this case, the superposition and stability of communication and power supply are improved. In addition, the power consumption between the communication unit 12 of the first sub-management unit 10, the communication unit 22 of the second sub-management unit 20, and the communication unit 32 of the third sub-management unit 30 is further averaged.

[0084] Furthermore, the embodiment can be determined by the following items.

[0085] [Project 1]

[0086] A management device (10-50), characterized by comprising:

[0087] A plurality of sub-management units (10-30), each of which manages a plurality of power storage modules (M1-M3), each of which includes a plurality of cells (E1-E5, E6-E10, E1-E15) connected in series; and

[0088] a main management unit (50) that manages the plurality of power storage modules (M1-M3) via the plurality of sub-management units (10-30);

[0089] The main management unit (50) and the plurality of sub-management units (10-30) are daisy-chain connected via a power line (40v).

[0090] The main management unit (50) can supply power to the plurality of sub-management units (10-30) from a power storage unit (2) other than the plurality of power storage modules (M1-M3) via the power line (40v).

[0091] The main management unit (50) and the plurality of sub-management units (10-30) each include a communication unit (12-32),

[0092] Each communication unit (12-32) superimposes a communication signal on the power line (40v).

[0093] Accordingly, the wiring between the plurality of sub-management units (10-30) and the main management unit (50) can be simplified.

[0094] [Project 2]

[0095] The management device (10-50) according to item 1 is characterized in that:

[0096] The sub-management unit (30) further includes:

[0097] a voltage detection circuit (31a) for detecting each voltage of a plurality of cells (E11-E15) included in the power storage module (M3); and

[0098] An equalization circuit (31b) for equalizing the capacity / voltage of a plurality of cells (E11-E15) included in the power storage module (M3),

[0099] The communication unit (32) sends the voltages of the plurality of monomers (E11-E15) detected by the voltage detection circuit (31a) to the main management unit (50) via the power line (40v), and receives a control signal for controlling the equalization circuit (31b) from the main management unit (50) via the power line (40v).

[0100] According to this, the plurality of cells (E1-E5, E6-E10, E1-E15) included in the plurality of power storage modules (M1-M3) can be equalized by utilizing the communication between the main management unit (50) and the plurality of sub-management units (10-30).

[0101] [Item 3]

[0102] The management device (10-50) according to item 2 is characterized in that:

[0103] The sub-management unit (30) further includes a DC / DC converter (33) for converting a DC voltage supplied from a power storage unit (2) other than the plurality of power storage modules (M1-M3) via the power line (40v) into a predetermined DC voltage.

[0104] The equalization circuit (31b) uses the DC voltage converted by the DC / DC converter (33) to charge the cell indicated by the control signal among the plurality of cells (E11-E15) included in the power storage module (M3).

[0105] According to this, single-cell active balancing using an external power supply can be actually used through simple wiring.

[0106] [Item 4]

[0107] The management device (10-50) according to any one of items 1 to 3, characterized in that:

[0108] The sub-management unit (30) further includes:

[0109] a first signal wiring connecting a first connection point (N1) of the power line (L1) and a first communication terminal of the communication unit (32);

[0110] a second signal wiring connecting a second connection point (N2) of the power line (L1) and a second communication terminal of the communication unit (32);

[0111] a first insulating circuit (C31, C32) inserted into the first signal wiring and used for DC insulating the first connection point (N1) from the first communication terminal;

[0112] a second insulating circuit (C33, C34) inserted into the second signal wiring and used for DC-insulating the second connection point (N2) from the second communication terminal; and

[0113] A low pass filter (25) is inserted between the first connection point (N1) and the second connection point (N2) of the power line (L1).

[0114] This makes it possible to separate and superimpose the communication signal and the DC voltage.

[0115] [Item 5]

[0116] The management device (10-50) according to item 4 is characterized in that:

[0117] The first insulating circuit (C31, C32) is a capacitor (C31, C32),

[0118] The second insulating circuit (C33, C34) is a capacitor (C33, C34),

[0119] The low-pass filter (35) is an inductor (L33, L34).

[0120] According to this, the circuit can be produced at low cost.

[0121] [Item 6]

[0122] The management device (10-50) according to item 4 is characterized in that:

[0123] The first insulating circuit (T31) is a transformer (T31),

[0124] The second insulating circuit (T32) is a transformer (T32),

[0125] The low-pass filter (35) is an inductor (L33, L34).

[0126] According to this, insulation can be performed more reliably at low cost.

[0127] [Item 7]

[0128] A power supply system (1), characterized by comprising:

[0129] A plurality of power storage modules (M1-M3), each of the plurality of power storage modules (M1-M3) including a plurality of cells (E1-E5, E6-E10, E1-E15) connected in series; and

[0130] A management device (10-50) according to any one of items 1 to 6.

[0131] Accordingly, the wiring between the plurality of sub-management units (10-30) and the main management unit (50) can be simplified.

[0132] Description of Reference Numerals

[0133] 1: power supply system; 2: lead battery; M1-M3: storage module; E1-E15: monomer; 10: first sub-management unit; 20: second sub-management unit; 30: third sub-management unit; 50: main management unit; 11: ASIC; 11a: voltage detection circuit; 11b: equalization circuit; 12: communication unit; 13: insulation type DC / DC converter; 21a: voltage detection circuit; 21b: equalization circuit; 22: communication unit; 23: insulation type DC / DC converter; 31a: voltage detection circuit; 31b: equalization circuit; 31ba: switch control circuit; 31bb: monomer selection circuit; 32: communication unit; 33: insulation type DC / DC converter; 40c: communication line ; 40v: power line; 51: control unit; 52: communication unit; 53: power switch; CN1, CN21, CN22, CN31, CN32, CN5: connector; C13, C14, C21, C22, C23, C24, C21, C22, C23, C24, C31, C32, C33, C34, C51, C52, C30: capacitor; 14, 24, 25, 34, 35, 54: low-pass filter; L1: internal power line; L31, L32, L33, L34: inductor; T3: transformer; S3, S30, S31, S32, S33, S34, S35, S36, S37, S38, S39: switch.

Claims

1. A management device, characterized in that: have: a plurality of sub-management units, each of which manages a plurality of power storage modules, each of which includes a plurality of cells connected in series; and a main management unit that manages the plurality of power storage modules via the plurality of sub-management units, The main management unit and the plurality of sub-management units are daisy-chain connected via power lines. The main management unit can supply a DC voltage from a power storage unit other than the plurality of power storage modules to the plurality of sub-management units via the power line. The main management unit and the plurality of sub-management units respectively include a communication unit, Each communication unit superimposes a communication signal on the DC voltage via the power line. The sub-management unit also includes: a first signal wiring connecting a first connection point of the power line and a first communication terminal of the communication unit; a second signal wiring connecting a second connection point of the power line and a second communication terminal of the communication unit; A first insulating circuit, which is inserted into the first signal wiring and is used to isolate the first connection point from the first communication terminal from direct current; a second insulating circuit, which is inserted into the second signal wiring and is used to isolate the second connection point from the second communication terminal from direct current; and A low pass filter is inserted between the first connection point and the second connection point of the power line.

2. The management device according to claim 1, characterized in that: The sub-management unit also includes: a voltage detection circuit for detecting each voltage of a plurality of cells included in the power storage module; and an equalization circuit for equalizing the capacity or voltage of a plurality of cells included in the power storage module, The communication unit transmits the voltages of the plurality of cells detected by the voltage detection circuit to the main management unit via the power line, and receives a control signal for controlling the equalization circuit from the main management unit via the power line.

3. The management device according to claim 2, characterized in that: The sub-management unit further includes a DC-DC converter configured to convert a DC voltage supplied from a power storage unit other than the plurality of power storage modules via the power line into a predetermined DC voltage. The equalization circuit charges a cell indicated by the control signal among a plurality of cells included in the power storage module using the DC voltage converted by the DC-DC converter.

4. The management device according to claim 1, characterized in that: The first insulating circuit is a capacitor, The second insulating circuit is a capacitor, The low-pass filter is an inductor.

5. The management device according to claim 1, characterized in that: The first insulating circuit is a transformer, The second insulating circuit is a transformer, The low-pass filter is an inductor.

6. A power supply system, characterized in that: have: a plurality of power storage modules, each of the plurality of power storage modules including a plurality of cells connected in series; and A management device according to any one of claims 1 to 5.

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