Power supply control device, power supply device, and power supply control method

Abstract

A power supply control device controls charge and discharge of a power supply device including a plurality of power supply units connected in parallel to a load and a power generation unit, has relationship information indicating a relationship between a discharge current flowing from the power supply device to the load, a discharge current ratio for output current ratios of the plurality of power supply units, and a power loss of the power supply device, acquires a measured value of the discharge current, obtains, from the relationship information, a discharge current ratio at which the power loss of the power supply device corresponding to the acquired measured value of the discharge current is smallest, and adjusts the discharge current ratio so as to match the discharge current ratio obtained from the relationship information.

Description

Technical Field

[0001] This invention relates to a power control device, a power supply device, and a power control method. Background Technology

[0002] A power supply device is known, comprising a battery in which a high-current load (e.g., a starter motor through which a high current flows) and a generator are connected in parallel; a capacitor storing regenerated power generated by the generator; and a DC / DC converter that converts the regenerated power into a voltage corresponding to the capacitor and converts the output of the capacitor into a voltage corresponding to the load (see, for example, JP-A-2016-77124).

[0003] When the internal resistance of a secondary battery changes depending on its state of charge, degradation state, and battery temperature, power loss corresponding to this internal resistance occurs during charging and discharging. In contrast, because capacitors have lower internal resistance, power loss during charging and discharging is suppressed. However, since the inter-terminal voltage of a capacitor varies significantly depending on its state of charge, a DC / DC converter is needed to match the capacitor's inter-terminal voltage to the system voltage (e.g., the voltage of the battery's main power supply). The conversion losses of the DC / DC converter offset the suppression of power loss caused by the capacitor, and the efficiency of the entire system during charging and discharging may deteriorate. This deterioration in efficiency during charging and discharging leads to increased heat generation, necessitating a more robust cooling system to suppress temperature rise. Summary of the Invention

[0004] In view of the above, the purpose of this disclosure is to provide a power control device, power supply device, and power control method that can achieve efficient charging and discharging of secondary batteries.

[0005] According to one aspect of this disclosure, a power control device configured to control the charging and discharging of a power supply device is provided, the power supply device including a plurality of power supply units connected in parallel to a load and a power generation unit. The power control device has relational information indicating a relationship between the discharge current flowing from the power supply device to the load, a discharge current ratio representing the ratio of the output currents of the plurality of power supply units, and the power loss of the power supply device; the power control device acquires a measured value of the discharge current flowing from the power supply device to the load; the power control device obtains from the relational information a discharge current ratio that minimizes the power loss of the power supply device, the power loss of the power supply device corresponding to the acquired measured value of the discharge current flowing from the power supply device to the load; and the power control device adjusts the discharge current ratio set to the power control device to match the discharge current ratio obtained from the relational information.

[0006] According to one aspect of this disclosure, a power control device configured to control the charging and discharging of a power supply device is provided, the power supply device comprising a plurality of power supply units connected in parallel to a load and a power generation unit. The power control device has relational information indicating a relationship between the charging current flowing from the power generation unit to the power supply device, a charging current ratio representing the ratio of the input currents of the plurality of power supply units, and the power loss of the power supply device; the power control device acquires a measured value of the charging current flowing from the power generation unit to the power supply device; the power control device obtains from the relational information a charging current ratio that minimizes the power loss of the power supply device, the power loss of the power supply device corresponding to the acquired measured value of the charging current flowing from the power generation unit to the power supply device; and the power control device adjusts the charging current ratio set to the power control device to match the charging current ratio obtained from the relational information.

[0007] According to one aspect of this disclosure, a power supply device is provided, comprising: a plurality of power supply units connected in parallel with a load and a power generation unit; and the aforementioned power control device configured to control the charging and discharging of the plurality of power supply units.

[0008] According to one aspect of this disclosure, a power control method is provided for charging and discharging a power supply device using computer control, the power supply device comprising a plurality of power supply units connected in parallel to a load and a power generation unit. The power control method includes: providing relationship information indicating a relationship between discharge current flowing from the power supply device to the load, a discharge current ratio representing the ratio of the output currents of the plurality of power supply units, and the power loss of the power supply device; acquiring a measured value of the discharge current flowing from the power supply device to the load; obtaining from the relationship information a discharge current ratio that minimizes the power loss of the power supply device, the power loss of the power supply device corresponding to the acquired measured value of the discharge current flowing from the power supply device to the load; and adjusting the discharge current ratio set to the power control device to match the discharge current ratio obtained from the relationship information.

[0009] According to one aspect of this disclosure, a power control method is provided for charging and discharging a power supply device using computer control, the power supply device comprising a plurality of power supply units connected in parallel to a load and a power generation unit. The power control method includes: providing relationship information indicating a relationship between charging current flowing from the power generation unit to the power supply device, a charging current ratio representing the ratio of input currents of the plurality of power supply units, and power losses of the power supply device; acquiring a measured value of the charging current flowing from the power generation unit to the power supply device; obtaining from the relationship information a charging current ratio that minimizes the power losses of the power supply device, the power losses of the power supply device corresponding to the acquired measured value of the charging current flowing from the power generation unit to the power supply device; and adjusting a charging current ratio set to a power control device to match the charging current ratio obtained from the relationship information.

[0010] According to this disclosure, by setting the charging current ratio or discharging current ratio of multiple power supply units, the power loss of a power supply device including multiple power supply units can be minimized, thereby achieving efficient charging or discharging of the secondary battery. Attached Figure Description

[0011] Figure 1 This is a schematic illustration of a power supply device including a control device according to an embodiment of the present disclosure.

[0012] Figure 2 It is shown Figure 1 The block diagram showing the function of the control device is shown.

[0013] Figure 3 This is a table illustrating examples of the relationship between the discharge current of the power supply unit, the power loss during the discharge of the main power supply unit, the conversion efficiency during the discharge of the voltage conversion unit, and the power loss during the discharge of the auxiliary power supply unit.

[0014] Figure 4 This is a graph illustrating an example of the relationship between the output current of the auxiliary power supply unit and the conversion efficiency of the voltage conversion unit during discharge.

[0015] Figure 5 A graph illustrating the relationship between the output current of the main power supply unit and the power loss of the main power supply unit during discharge, and an example graph illustrating the relationship between the output current of the auxiliary power supply unit and the power loss of the auxiliary power supply unit during discharge.

[0016] Figure 6 This table illustrates the relationship between the discharge current of the power supply unit and the discharge current ratio, as well as the total power loss of the power supply unit when the discharge current flowing from the power supply unit to the load is shared by the main power supply unit and the auxiliary power supply unit.

[0017] Figure 7 A graph showing the relationship between the discharge current of the power supply unit and the discharge current ratio, and the total power loss of the power supply unit when the discharge current flowing from the power supply unit to the load is shared by the main power supply unit and the auxiliary power supply unit.

[0018] Figure 8 It is shown by Figure 1 and Figure 2 The flowchart shown illustrates the charging control process of the control device.

[0019] Figure 9 It is shown by Figure 1 and Figure 2 The flowchart shown illustrates the discharge control process of the control device. Detailed Implementation

[0020] In the following description, this disclosure will be made with reference to preferred embodiments. This disclosure is not limited to the embodiments described below, and appropriate modifications may be made to the embodiments described below without departing from the scope of this disclosure. Although some configurations are not shown or described in the embodiments described below, known or well-known techniques will be appropriately applied to the details of the omitted techniques, provided that there is no contradiction in the following description.

[0021] Figure 1 This is an illustration of a power supply device 1 including a control device 100 according to an embodiment of the present disclosure. Figure 1 As shown, the power supply unit 1 includes a main power supply unit 2, an auxiliary power supply unit 3, current sensors 4, 5, and 6, a voltage sensor 7, and a control device 100. The main power supply unit 2 and the auxiliary power supply unit 3 are connected in parallel to the load (generator unit) L.

[0022] The main power supply unit 2 includes a main secondary battery 21. The main secondary battery 21 is a secondary battery with high energy density, such as a lithium-ion battery. The auxiliary power supply unit 3 includes an auxiliary secondary battery 31 and a voltage conversion unit 32. The auxiliary secondary battery 31 is a secondary battery such as a lithium-ion capacitor or a lithium titanium oxide ion secondary battery, which has a relatively higher output density and a relatively lower internal resistance than the main secondary battery 21. The voltage conversion unit 32 is a DC / DC converter, etc., that matches the voltage of the power supply unit 1 (the voltage of the main secondary battery 21) with the voltage of the auxiliary secondary battery 31. The auxiliary secondary battery 31 and the voltage conversion unit 32 are connected in series.

[0023] Current sensor 4 measures the input / output current of the main power supply unit 2 and transmits the measured value of the input / output current of the main power supply unit 2 to the control device 100. Current sensor 5 measures the input / output current of the auxiliary power supply unit 3 and transmits the measured value of the input / output current of the auxiliary power supply unit 3 to the control device 100. Current sensor 6 measures the charging / discharging current between the power supply unit 1 and the load (generator unit) L and transmits the measured value of the charging / discharging current to the control device 100. Any one of current sensors 4, 5, and 6 (e.g., current sensor 6) can be omitted, and the current measured by the omitted current sensor can be calculated based on the measured values ​​measured by the remaining two current sensors.

[0024] Voltage sensor 7 measures the inter-terminal voltage of the main secondary battery 21 and transmits the measured value to control device 100. Control device 100 estimates the battery state of main power unit 2 and auxiliary power unit 3 based on the measurements transmitted from current sensors 4, 5, 6 and voltage sensor 7. Examples of indicators indicating the battery state of main power unit 2 and auxiliary power unit 3 include the internal resistance and power supply voltage of the main secondary battery 21, and the conversion efficiency of voltage conversion unit 32.

[0025] Power supply unit 1 is either an on-board power supply or a stationary power supply. The main secondary battery 21 and auxiliary secondary battery 31 of power supply unit 1 are charged by receiving power from the power generation unit via a charging circuit (not shown), and the charged power is released to supply power to the load L. When power supply unit 1 is used in a vehicle, the drive motor, air conditioner, various on-board electrical components, etc., serve as the load L. The drive motor serves as both the load L and the power generation unit. When power supply unit 1 is a stationary power supply, household appliances, commercial power systems, LCD displays, communication modules, etc., serve as the load L, and solar power systems, etc., serve as the power generation unit.

[0026] Figure 2 It is shown Figure 1 The block diagram shown illustrates the functions of the control device 100. As shown, the control device 100 includes a battery state analysis unit 101, a mapping generation unit 102, and a current control unit 103.

[0027] Based on the measured values ​​of the input / output current of the main power supply unit 2 transmitted from current sensor 4, the measured values ​​of the input / output current of the auxiliary power supply unit 3 transmitted from current sensor 5, the measured values ​​of the charging / discharging current between the power supply device 1 and the load L transmitted from current sensor 6, and the measured values ​​of the inter-terminal voltage of the main secondary battery 21 transmitted from voltage sensor 7, the battery state analysis unit 101 estimates the battery state of the main power supply unit 2 and the auxiliary power supply unit 3. Specifically, the battery state analysis unit 101 estimates the internal resistance and power supply voltage of the main secondary battery 21, the conversion loss of the voltage conversion unit 32, etc., based on the measurements of current sensors 4, 5, 6 and voltage sensor 7.

[0028] The mapping generation unit 102 has pre-created discharge current ratio mapping and charging current ratio mapping, and updates the discharge current ratio mapping and charging current ratio mapping based on the internal resistance and power supply voltage of the main secondary battery 21 estimated by the battery state analysis unit 101 and the conversion loss of the voltage conversion unit 32. The discharge current ratio mapping is information indicating the relationship between the discharge current flowing from the power supply unit 1 to the load L, the total power loss of the power supply unit 1 during discharge, and the discharge current ratio, which is the ratio of the output current of the main power supply unit 2 to the output current of the auxiliary power supply unit 3.

[0029] The total power loss P of power supply device 1 during discharge. D It is represented by the following formula (1).

[0030] P D =P DM +P DS ...(1)

[0031] P DM The power loss of main power supply unit 2 during discharge, P DS This refers to the power loss of auxiliary power supply unit 3 during discharge.

[0032] Power loss P of main power supply unit 2 during discharge DM Equation (2) represents the power loss P during the discharge of auxiliary power supply unit 3. DS It is represented by the following formula (3).

[0033] P DM =I L 2 ×r m ...(2)

[0034] I L Let r be the discharge current flowing from power supply unit 1 to load L. m The internal resistor of the main power supply unit 2.

[0035] P DS =I L ×V m ×η...(3)

[0036] V m η is the power supply voltage of the main secondary battery 21, and η is the conversion efficiency of the voltage conversion unit (DC / DC converter) 32 of the auxiliary power supply unit 3 during discharge.

[0037] The total power loss P of power supply device 1 during charging D It is represented by the following equation (4).

[0038] P D '=P DM '+P DS '...(4)

[0039] P DM ' is the power loss of main power unit 2 during charging, P DS 'This refers to the power loss during the charging of auxiliary power unit 3.

[0040] Power loss P of main power unit 2 during charging DM The power loss P of the auxiliary power supply unit 3 during charging is expressed by the following equation (5).DS It is represented by the following formula (6).

[0041] P DM '=I L ' 2 ×r m ...(5)

[0042] I L ' is the charging current flowing from the load L to the power supply device 1.

[0043] P DS '=I L '×V m ×η'...(6)

[0044] η' is the conversion efficiency of the voltage conversion unit (DC / DC converter) 32 when the auxiliary power supply unit 3 is charging.

[0045] When calculating the power loss P of auxiliary power supply unit 3 DS P DS In this case, it is assumed that the internal resistance of the secondary battery 31 is low enough (e.g., 0.001Ω), and the loss caused by the internal resistance of the secondary battery 31 is not included in the calculation.

[0046] Figure 3 This indicates the discharge current I of power supply device 1. L The power loss P of main power supply unit 2 during discharge. DM The conversion efficiency η of voltage conversion unit 32 during discharge and the power loss P of auxiliary power supply unit 3 during discharge. DS A table of examples of relationships between them. Figure 4 This is a graph illustrating an example of the relationship between the output current of the auxiliary power supply unit 3 and the conversion efficiency η of the voltage conversion unit 32 during discharge. Figure 5 To illustrate the output current of main power supply unit 2 and the power loss P of main power supply unit 2 during discharge. DM The relationship between the output current of auxiliary power supply unit 3 and the power loss P of auxiliary power supply unit 3 during discharge. DS The graph illustrates the relationship between the two. In this embodiment, it is assumed that the inter-terminal voltage of the main secondary battery 21 is 370V, the internal resistance of the main secondary battery 21 is 0.1Ω, and the internal resistance of the secondary battery 31 is 0.001Ω.

[0047] like Figure 3 The table and Figure 5 As shown in the curve, the power loss P of the main power supply unit 2 DM The power loss P of the auxiliary power supply unit 3 gradually increases as the output current of the main power supply unit 2 increases. In contrast, the power loss P of the auxiliary power supply unit 3... DSThe output current of the auxiliary power supply unit 3 increases or decreases irregularly as the output current increases.

[0048] Figure 6 This shows the discharge current I of power supply device 1. L Compared with the discharge current ratio α, and when the main power supply unit 2 and the auxiliary secondary battery 31 share the discharge current I from the power supply unit 1 to the load. L The total power loss P of power supply device 1 D A table showing the relationships between them. Figure 7 The discharge current I of power supply device 1 L The discharge current ratio α, and the discharge current I shared by the main power supply unit 2 and the secondary secondary battery 31 from the power supply unit 1 to the load L. L The total power loss P of power supply device 1 D A graph showing the relationship between them.

[0049] When the ratio of the output current of the main power supply unit 2 to the output current of the auxiliary power supply unit 3 is 1:0, the discharge current ratio α satisfies α = 1.0, and when the ratio of the output current of the main power supply unit 2 to the output current of the auxiliary power supply unit 3 is 0:1, the discharge current ratio α satisfies α = 0. When the ratio of the output current of the main power supply unit 2 to the output current of the auxiliary power supply unit 3 is 1:1, the discharge current ratio α satisfies α = 0.5.

[0050] like Figure 7 As shown, the total power loss P of power supply device 1 D The outline of the curve with the vertical axis as the ordinate and the discharge current ratio α as the horizontal axis is based on the discharge current I of power supply device 1. L And it changes. For example, when the discharge current I of power supply device 1... L When the current is 100A, the total power loss P of power supply device 1 D The discharge current ratio α gradually decreases as the discharge current ratio α increases. In this case, the total power loss P of the power supply device 1 can be minimized by setting the discharge current ratio α to 1.0. D In contrast, when the discharge current I of power supply device 1... L When the current is 150A, 200A, 250A or 300A, the total power loss P of power supply device 1 D The discharge current ratio α increases or decreases irregularly as the discharge current ratio α increases. When the discharge current I of power supply device 1... L When the current is 150A or 200A, the total power loss P of the power supply device 1 can be minimized by setting the discharge current ratio α to 1.0. D When the discharge current I of power supply device 1 L When the current is 250A, the total power loss P of power supply device 1 can be minimized by setting the discharge current ratio α to 0. DWhen the discharge current I of power supply device 1 L When the current is 300A, the total power loss P of power supply device 1 can be minimized by setting the discharge current ratio α to 0.15. D In other words, in order to minimize the total power loss P of power supply device 1 during discharge... D It is necessary to consider the discharge current I of power supply device 1. L Set the discharge current ratio α.

[0051] Although a detailed description of the example is omitted, the power loss P during charging of main power unit 2 is... DM The power loss P during charging of the auxiliary power supply unit 3 gradually increases with the increase of the charging current of the main power supply unit 2. In contrast, the power loss P during charging of the auxiliary power supply unit 3 is relatively small. DS The power loss of the power supply unit 1 during charging increases irregularly or decreases as the charging current of the auxiliary power supply unit 3 increases. D The 'minimized charging current ratio α' is based on the charging current I of power supply device 1. L 'And changes. Although not shown, the total power loss P of power supply device 1 during charging is...' D The profile of the curve with α as the vertical axis and the charging current ratio α as the horizontal axis is based on the charging current I of power supply device 1. L 'And change. Therefore, in order to make the total power loss P of power supply device 1 during charging...' D Minimization requires considering the charging current I of power supply device 1. L 'Set the charging current ratio α'.

[0052] Therefore, in order to maximize the total power loss P during the discharge of power supply device 1 D minimize, Figure 2 The current control unit 103 shown is based on the discharge current I of the power supply device 1. L The discharge current ratio α is set by adjusting the output current of the voltage conversion unit 32. This is to minimize the total power loss P of the power supply unit 1 during charging. D The current control unit 103 determines the charging current I of the power supply unit 1 based on the current I. L 'The charging current ratio α is set by adjusting the input current of the voltage conversion unit 32'.

[0053] When the ratio of the input current of the main power supply unit 2 to the input current of the auxiliary power supply unit 3 is 1:0, the charging current ratio α' satisfies α' = 1.0. When the ratio of the input current of the main power supply unit 2 to the input current of the auxiliary power supply unit 3 is 0:1, α' = 0.1. When the ratio of the input current of the main power supply unit 2 to the input current of the auxiliary power supply unit 3 is 1:1, the charging current ratio α' satisfies α' = 0.5.

[0054] Figure 8 This is a flowchart illustrating the discharge control performed by the control device 100. When the power supply device 1 is set to discharge mode, the process shown in this flowchart is initiated, and the process proceeds to step S1.

[0055] In step S1, the battery state analysis unit 101 acquires the measured value of the output current of the main power supply unit 2 transmitted from the current sensor 4, the measured value of the output current of the auxiliary power supply unit 3 transmitted from the current sensor 5, and the discharge current I from the power supply unit 1 to the load L transmitted from the current sensor 6. L The measured values ​​and the measured values ​​of the inter-terminal voltage of the main power supply unit 2 transmitted from the voltage sensor 7.

[0056] Next, in step S2, based on the measured values ​​of current and voltage obtained in step S1, the battery state analysis unit 101 estimates the internal resistance r of the main secondary battery 21. m and power supply voltage V m And the conversion efficiency η of the voltage conversion unit 32.

[0057] Next, in step S3, based on the internal resistance r of the main secondary battery 21 estimated by the battery state analysis unit 101 in step S2, m and power supply voltage V m Based on the conversion efficiency η of the voltage conversion unit 32, the mapping generation unit 102 updates the discharge current ratio mapping.

[0058] Next, in step S4, the current control unit 103 determines whether the currently set discharge current ratio α is appropriate. Specifically, the current control unit 103 obtains the discharge current I corresponding to the current sensor 6 measured from the discharge current ratio mapping updated in step S3. L The total power loss P of power supply device 1 D The minimum value, and the total power loss P corresponding to power supply device 1. D The discharge current ratio α is then determined. The current control unit 103 compares the discharge current ratio α obtained from the discharge current ratio map with the currently set discharge current ratio α to determine whether the difference between the two is within a predetermined range. When a positive determination is made in step S4, the process ends; when a negative determination is made in step S4, the process proceeds to step S5. In step S4, instead of determining whether the difference between the discharge current ratio α obtained from the discharge current ratio map and the currently set discharge current ratio α is within a predetermined range, it can be determined whether the two are consistent.

[0059] In step S5, the current control unit 103 adjusts the output current of the voltage conversion unit 32 (such as a DC / DC converter) so that the currently set discharge current ratio α is consistent with the discharge current ratio α obtained in step S4. As described above, the process ends.

[0060] Figure 9 This is a flowchart illustrating the charging control performed by the control device 100. When the power supply device 1 is set to charging mode, the process shown in this flowchart is initiated and proceeds to step S11.

[0061] In step S11, the battery state analysis unit 101 acquires the measured value of the input current of the main power supply unit 2 transmitted from the current sensor 4, the measured value of the input current of the auxiliary power supply unit 3 transmitted from the current sensor 5, and the charging current I from the load L to the power supply device 1 transmitted from the current sensor 6. L The measured value of ' and the measured value of the inter-terminal voltage of the main secondary battery 21 transmitted from the voltage sensor 7.

[0062] Next, in step S12, based on the measured values ​​of current and voltage obtained in step S11, the battery state analysis unit 101 estimates the internal resistance r of the main secondary battery 21. m and power supply voltage V m And the conversion efficiency η' of the voltage conversion unit 32.

[0063] Next, in step S13, based on the internal resistance r of the main secondary battery 21 estimated by the battery state analysis unit 101 in step S12, m and power supply voltage V m Based on the conversion efficiency η' of the voltage conversion unit 32, the mapping generation unit 102 updates the charging current ratio mapping.

[0064] Next, in step S14, the current control unit 103 determines whether the currently set charging current ratio α' is appropriate. Specifically, the current control unit 103 obtains the charging current I corresponding to the current sensor 6 measured from the discharge current ratio mapping updated in step S13. L The total power loss P of power supply device 1 D The minimum value of ' and the total power loss P corresponding to power supply device 1. DThe charging current ratio α' is then determined. The current control unit 103 compares the charging current ratio α' obtained from the charging current ratio map with the currently set charging current ratio α', and determines whether the difference between the two is within a predetermined range. When a positive determination is made in step S14, the process ends; when a negative determination is made in step S14, the process proceeds to step S15. In step S14, instead of determining whether the difference between the charging current ratio α' obtained from the charging current ratio map and the currently set charging current ratio α' is within a predetermined range, it is determined whether the two are consistent.

[0065] In step S15, the current control unit 103 adjusts the input current of the voltage conversion unit 32 (such as a DC / DC converter) so that the currently set charging current ratio α' is consistent with the charging current ratio α' obtained in step S4. As described above, the process ends.

[0066] As described above, the control device 100 according to this embodiment has a discharge current ratio mapping diagram, which indicates the discharge current I from the power supply device 1 to the load L. L The discharge current ratio α, which is the ratio of the output current of the main power supply unit 2 to the output current of the auxiliary power supply unit 3, and the total power loss P of the power supply unit 1 during discharge. D The relationship between them. Control device 100 acquires the discharge current I from power supply device 1 to load L. L The measured value is obtained from the discharge current ratio mapping diagram and compared with the acquired discharge current I. L The measured value and the total power loss P of power supply unit 1 during discharge. D The minimum discharge current ratio α corresponds to the output current from the voltage conversion unit 32 to the load L, thereby achieving the obtained discharge current ratio α. Therefore, the power loss of the power supply unit 1, which includes a main power supply unit 2 and an auxiliary power supply unit 3, can be minimized during discharge. Since the power loss of the power supply unit 1 can be suppressed and the efficiency during discharge can be improved, the increase in heat generated by the power supply unit 1 can be suppressed, thus eliminating the need for a stronger cooling mechanism to suppress the temperature rise of the power supply unit 1.

[0067] Based on the measured current values ​​obtained from current sensors 4, 5, and 6, and the measured inter-terminal voltage of the main secondary battery 21 obtained from voltage sensor 7, the control device 100 of this embodiment estimates the battery state (internal resistance r of the main secondary battery 21) of the main power supply unit 2 and the auxiliary power supply unit 3. m and power supply voltage V m(e.g., the conversion efficiency η of the voltage conversion unit 32). Then, the control device 100 updates the discharge current ratio mapping based on the estimated battery state of the main power supply unit 2 and the auxiliary power supply unit 3. Therefore, for each combination of conditions such as the state of charge (SOC) of the main secondary battery 21 or the auxiliary secondary battery 31, battery temperature, and current value, the optimal conditions for the discharge current ratio α can be obtained, and discharge control with low loss can always be achieved.

[0068] Furthermore, the control device 100 according to this embodiment has a charging current ratio mapping diagram, which indicates the charging current I from the load (power generation unit) L to the power supply device 1. L The charging current ratio α', which is the ratio of the input current of the main power supply unit 2 to the input current of the auxiliary power supply unit 3, and the total power loss P of the power supply unit 1 during charging. D The relationship between ' and '. Control device 100 acquires the charging current I from the load (generator unit) L to the power supply device to the power supply device 1. L The measured value of ' is obtained from the charging current ratio mapping diagram and the acquired charging current I. L The measured value and the total power loss P of power supply device 1 during charging. D The minimum charging current ratio α' is corresponding to the input current from the load (power generation unit) L to the voltage conversion unit 32, thereby achieving the obtained charging current ratio α'. Therefore, the power loss of the power supply unit 1, which includes a main power supply unit 2 and an auxiliary power supply unit 3, can be minimized during charging. Since the power loss of the power supply unit 1 can be suppressed and the efficiency during charging can be improved, the increase in heat generated by the power supply unit 1 can be suppressed, thus making a stronger cooling mechanism for suppressing the temperature rise of the power supply unit 1 unnecessary.

[0069] Based on the measured current values ​​obtained from current sensors 4, 5, and 6, and the measured inter-terminal voltage of the main secondary battery 21 obtained from voltage sensor 7, the control device 100 of this embodiment estimates the battery state (internal resistance r of the main secondary battery 21) of the main power supply unit 2 and the auxiliary power supply unit 3. m and power supply voltage V m (e.g., the conversion efficiency η' of the voltage conversion unit 32). Then, the control device 100 updates the charging current ratio mapping based on the estimated battery state of the main power supply unit 2 and the auxiliary power supply unit 3. Therefore, for each combination of conditions such as the SOC of the main secondary battery 21 and the auxiliary secondary battery 31, the battery temperature, and the current value, the optimal conditions for the charging current ratio α can be obtained, and charging control with low loss can always be achieved.

[0070] Although the present disclosure has been described above based on embodiments, the present disclosure is not limited to the above embodiments, and the above embodiments may be modified or appropriately combined with known or public techniques without departing from the scope of the present disclosure.

[0071] For example, in the above embodiment, the discharge current ratio α is set by adjusting the output current of the auxiliary power supply unit 3 by the voltage conversion unit 32 (such as a DC / DC converter), but it can also be set by adjusting the output current of the auxiliary power supply unit 3 by another current adjustment mechanism. In the above embodiment, the charging current ratio α' is set by adjusting the input current of the auxiliary power supply unit 3 by the voltage conversion unit 32 (such as a DC / DC converter), but it can also be set by adjusting the input current of the auxiliary power supply unit 3 by another current adjustment mechanism.

[0072] Calculate the total power loss P of power supply device 1. D P D Each of the methods described in the above embodiments is not limited to the methods described in the above embodiments, and may be appropriately selected according to the circuit configuration of the power supply device 1. In the above embodiments, the battery state (internal resistance r) of the main secondary battery 21 is estimated in the battery state analysis process. m and power supply voltage V m The conversion efficiency η of the voltage conversion unit 32 can be estimated, but the battery state (internal resistance, power supply voltage, etc.) of the secondary battery 31 can be estimated.

[0073] In the above embodiments, this disclosure is described by way of example using a power supply device 1 including a main power supply unit 2 and a secondary power supply unit 3. However, this disclosure can also be applied to power supply devices including three or more power supply units. In this case, relational information indicating the relationship between the discharge current, discharge current ratio, and power loss of the three or more power supply units can be provided in advance. A specific discharge current ratio of the three or more power supply units can be obtained from the relational information. Under this discharge current ratio, the power loss of the power supply device corresponding to the obtained discharge current measurement value is minimized. Furthermore, the discharge current ratio of the three or more power supply units can be adjusted to the discharge current ratio obtained from the relational information. Additionally, relational information indicating the relationship between the charging current, charging current ratio, and power loss of the three or more power supply units can be provided in advance. A specific charging current ratio of the three or more power supply units can be obtained from the relational information. Under this charging current ratio, the power loss of the power supply device corresponding to the obtained charging current measurement value is minimized. Furthermore, the charging current ratio of the three or more power supply units can be adjusted to the charging current ratio obtained from the relational information.

[0074] Hereinafter, [1] through [8], the features of embodiments of the power control device, power supply device and power control method according to the present disclosure are briefly summarized.

[0075] [1] A power control device (100) is configured to control the charging and discharging of a power supply device (1), the power supply device (1) including a plurality of power supply units (2, 3) connected in parallel to a load (L) and a power generation unit (L).

[0076] Among them, the power control device (100)

[0077] It has an indication of the discharge current (I) flowing from the power supply (1) to the load (L). L The ratio of the output current of multiple power supply units (2, 3) to the discharge current ratio and the power loss (P) of the power supply device (1) are also considered. D Relationship information between the relationships between )

[0078] Obtain the discharge current (I) flowing from the power supply (1) to the load (L). L The measured value of )

[0079] The discharge current ratio (α) is obtained from the relational information. Under this discharge current ratio (α), the discharge current (I) flowing from the power supply device (1) to the load (L) is compared with the obtained discharge current (I). L The power loss (P) of the power supply device (1) corresponding to the measured value. D Minimize, and

[0080] Adjust the discharge current ratio (α) set to the power control device (100) to match the discharge current ratio (α) obtained from the relational information.

[0081] [2] The power control device (100) according to [1] above also includes:

[0082] Among them, the power control device (1)

[0083] Estimate the state of battery of at least one of the secondary batteries (21, 31) included in the plurality of power supply units (2, 3), and

[0084] Update the relationship information based on the estimated battery state.

[0085] [3] A power control device (100) is configured to control the charging and discharging of a power supply device (1), the power supply device (1) including a plurality of power supply units (2, 3) connected in parallel to a load (L) and a power generation unit (L).

[0086] Among them, the power control device (100)

[0087] It has an indication of the charging current (I) flowing from the generator unit (L) to the power supply unit (1). LThe relationship information is the relationship between the ratio of the input current of multiple power supply units (2, 3) to the charging current ratio (α') and the power loss (PD') of the power supply device (1).

[0088] Obtain the charging current (I) flowing from the power generation unit (L) to the power supply device (1). L The measured value of ')

[0089] The charging current ratio (α) is obtained from the relational information. Under this charging current ratio (α), the charging current (I) flowing from the power generation unit (L) to the power supply device (1) is compared with the obtained charging current (I). L The power loss (PD) of the power supply device (1) corresponding to the measured value is minimized, and

[0090] Adjust the charging current ratio (α) set to the power control device (100) to match the charging and discharging current ratio (α) obtained from the relationship information.

[0091] [4] The power control device (100) according to [3] above also includes:

[0092] Among them, the power control device (100)

[0093] Estimate the state of battery of at least one of the secondary batteries (21, 31) in a plurality of power supply units (2, 3), and

[0094] Update the relationship information based on the estimated battery state.

[0095] [5] The power control device (100) according to any one of [1] to [4],

[0096] At least one of the multiple power supply units (2,3) includes a secondary battery (31) and a voltage conversion unit (32) configured to convert the input / output voltage of the secondary battery.

[0097] [6] A power supply device (1), comprising:

[0098] Multiple power supply units (2,3) are connected in parallel to the load (L) and the generator unit (L); and

[0099] According to any one of [1] to [4] above, the power control device (100) is configured to control the charging and discharging of multiple power supply units (2, 3).

[0100] [7] A power control method for charging and discharging a power supply device (1) controlled by a computer, the power supply device (1) comprising multiple power supply units (2, 3) connected in parallel to a load (L) and a power generation unit (L), the power control method comprising:

[0101] Provides indication of the discharge current (I) flowing from the power supply (1) to the load (L). L The ratio of the output current of multiple power supply units (2, 3) to the discharge current ratio (α') and the power loss of the power supply device (1) (P) are also considered. D Relationship information between the relationships between )

[0102] Obtain the discharge current (I) flowing from the power supply (1) to the load (L). L The measured value of )

[0103] The discharge current ratio (α) is obtained from the relational information. Under this discharge current ratio (α), the discharge current (I) flowing from the power supply device (1) to the load (L) is compared with the obtained discharge current (I). L The power loss (P) of the power supply device (1) corresponding to the measured value. D Minimize, and

[0104] Adjust the discharge current ratio (α) set to the power supply device (1) to match the discharge current ratio (α) obtained from the relational information.

[0105] [8] A power control method for charging and discharging a power supply device (1) controlled by a computer, the power supply device (1) comprising multiple power supply units (2, 3) connected in parallel to a load (L) and a power generation unit (L), the power control method comprising:

[0106] Provides indication of the charging current (I) flowing from the generator unit (L) to the power supply unit (1). L '), which is the ratio of the input current of multiple power supply units (2, 3) to the charging current ratio (α') and the power loss of the power supply device (1) (P). D Relationship information between ')

[0107] Obtain the charging current (I) flowing from the power generation unit (L) to the power supply device (1). L The measured value of ')

[0108] The charging current ratio (α') is obtained from the relational information. Under this discharging current ratio (α'), it is compared with the obtained charging current (I) flowing from the power generation unit (L) to the power supply device (1). L The power loss (P) of the power supply device (1) corresponding to the measured value. D Minimize, and

[0109] Adjust the charging current ratio (α') set to the power supply device (1) to match the charging current ratio (α') obtained from the relational information.

Claims

1. A power control device configured to control the charging and discharging of a power supply unit, the power supply unit comprising a plurality of power supply units connected in parallel to a load and a power generation unit. in, The power control device It contains relational information indicating the relationship between the discharge current flowing from the power supply to the load, the discharge current ratio as a ratio of the output currents of the plurality of power supply units, and the power loss of the power supply. Obtain a measurement of the discharge current flowing from the power supply to the load. The discharge current ratio is obtained from the relationship information, and at this discharge current ratio, the power loss of the power supply device corresponding to the measured value of the discharge current flowing from the power supply device to the load is minimized, and Adjust the discharge current ratio set to the power control device to match the discharge current ratio obtained from the relationship information. At least one of the plurality of power supply units includes a capacitor and a voltage conversion unit configured to convert the input / output voltage of the capacitor.

2. The power control device according to claim 1, in, The power control device Estimate the state of battery of at least one of the secondary batteries included in multiple power supply units, and The relationship information is updated based on the estimated battery state.

3. A power control device configured to control the charging and discharging of a power supply unit, said power supply unit comprising a plurality of power supply units connected in parallel to a load and a power generation unit. in, The power control device It contains relational information indicating the relationship between the charging current flowing from the power generation unit to the power supply device, the ratio of the charging currents to the input currents of the plurality of power supply units, and the power loss of the power supply device. Obtain a measurement of the charging current flowing from the power generation unit to the power supply device. The charging current ratio is obtained from the relationship information, and at this charging current ratio, the power loss of the power supply device corresponding to the measured value of the charging current flowing from the power generation unit to the power supply device is minimized, and Adjust the charging current ratio set to the power control device to match the charging current ratio obtained from the relationship information. At least one of the plurality of power supply units includes a capacitor and a voltage conversion unit configured to convert the input / output voltage of the capacitor.

4. The power control device according to claim 3, in, The power control device Estimate the state of battery of at least one of the secondary batteries included in multiple power supply units, and The relationship information is updated based on the estimated battery state.

5. A power supply device, comprising: Multiple power supply units are connected in parallel to the load and the power generation unit; as well as The power control device according to any one of claims 1 to 4 is configured to control the charging and discharging of the plurality of power supply units.

6. A power control method for charging and discharging a power supply device using a computer, the power supply device comprising multiple power supply units connected in parallel to a load and a power generation unit, the power control method comprising: Provides relational information indicating the relationship between the discharge current flowing from the power supply to the load, the discharge current ratio as a ratio of the output currents of the plurality of power supply units, and the power loss of the power supply. Obtain a measurement of the discharge current flowing from the power supply to the load; The discharge current ratio is obtained from the relationship information, and the power loss of the power supply device is minimized at the discharge current ratio corresponding to the measured value of the discharge current flowing from the power supply device to the load. as well as Adjust the discharge current ratio set to the power supply device to match the discharge current ratio obtained from the relationship information. At least one of the plurality of power supply units includes a capacitor and a voltage conversion unit configured to convert the input / output voltage of the capacitor.

7. A power control method for charging and discharging a power supply device using a computer, the power supply device comprising multiple power supply units connected in parallel to a load and a power generation unit, the power control method comprising: Provides relational information indicating the relationship between the charging current flowing from the power generation unit to the power supply device, the ratio of the charging current to the input current of the plurality of power supply units, and the power loss of the power supply device. Obtain a measurement of the charging current flowing from the power generation unit to the power supply device. The charging current ratio is obtained from the relationship information, and at this charging current ratio, the power loss of the power supply device corresponding to the measured value of the charging current flowing from the power generation unit to the power supply device is minimized, and Adjust the charging current ratio set to the power supply device to match the charging current ratio obtained from the relationship information. At least one of the plurality of power supply units includes a capacitor and a voltage conversion unit configured to convert the input / output voltage of the capacitor.

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