JP2012230819A - Power recovery apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power recovery apparatus which can recover the residual power of a battery as much as possible.SOLUTION: A control unit 3 selects a prescribed input power supply by referring to a connection candidate table in memory 4 and connects it to a DC-DC converter 2. Next, it compares the power supply capability of the input power supply and a charging or a loading condition, and, if the power supply capability is larger than the charging or the loading condition, starts charging by the input power supply. Then, by entering the voltage or power of the input power supply after a prescribed time has elapsed, the control unit determines whether or not to stop charging depending on a charging stop condition stored in the memory 4, and, if determined to stop charging, refers to a recovery time table or an approximate relational expression stored in the memory 4 to determine a recovery time of the input power supply, and, after placing the input power supply into a dormant state for recovery purpose, refers to the connection candidate table of the memory 4 to search for the next connectable input power supply.

Description

  The present invention relates to a power recovery apparatus, for example, a power recovery apparatus that recovers as much residual power as possible in a used primary battery or secondary battery.

  Unlike conventional analog devices, digital devices do not operate at all when the power supply voltage falls below the value required by the digital circuit. For example, in the case of an AA battery, the digital device does not operate when the output voltage falls below 1.3V. In such a case, the dry battery is often discarded as used.

  However, even batteries discarded in this way have residual power. In recent years, since digital devices such as mobile phones and portable music players have exploded, it is extremely difficult to recover the remaining power of used batteries from the viewpoint of saving energy and reducing environmental impact. is important.

  The present invention provides a power recovery device that can recover as much of the remaining power of a battery as possible.

  The present invention utilizes the characteristic that the output recovers by resting the battery (hereinafter referred to as “battery output recoverability”) in order to recover as much residual power as possible from the used battery. This battery output recoverability is that the internal resistance increases and the output voltage decreases due to chemical reaction while the battery is discharged, whereas the internal resistance decreases and the output voltage increases when the battery discharge is stopped. It depends.

The power recovery device according to one aspect of the present invention includes:
A DC-DC converter that boosts or steps down an input DC voltage and outputs the DC voltage;
A plurality of input power sources including a battery having residual power can be connected, and a switch unit that electrically connects any of the input power sources to the DC-DC converter by switching,
A connection candidate table that includes information on whether or not the connected input power supply has been restored and whether or not to dispose of it can be determined, and for driving the charging conditions or electrical load of the secondary battery to be charged A load condition, a charge stop condition for stopping charging by the input power supply, and a recovery time table or approximate relational expression for obtaining a recovery time of the battery until the charge condition or the load condition is satisfied after the charge is stopped And a memory storing a disposal standard table for determining whether or not to discard the battery,
A predetermined input power source is selected from connectable input power sources with reference to the memory connection candidate table, the switch unit is controlled to connect the input power source to the DC-DC converter, and then the input power source The power supply capacity of the input power supply is compared with the charge condition or load condition of the memory, and when the power supply capacity of the input power supply is greater than the charge condition or load condition, charging by the input power supply is started. When the power supply capacity of the input power source does not satisfy the charging condition or the load condition, it is determined whether or not the input power source can be discarded by referring to the memory disposal standard table. A voltage of the input power supply after the lapse of time is input, and it is determined whether or not the input power supply needs to be stopped based on a charge stop condition stored in the memory. When it is determined that charging should be stopped, the recovery time of the input power source is determined with reference to the recovery time table stored in the memory or the approximate relational expression, and the input power source is put into a sleep state for recovery. And a control unit that searches for a next connectable input power source with reference to the memory connection candidate table.

  The recovery time table or approximate relational expression of the input power source stored in the memory includes the elapsed time until the voltage drop start point at which the voltage drop rate is greater than a predetermined value, the voltage at the elapsed time, the charging condition, and the charging Comprising a table or an approximate relational expression that determines the correspondence between the correction value according to the storage state of the secondary battery or the load condition and the recovery time for each type of battery, and the control unit is configured for the input power supply that is being charged. The elapsed time until the voltage drop start point actually measured and the voltage at the elapsed time are input, and the recovery time of the input power source can be determined from the recovery time table or the approximate relational expression.

  Further, the recovery time table or approximate relational expression of the input power source stored in the memory is an elapsed time until a charging stop point at which voltage or power drops below a reference value determined based on the charging condition or load condition, and It consists of a table or an approximate relational expression that defines the correspondence between the charging condition and the correction value according to the storage state or load condition of the secondary battery to be charged and the recovery time for each type of battery, and the control unit performs charging. It is possible to input the elapsed time until the charging stop point actually measured for the input power supply being performed, and determine the recovery time of the input power supply from the recovery time table or the approximate relational expression.

  In addition, the connection candidate table immediately updates a battery whose recovery time has passed to a recovered state, and the control unit selects an input power source to be connected to the DC-DC converter from the recovered input power source. To be able to.

  The charging stop condition of the input power source stored in the memory is a voltage drop starting point at which the voltage drop rate is greater than a predetermined value, or a voltage or electric power from a reference value determined based on the charge condition or load condition. The reduced charging stop point is used as a condition for stopping charging, and the control unit inputs the voltage or voltage and current of the input power source that is charging every predetermined time, and the input power source is the voltage drop start point or the charging point. When the stop point elapses in time, charging of the input power supply can be stopped.

  In addition, the discard standard table includes (a) that the total recovery time has reached the upper limit, (b) a predetermined number of recovery periods, and (c) an initial period in the discharge period for the input power source to be determined. The output voltage is lower than a predetermined value, (d) the duration of the initial output voltage in the discharge period is shorter than the predetermined value, (e) the recovery time is longer than the predetermined value, (f) the output voltage in the discharge period The drop rate is greater than a predetermined value, or (g) the recovered power does not reach a predetermined value as a disposal criterion, and the control unit excludes the input power source connected to the DC-DC converter for the first time. It is possible to determine that the input power source corresponding to any one or a combination of the discard criteria should be discarded and to output a discard signal.

  Further, the input power source includes a complementary power source, and the control unit is configured such that all connectable input power sources do not satisfy the connection candidate condition, and the power stored in the secondary battery to be charged is stored in the storage capacity. When not reached, the switch unit is controlled to connect the complementary power source to a DC-DC converter, and the secondary battery can be charged by the complementary power source.

A power recovery device according to another aspect of the present invention includes:
A DC-DC converter that boosts or steps down an input DC voltage and outputs the DC voltage;
A plurality of input power sources including a battery having residual power can be connected, and a switch unit that electrically connects any of the input power sources to the DC-DC converter by switching,
A connection candidate table that includes information on whether or not the connected input power supply has been restored and whether or not to dispose of it can be determined, and for driving the charging conditions or electrical load of the secondary battery to be charged A memory storing a load condition, a charge stop condition for stopping charging by the input power supply, and a disposal criterion table for determining whether or not to discard the battery;
A predetermined input power source is selected from connectable input power sources with reference to the memory connection candidate table, the switch unit is controlled to connect the input power source to the DC-DC converter, and then the input power source The power supply capacity of the input power supply is compared with the charge condition or load condition of the memory, and when the power supply capacity of the input power supply is greater than the charge condition or load condition, charging by the input power supply is started. When the power supply capacity of the input power source does not satisfy the charging condition or the load condition, it is determined whether or not the input power source can be discarded by referring to the memory disposal standard table. A voltage of the input power supply after the lapse of time is input, and it is determined whether or not the input power supply needs to be stopped based on a charge stop condition stored in the memory. If it is determined that charging should be stopped, the input power supply is put into a sleep state for recovery, and the next connectable input power supply is searched based on a predetermined order with reference to the connection candidate table of the memory. And a control unit.

  The charging stop condition of the input power source stored in the memory is that the voltage or power is lower than a voltage drop starting point at which the voltage drop rate is greater than a predetermined value, or a reference value determined based on the charging condition or load condition. The charge stop point is set as a charge stop condition, and the control unit inputs the voltage or voltage and current of the input power supply that is charging every predetermined time, and the input power supply is the voltage drop start point or the charge stop point. When time elapses, charging of the input power supply can be stopped.

  In addition, the discard standard table includes (a) that the total recovery time has reached the upper limit, (b) a predetermined number of recovery periods, and (c) an initial period in the discharge period for the input power source to be determined. The output voltage is lower than a predetermined value, (d) the duration of the initial output voltage in the discharge period is shorter than the predetermined value, (e) the recovery time is longer than the predetermined value, (f) the output voltage in the discharge period The drop rate is greater than a predetermined value, or (g) the recovered power does not reach a predetermined value as a disposal criterion, and the control unit excludes the input power source connected to the DC-DC converter for the first time. It is possible to determine that the input power source corresponding to any one or a combination of the discard criteria should be discarded and to output a discard signal.

  Further, the input power source includes a complementary power source, and the control unit is configured such that all connectable input power sources do not satisfy the connection candidate condition, and the power stored in the secondary battery to be charged is stored in the storage capacity. When not reached, the switch unit is controlled to connect the complementary power source to a DC-DC converter, and the secondary battery can be charged by the complementary power source.

  In the power recovery apparatus according to one aspect of the present invention, the control unit starts charging the input power source whose power supply capacity is larger than the charging condition or the load condition, and inputs the voltage of the input power source after a predetermined time has elapsed. If it is determined whether or not charging by the input power supply should be stopped according to the charging stop condition stored in the memory, and if it is determined that charging by the input power supply should be stopped, the recovery time table or approximate relational expression stored in the memory The recovery time of the input power supply is determined with reference to the above, the input power supply is put into a resting state for recovery, and the next connectable input power supply is searched with reference to the memory connection candidate table.

  Thus, according to the power recovery device according to one aspect of the present invention, the input power source satisfying the charging condition or the load condition is started to be charged and stopped when the charging capacity of the input power source is reduced, while other use is performed. A possible input power source is searched and charged, and when the former input power source is recovered by a pause, the input power source is searched again and charged. As described above, according to the present invention, the power of the battery can be repeatedly recovered by resting for charging, and during that time, it can be charged by another recovered battery, so that the remaining power of the battery can be used without waste. It is possible to charge a secondary battery and drive an electric load well.

  Especially in the invention that determines the recovery time when it is suspended, it is sufficient for the expected charging of the battery whose recovery time varies depending on the type of battery, the degree of consumption of the battery, or the charging condition or the load condition. The battery until it reaches a certain state is determined in advance, and the battery whose recovery time has passed can be used immediately for charging, thereby enabling highly efficient power recovery.

It is a figure showing a schematic structure of an electric power recovery device concerning a 1st embodiment of the present invention. It is a graph which shows an example of the voltage change of an input battery. It is a flowchart which shows an example of operation | movement of the electric power recovery apparatus which concerns on the 1st Embodiment of this invention. It is an example of the connection candidate table | surface which determines the presence or absence of the input power supply which satisfy | fills the connection candidate conditions. It is the graph which showed notionally the relationship between the voltage drop of a battery, and time, Comprising: It is explanatory drawing for demonstrating the method of determining the conditions of the charge stop by this invention. It is a flowchart which shows an example of operation | movement of the electric power recovery apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows schematic structure of the electric power recovery apparatus which concerns on the 3rd Embodiment of this invention.

  Hereinafter, three embodiments according to the present invention will be described with reference to the drawings. In addition, in each figure, the component which has an equivalent function is attached | subjected the same code | symbol, and detailed description of the component of the same code | symbol is not repeated.

(First embodiment)
FIG. 1 is a configuration diagram of a power recovery apparatus according to the first embodiment of the present invention. The power recovery apparatus 10 according to the present embodiment includes a switch unit 1, a DC-DC converter 2, a control unit 3, and a memory 4.

  The input power source 20 is connected to the input of the power recovery apparatus 10 (switch unit 1), and the secondary battery 30 is connected to the output of the power recovery apparatus 10 (DC-DC converter 2). The secondary battery 30 may be connected as an input power source for another device, or may be taken out and used alone. In the example illustrated in FIG. 1, five input power sources 20 a, 20 b, 20 c, 20 d, and 20 e are connected to the power recovery apparatus 10.

  Input power sources 20a, 20b, 20c, 20d, and 20e include batteries that have been used without limitation but have reduced voltage but still have residual power. In addition, the input power supply can include a complementary power source that complementarily charges the secondary battery 30 when the secondary battery 30 cannot be charged with the battery. This embodiment will be described with an example including a complementary power source.

  The switch unit 1 has a plurality of input terminals that can be connected to an input power supply, and an output terminal connected to the input terminal of the DC-DC converter 2. The switch unit 1 connects one of the input power sources connected to the input terminal to the DC-DC converter 2. Each input terminal of the switch unit 1 may be connected to a battery socket that stores a predetermined type of battery such as a single battery, a single battery, or a mercury battery. Since the specific input power source has a battery socket for a specific type of battery, each input terminal of the switch unit 1 is associated with the type of the input power source, and the power recovery device 10 identifies the type of the input power source. In other words, it is possible to set in advance a criterion for determining battery consumption based on the voltage and discharge characteristics that serve as a reference for each type of battery.

  The DC-DC converter 2 boosts or steps down the input DC voltage and outputs it. The DC-DC converter 2 may have a feedback control mechanism for outputting a predetermined voltage. This feedback control mechanism feeds back the output voltage of the DC-DC converter 2 and reflects it in the step-up / step-down control.

  The control unit 3 has a function of controlling the operation of the entire apparatus, and in particular, selects an input power source to be connected to the DC-DC converter 2 from among input power sources that satisfy the connection candidate conditions. A function of controlling the switch unit 1 so as to connect the DC converter 2; a function of determining the stop of charging of the input power supply during charging; a function of determining a recovery time for each of the input power supplies; A function for determining whether or not the input power source can be discarded, and a function for determining and controlling whether or not to perform charging with the complementary power source. Here, the complementary power source is a complementary power source for charging the secondary battery 30 when all other input batteries do not satisfy the connection candidate conditions and cannot be used. By using this supplementary power source, when the remaining power of the input battery is insufficient to charge up to the storage capacity of the secondary battery 30, or the secondary battery 30 needs to be charged quickly and wait for the recovery period to elapse. It is possible to deal with cases where there is no such thing. As a supplementary power source, for example, a charged secondary battery or a power adapter (input AC 100 V, output DC 12 V) can be used. In the latter case, the input terminal for the complementary power source of the switch unit 1 is connected not to the battery socket but to the socket for the power adapter.

  The control unit 3 measures the output voltage of the DC-DC converter 2 and stores the measured value in the memory 4. The output voltage of the DC-DC converter 2 is a device (not shown) that is separate from the apparatus of the present invention. The control unit 3 of the present invention may receive measurement information from the device.

  The memory 4 is written and read by the control unit 3. As information stored in the memory 4, a recovery time table showing an elapsed time until a voltage drop start point, which will be described later, a voltage at the elapsed time (or an elapsed time until the charging stop point), and a recovery time corresponding to them, A power supply capacity of each input power source (such as a measured value of the output voltage of the DC-DC converter 2), a condition for stopping charging, a recovery time, a disposal standard table having reference values for determining whether or not to discard the battery, and There is information related to the connection candidate table in FIG.

  Next, the details of the time change of the discharge and recovery voltage of an input power supply will be described. FIG. 2 shows an example of a voltage change of discharge and recovery of an input power supply (referred to as input power supply 20a). In FIG. 2, discharge periods I and II indicate periods in which the input power source 20 a is connected to the DC-DC converter 2 and is discharged, and in a recovery period I, the input power source 20 a is not connected to the DC-DC converter 2. , Shows a period of no discharge.

  As shown in FIG. 2, during the discharge period I, the voltage of the input power supply 20a continues to drop from the initial voltage V0 and drops to the voltage V1 at time t1. Since the voltage V1 is the minimum voltage required for charging the secondary battery 30, the control unit 3 selects another input power source from the connection candidates and controls the switch unit 1 so as to switch to the selected input power source.

  When charging is stopped, the input power supply 20a enters a recovery period due to a chemical reaction inside the battery, and the voltage gradually recovers from V1 to V2 due to the battery output recoverability. When the recovery period (recovery time) T elapses, the input power source 20a becomes one of the connection candidates again. The recovery time varies depending on the chemical reaction used by the input power source.

  Next, operation | movement of the electric power collection | recovery apparatus 10 which concerns on 1st Embodiment is demonstrated along the flowchart of FIG.

(1) The power recovery by the power recovery apparatus 10 of the present embodiment starts by first mounting a battery having a residual power that has decreased in voltage as a result of being used (step S10). It is assumed that a complementary power source is included in the input power source.

(2) When a battery is attached to the battery socket, the control unit 3 selects one of the input power supplies that satisfy the connection candidate condition and connects it to the DC-DC converter 2 (step S11).

  Although there are various methods for selecting an input power source that satisfies the connection candidate condition, the example of this embodiment is selected using the connection candidate table shown in FIG.

  The connection candidate table in FIG. 4 includes fields of “input power supply”, “not connected”, “recovery time”, and “discard”. The “input power source” field indicates an input power source connected to the power recovery apparatus 10. The complementary power source is not included in the connection candidate input power source of this connection candidate table. In the “unconnected” field, “1” is stored when the input power source is not connected to the DC-DC converter 2, and “0” is stored when the input power source is connected. In the “recovery time” field, “1” is stored when the input power supply has been waiting for the recovery time after being disconnected from the DC-DC converter 2, and “0” when the recovery time has not yet elapsed. Is stored. That is, the battery after the recovery time has elapsed is immediately updated to the recovered state. The “discard” field stores “1” when the input power source does not satisfy the discard criterion, and stores “0” when the input power source satisfies the discard criterion. As shown in FIG. 4A, when the connection is not established, “0” is stored in the “recovery time” field, and “1” is stored in the “discard” field.

  FIG. 4A shows an initial state in which none of the input power sources connected to the power recovery apparatus 10 has been connected to the DC-DC converter 2 yet. In this case, all input power sources are connection candidates. When all the input power sources are not yet connected to the DC-DC converter 2, selection may be made in the order of the input power sources 20a, 20b,.

  FIG. 4B shows a case where the input power source 20b is switched to another input power source after several cycles. In the example of FIG. 4B, the input power sources 20a and 20c do not become connection candidates because the recovery time has not elapsed. The next input power supply 20d does not become a connection candidate because it has reached the disposal standard. Therefore, in this case, since only the input power source 20e satisfies the connection candidate condition, the switch unit 1 is connected to the DC-DC converter 2.

  Thus, the control unit 3 checks the connection candidate table as shown in FIG. 4 in a predetermined order for the input power source connected to the battery socket, and first selects the input power source satisfying the connection candidate condition. Connect to the DC-DC converter 2.

(3) Next, the device of the present application measures the power supply capability of the input power source connected to the DC-DC converter 2 in order to determine whether or not the secondary battery 30 can be charged (step). S12).

  The power supply capability of the input power supply connected to the DC-DC converter 2 can be measured, for example, by measuring the output voltage of the DC-DC converter 2. Further, the output voltage V and the output current I may be measured to calculate the power P (= I · V).

(4) Next, it is determined whether or not the power supply capability of the input power source measured in step S12 satisfies a charging condition determined according to the secondary battery 30 (step S13).

  This is because the power supply capability for charging differs depending on the type of the secondary battery 30. For example, when the secondary battery 30 is a lithium ion battery, the output voltage of the DC-DC converter 2 is 3.7 V or more. Is the charging condition. Although the voltage can be stepped up / down by the DC-DC converter 2, a predetermined amount of current is also required for charging, and therefore the charging condition of the secondary battery 30 is not satisfied by the DC-DC converter 2. In some cases, it is necessary to determine whether or not the charging condition is satisfied. The charging condition of the secondary battery 30 is stored in the memory 4. In this step S13, when an electrical load such as a motor is connected to the output of the power recovery apparatus 10 instead of a secondary battery, the power supply capability of the input power supply is a load for driving the electrical load. Determine whether the condition is met.

  If the power supply capacity exceeds the charging condition (or load condition), the process proceeds to charging, and conversely if the power supply capacity falls below the charging condition, the process proceeds to the determination of whether or not the battery can be discarded. The determination of whether or not the battery can be discarded will be described later.

(5) The charging process when the power supply capacity exceeds the charging condition will be described below.

  In step S13, when it is determined that the power supply capability of the input power source exceeds the charging condition of the secondary battery 30 (step S13; Y), charging of the secondary battery 30 is started by the input power source ( Step S14).

  After starting the charging of the secondary battery 30 by the input power source, the control unit 3 inputs a voltage after a predetermined time of the input power source and determines whether or not the charging of the input power source should be stopped (step) S15).

  Here, a method for determining whether to stop charging will be described with reference to FIG. The graph of FIG. 5 conceptually shows the relationship between the voltage drop of the battery and time when the secondary battery 30 is charged by the battery. In general, after starting charging, the battery input power source maintains the voltage almost flat for a certain period of time, the voltage drops greatly from a certain point in time, and when it drops to a certain voltage, the degree of voltage drop decreases, Thereafter, the voltage gradually decreases.

In this embodiment, when the charging of the secondary battery 30 by the input power supply is started, the time (t ₀ , t ₁ , t ₂ ,...) and the corresponding voltages (V ₀ , V ₁ , V ₂ ,...) are measured.

Since the measurement interval (Δt) is known, the voltage drop rate (| ΔV / Δt |) can be calculated by taking the voltage difference (ΔV). Thereby, the point at which the voltage drop rate (| ΔV / Δt |) increases rapidly can be detected as a “voltage drop start point” as shown in FIG. When the voltage drop start point is detected, it is determined that charging by the input power source should be stopped (step S15; Y). The time and voltage at the voltage drop start point (in the example of FIG. 5, (t ₄ , V ₄ )) are recorded in the memory 4 to determine the recovery time of the battery.

  Further, instead of deciding to stop charging based on the voltage drop start point, the charging condition of the secondary battery 30 (voltage in the case of FIG. 5) or a voltage higher than the voltage of the charging condition by a predetermined voltage (collectively charging them) When the voltage of the input power source is lower than the reference value of the charging condition of the secondary battery, compared to the “reference value of the condition.” It can also be determined that charging should be stopped (step S15; Y). The reference value of the charging condition or load condition may be electric power instead of voltage.

  If it is determined in step S15 that charging by the input power source should be stopped (step S15; Y), the process proceeds to the determination of the recovery time, and conversely, if it is determined that charging need not be stopped (step) In step S15; N), the process returns to step S13 to compare with the charging condition and continue charging.

(6) When it is determined that charging by the input power supply should be stopped, the recovery time of the input power supply is determined as follows, and the input power supply is rested and recovered.

The voltage drop start point (t ₄ , V ₄ ) shown in FIG. 5 is largely related to the remaining power of the input power supply, the charging condition and the storage state of the secondary battery to be charged. Here, t ₄ is the time elapsed from the start of charging, V ₄ is the voltage at the elapsed time t _4. The storage state indicates how much power is stored in the secondary battery with respect to the storage capacity of the secondary battery.

That is, the voltage V ₀ immediately after the start of charging has an upper limit depending on the type of the battery to be charged, and the magnitude changes in accordance with the amount of remaining power within the range. The voltage V _{4 at} the voltage drop start point that approximates the voltage V ₀ immediately after the start of charging is also related to the amount of remaining power. The smaller the value of the voltage V _4, determines a longer recovery time.

Further, as shown in FIG. 5, the elapsed time t ₄ from the charging start voltage descent shows a time to keep the voltage V ₀ which immediately after the start of charging. The elapsed time t ₄ also changes depending on the amount of remaining power of the input cell. The shorter the elapsed time t ₄ from the charging start voltage descent short, to determine a longer recovery time.

Further, the voltage drop start point (t ₄ , V ₄ ) is also affected by the charging condition and the storage state of the secondary battery 30 to be charged. In other words, when the secondary battery 30 has a small capacity or is almost charged and the secondary battery 30 is charged with low power P, the elapsed time from the start of charging at the voltage drop start point t ₄ becomes longer. For this reason, it is preferable to determine the recovery time in consideration of the charging condition of the secondary battery 30 and the correction value according to the storage state.

The memory 4 includes a voltage drop start point (t ₄ , V ₄ ) and a secondary battery charging condition for each battery type (single, single,..., Mercury battery, lithium ion battery, manganese battery, etc.). In addition, a recovery time table or an approximate relational expression of the recovery time indicating the correspondence between the correction value according to the storage state and the recovery time is stored. By referring to the recovery time table or the approximate relational expression, the battery recovery time is determined from the actually measured voltage drop start point (t ₄ , V ₄ ) (step S16). The recovery time table or the approximate relational expression of the recovery time can be obtained from experience or experimental values.

On the other hand, when it is determined to stop charging as compared with the “reference value of the charging condition of the secondary battery”, the remaining power of the battery and the charging of the secondary battery are also determined during the time t _{5 ′} until reaching the charging stop point. The length varies depending on the condition and the storage state.

Also in this case, the memory 4 stores the elapsed time t5 _′ up to the charging stop point and the secondary battery for each type of battery (single, single,..., Mercury battery, lithium ion battery, manganese battery, etc.). Store the recovery time table or approximate relational expression showing the correspondence between the correction value and the recovery time depending on the charging condition and power storage state, and refer to this recovery time table or approximate relational expression to actually measure the charge The battery recovery time is determined from the elapsed time t5 _' up to the stop point (step S16).

  As described above, by determining the recovery time for each input power supply, useless standby time can be omitted, and the recovered battery can be used immediately for charging, and efficient charging can be performed.

  After determining the recovery time, the input power supply that has stopped charging starts recovery (step S17).

(7) Next, the control unit 3 refers to the connection candidate table (FIG. 4) of the memory 4 described above and searches whether there is an input power source that is a connection candidate (step S18).

The presence or absence of an input power supply that satisfies the connection candidate condition can be determined by using a discriminant for each input power supply. Equation (1) can be used as the discriminant. If D = 1, the connection candidate condition is satisfied, and if D = 0, the connection candidate condition is not satisfied.
D = (A + B) · C (1)
Here, A: the value of the unconnected field, B: the value of the recovery time field, and C: the value of the discard field. Note that the discriminant of equation (2) may be used instead of equation (1).
D = A + (BC) (2)
If there is an input power source that is a connection candidate (step S18; Y), the process returns to step S11, the input power source of the connection candidate is connected to the DC-DC converter 2, and a secondary battery is subsequently connected by the input power source. Charge the battery.

  If there is no input power source that is a connection candidate (step S18; N), it is determined whether or not charging is complete (step S19).

  If it is determined that charging is complete, that is, if the secondary battery 30 has reached a capacity that can be stored, the power recovery process by the device of the present application is terminated (step S21). Whether or not the power of the secondary battery 30 has reached the storage capacity may be measured by a known device (not shown), and the information may be input to the control unit 3. The accumulated power may be measured.

  When it is determined that charging is not completed, that is, when it is determined that the electric power stored in the secondary battery 30 has not reached the storage capacity (step S19; N), the control unit 3 controls the switch unit 1. The supplementary power source is connected to the DC-DC converter 2, and the secondary battery 30 is charged with the supplementary power source until the storage capacity is full, and then the power recovery process by the device of the present application is terminated (step S21).

  Of course, instead of automatically charging with a complementary power source, an alarm that does not have a connection candidate input power source may be output to prompt the user to replace the battery.

(8) Finally, in step 13, in determining whether the power supply capability of the input power source connected to the DC-DC converter 2 is greater than the charging condition, the power supply capability of the input power source satisfies the charging condition. A case where it is determined that there is not (step S13; N) will be described.

  When it is determined that the power supply capability of the input power source does not satisfy the charging condition of the secondary battery (step S13; N), it is determined whether or not the battery should be discarded (step S23).

  Whether or not the battery should be discarded is determined with reference to the disposal criteria, which can be set using various events.

  For example, (a) the sum of recovery times has reached the upper limit, (b) a predetermined number of recovery periods have passed, (c) the initial output voltage in the discharge period is lower than a predetermined value, (d) discharge The duration of the initial output voltage in the discharge period is shorter than a predetermined value, (e) the recovery time is longer than the predetermined value, and (f) the rate of decrease in output voltage (| ΔV / Δt |) in the discharge period is a predetermined value. Or (g) an event such as the fact that the power collected by the secondary battery 30 does not reach a predetermined value can be used as a disposal standard. Any combination of these events may be used as the disposal standard.

  In addition, it is preferable to determine the above-mentioned disposal standards such as the upper limit of the total recovery time of the event (a) for each type of battery on the input side.

  Strictly speaking, the above-described disposal standard is affected not only by the type of battery on the input side but also by the storage state of the secondary battery to be charged. For this reason, the memory 4 stores, for each type of battery on the input side, a disposal standard table storing the standard values of the above events (a) to (g) in consideration of correction values according to the storage state of the secondary battery. It is preferable to leave it.

  When it is determined that the input power source connected to the DC-DC converter 2 does not satisfy the charging condition of the secondary battery (step S13; N), the control unit 3 discards the memory 4 Referring to the standard table, determine whether the connected input power source is one of the disposal standards or a combination of multiple disposal standards. A discard signal is output for (step S24).

  Regarding the input power source connected to the DC-DC converter 2 for the first time (input power source connected for the first time), the number of recovery periods of event (b) is 0. In this case, as an exception, events (c) to (g) Even if it corresponds to each of the reference values, the recovery process (step S16), that is, the hibernation state is applied.

  If the connected input power supply has already recovered several cycles and does not correspond to any of the disposal standards (a) to (g), the battery recovery process in step S16 and subsequent steps is performed.

  As described above, in the present embodiment, the remaining power is repeatedly collected from the input power source and used for charging the secondary battery 30 in consideration of the battery output recoverability. Thereby, according to this embodiment, the residual electric power of an input battery can be collect | recovered as much as possible. As a result, for example, the remaining power of a battery such as a dry battery discarded from a general household can be efficiently recovered.

  Note that the power recovery apparatus 10 may further include a current adjustment circuit that outputs an output current from the DC-DC converter 2 with a desired current value. This current adjustment circuit is configured using, for example, a current mirror circuit. By providing the current adjustment circuit, the power recovery device 10 can output a current corresponding to the secondary battery 30. For example, when the secondary battery 30 is a lithium ion battery, the charging efficiency can be increased by setting the output current of the power recovery device 10 to 50 mA. Furthermore, according to the power recovery device provided with both the feedback control mechanism and the current adjustment circuit of the DC-DC converter 2 described above, the secondary battery that is subjected to severe conditions such as a lithium-ion battery can be charged safely. It can fully handle charging.

  The power recovery apparatus 10 may further include means (such as an LED lamp) for informing the user that the input power source has reached the disposal standard and prompting the user to replace the input power source.

(Second Embodiment)
Next, a power recovery apparatus according to the second embodiment of the present invention will be described. In the second embodiment, a combination of scanning input power sources that are connection candidates in a certain order without determining the recovery time of batteries that have stopped charging, determination of stopping charging, and determination of power supply capability Thus, the processing of the apparatus is simplified.

  The configuration of the power recovery apparatus according to the second embodiment is the same as that shown in FIG. FIG. 6 shows a processing flow according to the second embodiment. The processing flow in FIG. 6 is the same as the processing flow in FIG. 3 except that steps S16 and S17 in FIG. 3 are not provided.

  According to the second embodiment, when a battery is installed in the battery socket, the control unit 3 selects one of the input power sources that satisfy the connection candidate condition and connects it to the DC-DC converter 2 ( Step S11).

  Next, the power supply capability of the input power source connected to the DC-DC converter 2 is measured (step S12). In this measurement, similarly to the first embodiment, the output voltage of the DC-DC converter 2, or the output voltage V and the output current I, or the power P (= I · V) is measured.

  Next, it is determined whether or not the power supply capability of the input power source measured in step S12 satisfies a charging condition determined according to the secondary battery 30 (step S13).

  In step S13, when it is determined that the power supply capability of the input power source exceeds the charging condition of the secondary battery 30 (step S13; Y), charging of the secondary battery 30 is started by the input power source ( Step S14).

  Subsequently, it is determined whether or not charging of the input power source should be stopped after a predetermined time has elapsed (step S15). The method for determining whether to stop charging is the same as in the first embodiment.

  If it is determined that charging by the input power source should be stopped (step S15; Y), the process proceeds to a process for determining whether or not there is an input power source that is a connection candidate. When it determines with it being good (step S15; N), it returns to step S13, compares with charging conditions, and continues charging.

  In the present embodiment, whether or not there is an input power source that is a connection candidate is determined by scanning the connectable input power source and excluding the input power source that is determined to be discarded, and the input power source that can still be used in a predetermined order. Is connected to the DC-DC converter 2 and the power supply capability of the input power source is measured (step S12) and compared with the charging condition of the secondary battery 30 (step S13). If it is larger than the condition, charging is started (step S14), and if it is smaller, it is judged to be discarded (step S23), and the next usable input power source is searched.

  When all the input power sources are determined to be discarded and when all the input power sources are scanned a predetermined number of times or more, it is determined whether or not charging is complete in step S19.

  According to the second embodiment, without determining the recovery time of each battery, the available batteries are searched in order, and the process is simplified by a simple process of charging if possible. Can do.

(Third embodiment)
Next, a power recovery apparatus according to the third embodiment of the present invention will be described. FIG. 7 shows a schematic configuration of the power recovery apparatus 100 according to the third embodiment. As shown in FIG. 7, the power recovery device 100 includes a plurality of power recovery devices 10A, 10B, and 10C, and a rectifying element 110 connected to the output terminals of the power recovery devices 10A, 10B, and 10C.

  The power recovery devices 10A, 10B, and 10C have the same configuration as the power recovery device 10 according to the first and second embodiments, but each DC-DC converter 2 has a feedback control mechanism, and the output voltage is Both are equal.

  The rectifying element 110 is provided between the output end of the power recovery apparatus 10A, 10B or 10C and the output end of the power recovery apparatus 100. As shown in FIG. 7, the rectifying element 110 is provided such that a forward current flows from the power recovery device 10 </ b> A, 10 </ b> B or 10 </ b> C to the output terminal of the power recovery device 100. That is, one end of the rectifying element 110 is connected to the output end of the power recovery device 10A, 10B, or 10C, and the direction in which the power from the power recovery device 10A, 10B, or 10C is supplied is the forward direction.

With the above configuration, the direct currents I ₁ , I ₂ , and I ₃ output from the respective power recovery devices 10A, 10B, and 10C are added together to become a current I (= I ₁ + I ₂ + I ₃ ), and the power recovery device 100 Is output from the output terminal.

  Therefore, according to the third embodiment, the remaining power of the input power supply 20 can be recovered as much as possible as in the first and second embodiments, and the output current can be increased. . Thereby, for example, the charging time of the secondary battery 30 can be shortened.

  The power recovery apparatus 100 may further include a current adjustment circuit 120 that adjusts the summed current I to a desired current value. According to such a configuration, a current corresponding to the electrical load connected to the output terminal of the power recovery apparatus 100 can be output. Thereby, for example, the charging efficiency of the secondary battery 30 can be increased.

  As mentioned above, although three embodiment which concerns on this invention was described, the aspect of this invention is not limited to embodiment mentioned above.

  For example, in the above embodiment, the secondary battery is connected to the output terminal of the power recovery device. However, what is connected to the output of the power recovery devices 10 and 100 is not limited to this, and other electrical devices are connected. It may be a load (for example, a motor, a light bulb, etc.).

  Based on the above description, those skilled in the art may be able to conceive additional effects and various modifications of the present invention, but the aspects of the present invention are not limited to the above-described embodiments. Various additions, modifications, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Switch part 2 DC / DC converter 3 Control part 4 Memory 10, 10A, 10B, 10C, 100 Power recovery device 20, 20a, 20b, 20c, 20d, 20e Input power supply 30 Secondary battery 110 Rectifier 120 Current adjustment circuit

Claims (12)

A DC-DC converter that boosts or steps down an input DC voltage and outputs the DC voltage;
A plurality of input power sources including a battery having residual power can be connected, and a switch unit that electrically connects any of the input power sources to the DC-DC converter by switching,
A connection candidate table that includes information on whether or not the connected input power supply has been restored and whether or not to dispose of it can be determined, and for driving the charging conditions or electrical load of the secondary battery to be charged A load condition, a charge stop condition for stopping charging by the input power supply, and a recovery time table or approximate relational expression for obtaining a recovery time of the battery until the charge condition or the load condition is satisfied after the charge is stopped And a memory storing a disposal standard table for determining whether or not to discard the battery,
A predetermined input power source is selected from connectable input power sources with reference to the memory connection candidate table, the switch unit is controlled to connect the input power source to the DC-DC converter, and then the input power source The power supply capacity of the input power supply is compared with the charge condition or load condition of the memory, and when the power supply capacity of the input power supply is greater than the charge condition or load condition, charging by the input power supply is started. When the power supply capacity of the input power source does not satisfy the charging condition or the load condition, it is determined whether or not the input power source can be discarded by referring to the memory disposal standard table. Determining whether or not to stop charging by the input power source according to the charging stop condition stored in the memory by inputting the voltage or power of the input power source after elapse of time, When it is determined that charging by the power source should be stopped, the recovery time of the input power source is determined by referring to the recovery time table or approximate relational expression stored in the memory to recover the input power source. A control unit that is put into a dormant state and searches for a next connectable input power source by referring to the connection candidate table of the memory;
A power recovery apparatus comprising: The recovery time table or approximate relational expression of the input power source stored in the memory includes the elapsed time until the voltage drop start point at which the voltage drop rate is greater than a predetermined value, the voltage at the elapsed time, the charging condition, and the charging Consisting of a table or approximate relational expression that defines the correspondence between the correction value according to the storage state or load condition of the secondary battery to be restored and the recovery time for each battery type,
The control unit inputs an elapsed time until the voltage drop start point actually measured for the input power source that is being charged and a voltage at the elapsed time, and the recovery time of the input power source from the recovery time table or the approximate relational expression. The power recovery device according to claim 1, wherein: The recovery time table or approximate relational expression of the input power source stored in the memory includes an elapsed time until a charging stop point at which voltage or power drops below a reference value determined based on the charging condition or load condition, and the charging It consists of a table or an approximate relational expression that defines the correspondence between the recovery value and the correction value depending on the condition and the storage state or load condition of the charged secondary battery for each type of battery,
The control unit inputs an elapsed time until a charging stop point actually measured for an input power supply that is charging, and determines a recovery time of the input power supply from the recovery time table or an approximate relational expression. The power recovery apparatus according to claim 1.   The connection candidate table immediately updates a battery whose recovery time has elapsed to a recovered state, and the control unit selects an input power source to be connected to the DC-DC converter from the recovered input power source. The power recovery apparatus according to any one of claims 1 to 3. The charging stop condition of the input power source stored in the memory is that the voltage or power is lower than a voltage drop starting point at which the voltage drop rate is greater than a predetermined value, or a reference value determined based on the charging condition or load condition. Set the charging stop point as the condition for stopping charging,
The control unit inputs the voltage or voltage and current of the input power supply that is charging every predetermined time, and when the input power supply has passed the voltage drop start point or the charge stop point in time, The power recovery apparatus according to claim 1, wherein charging of the input power supply is stopped. For the input power source to be judged, the discard criteria table indicates that (a) the total recovery time has reached the upper limit, (b) a predetermined number of recovery periods have passed, (c) the initial output voltage in the discharge period Is lower than a predetermined value, (d) the duration of the initial output voltage in the discharge period is shorter than the predetermined value, (e) the recovery time is longer than the predetermined value, and (f) the output voltage is lowered in the discharge period. The disposal standard is that the speed is greater than the predetermined value, or (g) that the collected power does not reach the predetermined value.
The control unit determines that the input power source corresponding to one or a plurality of combinations of the discard criteria should be discarded, except for the input power source connected to the DC-DC converter for the first time, and outputs a discard signal. The power recovery device according to any one of claims 1 to 5. The input power source includes a complementary power source,
The control unit controls the switch unit when all connectable input power sources do not satisfy the connection candidate conditions and the power stored in the secondary battery to be charged does not reach the storage capacity. The power recovery device according to claim 1, wherein the complementary power source is connected to a DC-DC converter, and the secondary battery is charged by the complementary power source. A DC-DC converter that boosts or steps down an input DC voltage and outputs the DC voltage;
A plurality of input power sources including a battery having residual power can be connected, and a switch unit that electrically connects any of the input power sources to the DC-DC converter by switching,
A connection candidate table that includes information on whether or not the connected input power supply has been restored and whether or not to dispose of it can be determined, and for driving the charging conditions or electrical load of the secondary battery to be charged A memory storing a load condition, a charge stop condition for stopping charging by the input power supply, and a disposal criterion table for determining whether or not to discard the battery;
A predetermined input power source is selected from connectable input power sources with reference to the memory connection candidate table, the switch unit is controlled to connect the input power source to the DC-DC converter, and then the input power source The power supply capacity of the input power supply is compared with the charge condition or load condition of the memory, and when the power supply capacity of the input power supply is greater than the charge condition or load condition, charging by the input power supply is started. When the power supply capacity of the input power source does not satisfy the charging condition or the load condition, it is determined whether or not the input power source can be discarded by referring to the memory disposal standard table. A voltage of the input power supply after the lapse of time is input, and it is determined whether or not the input power supply needs to be stopped based on a charge stop condition stored in the memory. If it is determined that charging should be stopped, the input power supply is put into a sleep state for recovery, and the next connectable input power supply is searched based on a predetermined order with reference to the connection candidate table of the memory. And the control unit,
A power recovery apparatus comprising: The charging stop condition of the input power source stored in the memory is that the voltage or power is lower than a voltage drop starting point at which the voltage drop rate is greater than a predetermined value, or a reference value determined based on the charging condition or load condition. Set the charging stop point as the condition for stopping charging,
The control unit inputs the voltage or voltage and current of the input power supply that is charging every predetermined time, and when the input power supply has passed the voltage drop start point or the charge stop point in time, The power recovery apparatus according to claim 8, wherein charging of the input power supply is stopped. For the input power source to be judged, the discard criteria table indicates that (a) the total recovery time has reached the upper limit, (b) a predetermined number of recovery periods have passed, (c) the initial output voltage in the discharge period Is lower than a predetermined value, (d) the duration of the initial output voltage in the discharge period is shorter than the predetermined value, (e) the recovery time is longer than the predetermined value, and (f) the output voltage is lowered in the discharge period. The disposal standard is that the speed is greater than the predetermined value, or (g) that the collected power does not reach the predetermined value.
The control unit determines that the input power source corresponding to one or a plurality of combinations of the discard criteria should be discarded, except for the input power source connected to the DC-DC converter for the first time, and outputs a discard signal. The power recovery device according to claim 8 or 9. The input power source includes a complementary power source,
The control unit controls the switch unit when all connectable input power sources do not satisfy the connection candidate conditions and the power stored in the secondary battery to be charged does not reach the storage capacity. The power recovery apparatus according to claim 8, wherein the complementary power source is connected to a DC-DC converter, and the secondary battery is charged by the complementary power source.   A plurality of the power recovery devices according to any one of claims 1 to 11, wherein one end is connected to an output end of the plurality of power recovery devices, and a direction in which power is supplied from the plurality of power recovery devices is forward. A power recovery apparatus comprising the rectifying element.

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