JP2015042067A - Device for charge/discharge control of electrical storage battery having bidirectional isolated dc-dc converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for charge/discharge control of an electrical storage battery having a bidirectional isolated DC-DC converter which can appropriately perform charge/discharge even when a voltage of the electrical storage battery drops with discharge.SOLUTION: The device for charge/discharge control of an electrical storage battery having the bidirectional isolated DC-DC converter for charging/discharging the electrical storage battery is provided with a step-down DC-DC converter connected in parallel with the bidirectional isolated DC-DC converter so as to add to a charging voltage when the electrical storage battery is charged.

Description

  The present invention relates to a storage battery charge / discharge control device including a bidirectional insulated DC-DC converter that can appropriately perform charge / discharge of a storage battery, and a wireless system including the same.

  A power conversion device that converts DC power is generally called a DC / DC converter, and a non-insulated type and an insulated type are known. The insulated DC / DC converter includes, for example, a transformer (hereinafter referred to as a transformer as appropriate), a first converter connected to the primary side of the transformer and converting DC power into AC power, and a secondary side of the transformer. And a second converter connected to convert AC power into DC power.

  In addition, there is known a bidirectional insulated DC / DC converter capable of transmitting DC power from the primary side to the secondary side of the transformer and transmitting DC power from the secondary side of the transformer to the primary side.

  In the bidirectional insulated DC / DC converter, a switching circuit (bridge circuit) is provided on both the primary side and the secondary side of the transformer, the timing for driving the switching circuit provided on the primary side of the transformer, By changing the timing to drive the switching circuit provided on the secondary side, it is possible to transmit DC power from the primary side to the secondary side or DC power from the secondary side to the primary side. is there.

  Further, by using a bidirectional insulated DC / DC converter, for example, a secondary battery such as a lithium ion battery provided on the secondary side is charged as necessary, and the secondary battery is charged with a direct current. A charging device that can extract electric power to the primary side as needed can be realized.

  In addition, as described above, the invention relates to a power conversion device that converts DC power and a charging device including the device, and includes a power conversion device whose output voltage is variable over a wide voltage range, and the device. The primary side input / output terminals (T11, T12) and the secondary side input for DC power input / output are provided for the purpose of providing a charging device that can efficiently charge over a wide voltage range. A high-frequency transformer (22) provided between output terminals (T21, T22) and a first converter provided between the primary-side input / output terminal and the high-frequency transformer for converting DC power and AC power. A power conversion circuit (21) and a second power conversion circuit (23) provided between the secondary input / output terminal and the high-frequency transformer for converting DC power and AC power; To convert The conversion device (13, 50) includes a replacement circuit (25a, 25b) capable of switching the arrangement of the primary side and the secondary side of the high-frequency transformer with respect to the primary side input / output end and the secondary side input / output end. A technical idea of a power conversion device is disclosed in Patent Document 1 below.

  Further, based on such a configuration, Patent Document 1 discloses a replacement circuit capable of switching the arrangement of the primary side and the secondary side of the high-frequency transformer with respect to the primary side input / output end and the secondary side input / output end of the power converter. Therefore, the output voltage can be made variable over a wide voltage range. Thus, it is described that the charging device has an effect that it can be efficiently charged over a wide voltage range.

  Moreover, FIG. 9 is a figure explaining the structure of the conventional power supply device provided with a backup storage battery. As shown in FIG. 9, conventionally, a charging power supply unit for charging a storage battery in a normal state without a power failure and a discharging power supply unit for discharging and backing up from the storage battery when a power failure occurs are separately and independently provided. Each configuration is known.

JP 2013-021867 A

  A conventional storage battery charge / discharge control device using a bi-directional insulated DC-DC converter is known to reduce the voltage at the start of discharge of the storage battery (hereinafter referred to as full charge voltage as appropriate) and discharge. The voltage difference from the voltage of the storage battery at the end of the discharge (hereinafter referred to as the discharge end voltage as appropriate) could not be dealt with.

  For example, a transformer winding of a bidirectional insulated DC-DC converter can output a desired output voltage to be supplied to a load even when the voltage of the storage battery is relatively low near the discharge end voltage when the storage battery is discharged. When the line ratio is set, the relatively low voltage value is supplied to the storage battery when the storage battery is charged, and it is extremely difficult to fully charge the storage battery to the full charge voltage.

  On the other hand, the transformer winding ratio of the bidirectional insulated DC-DC converter is set so that a relatively high voltage value is supplied to the storage battery so that it can be fully charged to the full charge voltage when the storage battery is charged. Then, when the voltage of the battery for storage is relatively low near the discharge end voltage when discharging the battery for storage, it becomes extremely difficult to output a desired output voltage to be supplied to the load due to insufficient voltage.

  The present invention has been made in view of the above-described problems, and includes a bidirectional insulation type DC-DC converter that can appropriately perform charging and discharging even when there is a voltage drop in a storage battery accompanying discharge. It is an object of the present invention to realize a charge / discharge control device and a wireless system for a storage battery.

  The charge / discharge control device for a storage battery according to the present invention is a charge / discharge control device for a storage battery including a bidirectional insulation type DC-DC converter that charges and discharges the storage battery. A step-down DC-DC converter having a bidirectional insulation type DC-DC converter and an input side connected in parallel and an output side connected in series so as to increase the charging voltage from the direction insulation type DC-DC converter. Features.

  Even if there is a voltage drop in the storage battery due to discharge, it is possible to realize a storage battery charge / discharge control device and a wireless system including a bidirectional insulation type DC-DC converter capable of appropriately performing charge / discharge.

It is a figure explaining the structure outline | summary of a radio | wireless system provided with the charging / discharging control apparatus of the battery for electrical storage of 1st embodiment. It is a figure explaining the more detailed structure concept of the charging / discharging control apparatus of the battery for electrical storage shown in FIG. 1 at the time of charge. It is a figure explaining the more detailed structure concept of the charging / discharging control apparatus of the battery for electrical storage shown in FIG. 1 at the time of discharge. It is a figure explaining the electrical characteristic of the charging / discharging control apparatus of the electrical storage battery at the time of charge to the electrical storage battery, and at the time of discharge of an electrical storage battery, (a) shows the electrical characteristic at the time of charge, (b ) Is a diagram showing electrical characteristics during discharge. It is a flowchart explaining the part relevant to this invention of the operating condition of the charging / discharging control apparatus of the battery for electrical storage. It is a figure explaining so that the structural concept at the time of charge of the charging / discharging control apparatus of an electrical storage battery may become still easier to understand. It is a figure explaining the structure outline | summary of the radio | wireless system of a positive voltage electric power feeding system provided with the charging / discharging control apparatus of the battery for electrical storage of 2nd embodiment. It is a figure explaining the structure outline | summary of the radio | wireless system of a negative voltage electric power feeding system provided with the charging / discharging control apparatus of the battery for electrical storage of 3rd embodiment. It is a figure explaining the structure outline | summary of the conventional power supply device provided with a backup storage battery.

  The charge / discharge control device for a storage battery exemplified in this embodiment includes a bidirectional insulated DC-DC converter having both a discharge converter and a storage converter. And at the time of discharge, the secondary side switching element of the bidirectional insulation type DC-DC converter is driven, and the power of the secondary battery (storage battery) such as a lithium ion battery connected to the secondary side, The voltage is converted to a voltage suitable for the load (for example, 48V) by an insulating transformer and then supplied to the load.

  In addition, it is known that the voltage of the storage battery gradually decreases as the discharge process proceeds. Therefore, not only when the voltage of the battery for storage is at the full charge voltage (for example, 54 V) at the start of discharge, but also until the discharge end voltage (for example, 38 V) at which the voltage drops to a certain extent and then stops discharge. The winding ratio (for example, 48:38) between the primary side and the secondary side of the insulated transformer is determined so that the processing can be continued.

  On the other hand, at the time of charging in which the commercial power supply has no trouble (that is, when it is normal) and power is supplied from the commercial power supply to the load and charging from the commercial power supply to the storage battery is performed, the bidirectional insulated DC− The switching element on the primary side of the DC converter is driven to generate a charging voltage.

  Here, the winding ratio between the primary side and the secondary side of the insulation transformer included in the bidirectional insulation type DC-DC converter is set so that the discharge end voltage can be boosted to the load supply voltage during discharge as described above. Therefore, at the time of charging in the opposite direction, the bidirectional insulated DC-DC converter connected to the load supply voltage (for example, 48V) generates only the charging voltage corresponding to the discharge end voltage (for example, 38V). Can not.

  For this reason, the charging / discharging control device for the storage battery exemplified in the present embodiment is further required to charge the storage battery to a full charge voltage (for example, 54V), and a raised voltage (54V−38V = 16V). A step-down DC-DC converter is generated.

  The step-down DC-DC converter has a wiring configuration in which the bidirectional output type DC-DC converter and the input are connected in parallel while the outputs are connected in series so that both output voltages are added. Further, the step-down DC-DC converter is connected to the power supply line from the commercial power source to the load in the same manner as the bidirectional insulation type DC-DC converter, and is based on the load supply voltage (for example, 48V), and raises the voltage (for example, 16V).

  As a result, even when the voltage of the storage battery drops during discharge, the battery continues to discharge until the specified discharge end voltage and exhibits a long-time backup function, and is charged to the full charge voltage appropriately during charging. It is possible to realize a charge / discharge control device for a storage battery capable of charging a storage battery. Therefore, further detailed description will be given below based on the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating a configuration outline of a wireless system 1000 including a storage battery charge / discharge control device 1500 according to the first embodiment. In FIG. 1, the wireless device 1300 is illustrated as a typical example of the load, but the load may be arbitrary and is not limited to the wireless device 1300. On the other hand, the wireless device 1300 is a representative of an important infrastructure that is strongly required to operate and operate as a means of communication for disaster victims even in an unforeseen situation where a failure occurs in the commercial power supply 1100 or when a natural disaster occurs. This is a typical example.

  As can be understood from FIG. 1, the wireless system 1000 includes a commercial power source 1100 and a power supply unit 1200 that converts power from the commercial power source 1100 into appropriate power corresponding to an input to the wireless device 1300. The power supply unit 1200 may be configured by an AC-DC converter, for example.

  In addition, in the wiring for supplying power from the power supply unit 1200 to the wireless device 1300, when the power supply from the power supply unit 1200 is interrupted, backup power can be supplied instead. Is connected. The storage battery charge / discharge control device 1500 is connected to a storage battery 1400 serving as a backup power source when a failure occurs. The storage battery 1400 has a configuration in which a plurality of secondary batteries such as lithium ion batteries are connected in parallel or / and in series so as to have desired electrical characteristics and capacity corresponding to the power consumption of the wireless device 1300 and the like. Also good.

  In addition, the storage battery charge / discharge control device 1500 converts the power of the storage battery 1400 into power suitable for the wireless device 1300 and supplies it as backup power when a failure occurs. Is provided.

  In addition, the storage battery charge / discharge control device 1500 adds to the charge voltage generated by the bidirectional insulated DC-DC converter 1510 when charging the storage battery 1400 (normal time), and stores the storage battery 1400. A step-down DC-DC converter 1520 for generating a charging voltage for raising the voltage to the full charging voltage. The step-down DC-DC converter 1520 can be non-insulated. The bidirectional insulated DC-DC converter 1510 includes an insulated transformer 1511 in which a bridge circuit (typically a full bridge circuit) is arranged on each of the primary side and the secondary side.

  FIG. 2 is a diagram illustrating a more detailed configuration concept of charge / discharge control device 1500 for the storage battery shown in FIG. 1 during charging. In FIG. 2, the same parts as those in FIG. Further, in FIG. 2, for the sake of convenience of explanation, a storage battery 1400 is also shown.

  As shown in FIG. 2, the bidirectional insulation type DC-DC converter 1510 includes four primary side switching elements 1512 (1), switching elements 1512 (2), switching elements 1512 (3), and switching elements that are driven during charging. An element 1512 (4) is provided.

  As can be understood from FIG. 2, the four switching elements 1512 (1), 1512 (2), 1512 (3), and 1512 (4) form a bridge and are switched at diagonal positions. The element 1512 (1), the switching element 1512 (4), the switching element 1512 (2), and the switching element 1512 (3) are each paired and driven on and off synchronously to supply power to the wireless device 1300. A charging voltage is generated from the voltage of the supply line.

  The four switching elements 1512 (1), switching element 1512 (2), switching element 1512 (3), and switching element 1512 (4) are switched by the charging bridge control circuit 2100 as shown in FIG. 1) The switching element 1512 (4) is set as one set, and the switching element 1512 (2) and the switching element 1512 (3) are set as another set, and the on / off control is performed alternately.

  In FIG. 2, a bidirectional insulated DC-DC converter 1510 includes four switching elements 1512 (1), a switching element 1512 (2), a switching element 1512 (3), and a storage battery of the switching element 1512 (4). An insulating transformer 1511 is provided on the 1400 side. The voltage transmitted from the primary side (commercial power supply 1100 side) to the secondary side (storage battery 1400 side) via the insulated transformer 1511 depends on the winding ratio of the insulated transformer 1511 and is usually used for storage. The voltage value is lower than the fully charged voltage of the battery 1400.

  Further, in order to maintain the dischargeable time of the storage battery 1400 as a relatively long time and maintain the period during which it can function as a backup power source for a relatively long time, even if the voltage of the storage battery 1400 decreases to some extent due to discharge, the storage battery The winding ratio of the insulated transformer 1511 is determined so that it can be used while 1400 power remains.

  That is, it is possible to supply power (for example, 48 V) to the wireless device 1300 until the voltage of the storage battery 1400 reaches the discharge end voltage (for example, 36 V) for stopping the discharge from the fully charged voltage (for example, 54 V). In addition, the winding ratio of the insulating transformer 1511 is set to 48:36, for example.

For this reason, based on a load supply voltage of, for example, 48 V supplied to the primary side of the bidirectional insulated DC-DC converter 1510 during charging, the bidirectional insulated DC-DC converter 1510 is connected to the secondary storage battery 1400. The voltage that can be supplied is generally 36 V (V ₁ in FIG. 2). On the other hand, in order to prepare for the storage battery 1400 to be fully available and to fully exhibit the backup function, it is required to be charged to a full charge voltage (for example, 54 V).

For this reason, the charge / discharge control device 1500 for the storage battery is configured such that the full charge voltage (for example, 54V) of the storage battery 1400 and the bidirectionally insulated DC-DC converter 1510 are on the secondary side based on a load supply voltage of 48V, for example. Is provided with a step-down DC-DC converter 1520 that compensates for a difference (for example, 18 V, V ₂ in FIG. 2) from a voltage (for example, 36 V) that can be supplied.

  The switching element 1521 included in the step-down DC-DC converter 1520 is ON / OFF controlled by the charging bridge control circuit 2100 so as to have a desired raised voltage during charging. For example, when the raised voltage to be generated may be relatively small, the charging bridge control circuit 2100 may reduce the ON period of the switching element 1521 and make the OFF period of the switching element 1521 relatively long. Good.

  Further, for example, when the raised voltage to be generated is relatively large, the charging bridge control circuit 2100 may make the ON period of the switching element 1521 relatively long and the OFF period of the switching element 1521 relatively short.

  Further, as shown in FIG. 2, the switch element 2300 provided at the output terminal of the step-down DC-DC converter 1520 is turned off (opened) by a discharge bridge control circuit 2200 described later during charging. As a result, the output terminal of the step-down DC-DC converter 1520 is connected in series to the output terminal of the bidirectional insulated DC-DC converter 1510, and the generated voltages are added to each other. A sufficient voltage necessary for charging up to the full charge voltage is supplied.

  FIG. 3 is a diagram for explaining a more detailed configuration concept of the storage battery charge / discharge control device 1500 shown in FIG. 1 during discharge. In FIG. 3, the same portions as those in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof is omitted. Further, in FIG. 3, a storage battery 1400 is also shown for convenience of explanation.

  As shown in FIG. 3, the bidirectionally insulated DC-DC converter 1510 includes four secondary-side switching elements 1513 (1), switching elements 1513 (2), switching elements 1513 (3), A switching element 1513 (4) is provided.

  As can be understood from FIG. 3, the four switching elements 1513 (1), the switching element 1513 (2), the switching element 1513 (3), and the switching element 1513 (4) form a bridge. When a power failure occurs, the switching element 1513 (1), the switching element 1513 (4), the switching element 1513 (2), and the switching element 1513 (3) at the diagonal positions are paired, The power is turned on and off in synchronization with each other, and a supply voltage (for example, 48 V) to the wireless device 1300 is generated from the voltage (for example, 54 V to 36 V) of the battery 1400 for power storage.

  The four switching elements 1513 (1), switching element 1513 (2), switching element 1513 (3), and switching element 1513 (4) are switched by the discharge bridge control circuit 2200 by the switching element 1513 (1) and switching element 1513 ( 4) is driven by the signal b in FIG. 3, and the switching element 1513 (2) and the switching element 1513 (3) are driven by the signal a in FIG. The signals “a” and “b” shown in FIG. 3 alternately and exclusively control switching elements corresponding to each other.

  Note that when the storage battery 1400 is discharged, it is not necessary to drive the four switching elements 1512 (1), the switching element 1512 (2), the switching element 1512 (3), the switching element 1512 (4), and the switching element 1521. The charging bridge control circuit 2100 may be stopped or put to sleep.

  For example, as shown in FIG. 3, a blocking unit 2110 that blocks the drive signal of the charging bridge control circuit 2100 during discharging based on an instruction from the discharging bridge control circuit 2200 may be provided. When the blocking unit 2110 is provided, it is not necessary to stop or sleep the charging bridge control circuit 2100, but it is preferable to stop or sleep the charging bridge control circuit 2100 during discharging from the viewpoint of power saving. Since it is generally considered that there is a shortage of power resources in situations where power supply by discharge from the backup power supply is necessary, it can be said that it is desirable to suppress wasteful power consumption as much as possible.

  In FIG. 3, the bidirectional insulated DC-DC converter 1510 includes a wireless device 1300 including four switching elements 1513 (1), a switching element 1513 (2), a switching element 1513 (3), and a switching element 1513 (4). An insulating transformer 1511 is provided on the side. The voltage transmitted from the secondary side (storage battery 1400 side) to the primary side (wireless device 1300 side) via the insulation transformer 1511 depends on the winding ratio of the insulation transformer 1511 and is usually a storage battery. The winding ratio (for example, 48:36) is set so that the voltage required for operation of the wireless device 1300 can be transmitted even at the discharge end voltage of 1400.

  Also, as shown in FIG. 3, the discharge bridge control circuit 2200 turns on (short-circuits) the switch element 2300 provided at the output terminal of the step-down DC-DC converter 1520 during discharge. As a result, the output terminal of the step-down DC-DC converter 1520 is short-circuited to form a return current path for discharge to the storage battery 1400. As shown in FIGS. 2 and 3, the bidirectional insulated DC-DC converter 1510 may be a so-called regenerative converter.

  FIG. 4 is a diagram for explaining the electrical characteristics of the storage battery charge / discharge control device 1500 when the storage battery 1400 is charged and when the storage battery 1400 is discharged. FIG. (B) is a figure which shows the electrical characteristic at the time of discharge.

As shown in FIG. 4A, when charging the storage battery 1400, the charging voltage (V ₁ ) generated by the bidirectional insulated DC-DC converter 1510 based on the load supply voltage and the load supply voltage are used. Then, a voltage ((V ₁ + V ₂ ), for example, 54 V) obtained by adding the charging voltage (V ₂ ) generated by the step-down DC-DC converter 1520 is applied to the storage battery 1400.

  Further, as shown in FIG. 4B, when the storage battery 1400 is discharged, backup can be performed by discharging while the voltage of the storage battery 1400 is between the full charge voltage and the discharge end voltage (<full charge voltage). It becomes. In addition, when the battery 1400 is discharged, even if the voltage of the battery 1400 changes from the full charge voltage to the end-of-discharge voltage, based on the changed voltage of the battery 1400, the bidirectional insulation type DC-DC Converter 1510 can supply a voltage (for example, 48 V) necessary for operation of wireless device 1300.

  FIG. 5 is a flowchart for explaining a portion related to the present invention of the operating state of the charge / discharge control device 1500 for the storage battery. Then, based on each step shown in FIG. 5, the part relevant to this invention of the operating condition of the charging / discharging control apparatus 1500 of an electrical storage battery is demonstrated one by one below.

(Step S510)
The wireless system 1000 determines whether the commercial power supply 1100 and the power supply unit 1200 are normal. For this reason, the wireless system 1000 may include a power supply monitoring unit that determines whether or not desired power is normally supplied to the wireless device 1300. In addition, a typical example of power supply failure due to a large-scale natural disaster or the like seems to be that power supply from the commercial power source 1100 is interrupted, but the wireless device 1300 is also used when the power supply unit 1200 is damaged due to a lightning strike, for example. It is preferable that backup is possible so that the system can be continuously operated.

  If the wireless system 1000 determines that there is no abnormality in the commercial power supply 1100 and the power supply unit 1200, the process proceeds to step S520, unless the wireless system 1000 determines that there is no abnormality in the commercial power supply 1100 and the power supply unit 1200. Then, the process proceeds to step S550.

(Step S520)
The charging bridge control circuit 2100 includes four switching elements 1512 (1), a switching element 1512 (2), a switching element 1512 (3), and a switching element 1512 (4) on the primary side of the bidirectional insulated DC-DC converter 1510. To generate a charging voltage (V ₁ ) of the storage battery 1400.

(Step S530)
The charging bridge control circuit 2100 drives the switching element 1521 of the step-down DC-DC converter 1520 to generate the charging voltage (V ₂ ) of the storage battery 1400. Steps S520 and S530 can be performed simultaneously.

(Step S540)
The switching element 2300 provided at the output terminal of the step-down DC-DC converter 1520 is turned off (opened) by the discharge bridge control circuit 2200, and the charging voltage (V) generated by the bidirectional insulated DC-DC converter 1510 is generated. ₁ ) and the charging voltage (V ₂ ) generated by the step-down DC-DC converter 1520 are added and applied to the storage battery 1400.

  As a result, the storage battery 1400 is sufficiently and sufficiently charged to the full charge voltage. In addition, when there is a rated charge amount or the like of the storage battery 1400, it is not always necessary to fully charge the battery, and the battery 1400 is charged to a charging state or a charging voltage that is an appropriate electrical characteristic of the storage battery 1400 as a backup preparation. And can.

(Step S550)
The discharge bridge control circuit 2200 includes four switching elements 1513 (1), 1513 (2), 1513 (3), and 1513 (4) on the secondary side of the bidirectional insulated DC-DC converter 1510. ) To generate a supply voltage to the wireless device 1300 from the voltage of the storage battery 1400.

(Step S560)
The discharge bridge control circuit 2200 turns on (short-circuits) the switch element 2300 provided at the output terminal of the step-down DC-DC converter 1520 to form a current path that circulates to the storage battery 1400. Steps S550 and S560 can be performed simultaneously.

(Step S570)
Wireless system 1000 determines whether or not the voltage of power storage battery 1400 is equal to or lower than a predetermined discharge end voltage at which discharge should be stopped. For this reason, the wireless system 1000 may include an output voltage monitoring unit of the storage battery 1400.

  When wireless system 1000 determines that the voltage of power storage battery 1400 is equal to or lower than a predetermined discharge end voltage at which discharge should be stopped, the process proceeds to step S580. If wireless system 1000 does not determine that the voltage of power storage battery 1400 is equal to or lower than a predetermined discharge end voltage at which discharge should be stopped, standby in step S570 is continued and backup by discharge is continued.

  Note that the case where the commercial power source 1100 and the like are restored and the normal power supply is resumed during this standby is not shown in FIG. 5, but in this case, the step position of the flowchart shown in FIG. Regardless of this, the backup supply from the storage battery 1400 can be quickly stopped.

(Step S580)
When the voltage of power storage battery 1400 is equal to or lower than a predetermined discharge end voltage at which discharge should be stopped, backup discharge by power storage battery 1400 is terminated. In this case, it may be configured such that the power backup can be continuously performed by switching to the charge / discharge control device for the second power storage battery or / and the second power storage battery. Further, the third power storage battery, the fourth power storage battery,... And a plurality of power storage batteries may be provided, and the backup duration may be longer.

  FIG. 6 is a diagram for explaining the configuration concept during charging of the storage battery charge / discharge control device 1500 so as to make it easier to understand. As can be understood from FIG. 6, the step-down DC-DC converter 1520 is described as a chopper circuit in FIG. 6 so that it can be understood intuitively. The detailed description of FIG. 6 is omitted here because it overlaps with the description of FIG.

(Second embodiment)
FIG. 7 is a diagram for explaining an outline of the configuration of a positive voltage power supply type wireless system 7000 including the storage battery charge / discharge control device 7500 of the second embodiment. In FIG. 7, the wireless device 7300 is illustrated as a typical example of the load, but the load may be arbitrary and is not limited to the wireless device 7300. On the other hand, the wireless device 7300 is a representative of an important infrastructure that is strongly required to operate and operate as a means of communication for disaster victims even in an unexpected situation where a failure occurs in the commercial power supply 7100 or when a natural disaster occurs. This is a typical example.

  As can be understood from FIG. 7, the wireless system 7000 includes a commercial power supply 7100 and a power supply unit 7200 that converts power from the commercial power supply 7100 into appropriate power corresponding to an input to the wireless device 7300. The power supply unit 7200 may be constituted by an AC-DC converter, for example.

  In addition, in the wiring for supplying power from the power supply unit 7200 to the wireless device 7300, when the power supply from the power supply unit 7200 is interrupted, backup power can be supplied instead. (1) is connected.

  The storage battery charge / discharge control device 7500 (1) is connected to a storage battery 7400 serving as a backup power source when a failure occurs. The storage battery 7400 has a configuration in which a plurality of secondary batteries such as lithium ion batteries are connected in parallel or / and in series so as to have desired electrical characteristics and capacity corresponding to the power consumption of the wireless device 7300 and the like. Also good.

  In addition, the storage battery charge / discharge control device 7500 (1) converts the power of the storage battery 7400 into power suitable for the wireless device 7300 and supplies it as backup power when a failure occurs. A DC converter 7510 is provided.

  In addition, the storage battery charge / discharge control device 7500 (1) adds the charge voltage generated by the bidirectional insulated DC-DC converter 7510 when charging the storage battery 7400 (normal time) to store the storage battery 7400. A step-down DC-DC converter 7520 for generating a charging voltage for raising the battery 7400 to a fully charged voltage. The step-down DC-DC converter 7520 can be non-insulated. The bidirectional insulated DC-DC converter 7510 includes an insulated transformer 7511 in which a bridge circuit is arranged on each of the primary side and the secondary side.

  As can be understood from FIG. 7, the wireless system 7000 includes a storage battery charge / discharge control device 7500 (2) connected in parallel with the storage battery charge / discharge control device 7500 (1). In FIG. 7, the storage battery charge / discharge control device 7500 (2) can discharge the power of the storage battery 7400 together with the storage battery charge / discharge control device 7500 (1). The detailed configuration content of the storage battery charge / discharge control device 7500 (2) may be the same as the configuration content of the storage battery charge / discharge control device 7500 (1), and thus the description thereof is omitted here. To do.

  For this reason, the wireless system 7000 can efficiently discharge the storage battery 7400 in a shorter time, and can supply necessary and sufficient power to the wireless device 7300 with higher power consumption.

  However, by discharging the storage battery 7400 through the two paths of the storage battery charge / discharge control device 7500 (1) and the storage battery charge / discharge control device 7500 (2), the storage battery 7400 is discharged. Since it is performed relatively quickly, the backup time is relatively short.

  In FIG. 7, two examples of the storage battery charge / discharge control device 7500 (1) and the storage battery charge / discharge control device 7500 (2) are shown as examples. You may comprise as a wireless system provided with the charging / discharging control apparatus 7500. FIG.

  Further, the storage battery charge / discharge control device 7500 (1) and the storage battery charge / discharge control device 7500 (2) may each include a storage battery 7400 and the like. That is, the storage battery charge / discharge control device 7500 (1) and the storage battery charge / discharge control device 7500 (2) are connected in parallel to each other on the output side (wireless device 7300 side), and the input side (storage battery The battery side) may be connected to the corresponding individual storage battery.

  In this way, when the storage battery charge / discharge control device 7500 (1) and the storage battery charge / discharge control device 7500 (2) are connected to the corresponding individual storage batteries, the first The discharge power can be increased without incurring a reduction in the discharge period with respect to the embodiment.

(Third embodiment)
FIG. 8 is a diagram illustrating a configuration outline of a negative voltage power feeding type wireless system 8000 including the charge / discharge control device 8500 for the storage battery according to the third embodiment. In FIG. 8, the wireless device 8300 is illustrated as a typical example of the load, but the load may be arbitrary and is not limited to the wireless device 8300. On the other hand, the wireless device 8300 is a representative of an important infrastructure that is strongly required to operate and operate as a means of contacting disaster victims in the event of an unforeseen situation such as a failure of the commercial power supply 8100 or a natural disaster. This is a typical example. The negative voltage power supply system is widely used as a power supply system for fixed telephones and the like.

  As can be understood from FIG. 8, the wireless system 8000 includes a commercial power supply 8100 and a power supply unit 8200 that converts power from the commercial power supply 8100 into appropriate power corresponding to an input to the wireless device 8300. The power supply unit 8200 may be constituted by an AC-DC converter, for example, and supplies a negative voltage.

  In addition, in the wiring for supplying power from the power supply unit 8200 to the wireless device 8300, when the power supply from the power supply unit 8200 is interrupted, backup power can be supplied instead. (1) is connected.

  The storage battery charge / discharge control device 8500 (1) is connected to a storage battery 8400 serving as a backup power source when a failure occurs. The storage battery 8400 has a configuration in which a plurality of secondary batteries such as lithium ion batteries are connected in parallel or / and in series so as to have desired electrical characteristics and capacity corresponding to the power consumption of the wireless device 8300 and the like. Also good.

  In addition, the storage battery charge / discharge control device 8500 (1) converts the power of the storage battery 8400 into power suitable for the wireless device 8300 and supplies it as negative power as backup power when a failure occurs. A type DC-DC converter 8510 is provided.

  In addition, the storage battery charge / discharge control device 8500 (1) adds the charging voltage generated by the bidirectional insulated DC-DC converter 8510 when charging the storage battery 8400 (normal time) to store the storage battery 8400. A step-down DC-DC converter 8520 for generating a charging voltage for raising the battery 8400 to a full charging voltage. The step-down DC-DC converter 8520 can be non-insulated. The bidirectional insulated DC-DC converter 8510 includes an insulated transformer 8511 in which bridge circuits are arranged on the primary side and the secondary side, respectively.

  As can be understood from FIG. 8, the wireless system 8000 includes a storage battery charge / discharge control device 8500 (2) connected in parallel to the storage battery charge / discharge control device 8500 (1). In FIG. 8, the storage battery charge / discharge control device 8500 (2) can discharge the power of the storage battery 8400 together with the storage battery charge / discharge control device 8500 (1). The detailed configuration content of the storage battery charge / discharge control device 8500 (2) may be the same as the configuration content of the storage battery charge / discharge control device 8500 (1); To do.

  Therefore, the wireless system 8000 can efficiently discharge the storage battery 8400 in a shorter time, and can supply necessary and sufficient power to the wireless device 8300 with higher power consumption.

  However, by discharging the storage battery 8400 through two paths of the storage battery charge / discharge control device 8500 (1) and the storage battery charge / discharge control device 8500 (2), the storage battery 8400 is discharged. Since it is performed relatively quickly, the backup time is relatively short.

  FIG. 8 shows two examples of the storage battery charge / discharge control device 8500 (1) and the storage battery charge / discharge control device 8500 (2). You may comprise as a wireless system provided with the charging / discharging control apparatus 8500 of a battery.

  The storage battery charge / discharge control device 8500 (1) and the storage battery charge / discharge control device 8500 (2) may each include a storage battery 8400 and the like. That is, the storage battery charge / discharge control device 8500 (1) and the storage battery charge / discharge control device 8500 (2) are connected in parallel to each other on the output side (wireless device 8300 side), and the input side (storage battery The battery side) may be connected to the individual storage batteries.

  As described above, when the storage battery charge / discharge control device 8500 (1) and the storage battery charge / discharge control device 8500 (2) are respectively connected to individual storage batteries, the first implementation is performed. The discharge power can be increased without causing a reduction in the discharge period with respect to the form.

  A charge / discharge control device for a storage battery according to the present invention is a charge / discharge control device for a storage battery comprising a bidirectional insulation type DC-DC converter for charging / discharging the storage battery. A step-down DC-DC converter having a bidirectional insulation type DC-DC converter and an input side connected in parallel and an output side connected in series so as to increase the charging voltage from the DC-DC converter To do.

  As a result, even if the winding ratio of the transformer of the bidirectional insulated DC-DC converter is set corresponding to the voltage drop of the storage battery when the storage battery is discharged, the supply voltage to the load is reduced. Based on this, it is possible to perform a charging operation by generating an appropriate charging voltage for the storage battery.

  For example, the transformer turns ratio of the bidirectional insulated DC-DC converter is set to 4: 3 so that the supply voltage to the load is 48V even when the discharge end voltage of the storage battery during discharge is 36V. In this case, the charging voltage from the bidirectional insulated DC-DC converter, which is generated based on 48V as the supply voltage to the load even during charging, is 36V.

  On the other hand, the full charge voltage of the storage battery is 54 V, for example, and the storage battery is fully charged with the charge voltage 36 V from the bidirectional insulated DC-DC converter generated based on the supply voltage to the load of 48 V. It cannot be fully charged to voltage.

  In the present invention, at least a voltage of at least 18V (= 54V-36V), which is insufficient to fully charge the storage battery to the full charge voltage, is connected in parallel between the bidirectional insulated DC-DC converter and the input side. The down DC-DC converter generates the supply voltage to the load based on 48V.

  Then, the voltage generated by the step-down DC-DC converter is added to the output of the bidirectionally-insulated DC-DC converter in which the step-down DC-DC converter and the output side are connected in series, and then as a charging voltage. It will be supplied to the battery for power storage.

  In the storage battery charge / discharge control device according to the present invention, the bidirectional insulation type DC-DC converter is preferably a regenerative converter. Thereby, surplus power can be appropriately regenerated to the storage battery, and a power-saving storage battery charge / discharge control device with reduced power loss can be realized.

  The charge / discharge control device for a storage battery according to the present invention is more preferably a switch element that is short-circuited at the output terminal on the storage battery side of the step-down DC-DC converter to form a current path when the storage battery is discharged. It is characterized by providing. As a result, a current path is quickly formed when the storage battery is discharged, and appropriate discharge processing can be performed without delay.

  In the storage battery charge / discharge control device according to the present invention, more preferably, the switch element is short-circuited when the storage battery is discharged and opened when the storage battery is charged. This makes it possible to smoothly switch between the charging voltage raising process during charging and the formation of a current path during discharging, and there is a concern that power supply abnormalities may occur and the supply of power to the load may be delayed. However, it is possible to quickly switch and supply power from the backup power source.

  In the storage battery charge / discharge control device according to the present invention, more preferably, the storage battery supplies power to the load instead of the commercial power supply when the power supply from the commercial power supply used during normal operation is delayed. It is a backup power supply to supply. This makes it possible to continue supplying power to the load even when a power failure occurs. For example, it is suitable for maintaining operation of disaster infrastructure, which is particularly necessary when a large-scale disaster occurs. A discharge control device can be realized.

  Further, in the charge / discharge control device for a storage battery according to the present invention, more preferably, the winding ratio of the insulation transformer provided in the bidirectional insulation type DC-DC converter is different from the storage battery even at the discharge end voltage of the storage battery. The winding ratio is such that a desired voltage can be supplied to the load. As a result, even when the output voltage of the storage battery gradually decreases from the fully charged voltage (for example, 54V) with discharge, it can be used as a backup power source up to a predetermined discharge end voltage (for example, 36V). For this reason, it is possible to fully use the stored power of the storage battery as a backup power source, and the backup possible time can be extended to the maximum according to the electrical performance of the storage battery.

  In the storage battery charge / discharge control device according to the present invention, more preferably, the bidirectionally insulated DC-DC converter has a bridge circuit composed of four switching elements that are turned on and off at the time of charging. It prepares for. Further, the charge / discharge control device for a storage battery according to the present invention is characterized by further comprising a charging bridge control circuit for driving four switching elements constituting a bridge circuit provided on the commercial power supply side of the transformer. To do.

  As a result, when the storage battery is charged, the four switching elements included in the bridge circuit are appropriately driven, and the charging operation can be performed with desired charging characteristics corresponding to the storage battery. In addition, since the electric power used for charging can be obtained by branching in parallel from the power supply line supplied to the load, all of the voltage required for charging based on the voltage (for example, 48V) supplied to the load or A part of the bidirectional insulation type DC-DC converter can be generated.

  Further, in the storage battery charge / discharge control device according to the present invention, more preferably, the charging bridge control circuit generates a desired raised voltage for the switching element of the step-down DC-DC converter when charging the storage battery. On / off control is performed as described above.

  As a result, it is possible to generate a voltage (for example, 54V-36V = 18V) that increases the step-down DC-DC converter when charging the storage battery. The step-down DC-DC converter generates a charging voltage for fully charging the storage battery, which is insufficient only by the bi-directional insulation type DC-DC converter generation, based on the voltage (for example, 48V) supplied to the load. can do.

  Further, the charge / discharge control device for a storage battery according to the present invention is more preferably characterized in that a desired raised voltage is larger than a difference between a discharge end voltage and a full charge voltage of the storage battery. Thereby, the voltage generated by the step-down DC-DC converter is added to the voltage generated by the bidirectional insulation type DC-DC converter to obtain a necessary and sufficient charging voltage for fully charging the storage battery. Is possible.

  In the storage battery charge / discharge control device according to the present invention, more preferably, the charging bridge control circuit is stopped when the storage battery is discharged. Thus, control circuit switching between charging and discharging is smoothly performed, and unnecessary power consumption of unnecessary control circuits can be avoided, so that power-saving and energy-saving control can be realized.

  In the storage battery charge / discharge control device according to the present invention, more preferably, the bidirectionally isolated DC-DC converter has a bridge circuit composed of four switching elements driven on and off at the time of discharge. It is provided on the side. The charge / discharge control apparatus for a storage battery according to the present invention further includes a discharge bridge control circuit for driving four switching elements constituting a bridge circuit provided on the storage battery side of the transformer. And

  As a result, when the storage battery is discharged, the four switching elements included in the bridge circuit can be appropriately driven to perform the discharge operation of the storage battery so as to match the desired electrical characteristics corresponding to the load. It becomes. In addition, since the voltage of the battery for storage is boosted and output so as to correspond to the winding ratio of the transformer, even if the voltage of the battery for storage decreases as a result of discharge, the bidirectional insulation type is used until the discharge end voltage The DC-DC converter can generate a voltage (for example, 48V) supplied to the load.

  Further, in the storage battery charge / discharge control device according to the present invention, more preferably, the discharge bridge control circuit includes a switch element disposed between the output terminals on the storage battery side of the step-down DC-DC converter. It is characterized by short-circuiting when discharging from the battery. As a result, a current path that circulates to the storage battery is formed, and a smooth discharge operation is possible.

  The storage battery charge / discharge control device according to the present invention is more preferably characterized in that the discharge bridge control circuit opens the switch element when the storage battery is charged. Thus, when charging the storage battery, the high voltage side is connected in series to the low voltage side of the bidirectional insulated DC-DC converter without short-circuiting the output terminals on the storage battery side of the step-down DC-DC converter. Therefore, a reliable and stable charge voltage raising process can be performed.

  In the charge / discharge control device for a storage battery according to the present invention, more preferably, the storage battery is a backup power source for supplying power to the wireless device. A wireless device is one of the typical disaster infrastructures, and is one of the loads in which stable operation is strongly required particularly when a large-scale disaster occurs in which a power failure occurs. Therefore, the present invention is particularly suitable for the charge / discharge control device for a storage battery according to the present invention, which can perform a charging process and a discharging process stably and without resource delay on a storage battery as a backup power source.

  The wireless systems 1000, 7000, 8000 and the like exemplified in the above-described embodiments are not limited to the description in the embodiments, but appropriately within the scope of the technical idea described in the embodiments and within the obvious range. The configuration, operation, operation method, and the like can be changed. In addition, for convenience of explanation, in the embodiment, even the matters individually described may be applied by appropriately combining the configurations within a self-evident range, and the operations may be appropriately combined and arranged.

  The storage battery charge / discharge control device according to the present invention can be widely applied as a storage battery charge / discharge control device including a bidirectional insulation type DC-DC converter for charging / discharging various secondary batteries such as lithium ion batteries. .

  1000 ... Wireless system, 1100 ... Commercial power supply, 1200 ... Power supply unit, 1300 ... Wireless device, 1400 ... Battery for storage, 1500 ... Charge / discharge control device for battery, 1510 ... Bidirectional insulation type DC-DC converter, 1511 .. Insulated transformer, 1520 .. Step-down DC-DC converter.

Claims (8)

In a storage battery charge / discharge control device comprising a bidirectional insulated DC-DC converter that charges and discharges to and from a storage battery,
The bidirectional insulation type DC-DC converter and the input side are connected in parallel and the output side is connected in series so as to increase the charging voltage from the bidirectional insulation type DC-DC converter when charging the storage battery. A charge-discharge control device for a storage battery, comprising: a step-down DC-DC converter. The charge / discharge control device for a storage battery according to claim 1,
The output terminal on the power storage battery side of the step-down DC-DC converter includes a switch element that is short-circuited when the power storage battery is discharged to form a current path,
The charge / discharge control device for a storage battery, wherein the switch element is short-circuited when the storage battery is discharged and opened when the storage battery is charged. In the charging / discharging control apparatus of the battery for electrical storage as described in any one of Claim 1 or Claim 2,
The winding ratio of the insulating transformer included in the bidirectional insulating DC-DC converter is a winding ratio that can supply a desired voltage from the storage battery to the load even at the final discharge voltage of the storage battery. A charge / discharge control device for a storage battery characterized by the above. The charge / discharge control device for a storage battery according to any one of claims 1 to 3,
The bidirectional insulation type DC-DC converter is disposed on the commercial power supply side of the transformer, and includes a bridge circuit composed of four switching elements that are driven on and off during charging.
A charging bridge control circuit for driving four switching elements constituting a bridge circuit provided on the commercial power supply side of the transformer,
The charging bridge control circuit controls on / off of the switching element of the step-down DC-DC converter so that a desired raised voltage is generated when charging the storage battery. Charge / discharge control device. The charge / discharge control device for a storage battery according to claim 4,
The desired raised voltage is greater than a difference between a discharge end voltage and a full charge voltage of the battery for storage,
The charging bridge control circuit is stopped when the power storage battery is discharged. The charge / discharge control device for a storage battery according to any one of claims 1 to 5,
The bi-directional insulation type DC-DC converter is disposed on the power storage battery side of a transformer, and includes a bridge circuit composed of four switching elements that are driven on and off during discharge.
A charge / discharge control device for a storage battery, comprising: a discharge bridge control circuit for driving four switching elements that constitute a bridge circuit provided on the storage battery side of the transformer. In the charging / discharging control apparatus of the battery for electrical storage according to claim 6,
The discharge bridge control circuit short-circuits a switch element disposed between output terminals on the power storage battery side of the step-down DC-DC converter when discharging from the power storage battery,
The discharge bridge control circuit opens the switch element when the storage battery is charged. A charge / discharge control device for a storage battery. A power supply unit that generates a voltage to be supplied to a wireless device from a commercial power supply, and a charge / discharge control device for a storage battery according to claim 7, wherein a primary side is connected between the power supply unit and the wireless device, and the power storage And a storage battery connected to the secondary side of the battery charge / discharge control device.

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