JP6056010B2 - Power supply - Google Patents

Description

  The present invention relates to a power supply device including a power storage unit.

  Conventionally, for example, Patent Document 1 proposes a power supply device (uninterruptible power supply device) including a power storage unit as a protection device against an instantaneous voltage drop.

  A schematic block diagram of this uninterruptible power supply circuit is shown in FIG. In FIG. 10, AC power supplied from the commercial AC power supply 101 is supplied to the load 105 via the switching unit 103. Further, the AC power is input to the inverter unit 107. The switching unit 103 is controlled to be turned on / off by the switching drive unit 108.

  A power storage unit 111 including an electrolytic capacitor 109 is connected to the inverter unit 107, and the inverter unit 107 converts AC power into DC to charge the electrolytic capacitor 109, or conversely, electric energy held in the electrolytic capacitor 109. DC / AC conversion function. In the latter case, the high frequency component is removed by the filter 113.

  In addition, an auxiliary charging unit 115 is provided to charge the electrolytic capacitor 109 of the power storage unit 111. The auxiliary charging unit 115 is controlled to be turned on / off by a drive signal given by the auxiliary charging driving unit 117. Each switching element of the inverter unit 107 is controlled to be turned on / off by a drive signal provided by the inverter drive unit 119.

  The input voltage detection unit 121 monitors the amplitude (peak value or effective value) of the voltage of the AC power supplied from the commercial AC power supply 101 and gives the amplitude value to the control unit 123. The charging voltage detection unit 125 detects the charging voltage held in the electrolytic capacitor 109 and inputs the voltage value to the control unit 123. The output voltage detection unit 127 detects an AC output voltage applied to the load 105 and inputs the amplitude (peak value or effective value) of the voltage to the control unit 123. The load current supplied to the load 105 is detected by the current transformer 129 and the load current detection unit 131, and the current value is input to the control unit 123.

  Next, the operation of such an uninterruptible power supply will be described. When the voltage value detected by the charging voltage detection unit 125 is equal to or lower than the first predetermined value V1, the control unit 123 causes the inverter unit 107 to pass through the inverter drive unit 119 until the rated voltage Vf (Vf> V1) is reached. Operate and charge the electrolytic capacitor 109.

  In addition, since the charging voltage of the electrolytic capacitor 109 decreases due to natural discharge, when the voltage value decreases to the second predetermined value V2 (normally V1 <V2 <Vf), the voltage value detected by the charging voltage detection unit 125 is obtained. Based on this, the control unit 123 recognizes this and charges the electrolytic capacitor 109 only by the auxiliary charging unit 115 via the auxiliary charging driving unit 117. Then, when the voltage value detected by the charging voltage detection unit 125 reaches the rated voltage Vf, the operation of the auxiliary charging unit 115 is stopped.

  Next, when the voltage of the commercial AC power supply 101 temporarily decreases, the control unit 123 turns off the switching unit 103 via the switching drive unit 108 and disconnects the load 105 from the commercial AC power supply 101. At the same time, the inverter drive unit 119 operates the inverter unit 107 to convert the voltage held in the electrolytic capacitor 109 to DC / AC, shapes the waveform via the filter 113, and supplies the waveform to the load 105.

  When the voltage drop of the AC power of the commercial AC power supply 101 is resolved, the control unit 123 stops the operation of the inverter unit 107 and then immediately connects the commercial AC power supply 101 and the load 105 by the switching unit 103. Thereby, even if the voltage of the commercial AC power supply 101 temporarily decreases (about 1 second), AC power can be supplied to the load 105 almost without interruption.

JP 2008-306889 A

  According to the uninterruptible power supply described above, AC power can be supplied to the load 105 even if the voltage of the commercial AC power supply 101 temporarily decreases. However, while the electrolytic capacitor 109 is being charged by the inverter unit 107, When the voltage of the commercial AC power supply 101 decreases, the control unit 123 must switch the inverter unit 107 that has been operating to charge the electrolytic capacitor 109 so that the electrolytic capacitor 109 is immediately discharged. In this case, since the control target of the inverter unit 107 is switched from the voltage of the electrolytic capacitor 109 to the output voltage detected by the output voltage detection unit 127, discontinuity occurs in the operation of the inverter unit 107. As a result, there has been a problem that the output voltage fluctuates temporarily and the AC power output to the load 105 becomes unstable. Such a problem becomes more conspicuous because the larger the capacity of the power storage unit 111, the longer it takes to charge.

  An object of the present invention is to solve the above-described conventional problems, and to provide a power supply device that can stably supply power to a load even when a power supply voltage of the power storage unit decreases during charging. To do.

  In order to solve the conventional problem, a power supply device of the present invention includes a bidirectional inverter electrically connected to a system power supply via a switch, a power storage unit electrically connected to the bidirectional inverter, An input / output voltage detection unit electrically connected to the system power supply side of the bidirectional inverter, a current detection unit for detecting a current (I) flowing through the power storage unit, the switch, the bidirectional inverter, and the input / output voltage And a control unit electrically connected to the current detection unit, wherein the control unit maintains the current (I) when the current (I) reaches a predetermined current (Ik). If the current (I) does not reach the predetermined current (Ik), the input / output voltage (Va) detected by the input / output voltage detection unit is lower than the specified lower limit voltage (Vad) of the system power supply. Voltage (Vak) His, with each performed on the bi-directional inverter, the at the time of discharging of power storage unit to turn off the switch, at other times is to control to turn on the switch.

  The power supply device of the present invention includes a bidirectional inverter electrically connected to a system power supply via a switch, a DC / DC converter electrically connected to the bidirectional inverter, and the DC / DC converter. A power storage unit that is electrically connected, a system power supply side voltage detection unit that is electrically connected to the system power supply side of the bidirectional inverter and detects a system power supply side voltage (Vi), and the bidirectional inverter A DC / DC converter side voltage detection unit that is electrically connected to the DC / DC converter side and detects a DC / DC converter side voltage (Vd); and a power storage unit voltage (Vb) that is electrically connected to the power storage unit. Power storage unit voltage detection unit for detecting current, current detection unit for detecting current (I) flowing in the power storage unit, the switch, bidirectional inverter, DC / DC converter, system power supply side voltage A control unit electrically connected to the output unit, the DC / DC converter side voltage detection unit, the power storage unit voltage detection unit, and the current detection unit, and in the operation of the bidirectional inverter, the control unit includes: When the DC / DC converter side voltage (Vd) reaches the first predetermined DC / DC converter side voltage (Vdk1), control for maintaining the DC / DC converter side voltage (Vd) is performed with a first priority, and the DC / DC If the DC converter side voltage (Vd) does not reach the first predetermined DC / DC converter side voltage (Vdk1) and the current (I) reaches the predetermined current (Ik), the current (I) is maintained. The DC / DC converter side voltage (Vd) does not reach the first predetermined DC / DC converter side voltage (Vdk1), and the current (I) is the predetermined current. If it has not reached Ik), control is performed with the third priority so that the system power supply side voltage (Vi) becomes a predetermined system power supply side voltage (Vik) lower than the specified lower limit voltage (Vad) of the system power supply. At the same time, in the operation of the DC / DC converter, when the power storage unit voltage (Vb) reaches the predetermined power storage unit voltage (Vbk), the control unit gives priority to control for maintaining the power storage unit voltage (Vb). If the power storage unit voltage (Vb) does not reach the predetermined power storage unit voltage (Vbk), the DC / DC converter side voltage (Vd) is equal to the first predetermined DC / DC converter side voltage (Vdk1). The second preferential DC / DC converter side voltage (Vdk2) is controlled with the second priority, and the control unit operates the bidirectional inverter and the DC / DC converter. These operations are performed in parallel, and the switch is turned off when the power storage unit is discharged, and the switch is turned on at other times.

  The power supply device of the present invention includes a bidirectional inverter electrically connected to a system power supply via a switch, a DC / DC converter electrically connected to the bidirectional inverter, and the DC / DC converter. A power storage unit that is electrically connected, a system power supply side voltage detection unit that is electrically connected to the system power supply side of the bidirectional inverter and detects a system power supply side voltage (Vi), and the bidirectional inverter A DC / DC converter side voltage detection unit that is electrically connected to the DC / DC converter side and detects a DC / DC converter side voltage (Vd); and a power storage unit voltage (Vb) that is electrically connected to the power storage unit. Power storage unit voltage detection unit for detecting current, current detection unit for detecting current (I) flowing in the power storage unit, the switch, bidirectional inverter, DC / DC converter, system power supply side voltage A control unit electrically connected to the output unit, the DC / DC converter side voltage detection unit, the power storage unit voltage detection unit, and the current detection unit, and in the operation of the bidirectional inverter, the control unit includes: When the DC / DC converter side voltage (Vd) reaches the first predetermined DC / DC converter side voltage (Vdk1), control for maintaining the DC / DC converter side voltage (Vd) is performed with a first priority, and the DC / DC If the DC converter side voltage (Vd) does not reach the first predetermined DC / DC converter side voltage (Vdk1), the system power supply side voltage (Vi) is lower than the specified lower limit voltage (Vad) of the system power supply. The control is performed with the second priority so that the predetermined system power supply side voltage (Vik) is obtained, and in the operation of the DC / DC converter, the control unit has the power storage unit voltage (Vb) already existing. If the power storage unit voltage (Vbk) is reached, the control for maintaining the power storage unit voltage (Vb) is performed with first priority, the power storage unit voltage (Vb) has not reached the predetermined power storage unit voltage (Vbk), and When the current (I) reaches the predetermined current (Ik), the control for maintaining the current (I) is performed with the second priority, and the power storage unit voltage (Vb) reaches the predetermined power storage unit voltage (Vbk). If the current (I) does not reach the predetermined current (Ik), the DC / DC converter side voltage (Vd) is lower than the first predetermined DC / DC converter side voltage (Vdk1). The control to achieve the second predetermined DC / DC converter side voltage (Vdk2) is performed with the third priority, and the control unit performs the operation of the bidirectional inverter and the operation of the DC / DC converter in parallel. And the storage Control is performed so that the switch is turned off when the electric section is discharged, and the switch is turned on at other times.

  According to the power supply device of the present invention, when the current I flowing through the power storage unit reaches the predetermined current Ik, the current I is controlled and the input / output voltage Va is controlled to be the predetermined voltage Vak. Yes. Therefore, when the current I becomes lower than the predetermined current Ik and the input / output voltage Va becomes lower than the predetermined voltage Vak due to the occurrence of a power failure or the like, the bidirectional inverter operates to discharge the power storage unit to increase the input / output voltage Va. . At this time, since the bidirectional inverter continues the control so that the input / output voltage Va becomes the predetermined voltage Vak, the magnitude of the input / output voltage Va can be obtained without performing any special switching operation for the bidirectional inverter. As a result, the power storage unit is smoothly charged and discharged. Therefore, the power supply device of the present invention has an effect that power can be stably supplied to the load even when the input / output voltage Va is reduced during charging of the power storage unit.

  Further, according to the power supply device of the present invention, in the configuration in which the DC / DC converter for charging and discharging the power storage unit is connected in addition to the bidirectional inverter, the control unit performs the third priority operation from the first priority operation in the bidirectional inverter. Since the priority operation and the first priority operation to the second priority operation in the DC / DC converter are performed in parallel, the DC / DC converter performs a special switching operation as well as the bidirectional inverter. The charging / discharging of the power storage unit is performed smoothly without any problems. Therefore, the power supply device of the present invention has an effect that power can be stably supplied to the load even when the system power supply voltage Vi decreases during charging of the power storage unit.

  Furthermore, according to the power supply device of the present invention, in the configuration in which the DC / DC converter for charging / discharging the power storage unit is connected in addition to the bidirectional inverter, the control unit performs the second priority operation from the first priority operation in the bidirectional inverter. Since the priority operation and the first priority operation to the third priority operation in the DC / DC converter are performed in parallel, the DC / DC converter performs a special switching operation as well as the bidirectional inverter. The charging / discharging of the power storage unit is performed smoothly without any problems. Therefore, the power supply device of the present invention has an effect that power can be stably supplied to the load even when the system power supply voltage Vi decreases during charging of the power storage unit.

1 is a block circuit diagram of a power supply device according to Embodiment 1 of the present invention. 2 is a time-dependent characteristic diagram of voltage / current of the power supply device according to the first embodiment of the present invention, where (a) is a time-dependent characteristic diagram of input / output voltage Va, (b) is a time-dependent characteristic diagram of power storage unit voltage Vb, and (c) is a power storage unit. Time characteristics of current I flowing through Block circuit diagram of a power supply apparatus according to Embodiment 2 of the present invention FIG. 4 is a time-dependent characteristic diagram of a voltage / current of a power supply device according to Embodiment 2 of the present invention, where (a) is a time-dependent characteristic diagram of an input / output voltage Va, (b) is a time-dependent characteristic diagram of a power storage unit voltage Vb, Time characteristics of current I flowing through Block circuit diagram of a power supply device according to Embodiment 3 of the present invention Block circuit diagram of a power supply device according to Embodiment 4 of the present invention FIG. 7A is a time-dependent characteristic diagram of a power supply device according to Embodiment 4 of the present invention, FIG. 5A is a time-dependent characteristic diagram of a system power supply-side voltage Vi, FIG. 5B is a time-dependent characteristic diagram of a DC / DC converter-side voltage Vd; ) Is a time-dependent characteristic diagram of the power storage unit voltage Vb, and (d) is a time-dependent characteristic diagram of the current I flowing through the power storage unit. FIG. 6 is a time-dependent characteristic diagram of voltage-current characteristics of a power supply device according to Embodiment 5 of the present invention, where (a) is a time-dependent characteristic diagram of system power supply-side voltage Vi, (b) is a time-dependent characteristic diagram of DC / DC converter-side voltage Vd, ) Is a time-dependent characteristic diagram of the power storage unit voltage Vb, and (d) is a time-dependent characteristic diagram of the current I flowing through the power storage unit. Block circuit diagram of a power supply device according to Embodiment 6 of the present invention Schematic block diagram of a conventional uninterruptible power supply circuit

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block circuit diagram of a power supply device according to Embodiment 1 of the present invention. 2A and 2B are graphs of voltage / current characteristics of the power supply device according to the first embodiment of the present invention. FIG. 2A is a graph of characteristics of the input / output voltage Va with time, FIG. ) Is a time-dependent characteristic diagram of the current I flowing through the power storage unit.

  In FIG. 1, a power supply device 11 includes a bidirectional inverter 17 that is electrically connected to a system power supply 13 via a switch 15, a power storage unit 19 that is electrically connected to the bidirectional inverter 17, and a bidirectional inverter 17. The input / output voltage detection unit 21 electrically connected to the system power supply 13 side, the current detection unit 22 that detects the current I flowing through the power storage unit 19, the switch 15, the bidirectional inverter 17, and the input / output voltage detection unit 21. And a control unit 23 electrically connected to the current detection unit 22. The control unit 23 performs control to maintain the current I if the current I reaches the predetermined current Ik, and the input / output voltage Va detected by the input / output voltage detection unit 21 if the current I does not reach the predetermined current Ik. However, control is performed on the bidirectional inverter 17 so that the predetermined voltage Vak is lower than the specified lower limit voltage Vad of the system power supply 13, and the switch 15 is turned off when the power storage unit 19 is discharged. Controls to turn on the switch 15.

  Thereby, when the current I becomes lower than the predetermined current Ik due to the occurrence of a power failure and the input / output voltage Va becomes lower than the predetermined voltage Vak, the bidirectional inverter 17 discharges the power storage unit 19 to increase the input / output voltage Va. To work. At this time, since the bidirectional inverter 17 continues the control such that the input / output voltage Va becomes the predetermined voltage Vak, the input / output voltage Va can be controlled without performing any special switching operation on the bidirectional inverter 17. The power storage unit 19 is smoothly charged and discharged according to the size. Therefore, even if the input / output voltage Va decreases while the power storage unit 19 is being charged, the power supply device 11 that can stably supply power to the load is obtained.

  Hereinafter, the configuration and operation of the first embodiment will be described more specifically. The first embodiment will be described as a power supply device 11 for supplying power from a power storage unit at the time of a power failure of a system power supply. In the following explanation, power failure is not limited to long-term power failure, but also includes instantaneous power failure and cases where the system power supply voltage temporarily drops below the specified lower limit voltage of the system power supply. It is defined as

  In FIG. 1, a system power supply 13 is electrically connected between an input / output terminal 25 and an input / output ground terminal 27 provided in the bidirectional inverter 17 of the power supply device 11. A switch 15 is electrically connected between the system power supply 13 and the input / output terminal 25. Accordingly, the power of the system power supply 13 is input to the power supply device 11 via the switch 15.

  A load 29 is electrically connected between the input / output terminal 25 and the input / output ground terminal 27. Accordingly, the load 29 is supplied with power from either the system power supply 13 or the power supply device 11 by switching the switch 15. The on / off control of the switch 15 is performed by the control unit 23 of the power supply device 11. For this purpose, the power supply device 11 is provided with a switch control terminal 31. The switch control terminal 31 is connected to the switch 15 and also to the control unit 23. With such a configuration, a switch 15 that can be turned on and off by an external signal (for example, a relay or a semiconductor switch) is used.

  A system voltage detection unit 32 that detects the system power supply voltage Vs is electrically connected to the system power supply 13. The output of the system voltage detection unit 32 is electrically connected to the control unit 23 via the system voltage detection terminal 33. Thereby, the control part 23 can know whether the system power supply 13 is a power failure by detecting the system power supply voltage Vs.

  Next, a detailed configuration of the power supply device 11 will be described.

  The input / output terminal 25 and the input / output ground terminal 27 are provided in the bidirectional inverter 17. Therefore, since the input / output terminal 25 and the input / output ground terminal 27 are electrically connected to the AC system power supply 13, the input / output terminal 25 and the input / output ground terminal 27 perform input / output of AC power.

  A power storage unit 19 is electrically connected to the bidirectional inverter 17. Specifically, power storage unit 19 is connected between power storage unit terminal 34 and power storage unit ground terminal 35 provided in bidirectional inverter 17. The power storage unit 19 includes a capacitor. The capacitor of the power storage unit 19 stores power for continuing to move the load 29 in the event of a power failure. The capacity of the capacitor depends on the power specifications required by the load 29, the power failure frequency of the system power supply 13, the power failure period, and the like. And the quantity may be determined as appropriate. Here, assuming that a power outage over a period longer than an instant (less than 1 second) of about several seconds frequently occurs, a capacitor unit in which a plurality of capacitors are connected in series and parallel is used as the power storage unit 19. Yes. In addition, the electrical storage part 19 is not limited to a capacitor, A secondary battery may be sufficient.

  Therefore, the bidirectional inverter 17 has both a function of charging the power of the system power supply 13 to the power storage unit 19 and a function of discharging the power stored in the power storage unit 19 to the load 29 at the time of a power failure of the system power supply 13. Prepare. Therefore, the bidirectional inverter 17 performs an operation of converting the AC power of the system power supply 13 into DC power and converting the DC power of the power storage unit 19 into AC power. A circuit configuration that performs such AC / DC conversion bidirectionally is referred to as a bidirectional inverter in the first embodiment.

  The bidirectional inverter 17 is electrically connected to the control unit 23. The control unit 23 includes a microcomputer and peripheral circuits (both not shown), and outputs a control signal CT for controlling the operation of the bidirectional inverter 17. As a result, a semiconductor switching element (not shown) built in the bidirectional inverter 17 is on / off controlled.

  The input / output voltage detection unit 21 is electrically connected to the input / output terminal 25 and the input / output ground terminal 27. The input / output voltage detector 21 detects an AC voltage (input / output voltage Va) input / output to / from the bidirectional inverter 17. In the first embodiment, the input / output voltage detector 21 is connected between the input / output terminal 25 and the input / output ground terminal 27. An effective value of the AC voltage is obtained and output as the input / output voltage Va. The input / output voltage detection unit 21 is not limited to the configuration for obtaining the effective value, and may obtain the peak value or the peak value.

  The input / output voltage detection unit 21 is also electrically connected to the control unit 23. Therefore, the control unit 23 has a configuration for taking in the input / output voltage Va detected by the input / output voltage detection unit 21.

  Between the bidirectional inverter 17 and the power storage unit 19, a current detection unit 22 that detects the current I flowing through the power storage unit 19 is provided. The current detection unit 22 includes a shunt resistor and a peripheral circuit (both not shown). The current detection unit 22 has a function of outputting the current I flowing through the power storage unit 19 including positive / negative information. Therefore, the current detection unit 22 is also electrically connected to the control unit 23. The control unit 23 takes in the current I from the output of the current detection unit 22. The current detection unit 22 may be provided between the power storage unit ground terminal 35 and the power storage unit 19. Further, the current detection unit 22 is not limited to the configuration including the shunt resistor and the peripheral circuit, and may be based on a principle of magnetic detection in a non-contact manner, such as a conventional current transformer or a Hall element.

  In addition, the control unit 23 is configured to output a switch signal SW for controlling on / off of the switch 15 to the switch 15.

  Next, the operation of the power supply device 11 will be described with reference to FIG.

  FIG. 2A is a time-dependent characteristic diagram of the input / output voltage Va, where the horizontal axis represents time and the vertical axis represents the input / output voltage Va. FIG. 2B is a time-dependent characteristic diagram of the power storage unit voltage Vb, where the horizontal axis represents time and the vertical axis represents the power storage unit voltage Vb. FIG. 2C is a time characteristic diagram of the current I flowing through the power storage unit 19, where the horizontal axis indicates time and the vertical axis indicates the current I. In FIG. 2C, the current I when charging the power storage unit 19 is defined as positive, and the current I when discharging is defined as negative.

  In FIG. 2, time t <b> 0 is when the system power supply 13 is normal and the power storage unit 19 is being charged. Accordingly, the switch 15 is in an on state since the power storage unit 19 is not discharged. Since the control unit 23 determines whether or not a power failure has occurred based on the system power supply voltage Vs output from the system voltage detection unit 32, no power failure has occurred at time t0 and the system power supply 13 is normal. 23 turns on the switch 15.

  Here, since the upper limit and lower limit voltages of the system power supply 13 are determined according to the standard, the upper limit is hereinafter referred to as a specified upper limit voltage Vau and the lower limit is referred to as a specified lower limit voltage Vad. In the first embodiment, as an example, it is assumed that the voltage of the system power supply 13 is AC 100V (effective value), and the standard of the voltage swing is ± 6V. Therefore, the specified upper limit voltage Vau is 106V and the specified lower limit voltage Vad is 94V. At time t0, the system power supply voltage Vs is assumed to be exactly 100V.

  In this state, the control unit 23 detects the control to maintain the current I if the current I reaches the predetermined current Ik, and the input / output voltage detection unit 21 detects that the current I does not reach the predetermined current Ik. The bidirectional inverter 17 is controlled such that the input / output voltage Va becomes a predetermined voltage Vak lower than the specified lower limit voltage Vad of the system power supply 13. The specific operation is as follows.

  Since the specified lower limit voltage Vad is 94 V as described above, the control unit 23 stores in advance, for example, 90 V as a predetermined voltage Vak in a memory (not shown) of the microcomputer.

  The control unit 23 also stores a predetermined current Ik in the memory. Here, the predetermined current Ik is determined as a value obtained by subtracting a margin including an error of the current detection unit 22 from an allowable maximum current for charging the power storage unit 19.

  The control unit 23 takes in the input / output voltage Va from the input / output voltage detection unit 21 and takes in the current I from the current detection unit 22. Then, the control unit 23 compares the input / output voltage Va with the predetermined voltage Vak and also compares the current I with the predetermined current Ik. Here, comparing the input / output voltage Va with the predetermined voltage Vak, as described above, the system power supply voltage Vs (= input / output voltage Va) is 100V and the predetermined voltage Vak is 90V at time t0. Controls the bidirectional inverter 17 to lower the input / output voltage Va to a predetermined voltage Vak. As a result, bidirectional inverter 17 operates to draw power from system power supply 13 and charge power storage unit 19. Therefore, as shown in FIG. 2B, the power storage unit voltage Vb increases with time from time t0. At this time, as shown in FIG. 2C, the current I flowing through the power storage unit 19 reaches the predetermined current Ik. Therefore, the control unit 23 performs control so that the current I becomes the predetermined current Ik so that no overcurrent flows at time t0. Therefore, the control unit 23 gives priority to the control in which the current I becomes the predetermined current Ik over the control in which the input / output voltage Va becomes the predetermined voltage Vak. Therefore, as shown in FIG. 2A, at time t0, the input / output voltage Va does not become the predetermined voltage Vak, and remains at the system power supply voltage Vs (= 100 V).

  In addition, in the vertical axis | shaft of FIG.2 (b), the voltage at the time of completion | finish of charge of the electrical storage part 19 is shown as the default electrical storage part voltage Vbk. In the first embodiment, as described above, power outages of several seconds occur frequently and there are many discharge opportunities of the power storage unit 19. Therefore, the capacity of the power storage unit 19 is increased. The unit voltage Vb is configured not to reach the predetermined power storage unit voltage Vbk.

  Further, on the vertical axis in FIG. 2C, the maximum current for discharging the power storage unit 19 is shown as the lower limit current -Id. Here, since the current I in the discharge direction is defined as negative, the maximum current to be discharged is referred to as a lower limit current −Id. The current I at the time of charging does not become larger than the predetermined current Ik described above. Further, since the current I at the time of discharging is substantially the current consumed by the load 29, the capacitor of the power storage unit 19 is configured in a series-parallel configuration so that the absolute value of the lower limit current -Id is within the current consumed by the load 29. Therefore, the current I varies between these current ranges.

  Between time t0 and time t1, as shown in FIG. 2A, the input / output voltage Va is stable at a constant value (100V), so the system power supply 13 is normal. During this time, the bidirectional inverter 17 continues the operation of lowering the input / output voltage Va to the predetermined voltage Vak. However, since the current I reaches the predetermined current Ik, the control for maintaining the current I is prioritized. Therefore, the power storage unit 19 is charged with a constant current. As a result, as shown in FIG. 2B, the power storage unit voltage Vb continues to rise over time.

  Next, a power failure occurs while charging power storage unit 19 at time t1. The occurrence of a power failure can be determined by the system power supply voltage Vs output from the system voltage detector 32 being lower than the specified lower limit voltage Vad as described above. When the control unit 23 determines that a power failure has occurred, the switch 15 is immediately turned off to discharge the power from the power storage unit 19 to the load 29 in order to prevent a reverse flow of power from the power storage unit 19 to the system power supply 13. However, control of bidirectional inverter 17 continues as before time t1. The specific operation in this case is as follows.

  Due to a power failure, the system power supply voltage Vs drops to 0V. Therefore, even if the switch 15 is turned off, the load 29 is connected to the input / output terminal 25, and the load 29 consumes power, so the input / output voltage Va decreases. However, when the current I reaches the predetermined current Ik, the bidirectional inverter 17 is controlled to maintain the current I and to control the input / output voltage Va to the predetermined voltage Vak (= 90 V).

  Here, when the input / output voltage Va decreases to the predetermined voltage Vak, the bidirectional inverter 17 does not need to draw the current I to the power storage unit 19 to be charged. Therefore, the current I is lower than the predetermined current Ik, and the control target is control to maintain the input / output voltage Va at the predetermined voltage Vak. At this time, since the switch 15 is off, the bidirectional inverter 17 uses the power of the power storage unit 19 in order to make the input / output voltage Va become the predetermined voltage Vak with the load 29 that consumes power connected. It operates to pull toward the input / output terminal 25 side. As a result, the power of the power storage unit 19 is discharged, and the input / output voltage Va immediately becomes the predetermined voltage Vak at time t1. At this time, the direction of the current I of the bidirectional inverter 17 is reversed as shown in FIG. 2C. However, the controlled object of the bidirectional inverter 17 itself is a power failure by setting the input / output voltage Va to the predetermined voltage Vak. Continued from before. Therefore, since it is not necessary to switch the control of the bidirectional inverter 17 according to the charging and discharging of the power storage unit 19, the operation is not unstable. Therefore, even when the power storage unit 19 is being charged, the power of the power storage unit 19 can be stably supplied to the load 29 immediately when a power failure occurs.

  Due to such an operation, the power storage unit 19 starts discharging at time t1, so that the power storage unit voltage Vb decreases with time as shown in FIG. Further, as shown in FIG. 2C, the current I flowing through the power storage unit 19 becomes negative due to discharge, and has a value corresponding to the current consumed by the load 29. In the first embodiment, it is assumed that the load 29 operates with a constant current consumption. Therefore, after time t1, the current I becomes a constant negative value.

  Thereafter, the power failure returns at time t2. This state change can also be determined by the control unit 23 monitoring the system power supply voltage Vs detected by the system voltage detection unit 32.

  When the control unit 23 determines that the power failure has been restored, the bidirectional inverter 17 adjusts the phase so as to be in phase with the system power supply 13, turns on the switch 15, and supplies the power of the system power supply 13 to the load 29. However, also in this case, the control of the bidirectional inverter 17 is the same as before time t2. Therefore, the bidirectional inverter 17 operates so as to charge the power storage unit 19 at time t2, but since there is no switching operation, there is no instability of operation associated with switching. The operation of the power supply device 11 at time t2 is the same as the operation at time t0.

  After time t2, since it is a time other than the time when the power storage unit 19 is discharged, the power storage unit 19 is charged in the same manner as from time t0 to time t1, but here, as shown in FIG. It is assumed that the system power supply 13 immediately after the power failure recovery generates a high voltage, that is, the specified upper limit voltage Vau (= 106 V). Also in this case, as at time t0, the current I reaches the predetermined current Ik, so priority control is performed so as to maintain the current I. As a result, as shown in FIG. 2A, the input / output voltage Va is stabilized at the specified upper limit voltage Vau and does not reach the predetermined voltage Vak.

  At this time, since the voltage difference between the input / output voltage Va and the predetermined voltage Vak is larger in charging the power storage unit 19 than in the case from time t0 to time t1, as shown in FIG. The gradient in the time-dependent characteristic of the voltage Vb increases.

  Thereafter, by repeating the above-described operation, the bidirectional inverter 17 operates so that the power of the power storage unit 19 can be immediately supplied to the load 29 even in an environment where frequent power failures occur. Is possible.

  With the above configuration and operation, when the current I becomes lower than the predetermined current Ik due to the occurrence of a power failure and the input / output voltage Va becomes lower than the predetermined voltage Vak, the bidirectional inverter 17 causes the power storage unit 19 to increase the input / output voltage Va. Operate to discharge. At this time, since the bidirectional inverter 17 continues the control such that the input / output voltage Va becomes the predetermined voltage Vak, the input / output voltage Va can be controlled without performing any special switching operation on the bidirectional inverter 17. The power storage unit 19 is smoothly charged and discharged according to the size. Therefore, even if the input / output voltage Va decreases while the power storage unit 19 is being charged, the power supply device 11 that can stably supply power to the load is obtained.

  In the first embodiment, the predetermined voltage Vak is set to 90 V, but this is an example, and it may be larger or smaller than this. However, if it is too large, the difference between the input / output voltage Va and the predetermined voltage Vak becomes small, so the detection accuracy of the input / output voltage detector 21 needs to be increased. On the other hand, if the predetermined voltage Vak is too small, there is a possibility that a voltage sufficient to operate the load 29 at the time of a power failure cannot be obtained. Therefore, the predetermined voltage Vak may be appropriately determined according to the detection accuracy and the required voltage value of the load 29.

  In the first embodiment, the absolute values of the predetermined current Ik and the lower limit current −Id are different values. This is because the absolute values of current allowed for charging and discharging of the power storage unit 19 are not necessarily the same. However, in accordance with the smaller absolute value, both absolute values may be the same.

(Embodiment 2)
FIG. 3 is a block circuit diagram of the power supply apparatus according to Embodiment 2 of the present invention. 4A and 4B are graphs of voltage-current characteristics of the power supply device according to Embodiment 2 of the present invention, in which FIG. 4A is a time-dependent characteristic diagram of the input / output voltage Va, FIG. 4B is a time-dependent characteristic diagram of the storage unit voltage Vb, ) Is a time-dependent characteristic diagram of the current I flowing through the power storage unit.

  In the configuration of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. That is, the characteristic configuration of the second embodiment is that a storage unit voltage detection unit 37 that is electrically connected to the control unit 23 is further provided in FIG.

  In addition, the characteristic operation in the second embodiment is as follows. When power storage unit voltage Vb detected by power storage unit voltage detection unit 37 reaches predetermined power storage unit voltage Vbk, control unit 23 prioritizes control for maintaining power storage unit voltage Vb.

  As a result, since the power storage unit 19 can be managed by the power storage unit voltage Vb, it is possible to control charging to the predetermined power storage unit voltage Vbk without continuing to charge the power storage unit 19.

  Hereinafter, the details of the configuration that characterizes the second embodiment will be described.

  In FIG. 3, a power storage unit voltage detection unit 37 is electrically connected between the power storage unit terminal 34 and the power storage unit ground terminal 35. In the second embodiment, the power storage unit voltage detection unit 37 is connected between the power storage unit terminal 34 and the power storage unit ground terminal 35, but this may be configured to be directly connected to both ends of the power storage unit 19. Good.

  The power storage unit voltage detection unit 37 has a function of detecting and outputting the power storage unit voltage Vb. Therefore, the power storage unit voltage detection unit 37 is also electrically connected to the control unit 23. Control unit 23 takes in power storage unit voltage Vb from the output of power storage unit voltage detection unit 37.

  The configuration other than the above is the same as that of the first embodiment.

  Next, an operation that characterizes the power supply device 11 according to the second embodiment will be described with reference to FIG.

  FIG. 4A is a time-dependent characteristic diagram of the input / output voltage Va, where the horizontal axis indicates time and the vertical axis indicates the input / output voltage Va. FIG. 4B is a time-dependent characteristic diagram of the power storage unit voltage Vb, where the horizontal axis represents time and the vertical axis represents the power storage unit voltage Vb. FIG. 4C is a time characteristic diagram of the current I flowing through the power storage unit 19, where the horizontal axis indicates time and the vertical axis indicates the current I. In FIG. 4C, the current I when charging the power storage unit 19 is defined as positive, and the current I when discharging is defined as negative.

  In FIG. 4, since the operation from time t0 to time t2 is the same as that in FIG. 2, detailed description thereof is omitted. Therefore, similarly to the first embodiment, the input / output voltage Va decreases during the charging of the power storage unit 19, and the power supply device 11 that can stably supply power to the load even when a power failure occurs is obtained. .

  Next, after time t2, the input / output voltage Va is the specified upper limit voltage Vau as shown in FIG. 4 (a), and the power storage unit 19 is charged as shown in FIG. 4 (b). Vb increases with time. Further, as shown in FIG. 4C, since the time after time t2 is a time other than the time of discharging, the current I maintains the predetermined current Ik. Accordingly, the power storage unit 19 is charged with a constant current. Note that, after time t2, as shown in FIG. 4A, the input / output voltage Va is assumed to be constant at the specified upper limit voltage Vau.

  In the second embodiment, since the above-described power storage unit voltage Vb and current I can be detected, the control unit 23 monitors them. Note that the monitoring operation of the current I (comparison with the predetermined current Ik) is the same as that in the first embodiment, and thus detailed description thereof is omitted.

  Thereafter, at time t3, as shown in FIG. 4B, power storage unit voltage Vb reaches predetermined power storage unit voltage Vbk. Since control unit 23 monitors power storage unit voltage Vb, bidirectional inverter 17 keeps power storage unit voltage Vb at default power storage unit voltage Vbk when power storage unit voltage Vb reaches predetermined power storage unit voltage Vbk. To control. As a result, since the power storage unit 19 is not charged, the current I does not flow. Therefore, as shown in FIG. 4C, after time t3, the current I sharply decreases and reaches zero. The reason why current I does not immediately become 0 at time t3 is that a slight fluctuation of power storage unit voltage Vb occurs due to the internal resistance of power storage unit 19.

  At the timing of this time t3, the control target of the bidirectional inverter 17 operates so as to maintain the default power storage unit voltage Vbk instead of the power storage unit voltage Vb from the current I so far. As a result, the possibility of overcharging the power storage unit 19 can be reduced.

  The operation of maintaining the power storage unit voltage Vb at the predetermined power storage unit voltage Vbk at time t3 is prioritized over the control from which the current I maintains the default current Ik from time t2 to time t3. Therefore, in the control of the bidirectional inverter 17, the control unit 23 controls the bidirectional inverter 17 so that the input / output voltage Va becomes the predetermined voltage Vak, but when the current I reaches the predetermined current Ik, The second priority control for maintaining I at the predetermined current Ik is performed, and when the power storage unit voltage Vb reaches the predetermined power storage unit voltage Vbk, the first priority for maintaining the power storage unit voltage Vb at the predetermined power storage unit voltage Vbk is performed. Take control. As a result, the input / output voltage Va decreases during charging of the power storage unit 19, and even if a power failure occurs, power can be stably supplied to the load, and overcharging and overcurrent of the power storage unit 19 can be performed. The possibility can be reduced and high reliability can be obtained.

  After time t3, the current I from the bidirectional inverter 17 to the power storage unit 19 is maintained at 0, so the bidirectional inverter 17 corresponds to the standby state. Therefore, even if a power failure occurs during this standby, the bidirectional inverter 17 is not stopped, so the control unit 23 controls the bidirectional inverter 17 so as to quickly supply the power of the power storage unit 19 to the load 29. can do.

  With the configuration and operation described above, the input / output voltage Va decreases during charging of the power storage unit 19, and even if a power failure occurs, power can be stably supplied to the load, and the power storage unit 19 is overcharged. Thus, the highly reliable power supply device 11 that can reduce the possibility of the above is obtained.

(Embodiment 3)
FIG. 5 is a block circuit diagram of a power supply device according to Embodiment 3 of the present invention.

  In the configuration of the third embodiment, the same components as those of the first and second embodiments are denoted by the same reference numerals and description thereof is omitted. That is, the characteristic configuration of the third embodiment is that an external device terminal 43 for electrically connecting the control unit 23 and the external device 41 is further provided in FIG.

  In addition, the characteristic operation in the third embodiment is as follows. The control unit 23 sets at least one of the predetermined voltage Vak, the predetermined current Ik, or the predetermined power storage unit voltage Vbk according to the variable signal K from the external device 41 input from the external device terminal 43.

  Accordingly, the predetermined voltage Vak can be freely set by the variable signal K of the external device 41. Therefore, when the power supply device 11 is used in an area where the standard of the system power supply 13 is different, it is very easy to The predetermined voltage Vak can be set according to the power situation. Further, since the predetermined current Ik can be freely set, the predetermined current Ik for monitoring the overcurrent can be easily set according to the power supply device 11 in which the specifications of the bidirectional inverter 17 and the power storage unit 19 are changed. Further, since the default power storage unit voltage Vbk can be set freely, the default power storage unit voltage Vbk for monitoring overvoltage can be easily set according to the power supply device 11 whose specification of the power storage unit 19 is changed. In addition, by simultaneously setting a plurality of the above three parameters, it is possible to easily set even when the usage region and specifications of the power supply device 11 are changed simultaneously.

  Hereinafter, the details will be described focusing on the characteristic points in the configuration of the third embodiment.

  In FIG. 5, the power supply device 11 includes a control unit 23 and an external device terminal 43 that is electrically connected to the external device 41.

  The external device 41 is for controlling the power supply device 11 from the outside, and may be a dedicated control device for the power supply device 11, or may be a computer, a tablet terminal, a smartphone, or the like.

  Other configurations are the same as those in FIG.

  Next, the operation of such a power supply device 11 will be described.

  A variable signal K for controlling the power supply device 11 is output from the external device 41. The variable signal K is input to the control unit 23 via the external device terminal 43. The variable signal K is data including at least one set value of the predetermined voltage Vak, the predetermined current Ik, or the predetermined power storage unit voltage Vbk. Therefore, the control unit 23 takes in the set value of the predetermined voltage Vak, the predetermined current Ik, or the predetermined power storage unit voltage Vbk included in the input variable signal K, and uses it as the predetermined voltage Vak, the predetermined current Ik, or the default power storage unit voltage Vbk. Set. As a result, when the variable signal K includes the predetermined voltage Vak, the bidirectional inverter 17 is controlled such that the input / output voltage Va becomes the set predetermined voltage Vak. Further, when the variable signal K includes the predetermined current Ik, the bidirectional inverter 17 is controlled so that the current I becomes the set predetermined current Ik. Bidirectional inverter 17 is controlled such that power storage unit voltage Vb becomes set default power storage unit voltage Vbk if variable signal K includes predetermined power storage unit voltage Vbk. As described in the second embodiment, the priority of these controls is the first priority for the control of the power storage unit voltage Vb, the second priority for the control of the current I, and the third priority for the control of the input / output voltage Va. .

  Since the predetermined voltage Vak can be arbitrarily changed, for example, if the power supply device 11 is portable, it can be changed to a set value according to the power situation of the destination. That is, if the voltage of the destination system power supply 13 is 200 V AC (effective value), the set value of the predetermined voltage Vak is set to 180 V, for example, in accordance with the standard of the system power supply 13. As a result, the usable area of the power supply device 11 is widened, and high versatility can be provided.

  In addition, since the predetermined current Ik can be freely set, for example, when the power supply device 11 is produced, even if products with different specifications of the bidirectional inverter 17 and the power storage unit 19 are manufactured on the same line, according to the specifications. The predetermined current Ik for monitoring the overcurrent can be easily set.

  Further, since the predetermined power storage unit voltage Vbk can be freely set, for example, when the power supply device 11 is produced, even if products with different specifications of the full charge voltage of the power storage unit 19 are manufactured on the same line, according to the specification. Thus, the predetermined power storage unit voltage Vbk for monitoring the overvoltage can be easily set.

  A plurality of these three parameters (predetermined voltage Vak, predetermined current Ik, predetermined power storage unit voltage Vbk) may be included in variable signal K at the same time. In this case, a plurality of parameters can be set collectively.

  Here, if at least one of the predetermined voltage Vak, the predetermined current Ik, or the predetermined power storage unit voltage Vbk is changed while the power supply device 11 is in use, an overcurrent may flow depending on the set value, or the operation of the bidirectional inverter 17 may not be performed. Since there is a possibility of being stable, it is desirable to change the parameter by the variable signal K before starting the power supply device 11.

  Operations other than the above are the same as those in the second embodiment.

  In the configuration of FIG. 5, the power storage unit voltage detection unit 37 is provided. However, the configuration and operation that characterize the third embodiment may be applied to the configuration of FIG.

  That is, the power supply device 11 further includes an external device terminal 43 that electrically connects the control unit 23 and the external device 41 to the configuration of FIG. Then, the control unit 23 sets at least one of the predetermined voltage Vak or the predetermined current Ik according to the variable signal K from the external device 41 input from the external device terminal 43.

  With such a configuration and operation, the predetermined voltage Vak can be freely set by the variable signal K of the external device 41. Therefore, when the power supply device 11 is used in an area where the standard of the system power supply 13 is different. Very easily, the predetermined voltage Vak can be set according to the power situation in the area. Further, since the predetermined current Ik can be freely set, the predetermined current Ik for monitoring the overcurrent can be easily set according to the power supply device 11 in which the specifications of the bidirectional inverter 17 and the power storage unit 19 are changed.

  In this configuration, power storage unit voltage detection unit 37 is not provided, so that default power storage unit voltage Vbk is not included in variable signal K.

  With the above configuration and operation, according to the variable signal K of the external device 41, at least one of the predetermined voltage Vak, the predetermined current Ik, or the predetermined power storage unit voltage Vbk can be freely set. When the power supply device 11 is used in an area with different standards, the power supply apparatus 11 capable of setting the predetermined voltage Vak according to the power situation in the area can be obtained very easily. Also, the overcurrent and overvoltage monitoring set values can be easily changed according to the specifications of the power supply device 11, and high reliability can be obtained.

  In the third embodiment, the case where at least one of the predetermined voltage Vak, the predetermined current Ik, or the predetermined power storage unit voltage Vbk is set by the variable signal K has been described. Control (for example, manual on / off control of the switch 15) may be performed.

  Furthermore, in the third embodiment, the variable signal K shows an example of unidirectional communication from the external device 41 to the control unit 23, but this may be bidirectional communication. In this case, the external device 41 can monitor the abnormality of the power supply device 11 by obtaining, for example, the current and voltage characteristics of each part of the power supply device 11.

(Embodiment 4)
FIG. 6 is a block circuit diagram of a power supply device according to Embodiment 4 of the present invention. FIGS. 7A and 7B are graphs of voltage-current characteristics of the power supply device according to Embodiment 4 of the present invention. FIG. 7A is a time-dependent characteristic diagram of the system power supply side voltage Vi, and FIG. 7B is a time-dependent characteristic of the DC / DC converter side voltage Vd. FIG. 4C is a time characteristic diagram of the power storage unit voltage Vb, and FIG. 4D is a time characteristic diagram of the current I flowing through the power storage unit.

  In the configuration of the fourth embodiment, the same components as those of the first and second embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 6, the power supply device 11 includes a bidirectional inverter 17 electrically connected to the system power supply 13 via the switch 15, a DC / DC converter 51 electrically connected to the bidirectional inverter 17, and a DC / DC Power storage unit 19 electrically connected to DC converter 51. The power supply device 11 is electrically connected to the system power supply side of the bidirectional inverter 17, detects the system power supply side voltage Vi, and the DC / DC converter 51 side of the bidirectional inverter 17. A DC / DC converter side voltage detection unit 55 that detects the DC / DC converter side voltage Vd and a power storage unit voltage detection unit that is electrically connected to the power storage unit 19 and detects the power storage unit voltage Vb. 37 and a current detection unit 22 that detects a current I flowing through the power storage unit 19. The power supply device 11 includes a switch 15, a bidirectional inverter 17, a DC / DC converter 51, a system power supply side voltage detection unit 53, a DC / DC converter side voltage detection unit 55, a power storage unit voltage detection unit 37, and a current detection unit. And a control unit 23 electrically connected to the control unit 22. In the operation of the bidirectional inverter 17 of the power supply device 11, the control unit 23 maintains the DC / DC converter side voltage Vd when the DC / DC converter side voltage Vd reaches the first predetermined DC / DC converter side voltage Vdk 1. Control to maintain the current I if the DC / DC converter side voltage Vd does not reach the first predetermined DC / DC converter side voltage Vdk1 and the current I reaches the predetermined current Ik. If the DC / DC converter side voltage Vd does not reach the first predetermined DC / DC converter side voltage Vdk1 and the current I does not reach the predetermined current Ik, the system power supply side voltage Vi is The control is performed with the third priority so that the predetermined system power supply side voltage Vik is lower than the specified lower limit voltage Vad of the system power supply. At the same time, in the operation of the DC / DC converter 51 of the power supply device 11, when the power storage unit voltage Vb reaches the predetermined power storage unit voltage Vbk, the control unit 23 performs control to maintain the power storage unit voltage Vb with first priority. If the power storage unit voltage Vb does not reach the predetermined power storage unit voltage Vbk, the DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2 lower than the first predetermined DC / DC converter side voltage Vdk1. Control is performed with the second priority. At the same time, the control unit 23 of the power supply device 11 performs the operation of the bidirectional inverter 17 and the operation of the DC / DC converter 51 in parallel, and turns off the switch 15 when the power storage unit 19 is discharged. Time is controlled to turn on the switch 15.

  Accordingly, when the current I becomes lower than the predetermined current Ik and the system power supply side voltage Vi becomes lower than the predetermined system power supply side voltage Vik due to the occurrence of a power failure or the like, the bidirectional inverter 17 Control is performed to increase the system power supply side voltage Vi so that Vi becomes the predetermined system power supply side voltage Vik. As a result, the bidirectional inverter 17 operates to draw the current I from the DC / DC converter 51. As a result, since the DC / DC converter side voltage Vd is lowered, the DC / DC converter 51 is configured so that the second priority DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2. Control is performed to increase the DC converter side voltage Vd. Thereby, the DC / DC converter 51 operates to draw the current I from the power storage unit 19, that is, to discharge the power storage unit 19. In these series of operations, the bidirectional inverter 17 continues the control so that the system power supply side voltage Vi becomes the predetermined system power supply side voltage Vik, and in parallel with this, the DC / DC converter 51 operates as a DC / DC converter. Control is continued such that the side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2. As a result, the charging and discharging of the power storage unit 19 is smoothly performed in conjunction with the magnitude of the system power supply side voltage Vi without performing any special switching operation for the bidirectional inverter 17 and the DC / DC converter 51. Is called. Therefore, the power supply device 11 can be obtained that can stably supply power to the load 29 even when the system power supply side voltage Vi decreases during charging of the power storage unit 19.

  Hereinafter, the characteristic features of the configuration and operation of the fourth embodiment will be described more specifically.

  In FIG. 6, the system power supply 13 is electrically connected to the bidirectional inverter 17 of the power supply device 11 via the switch 15. Specifically, the system power supply 13 is electrically connected to the system power supply side terminal 57 and the system power supply side ground terminal 59 of the bidirectional inverter 17. The system power supply side voltage detection unit 53 is electrically connected to the system power supply side terminal 57 and the system power supply side ground terminal 59.

  Comparing the above description with FIG. 1, the input / output terminal 25, the input / output ground terminal 27, and the input / output voltage detection unit 21 in FIG. 1 are respectively connected to the system power supply side terminal 57 and the system power supply side ground terminal in FIG. 59, corresponding to the system power supply side voltage detection unit 53. However, in the fourth embodiment, in the bidirectional inverter 17, since there are simply two “input / output terminals”, the names are changed in order to distinguish these terminals. Therefore, the system power supply side terminal 57, the system power supply side ground terminal 59, and the system power supply side voltage detection unit 53 of the fourth embodiment are respectively the input / output terminal 25, the input / output ground terminal 27, and the input / output voltage of the first embodiment. This is substantially the same as the detection unit 21.

  The bidirectional inverter 17 is electrically connected to the DC / DC converter 51 via a DC / DC converter side terminal 60 and a DC / DC converter side ground terminal 61. The DC / DC converter side voltage detection unit 55 is electrically connected to the DC / DC converter side terminal 60 and the DC / DC converter side ground terminal 61. The DC / DC converter side voltage detector 55 detects the voltage between the bidirectional inverter 17 and the DC / DC converter 51, as is apparent from FIG. Although it is connected to the converter side terminal 60 and the DC / DC converter side ground terminal 61, it is not limited to this configuration, and may be connected to a terminal (not shown) on the DC / DC converter 51 side. The intermediate wiring may be connected.

  DC / DC converter 51 is further electrically connected to power storage unit 19 via power storage unit side terminal 63 and power storage unit side ground terminal 65. Thereby, it becomes possible to charge / discharge the electrical storage part 19 in a wide voltage range. That is, the voltage output to the power storage unit 19 side of the bidirectional inverter 17 can only be boosted, but by providing the DC / DC converter 51, the power storage unit 19 can be charged / discharged without being limited to the boosted voltage. Therefore, the design range of the power storage unit 19 is widened, and the configuration of the minimum necessary power storage unit 19 can be achieved. As a result, for example, the number of capacitors of the capacitor unit can be designed with the minimum necessary quantity, so that the cost and weight can be reduced.

  In addition, since the DC / DC converter 51 can use an insulation type DC / DC converter using a transformer in the circuit configuration, when insulation is required to handle a high voltage of about 200 V as in the fourth embodiment. In addition, insulation can be obtained by the DC / DC converter 51.

  Further, the DC / DC converter 51 may be a chopper type.

  The power storage unit voltage detection unit 37 is electrically connected to the power storage unit side terminal 63 and the power storage unit side ground terminal 65. This power storage unit voltage detection unit 37 has the same configuration as that of the second embodiment. In the fourth embodiment, since charging / discharging can be performed in a wide voltage range as described above, monitoring of power storage unit voltage Vb is essential. Therefore, the power storage unit voltage detection unit 37 is necessary.

  The system power supply side voltage detection unit 53 and the DC / DC converter side voltage detection unit 55 are also electrically connected to the control unit 23. Therefore, the control unit 23 can take in the system power supply side voltage Vi and the DC / DC converter side voltage Vd. Further, the DC / DC converter 51 is also electrically connected to the control unit 23. Therefore, the DC / DC converter 51 is controlled by the DC / DC converter control signal CC from the control unit 23.

  The configuration other than the above is the same as in the first and second embodiments. In the configuration of FIG. 6, the configuration in which the current detection unit 22 is provided in the wiring between the DC / DC converter-side ground terminal 61 and the DC / DC converter 51 is shown. 19 may be provided on the positive electrode side wiring, or may be provided on the positive electrode side wiring between the bidirectional inverter 17 and the DC / DC converter 51. Further, the current detection unit 22 may be provided in a portion where a current corresponding to the current I flowing in the power storage unit 19 flows inside the bidirectional inverter 17 or the DC / DC converter 51.

  Next, the operation of such a power supply device 11 will be described.

  First, since the bidirectional inverter 17 and the DC / DC converter 51 operate in parallel with priority, the priority relationships are summarized below. The control unit 23 controls these operations.

1) Bidirectional inverter First priority: Control that maintains DC / DC converter side voltage Vd when DC / DC converter side voltage Vd reaches first predetermined DC / DC converter side voltage Vdk1 Second priority: DC / DC converter If the side voltage Vd does not reach the first predetermined DC / DC converter side voltage Vdk1 and the current I reaches the predetermined current Ik, the control to maintain the current I. Third priority: The DC / DC converter side voltage Vd is the first. 1 If the predetermined DC / DC converter side voltage Vdk1 is not reached and the current I does not reach the predetermined current Ik, the system power supply side voltage Vi is lower than the specified lower limit voltage Vad of the system power supply 13 2) DC / DC converter First priority: If the storage battery voltage Vb reaches the default storage battery voltage Vbk, the storage battery voltage Vb is maintained. Control second priority: If the storage unit voltage Vb does not reach the predetermined storage unit voltage Vbk, the second predetermined DC / DC converter in which the DC / DC converter side voltage Vd is lower than the first predetermined DC / DC converter side voltage Vdk1. Control so as to be the side voltage Vdk2 According to the above priority order, the control unit 23 controls the bidirectional inverter 17 and the DC / DC converter 51 independently and in parallel.

  Next, specific operations based on such priorities will be described with reference to FIG. In FIGS. 7A to 7D, the horizontal axis indicates time. Further, the vertical axis in FIG. 7A represents the system power supply side voltage Vi, the vertical axis in FIG. 7B represents the DC / DC converter side voltage Vd, and the vertical axis in FIG. 7C represents the storage unit voltage Vb. The vertical axis in FIG. 7D shows the current I.

  Further, the situation that occurs from time t0 to time t3 in FIG. 7 is the same as in FIG. That is, the power storage unit 19 is charged from time t0 to time t1, a power failure occurs at time t1, and the power failure is restored at time t2, and the power storage unit voltage Vb reaches the predetermined power storage unit voltage Vbk at time t3. Become charged.

  The following description will focus on how the bidirectional inverter 17 and the DC / DC converter 51 operate in accordance with the above-described priorities in such a situation.

  First, from time t0 to time t1, the power storage unit 19 is being charged. At this time, it is assumed that the system power supply side voltage Vi is normal at exactly 100 V between the specified upper limit voltage Vau (106 V as in the first embodiment) and the specified lower limit voltage Vad (94 V).

  In this case, as described in the first embodiment, the bidirectional inverter 17 has a predetermined system power supply side voltage Vik whose system power supply side voltage Vi is lower than the specified lower limit voltage Vad of the system power supply 13 (here, in the first embodiment). The bidirectional power supply 17 is controlled so as to reduce the system power supply side voltage Vi so as to be 90 V which is the same as the predetermined voltage Vak). For this purpose, the bidirectional inverter 17 performs an operation of drawing the current I to the DC / DC converter 51 side. . As a result, since the current I immediately reaches the predetermined current Ik, the control unit 23 maintains the current I as the predetermined current Ik as shown in FIG. 7D according to the second priority control of the bidirectional inverter 17 described above. Control to do. As described above, since the current I is constant at the predetermined current Ik, the third priority control of the bidirectional inverter 17 is not performed, and the system power supply side voltage Vi remains constant at 100V as shown in FIG. It becomes.

  Here, from the above priority order, the control unit 23 maintains the DC / DC converter side voltage Vd when the DC / DC converter side voltage Vd of the bidirectional inverter 17 reaches the first predetermined DC / DC converter side voltage Vdk1. In the fourth embodiment, the first predetermined DC / DC converter side voltage Vdk1 is set to 210V, for example. This voltage value is output by rectifying and boosting a voltage of AC 100 V (effective value) by the bidirectional inverter 17. In the fourth embodiment, as the specification of the bidirectional inverter 17, an effective AC input voltage is obtained. Is multiplied by 2.1 to output DC conversion. Therefore, the bidirectional inverter 17 is monitored by the control unit 23 so as not to become an overvoltage higher than the first predetermined DC / DC converter side voltage Vdk1 (210V). This monitoring operation is the first priority control of the bidirectional inverter 17.

  Based on such priorities, looking at the operation from time t0 to time t1, the bidirectional inverter 17 has already given the second priority so that the current I becomes the predetermined current Ik as shown in FIG. Therefore, the first priority control is not performed. This is because even when the current I is supplied up to the predetermined current Ik, as shown in FIG. 7C, the power storage unit voltage Vb rises with time and the power storage unit 19 continues to be charged. This is because Vd does not reach the first predetermined DC / DC converter side voltage Vdk1. As a result, the first priority control of the bidirectional inverter 17 is not performed from the time t0 to the time t1.

  On the other hand, looking at the operation of DC / DC converter 51 from time t0 to time t1, power storage unit voltage Vb does not reach default power storage unit voltage Vbk because charging is in progress from FIG. Therefore, the first priority control of the DC / DC converter 51 is not performed. Therefore, the second priority control is performed such that the DC / DC converter side voltage Vd reaches the second predetermined DC / DC converter side voltage Vdk2 lower than the first predetermined DC / DC converter side voltage Vdk1.

  Here, the second predetermined DC / DC converter side voltage Vdk2 is different from the DC / DC converter side voltage Vd depending on the bidirectional inverter 17 while the second priority control or the third priority control of the bidirectional inverter 17 is performed. By setting the second predetermined DC / DC converter side voltage Vdk2 with a voltage determined with respect to being not controlled, the possibility that the DC / DC converter side voltage Vd becomes an overvoltage is reduced. Specifically, the second predetermined DC / DC converter side voltage Vdk2 is set to 200 V, which is lower than the first predetermined DC / DC converter side voltage Vdk1 (210V). Thereby, when the bidirectional inverter 17 does not control the DC / DC converter side voltage Vd at all, the control unit 23 sets the DC / DC converter side voltage Vd to the second predetermined DC / DC converter side voltage Vdk2 (200V). Thus, the DC / DC converter 51 is controlled. At this time, since the DC / DC converter 51 does not control with the current I, a constant current of the predetermined current Ik flows through the DC / DC converter 51. As a result, the power storage unit 19 is charged with reduced possibility of overvoltage and overcurrent.

  The second predetermined DC / DC converter side voltage Vdk2 is set to be lower than the first predetermined DC / DC converter side voltage Vdk1, but if this is reversed, the first priority control of the bidirectional inverter 17 is performed. As a result, the current I to the power storage unit 19 is not controlled at all. As a result, current I may be lower than predetermined current Ik, and the charging period of power storage unit 19 may be extended. Therefore, the second predetermined DC / DC converter side voltage Vdk2 needs to be set lower than the first predetermined DC / DC converter side voltage Vdk1.

  As described above, a power failure occurs at time t1 while the power storage unit 19 is being charged. As a result, the current I to the power storage unit 19 does not flow, so that the current I becomes lower than the predetermined current Ik and deviates from the second priority control condition of the bidirectional inverter 17. Accordingly, the bidirectional inverter 17 is subjected to the third priority control. That is, as shown in FIG. 7A, the control unit 23 performs control so that the system power supply side voltage Vi becomes the predetermined system power supply side voltage Vik (90 V). As a result, the bidirectional inverter 17 operates to draw the current I from the DC / DC converter 51. In conjunction with this operation, the DC / DC converter 51 operates to discharge the power storage unit 19, and the power storage unit voltage Vb decreases with time as shown in FIG. Therefore, as shown in FIG. 7D, the current I is negative, and the absolute value thereof is a value corresponding to the consumption current of the load 29.

  As a result of this operation, power storage unit voltage Vb decreases with time due to discharge, so power storage unit voltage Vb does not reach predetermined power storage unit voltage Vbk. Accordingly, the DC / DC converter 51 continues the second priority control from time t1 to time t2. Therefore, the DC / DC converter 51 can perform discharging from charging at time t1 without performing any switching operation. As shown in FIG. 7B, the DC / DC converter side voltage Vd is stabilized at the second predetermined DC / DC converter side voltage Vdk2 (200 V) even during the discharge of the power storage unit 19. Note that the switching operation from charging to discharging of the bidirectional inverter 17 is not performed as described in the first embodiment, so that the switching can be performed smoothly.

  Next, the power failure returns at time t2. Since the state at this time is the same as the state from time t0 to time t1, the operation from time t0 to time t1 is performed. Therefore, detailed description is omitted.

  Next, at time t3, as shown in FIG. 7C, power storage unit voltage Vb reaches predetermined power storage unit voltage Vbk. Since this corresponds to the power storage unit 19 being fully charged, the first priority control is performed in order for the DC / DC converter 51 not to overcharge the power storage unit 19. That is, control unit 23 controls DC / DC converter 51 such that power storage unit voltage Vb becomes predetermined power storage unit voltage Vbk.

  As a result, since the power storage unit 19 is no longer charged, the current I rapidly decreases and becomes almost zero as shown in FIG. As a result of such an operation, the bidirectional inverter 17 that has been subjected to the second priority control (control so that the current I becomes the predetermined current Ik) until now has the second priority because the current I is lower than the predetermined current Ik. From the control, the third priority control (control so that the system power supply side voltage Vi becomes the predetermined system power supply side voltage Vik) is performed. In this case, as shown in FIG. 7A, since the system power supply side voltage Vi is the specified upper limit voltage Vau (106V), in order to lower the system power supply side voltage Vi, the bidirectional inverter 17 converts the current I to DC / Attempt to pull to DC converter 51 side. However, as described above, the DC / DC converter 51 performs the first priority control such that the power storage unit voltage Vb maintains the predetermined power storage unit voltage Vbk, and therefore cannot pass the current I. As a result, as shown in FIG. 7 (b), at time t3, the DC / DC converter side voltage Vd increases rapidly and reaches the first predetermined DC / DC converter side voltage Vdk1.

  Thereby, since the bidirectional inverter 17 has reached the first priority control condition, as shown in FIG. 7B, the DC / DC converter side voltage Vd becomes the first predetermined DC / DC converter side voltage Vdk1. Be controlled. As a result, after time t3, the DC / DC converter side voltage Vd maintains the first predetermined DC / DC converter side voltage Vdk1.

  Such an operation enables smooth switching in the DC / DC converter 51 in addition to the smooth switching of the bidirectional inverter 17 described in the first embodiment in charging and discharging of the power storage unit 19. Also in the power supply device 11 including the DC converter 51, it is possible to smoothly switch charging / discharging of the power storage unit 19 as a whole.

  The key point in this smooth charge / discharge switching operation is that the third priority control in the bidirectional inverter 17 (the system power supply side voltage Vi becomes a predetermined system power supply side voltage Vik that is lower than the specified lower limit voltage Vad of the system power supply 13). Control) and second priority control in the DC / DC converter 51 (the DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2 lower than the first predetermined DC / DC converter side voltage Vdk1). Control). Both operations are performed by using the terminal voltage of the bidirectional inverter 17 and the DC / DC converter 51 on the side far from the power storage unit 19 as the steady-state voltage (the specified lower limit voltage Vad and the first predetermined DC / DC converter side, respectively). By controlling so as to be lower than the voltage Vdk1), the control unit 23 is in a state where the control at the time of discharging the power storage unit 19 is in a standby state. Therefore, even if a power failure occurs during charging, charging / discharging can be smoothly switched.

  Furthermore, since the control of the bidirectional inverter 17 and the control of the DC / DC converter 51 are performed independently and in parallel, a high-speed switching operation is possible. As a result, the power supply device 11 can stably supply power to the load 29 even when the system power supply voltage Vi decreases during charging of the power storage unit 19.

  In the above description of the operation, the operation of taking in the system power supply voltage Vs from the system voltage detection unit 32 and the control of the switch 15 are the same as those in the first embodiment, and thus are omitted.

  With the above configuration and operation, in addition to the bidirectional inverter 17 described in the first embodiment, the DC / DC converter 51 that charges and discharges the power storage unit 19 is connected to the second inverter 17 in the bidirectional inverter 17 by the control unit 23. The operation from the first priority to the third priority operation (including the monitoring of the current I) and the first priority operation to the second priority operation in the DC / DC converter 51 are performed in parallel. Similarly to the inverter 17, the DC / DC converter 51 also smoothly charges and discharges the power storage unit 19 without performing a special switching operation. Therefore, it is possible to realize the power supply device 11 that can stably supply power to the load 29 even when the system power supply voltage Vi decreases during charging of the power storage unit 19.

(Embodiment 5)
8A and 8B are graphs of voltage-current aging characteristics of the power supply device according to Embodiment 5 of the present invention. FIG. 8A is a time-dependent characteristic diagram of the system power supply side voltage Vi, and FIG. 8B is a time-dependent characteristic of the DC / DC converter side voltage Vd. FIG. 4C is a time characteristic diagram of the power storage unit voltage Vb, and FIG. 4D is a time characteristic diagram of the current I flowing through the power storage unit.

  The configuration of the fifth embodiment is the same as FIG. 6 of the fourth embodiment.

  That is, in FIG. 6, the power supply device 11 includes a bidirectional inverter 17 that is electrically connected to the system power supply 13 via the switch 15, a DC / DC converter 51 that is electrically connected to the bidirectional inverter 17, And a power storage unit 19 electrically connected to the DC / DC converter 51. The power supply device 11 is electrically connected to the system power supply side of the bidirectional inverter 17, detects the system power supply side voltage Vi, and the DC / DC converter 51 side of the bidirectional inverter 17. A DC / DC converter side voltage detection unit 55 that detects the DC / DC converter side voltage Vd and a power storage unit voltage detection unit that is electrically connected to the power storage unit 19 and detects the power storage unit voltage Vb. 37 and a current detection unit 22 that detects a current I flowing through the power storage unit 19. The power supply device 11 includes a switch 15, a bidirectional inverter 17, a DC / DC converter 51, a system power supply side voltage detection unit 53, a DC / DC converter side voltage detection unit 55, a power storage unit voltage detection unit 37, and a current detection unit. And a control unit 23 electrically connected to the control unit 22.

  In the operation of the bidirectional inverter 17 of the power supply device 11, the control unit 23 maintains the DC / DC converter side voltage Vd when the DC / DC converter side voltage Vd reaches the first predetermined DC / DC converter side voltage Vdk 1. If the DC / DC converter side voltage Vd does not reach the first predetermined DC / DC converter side voltage Vdk1, the system power supply side voltage Vi is higher than the specified lower limit voltage Vad of the system power supply 13. Control with a low predetermined system power supply side voltage Vik is performed with the second priority. At the same time, in the operation of DC / DC converter 51, when power storage unit voltage Vb reaches predetermined power storage unit voltage Vbk, control unit 23 performs control to maintain power storage unit voltage Vb with first priority, and power storage unit voltage Vb. Does not reach the predetermined power storage unit voltage Vbk, and if the current I reaches the predetermined current Ik, control for maintaining the current I is performed with the second priority, and the power storage unit voltage Vb does not reach the predetermined power storage unit voltage Vbk. If the current I does not reach the predetermined current Ik, the DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2 lower than the first predetermined DC / DC converter side voltage Vdk1. Control is performed with the third priority. At the same time, the control unit 23 performs the operation of the bidirectional inverter 17 and the operation of the DC / DC converter 51 in parallel, and turns off the switch 15 when the power storage unit 19 is discharged. Is controlled to turn on.

  Thereby, when the current I becomes lower than the predetermined current Ik and the system power supply side voltage Vi becomes lower than the predetermined system power supply side voltage Vik due to the occurrence of a power failure or the like, the bidirectional inverter 17 Control is performed to increase the system power supply side voltage Vi so that Vi becomes the predetermined system power supply side voltage Vik. As a result, the bidirectional inverter 17 operates to draw the current I from the DC / DC converter 51. As a result, the DC / DC converter side voltage Vd is lowered, so that the DC / DC converter 51 has a third priority, the second predetermined DC whose DC / DC converter side voltage Vd is lower than the first predetermined DC / DC converter side voltage Vdk1. Control is performed to increase the DC / DC converter side voltage Vd so as to be the DC / DC converter side voltage Vdk2. Thereby, the DC / DC converter 51 operates to draw the current I from the power storage unit 19, that is, to discharge the power storage unit 19. In these series of operations, the bidirectional inverter 17 continues the control so that the system power supply side voltage Vi becomes the predetermined system power supply side voltage Vik, and in parallel with this, the DC / DC converter 51 operates as a DC / DC converter. Control is continued such that the side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2. As a result, the charging and discharging of the power storage unit 19 is smoothly performed in conjunction with the magnitude of the system power supply side voltage Vi without performing any special switching operation for the bidirectional inverter 17 and the DC / DC converter 51. Is called. Therefore, the power supply device 11 can be obtained that can stably supply power to the load 29 even when the system power supply side voltage Vi decreases during charging of the power storage unit 19.

  Hereinafter, the characteristic features of the configuration and operation of the fifth embodiment will be described more specifically.

  First, the configuration of the power supply device 11 according to the fifth embodiment is the same as that of the fourth embodiment shown in FIG.

  Next, operations that are characteristic of the power supply device 11 according to the fifth embodiment will be described. In the operation of the fifth embodiment, detailed description of the same operation as that of the fourth embodiment is also omitted.

  The operation of the fifth embodiment differs from the operation of the fourth embodiment in that the current I is monitored based on the comparison between the current I and the predetermined current Ik by the bidirectional inverter 17 in the fourth embodiment. In the fifth embodiment, the current I is monitored by the DC / DC converter 51 instead of the bidirectional inverter 17. As a result, the priority of control in the bidirectional inverter 17 and the DC / DC converter 51 changes as follows.

1) Bidirectional inverter First priority: Control that maintains DC / DC converter side voltage Vd when DC / DC converter side voltage Vd reaches first predetermined DC / DC converter side voltage Vdk1 Second priority: DC / DC converter If the side voltage Vd does not reach the first predetermined DC / DC converter side voltage Vdk1, control is performed so that the system power supply side voltage Vi becomes a predetermined system power supply side voltage Vik lower than the specified lower limit voltage Vad of the system power supply 13. ) DC / DC converter 1st priority: Control to maintain power storage unit voltage Vb if power storage unit voltage Vb reaches default power storage unit voltage Vbk Second priority: Power storage unit voltage Vb does not reach default power storage unit voltage Vbk If current I reaches predetermined current Ik, control to maintain current I Third priority: power storage unit voltage Vb does not reach predetermined power storage unit voltage Vbk, and If I does not reach the predetermined current Ik, control is performed so that the DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2 lower than the first predetermined DC / DC converter side voltage Vdk1. According to the order, the control unit 23 controls the bidirectional inverter 17 and the DC / DC converter 51 independently and in parallel.

  Next, a specific operation based on such priorities will be described with reference to FIG. The meanings of the vertical and horizontal axes in FIGS. 8A to 8D are the same as those in FIGS. 7A to 7D, respectively. Further, the situation that occurs from time t0 to time t3 in FIG. 8 is the same as in FIG.

  The following description will focus on how the bidirectional inverter 17 and the DC / DC converter 51 operate in accordance with the above-described priorities in such a situation.

  First, from time t0 to time t1, the system power supply 13 is normal and the power storage unit 19 is being charged. At this time, as in the fourth embodiment, the bidirectional inverter 17 draws the current I toward the DC / DC converter 51, and as a result, the current I reaches the predetermined current Ik as shown in FIG.

  Here, in the fourth embodiment, the bidirectional inverter 17 controls the current I to be maintained at the predetermined current Ik. However, in the fifth embodiment, as described above, the predetermined current I is controlled. The maintenance control with the current Ik is performed by the DC / DC converter 51. Therefore, according to the second priority control of the DC / DC converter 51 described above, the control unit 23 controls the DC / DC converter 51 so that the current I becomes the predetermined current Ik.

  As a result, in the fourth embodiment, the DC / DC converter side voltage Vd is controlled by the DC / DC converter 51. However, in the fifth embodiment, since the control has the third priority, from the time t0 to the time t1. Up to this point, the DC / DC converter 51 does not control the DC / DC converter side voltage Vd. Therefore, the bidirectional inverter 17 tries to draw the current I to the DC / DC converter 51 side, but since the current I is limited by the predetermined current Ik by the DC / DC converter 51, the DC / DC converter side voltage Vd rises. Then, it immediately reaches the first predetermined DC / DC converter side voltage Vdk1. At this stage, since the condition for performing the first priority control of the bidirectional inverter 17 is established, the bidirectional inverter 17 performs control so that the DC / DC converter side voltage Vd becomes the first predetermined DC / DC converter side voltage Vdk1. . Accordingly, as shown in FIG. 8B, the DC / DC converter side voltage Vd becomes the first predetermined DC / DC converter side voltage Vdk1.

  Note that during the period from time t0 to time t1, as in the fourth embodiment, control is not performed so that the DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2. This is because the DC / DC converter 51 has already performed the second priority control (maintaining the current I at the predetermined current Ik), and the DC / DC converter side voltage Vd is maintained at the second predetermined DC / DC converter side voltage Vdk2. This is because control cannot be performed.

  To summarize these operations, during the charging period of the power storage unit 19 from time t0 to time t1, the DC / DC converter 51 monitors the overcurrent of the current I, and the bidirectional inverter 17 monitors the overvoltage. .

  Next, a power failure occurs at time t1. As a result, the current I to the power storage unit 19 rapidly decreases, so that the current I becomes lower than the predetermined current Ik and deviates from the second priority control condition of the DC / DC converter 51. At this time, as shown in FIG. 8C, the power storage unit voltage Vb has not reached the predetermined power storage unit voltage Vbk, and thus the DC / DC converter 51 is subjected to the third priority control. As a result, as shown in FIG. 8 (b), the DC / DC converter side voltage Vd has a second predetermined DC / DC converter side voltage Vdk2 (200V) lower than the first predetermined DC / DC converter side voltage Vdk1 (210V). Controlled to maintain.

  On the other hand, in the bidirectional inverter 17, since the current I sharply decreases due to a power failure, the first priority control (the DC / DC converter side voltage Vd is maintained at the first predetermined DC / DC converter side voltage Vdk1). Control) cannot be continued. Therefore, the control unit 23 controls the bidirectional inverter 17 such that the system power supply side voltage Vi, which is the second priority control, becomes the predetermined system power supply side voltage Vik (90 V). As a result, as shown in FIG. 8A, the system power supply side voltage Vi is maintained at the predetermined system power supply side voltage Vik from time t1 to time t2 during a power failure. With such an operation, the bidirectional inverter 17 operates to draw the current I from the DC / DC converter 51 in order to maintain the system power supply side voltage Vi at the predetermined system power supply side voltage Vik. In conjunction with this operation, the DC / DC converter 51 operates to discharge the power storage unit 19, and the power storage unit voltage Vb decreases with time as shown in FIG. The current I discharged from the power storage unit 19 is supplied to the load 29. Since power storage unit 19 is discharged, the sign of current I to load 29 is negative. Then, as shown in FIG. 8D, the current I to the load 29 flows as much as the consumption current that does not reach the maximum current (lower limit current −Id) that discharges the power storage unit 19, and is shown in FIG. 8C. Thus, power storage unit voltage Vb does not reach predetermined power storage unit voltage Vbk. Therefore, the DC / DC converter 51 performs the third priority control from time t1 to time t2.

  As described above, the DC / DC converter 51 performs the second priority control (maintaining the current I at the predetermined current Ik) until immediately before the power failure occurs at the time t1, but in parallel with this, the second priority control is performed. Since the operation is performed so that the third priority control can be performed immediately when the above condition is removed, the DC / DC converter 51 can perform the third priority control immediately when a power failure occurs at time t1. it can. As a result, the DC / DC converter 51 can perform discharging from charging at time t1 without performing a special switching operation. Note that the switching operation from charging to discharging of the bidirectional inverter 17 is not performed as described in the first embodiment, so that the switching can be performed smoothly.

  Next, the power failure returns at time t2. Since the state at this time is the same as the state from time t0 to time t1, the operation from time t0 to time t1 is performed. Therefore, detailed description is omitted.

  Next, at time t3, as shown in FIG. 8C, power storage unit voltage Vb reaches predetermined power storage unit voltage Vbk. As in the fourth embodiment, the first priority control (maintaining power storage unit voltage Vb at predetermined power storage unit voltage Vbk) is performed so that DC / DC converter 51 does not overcharge power storage unit 19 as in the fourth embodiment.

  As a result, the second priority control (maintaining the current I at the predetermined current Ik) of the DC / DC converter 51 performed until the time t3 is not performed after the time t3. On the other hand, since the bidirectional inverter 17 has already been subjected to the first priority control (maintaining the DC / DC converter side voltage Vd at the first predetermined DC / DC converter side voltage Vdk1) until the time t3. Continue that control.

  Such an operation enables smooth switching in the DC / DC converter 51 in addition to the smooth switching of the bidirectional inverter 17 described in the first embodiment in charging and discharging of the power storage unit 19. Therefore, even in the power supply device 11 including the DC / DC converter 51 and configured to monitor the current I by the DC / DC converter 51, the charging / discharging of the power storage unit 19 can be smoothly switched as a whole.

  The essential point in this smooth charge / discharge switching operation is that the second priority control in the bidirectional inverter 17 (the system power supply side voltage Vi becomes a predetermined system power supply side voltage Vik lower than the specified lower limit voltage Vad of the system power supply 13). Control) and third priority control in the DC / DC converter 51 (the DC / DC converter side voltage Vd becomes the second predetermined DC / DC converter side voltage Vdk2 lower than the first predetermined DC / DC converter side voltage Vdk1). Control). As a result, as described in the fourth embodiment, the control unit 23 is in a state where the control at the time of discharging the power storage unit 19 is on standby. Therefore, even if a power failure occurs during charging, charging / discharging can be smoothly switched.

  Further, as in the fourth embodiment, since control of bidirectional inverter 17 and control of DC / DC converter 51 are performed independently and in parallel, a high-speed switching operation is possible. As a result, the power supply device 11 can stably supply power to the load 29 even when the system power supply voltage Vi decreases during charging of the power storage unit 19.

  In the above description of the operation, the operation of taking in the system power supply voltage Vs from the system voltage detection unit 32 and the control of the switch 15 are the same as those in the first embodiment, and thus are omitted.

  With the above configuration and operation, in addition to the bidirectional inverter 17 described in the first embodiment, the DC / DC converter 51 that charges and discharges the power storage unit 19 is connected to the second inverter 17 in the bidirectional inverter 17 by the control unit 23. A bidirectional operation is performed in parallel from the first priority operation to the second priority operation and from the first priority operation to the third priority operation (including monitoring of the current I) in the DC / DC converter 51. Similarly to the inverter 17, the DC / DC converter 51 also smoothly charges and discharges the power storage unit 19 without performing a special switching operation. Therefore, it is possible to realize the power supply device 11 that can stably supply power to the load 29 even when the system power supply voltage Vi decreases during charging of the power storage unit 19.

  In the fourth and fifth embodiments, the bidirectional inverter 17 and the DC / DC converter 51 are controlled in accordance with the above-described priority order. Therefore, as shown in FIG. 7B and FIG. The DC / DC converter side voltage Vd included in the controlled object is not simultaneously controlled by both.

  Moreover, the various voltage values in Embodiments 4 and 5 are examples, and are not limited to those voltage values, and may be appropriately changed according to the specifications of the power supply device 11.

(Embodiment 6)
FIG. 9 is a block circuit diagram of the power supply device according to the sixth embodiment of the present invention.

  In the configuration of the sixth embodiment, the same components as those of the first to fourth embodiments are denoted by the same reference numerals and description thereof is omitted. That is, the configuration that is a feature of the sixth embodiment is that in FIG. 9, the configuration of FIG. 6 further includes an external device terminal 43 that electrically connects the control unit 23 and the external device 41. . Therefore, the configuration of the sixth embodiment is obtained by combining the configuration of the third embodiment with the configuration of the fourth embodiment.

  Further, the characteristic operation in the sixth embodiment is as follows. In accordance with the variable signal K from the external device 41 input from the external device terminal 43, the control unit 23 is connected to the predetermined system power supply side voltage Vik, the default current Ik, the default power storage unit voltage Vbk, the first default DC / DC converter side. At least one of the voltage Vdk1 or the second predetermined DC / DC converter side voltage Vdk2 is set.

  Thus, the predetermined system power supply side voltage Vik can be freely set by the variable signal K of the external device 41. Here, as described in the fourth embodiment, the predetermined system power supply side voltage Vik corresponds to the predetermined voltage Vak of the first embodiment, so that the value can be set freely as in the third embodiment. Thus, when the power supply device 11 is used in an area where the standard of the system power supply 13 is different, the predetermined system power supply side voltage Vik can be set very easily according to the power situation of the area. Further, by setting the default current Ik and the default power storage unit voltage Vbk freely, the default current Ik for monitoring the overcurrent and the overvoltage can be set according to the power supply device 11 whose specifications have been changed, as in the third embodiment. The predetermined power storage unit voltage Vbk to be monitored can be easily set. In addition, a power supply in which at least one of the specifications of the bidirectional inverter 17 and the DC / DC converter 51 is changed by freely setting the first predetermined DC / DC converter side voltage Vdk1 and the second predetermined DC / DC converter side voltage Vdk2. According to the device 11, the first predetermined DC / DC converter side voltage Vdk1 and the second predetermined DC / DC converter side voltage Vdk2 for monitoring the overvoltage between the bidirectional inverter 17 and the DC / DC converter 51 can be easily set. . In addition, by setting any of the above five parameters at the same time, it is possible to easily set even when the use area and specifications of the power supply device 11 are changed simultaneously.

  As described in the fourth embodiment, the second predetermined DC / DC converter side voltage Vdk2 needs to be set to be lower than the first predetermined DC / DC converter side voltage Vdk1.

  Hereinafter, the details will be described focusing on the characteristic points in the configuration of the sixth embodiment.

  In FIG. 9, the power supply device 11 includes a control unit 23 and an external device terminal 43 that is electrically connected to the external device 41. Since these are the same as those described with reference to FIG.

  The other configuration is the same as that in FIG.

  Next, the operation of such a power supply device 11 will be described.

  A variable signal K for controlling the power supply device 11 is output from the external device 41. The variable signal K is input to the control unit 23 via the external device terminal 43. The variable signal K is set to at least one of a predetermined system power supply side voltage Vik, a predetermined current Ik, a predetermined power storage unit voltage Vbk, a first predetermined DC / DC converter side voltage Vdk1, or a second predetermined DC / DC converter side voltage Vdk2. Data that contains a value. Therefore, the control unit 23 includes the predetermined system power supply side voltage Vik, the predetermined current Ik, the predetermined power storage unit voltage Vbk, the first predetermined DC / DC converter side voltage Vdk1, or the second predetermined DC / DC included in the input variable signal K. The set value of the converter side voltage Vdk2 is fetched and used as a predetermined system power supply side voltage Vik, a predetermined current Ik, a predetermined power storage unit voltage Vbk, a first predetermined DC / DC converter side voltage Vdk1, or a second predetermined DC / DC converter side voltage Vdk2. Set.

  As a result, when the variable signal K includes the predetermined system power supply side voltage Vik, the bidirectional inverter 17 is controlled so that the system power supply side voltage Vi becomes the set predetermined system power supply side voltage Vik. Further, when the variable signal K includes the predetermined current Ik, the bidirectional inverter 17 is controlled so that the current I becomes the set predetermined current Ik. Further, DC / DC converter 51 is controlled such that power storage unit voltage Vb becomes set default power storage unit voltage Vbk if variable signal K includes predetermined power storage unit voltage Vbk. In addition, if the variable signal K includes the first predetermined DC / DC converter side voltage Vdk1, the bidirectional inverter 17 uses the set first predetermined DC / DC converter side voltage as the DC / DC converter side voltage Vd. It is controlled to be Vdk1. Further, if the second predetermined DC / DC converter side voltage Vdk2 is included in the variable signal K, the DC / DC converter 51 determines that the DC / DC converter side voltage Vd is set to the second predetermined DC / DC converter side. The voltage is controlled to be Vdk2. Note that the priority of these controls is as described in the fourth embodiment.

  Since the predetermined system power supply side voltage Vik can be arbitrarily varied, as described in the third embodiment, for example, if the power supply device 11 is portable, it can be changed to a set value according to the power situation of the destination. . As a result, the usable area of the power supply device 11 is widened, and high versatility can be provided.

  Further, since the predetermined current Ik can be freely set, as described in the third embodiment, the predetermined current Ik for monitoring the overcurrent can be easily set according to the specifications of the bidirectional inverter 17 and the power storage unit 19. Can be set.

  Further, since the default power storage unit voltage Vbk can be set freely, as described in the third embodiment, even if the specification of the full charge voltage of the power storage unit 19 is different, overvoltage is monitored according to the specification. The predetermined power storage unit voltage Vbk to be set can be easily set.

  In addition, since the first predetermined DC / DC converter side voltage Vdk1 can be freely set, for example, the same production line is manufactured with at least one of the bidirectional inverter 17 and the DC / DC converter 51 having different specifications. However, according to the specifications, the first predetermined DC / DC converter side voltage Vdk1 for controlling the bidirectional inverter 17 that monitors the overvoltage between the bidirectional inverter 17 and the DC / DC converter 51 can be easily set. .

  Similarly, the second predetermined DC / DC converter side voltage Vdk2 can be freely set in a range lower than the first predetermined DC / DC converter side voltage Vdk1, so that the bidirectional inverter 17 and DC / For controlling the DC / DC converter 51, which monitors overvoltage between the bidirectional inverter 17 and the DC / DC converter 51 in accordance with the specification even if at least one of the DC converter 51 has a different specification. The second predetermined DC / DC converter side voltage Vdk2 can be easily set.

  These five parameters (predetermined system power supply side voltage Vik, predetermined current Ik, predetermined power storage unit voltage Vbk, first predetermined DC / DC converter side voltage Vdk1, second predetermined DC / DC converter side voltage Vdk2) are variable signals K. A plurality of them may be included at the same time. In this case, a plurality of parameters can be set collectively.

  Here, if at least one of the above five parameters is changed while the power supply device 11 is in use, an overcurrent may flow or the operation of the bidirectional inverter 17 or the DC / DC converter 51 may become unstable depending on the set value. Therefore, it is desirable to change the above parameters by the variable signal K before the power supply device 11 is activated.

  Operations other than the above are the same as those in the fourth embodiment.

  In the sixth embodiment, the configuration further including the external device 41 and the external device terminal 43 in the configuration of the fourth embodiment has been described. However, the configuration of the fourth embodiment is the same as that of the fifth embodiment. The configuration of the fifth embodiment may further include an external device 41 and an external device terminal 43.

  In this case, the predetermined current Ik is a set value for the DC / DC converter 51 among the five parameters. Therefore, the DC / DC converter 51 is controlled so that the current I becomes the set default current Ik if the variable signal K includes the default current Ik. As a result, the predetermined current Ik for monitoring the overcurrent can be easily set according to the specifications of the DC / DC converter 51 and the power storage unit 19.

  With the above configuration and operation, according to the variable signal K of the external device 41, the predetermined system power supply side voltage Vik, the default current Ik, the default power storage unit voltage Vbk, the first default DC / DC converter side voltage Vdk1, or the second default Since at least one of the DC / DC converter side voltages Vdk2 can be freely set, when using the power supply device 11 in an area where the standard of the system power supply 13 is different, it is very easy to respond to the power situation in the area. Thus, the power supply device 11 that can set the predetermined system power supply side voltage Vik is obtained. Also, the overcurrent and overvoltage monitoring set values can be easily changed according to the specifications of the power supply device 11, and high reliability can be obtained.

  In the sixth embodiment, as described in the third embodiment, another control of the power supply device 11 (for example, manual on / off control of the switch 15 or the like) by the variable signal K and information other than the above five parameters. ) May be performed.

  Further, also in the sixth embodiment, the variable signal K may be set to bidirectional communication as in the third embodiment. In this case, the external device 41 can monitor the abnormality of the power supply device 11 by obtaining, for example, the current and voltage characteristics of each part of the power supply device 11.

  In the first to sixth embodiments, the power supply device 11 has been described as one for supplying power from the power storage unit 19 at the time of a power failure of the system power supply 13 (uninterruptible power supply device or emergency backup power supply device). The power supply device 11 may be applied to, for example, an electric vehicle or a plug-in hybrid vehicle. In this case, when a power failure occurs during charging of the battery of the electric vehicle or the plug-in hybrid vehicle, the power from the battery can be immediately supplied to the load in the home.

  The power supply device according to the present invention is particularly useful as an uninterruptible power supply, an emergency backup power supply, and the like because it can immediately supply power to the load even if a power failure occurs while charging the power storage unit.

DESCRIPTION OF SYMBOLS 11 Power supply device 13 System power supply 15 Switch 17 Bidirectional inverter 19 Power storage part 21 Input / output voltage detection part 22 Current detection part 23 Control part 37 Power storage part voltage detection part 41 External equipment 43 External equipment terminal 51 DC / DC converter 53 System power supply side Voltage detector 55 DC / DC converter side voltage detector

Claims (7)

A bidirectional inverter electrically connected to the system power supply via a switch;
A power storage unit electrically connected to the bidirectional inverter;
An input / output voltage detection unit electrically connected to the system power supply side of the bidirectional inverter;
A current detection unit that detects a current (I) flowing through the power storage unit;
A control unit electrically connected to the switch, bidirectional inverter, input / output voltage detection unit, and current detection unit;
When the current (I) reaches a predetermined current (Ik), the control unit performs control to maintain the current (I).
If the current (I) does not reach the predetermined current (Ik), the input / output voltage (Va) detected by the input / output voltage detector is a predetermined voltage (Vad) lower than the specified lower limit voltage (Vad) of the system power supply. Vak)
While performing for each bidirectional inverter,
A power supply apparatus that controls to turn off the switch when discharging the power storage unit and to turn on the switch at other times. An external device terminal for electrically connecting the control unit and the external device;
The control unit sets at least one of the predetermined voltage (Vak) or the predetermined current (Ik) in accordance with a variable signal (K) from the external device input from the external device terminal. The power supply device according to claim 1. A power storage unit voltage detection unit electrically connected to the control unit;
When the power storage unit voltage (Vb) detected by the power storage unit voltage detection unit reaches a predetermined power storage unit voltage (Vbk), the control unit gives first priority to control for maintaining the power storage unit voltage (Vb). The power supply device according to claim 1. An external device terminal for electrically connecting the control unit and the external device;
The control unit is configured to output the predetermined voltage (Vak), the predetermined current (Ik), or the predetermined power storage unit voltage (Vbk) according to a variable signal (K) from the external device input from the external device terminal. The power supply device according to claim 3, wherein at least one of the following is set. A bidirectional inverter electrically connected to the system power supply via a switch;
A DC / DC converter electrically connected to the bidirectional inverter;
A power storage unit electrically connected to the DC / DC converter;
A system power supply side voltage detection unit that is electrically connected to the system power supply side of the bidirectional inverter and detects a system power supply side voltage (Vi);
A DC / DC converter side voltage detection unit that is electrically connected to the DC / DC converter side of the bidirectional inverter and detects a DC / DC converter side voltage (Vd);
A power storage unit voltage detection unit that is electrically connected to the power storage unit and detects a power storage unit voltage (Vb);
A current detection unit that detects a current (I) flowing through the power storage unit;
A control unit electrically connected to the switch, bidirectional inverter, DC / DC converter, system power supply side voltage detection unit, DC / DC converter side voltage detection unit, power storage unit voltage detection unit, and current detection unit; Prepared,
In the operation of the bidirectional inverter,
When the DC / DC converter side voltage (Vd) reaches the first predetermined DC / DC converter side voltage (Vdk1), the control unit gives first priority to control for maintaining the DC / DC converter side voltage (Vd). Done in
If the DC / DC converter side voltage (Vd) does not reach the first predetermined DC / DC converter side voltage (Vdk1) and the current (I) reaches the predetermined current (Ik), the current (I ) Is maintained with second priority,
If the DC / DC converter side voltage (Vd) does not reach the first predetermined DC / DC converter side voltage (Vdk1) and the current (I) does not reach the predetermined current (Ik), the system Control is performed with the third priority so that the power supply side voltage (Vi) becomes a predetermined system power supply side voltage (Vik) lower than the specified lower limit voltage (Vad) of the system power supply,
In the operation of the DC / DC converter,
When the power storage unit voltage (Vb) reaches the predetermined power storage unit voltage (Vbk), the control unit performs control to maintain the power storage unit voltage (Vb) with first priority,
If the power storage unit voltage (Vb) does not reach the predetermined power storage unit voltage (Vbk), the DC / DC converter side voltage (Vd) is lower than the first predetermined DC / DC converter side voltage (Vdk1). 2 Control is performed with the second priority, so that the predetermined DC / DC converter side voltage (Vdk2) is obtained.
The control unit performs the operation of the bidirectional inverter and the operation of the DC / DC converter in parallel, and turns off the switch when the power storage unit is discharged, and turns on the switch at other times. Power supply device that controls to A bidirectional inverter electrically connected to the system power supply via a switch;
A DC / DC converter electrically connected to the bidirectional inverter;
A power storage unit electrically connected to the DC / DC converter;
A system power supply side voltage detection unit that is electrically connected to the system power supply side of the bidirectional inverter and detects a system power supply side voltage (Vi);
A DC / DC converter side voltage detection unit that is electrically connected to the DC / DC converter side of the bidirectional inverter and detects a DC / DC converter side voltage (Vd);
A power storage unit voltage detection unit that is electrically connected to the power storage unit and detects a power storage unit voltage (Vb);
A current detection unit that detects a current (I) flowing through the power storage unit;
A control unit electrically connected to the switch, bidirectional inverter, DC / DC converter, system power supply side voltage detection unit, DC / DC converter side voltage detection unit, power storage unit voltage detection unit, and current detection unit; Prepared,
In the operation of the bidirectional inverter,
When the DC / DC converter side voltage (Vd) reaches the first predetermined DC / DC converter side voltage (Vdk1), the control unit gives first priority to control for maintaining the DC / DC converter side voltage (Vd). Done in
If the DC / DC converter side voltage (Vd) does not reach the first predetermined DC / DC converter side voltage (Vdk1), the system power supply side voltage (Vi) is the specified lower limit voltage (Vad) of the system power supply. In addition to performing control such that the predetermined system power supply side voltage (Vik) is lower than the second priority,
In the operation of the DC / DC converter,
When the power storage unit voltage (Vb) reaches the predetermined power storage unit voltage (Vbk), the control unit performs control to maintain the power storage unit voltage (Vb) with first priority,
If the power storage unit voltage (Vb) does not reach the predetermined power storage unit voltage (Vbk) and the current (I) reaches the predetermined current (Ik), the second control is performed to maintain the current (I). With priority,
If the power storage unit voltage (Vb) does not reach the predetermined power storage unit voltage (Vbk) and the current (I) does not reach the predetermined current (Ik), the DC / DC converter side voltage (Vd ) Is controlled with the third priority so that the second predetermined DC / DC converter side voltage (Vdk2) is lower than the first predetermined DC / DC converter side voltage (Vdk1).
The control unit performs the operation of the bidirectional inverter and the operation of the DC / DC converter in parallel, and turns off the switch when the power storage unit is discharged, and turns on the switch at other times. Power supply device that controls to An external device terminal for electrically connecting the control unit and the external device;
In accordance with a variable signal (K) from the external device input from the external device terminal, the control unit is configured to output the predetermined system power supply side voltage (Vik), the predetermined current (Ik), and the predetermined power storage unit voltage ( 7. The device according to claim 5, wherein at least one of Vbk), the first predetermined DC / DC converter side voltage (Vdk1), or the second predetermined DC / DC converter side voltage (Vdk2) is set. Power supply.

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