JP4527560B2 - DC power supply method and apparatus using charging circuit - Google Patents

Description

  The present invention relates to a method and an apparatus capable of driving in a short time even a large power load that requires a large current when supplying DC power to the load via a charging circuit including a capacitor that also serves as standby power. It is. In particular, a solar cell having a relatively weak output time zone such as cloudy or rainy weather and a non-output time zone such as nighttime is used as received power, and intermittently requires high power, such as a wireless device. The present invention relates to a direct-current power supply method and apparatus that require a capacitor having a large capacitance and a quick charging function for various conditions.

  A DC power supply device using a conventional charging circuit is connected to a rechargeable battery, and the charging is completed in consideration of a state where commercial power does not reach such as a power failure or a moving object. Alternatively, the stored voltage is supplied to the load while charging.

  Recently, a small-sized, large-capacitance, special charging circuit or an electric double layer capacitor (capacitor) that does not require restrictions during discharging has been used for such an auxiliary power storage device. It is also practically used in applications that use solar cells as received power in wireless communication stations, etc.

  As a DC power supply apparatus using such a charging circuit, there is, for example, JP-A-11-55870 (Patent Document 1) as a charging apparatus using a solar cell. This charging device is practically sufficient for the purpose of operating at least a small power load normally using at least two electric double layer capacitors.

  This will be described with reference to FIG.

As illustrated, the charging device includes a plurality of electric double layer capacitors that are charged from one solar cell 1 as capacitors C _SM 3 and C _LG 4. Since the capacitor C _SM 3 has a small capacitance, the charging time is short, and since the capacitor C _LG 4 has a large capacitance, the charging time is long. The capacitor C _SM 3 supplies power to a basic power control circuit 111 mainly composed of an IC (integrated circuit) that operates with small power and a control circuit 110 with a small power load including a voltage detection unit 112 such as a sensor. One capacitor C _LG 4 supplies electric power to a load driving circuit 121 that drives a load circuit 122 serving as a high power load such as a rotating mechanism or a transmission circuit.

The capacitors C _SM 3 and C _LG 4 are simultaneously charged from the solar cell 1. However, capacitor C _{SM 3,} since the capacitance is small charging time is short, can be fully charged in a relatively short period of time. Since the voltage detection unit 112 detects the full charge state and notifies the basic control circuit 111, the basic control circuit 111 enables the control operation of the load drive circuit 121 of the drive circuit 120. Since the capacitor C _SM 3 has a small load even if it has a small capacitance, the low-power load can be normally operated over a long period of time even without sufficient charging due to cloudy weather or the like.

The basic control circuit 111 monitors the state of charge of the battery C _LG 4. Therefore, when the battery is not sufficiently charged, the load circuit 122 is prevented from being stopped, for example, by controlling the load driving circuit 121 according to the detection result to reduce the power consumption in the large power load.

  However, in order to operate a high power load, the battery must have a large capacitance commensurate with the high power load. Such a large-capacity capacitor requires a long time of charging in order to secure a predetermined output voltage. Therefore, in the device disclosed in Patent Document 1, even if a small power load operates normally in a short time, a large-capacity capacitor is insufficiently charged, so that the large power load cannot be driven in a short time. .

Japanese Patent Laid-Open No. 11-55870

  The problem to be solved is that in a DC power supply device that requires both a large-capacity capacitor that can handle a large power load and a quick charging function, in the case of low received power such as a solar cell. Even if the storage battery is used for a low power load and a high power load, charging of the low power load can be completed, but the high power load cannot be driven in a short time.

  The present invention includes at least two charging circuits including a battery so that a large power load can be driven in a short time. Then, the battery included in the charging circuit is charged, and the charged charging circuit is sequentially connected to the load. Thus, the main feature is that the DC output is continuously supplied to the load.

  However, it is sufficient if the received power is as strong as commercial power. However, in the case of a weak received power such as a solar battery, it is further preferable to sequentially select the charging circuits one by one when starting charging. It is a feature.

  This first charged capacitor has a capacitance sufficient to maintain the operation of the load even when there is a voltage drop due to discharge until the next charging circuit is fully charged when this charging circuit is connected to the load. is doing. In this way, it is possible to obtain an appropriate configuration in which charging of the plurality of charging circuits is sequentially completed and the output can be connected to the load. As a result, DC power is continuously supplied to the load, and the operation of the load does not stop.

  In other words, with this configuration, capacitors with low capacitance can be charged sequentially and continuously at the charging start stage, so the charging time of the capacitors can be shortened in the initial stage and power can be supplied to the load in a short time. It becomes. If a high-power load is connected at this point, a voltage drop will occur, but if the supply voltage can be maintained within the charging time when the next-order capacitors are fully charged, switching the capacitors with smaller capacitances in sequence will increase the voltage. It enables continuous power supply to the current load. Therefore, for example, a configuration in which a small number of capacitors having the same capacitance are circulated and charged / discharged is also possible. However, in this case, a receiving power source such as a solar battery cannot sufficiently store electricity, and there is a risk of stopping operation in cloudy or rainy weather.

  Therefore, each of the charging circuits includes a capacitor having a different capacitance, and the charging circuit is sequentially charged from the smallest capacitance to the larger one at the start of charging. It is desirable to select In other words, since it can be finally stored in a capacitor having a large capacitance, a stable power supply operation can be performed. Furthermore, after charging up to the capacitor with the largest capacitance, the remaining charging circuit was connected to an insufficiently charged capacitor to fully charge, and the charged capacitor was connected to the load. All the capacitance can cover the power consumption of the load. The connection at the time of charging and the connection after charging can be performed one by one or collectively.

Therefore, the DC power supply device according to the present invention includes at least two charging circuits each having a capacitor, capacitor selecting means for selecting at least one of the charging circuits to be charged, and DC power connected to a load. A power supply selecting means for selecting at least one from the charging circuit to be supplied, and charging the related charging circuit by controlling the capacitor selecting means, and when the completion of charging is detected with a predetermined detection voltage, the power supply In the DC power supply apparatus comprising: a control unit that selects a charging circuit that has been charged by controlling the selection unit, sequentially connects the charging circuit to a load, and supplies DC power at a predetermined adjustment voltage. , Corresponding to each of the capacitors, when the respective storage voltage is input and when the corresponding switching signal is received, An output adjusting circuit for outputting a supply voltage to the load at a predetermined adjustment voltage, detected by the monitoring voltage is set between the detection voltage and the regulated voltage a voltage that allows the complete driving of the predetermined load by the charge start And a gate circuit that drives the output adjustment circuit to output the supply voltage when receiving the monitoring voltage detection notification from the voltage monitoring circuit.

  The direct-current power supply method and apparatus according to the present invention include a plurality of capacitors each having a small electrostatic capacity as a plurality of capacitors having a small electrostatic capacity as a reserve power for received power. Since it can be charged and the voltage can be continuously supplied to the load, even a small amount of received power like a solar battery can be charged to a plurality of small capacitance capacitors in a short time and continued to the load when charging is completed. Thus, there is an advantage that the driving can be started in a short time even for a large power load and the functional operation of the apparatus can be maintained. This is particularly effective in an apparatus in which a large power load is driven intermittently.

  For the purpose of being able to drive in a short time against a large power load and a weakly received power such as a solar cell in a DC power supply device having a charging circuit, the battery has at least two charging circuits equipped with a capacitor, This was realized by sequentially selecting the charging circuits one by one, sequentially charging the capacitors included in the charging circuit, sequentially connecting the charged charging circuits to the load, and continuously supplying DC power.

  In the present invention, a plurality of capacitors and their charging circuits are required. Therefore, the capacitor has a large capacitance per volume, and a special charging circuit and an electric double layer capacitor that does not require restrictions during discharging ( Capacitor). Further, with reference to the drawings, the following embodiments are directed to a DC power supply device using a solar cell having input power with unstable conditions such as cloudy sky and unstable charging environment and nighttime power reception stoppage. Will be explained.

  A first embodiment of the present invention will be described with reference to FIG.

  FIG. 1 is an explanatory diagram showing functional blocks of a first embodiment of a DC power supply apparatus having a charging circuit according to the present invention.

A DC power supply which is illustrated, the solar cell 1, the load 2, an electric double layer capacitor _C SM 3 using a _{capacitor, C LG} 4, the capacitor selection unit (hereinafter, abbreviated as SWC) 5, and a power supply selection means (Hereinafter abbreviated as SWS) 6 is provided.

Solar cell 1 is shown as receiving power, DC power supply apparatus supplies a direct-current power by the supply voltage V _SP to the load 2 by the power generation of the solar cell 1. One electrode of the solar cell 1 is connected to the charging circuit via a backflow preventing diode and a current limiting resistor, and the other electrode is grounded.

Load 2 has a voltage detector 11, switching control unit 12, CPU 13, and high-power load driver 14, operates receiving supply of the supply voltage _{V SP} via the charging circuit.

One capacitor C _SM (hereinafter abbreviated as C _SM ) 3 is an electric double layer capacitor having a small electrostatic capacity and has a short charging time. However, although this C _SM 3 has a small capacitance, it is connected to the load 2 after completion of charging, and even if there is a voltage drop due to discharging, the other capacitor C _LG (hereinafter abbreviated as C _LG ) 4 is charged. Has enough capacitance to maintain the operation of the load until it is completed. The _{C SM} 3, one was connected to SMC5, grounding the other.

The other capacitor C _LG (hereinafter abbreviated as C _LG ) 4 is an electric double layer capacitor having a large capacitance and a long charging time. Therefore, the C _LG 4 is provided to the high power load driving unit 14 that drives a high power load such as a rotating mechanism or a transmission circuit even when the solar cell 1 has a power generation shortage due to rain or cloudy weather and a no power generation state at night. Electric power can be supplied to maintain the load for a long time. The _{C LG} 4 also connected one to the SMC5, grounding the other.

The SWC 5 connects the DC power received from the solar cell 1 to the C _SM 3 for charging in the initial OFF state, and enters the ON state by accepting the switching signal SWc and connects to the C _LG 3 from the C _SM 3 for charging. Switch. SWS6 _{is, C} SM _3, C _LG 4 draws each SWC5 connection side, the initial of the voltage _{V SM} connected to _{C SM} 3 is in the off state, also turned on by the reception of the switching signal SWs _{C SM} The connection is switched from 3 to C _LG 4 and the voltage V _LG is switched to adjust the voltage and supplied to the load 2 as a stable supply voltage V _SP .

The voltage detection unit 11 pulls in the SWC5 connection side of each of C _SM 3 and C _LG 4, monitors each of the voltages V _SM and V _LG to detect the full charge voltage V _DT , and notifies the switching control unit 12 of the completion of charging. To do. Switching control unit 12 receives a notification of the charge completion from the voltage detection unit 11, a switching signal SWc to SWC5 the case of the voltage _{V SM,} when the voltage _{V LG} is to SWS6 a switching signal SWs, sent respectively. The CPU 13 is a normal control circuit constituted by an IC, and is a small power load together with the voltage detection unit 11 and the switching control unit 12. The high power load driving unit 14 is a high power load that drives wireless transmission, a rotation mechanism, and the like.

  Next, the functional operation will be described with reference to FIG.

Here, it is assumed that C _SM 3 has a charging time T _S and C _LG 4 has a charging time T _L. The charging time T _S is shorter than the charging time T _L of C _LG 4 having a large capacitance based on the small capacitance of C _SM 3. The voltage detection unit 11 uses _VDT as a detection voltage. In order to verify the longest drive start time, each of C _SM 3 and C _LG 4 is in an initial state and is not charged. In the conventional apparatus, when applied to a large power load, the time until the start of driving of the large power load is the charging time _TL of C _LG 4.

As shown in FIG. 1, the electric power generated by the solar cell 1 is connected to the _{C SM} 3 via SMC5, and further connected as the supply voltage _{V SP} from SMC5 to the load 2 via the SMS6 . Further, it is assumed that the voltage required for the load 2 to maintain operation is V _NG or higher.

First, the power generated by the solar cell 1 is supplied to the C _SM 3 via the SMC 5 with the DC power supply device turned “ON”. The voltage V _SM of C _SM 3 reaches the voltage V _DT with a short charging time T _S. At this point, the load 2 is all possible functions operate, SWS6 can start supplying a voltage _{V SM} as the supply voltage _{V SP} to the load. That is, it is possible to start driving the load 2 with a short charging time T _S of C _SM 3.

On the other hand, when the load 2 reaches the detection voltage V _DT , the voltage detection unit 11 notifies the detection of the detection voltage V _DT to the switching control unit 12 and the CPU 13. By this notification, the switching control unit 12 outputs the switching signal SWc to turn on the SWC 5, so that the electric power generated by the solar cell 1 is supplied to C _LG 4. The voltage V _LG of C _LG 4 reaches the detection voltage V _DT with a long charging time _TL to complete the charging, and the voltage detection unit 11 detects this and notifies the switching control unit 12 and the CPU 13 of it. At this time, the voltage V _LG of C _LG 4 is supplied to the load 2 as the supply voltage V _SP .

The voltage V _SM of C _SM 3 hardly decreases at the time T _L in the case of a low power load. However, when the high power load driving unit 14 is driven at the start of the time _TL , the voltage drop is unavoidable as illustrated by the broken line. For this reason, the small capacitance of C _SM 3 is set so as not to cause a voltage drop until the voltage becomes lower than the above voltage V _NG within the time _{TL in} the case of the maximum large power load until it becomes inoperable. ing. However, in the case where _CSM 3 has a small electrostatic capacity due to the speed of driving, the electric double layer capacitor may be added as a charging circuit.

  Since such a circuit configuration is adopted, the capacitor having the capacitance corresponding to the maximum power consumption is not charged from the beginning, the capacitor is divided, and the capacitance of the capacitor to be charged first is required. It can be set to a value commensurate with the operation start time. Therefore, the operation of the apparatus can be started easily in a short time.

Further, although not shown in FIG. 2, it can be SWC5 is subjected to switching signal SWs, connected to the C _{SM 3} again solar cell 1 in the disconnected charged sequentially connected in parallel. In this case, since the electrostatic capacity of the capacitor with respect to the load 2 is summed, long-term normal operation can be ensured even if the supply voltage _VSP is stabilized and the received power is cut off due to the decrease in the output of the solar cell 1. . In other words, when considering a low-power and high-power load such as a solar battery, it is equipped with a capacitor with a capacitance that can be driven and maintained for a desired long time even when the received power is cut off. It is possible to start operation quickly by dividing.

  In the above description, the charging circuit for each of the two electric double layer capacitors has been described with reference to the drawings. However, as described above, three or more charging circuits may be provided.

  A second embodiment of the present invention will be described with reference to FIG.

  The second embodiment of FIG. 3 shows a system that operates an unmanned radio station apparatus as a load 20 using the power generated by the solar cell 1. A radio station transmits and receives data using radio waves, but a transmitter needs relatively large power to transmit data reliably to a distance. Since it is the same structure as FIG. 1 of the said Example 1 except the load 20, the same number is attached | subjected to the same component and the description is abbreviate | omitted.

  The load 20 includes a CPU 21, a ROM (read only memory) 22, a temperature sensor 23, and a wireless LSI (large scale integrated circuit) 24.

  The CPU 21 reads temperature information from the temperature sensor 23 by a program stored in advance in the ROM 22, controls the wireless LSI 24, and controls SWC5 and SWS6. For example, the CPU 21 performs control such that the operating power is reduced when the temperature around the apparatus deviates from an appropriate temperature by the temperature sensor 23. That is, the ROM 22 stores a program provided to the CPU 21 in advance. The temperature sensor 23 detects the ambient temperature of the apparatus.

In Example 2, the capacitance of the electric double layer capacitor by the capacitor C _SM 3 is 0.5F, and the capacitance of the electric double layer capacitor by the capacitor C _LG 4 is 1F.

  The wireless LSI 24 consumes 50 mA of current when wirelessly transmitting and receiving data. When no wireless data transmission / reception is performed, a current of 1 mA is consumed. The wireless data transmission / reception is periodically performed for 15 seconds per minute, and when there is no power generation by the solar cell 1, wireless data transmission / reception is not performed. In such an environment, the wireless LSI 24 needs to continue operation for at least 30 minutes with the power stored in the electric double layer capacitor.

From the above conditions, 1.2F is set as the electrostatic capacity of the electric double layer capacitor necessary for this wireless device. Therefore, as described above, when both of the capacitors C _SM 3 and C _LG 4 are fully charged, although not shown, since both can supply a DC voltage to the load 20, The sum should be 1.2F.

Further, in order to perform one-time transmission / reception of data by radio, the electric double layer capacitor C _SM 3 having a small capacitance that is charged first needs to be charged with a voltage of about 4 V or more. Therefore, it is possible to set the operation starting voltage capable V _OP that is required when the load 20 described in FIG. 2 cover the first high-power load 4V.

  A third embodiment of the present invention will be described with reference to FIG.

  Example 3 of FIG. 4 shows one form of the implementation circuit of SWC (capacitor selection means) in FIG. 3 as SWC30. Since the configuration other than the SWC 30 is the same as that in FIG. 3 of the second embodiment, the same reference numerals are given to the same components and the description thereof is omitted.

  The SWC 30 includes a switch (hereinafter abbreviated as SWc) 31, a solenoid 32, a solenoid control transistor (hereinafter abbreviated as TR) 33, and a pull-down resistor 34.

The SWc 31 receives power from the solar cell 1 via a backflow prevention diode and a current limiting resistor, and supplies the received power to the SWS 6 together with C _SM 3 having a small capacitance in the initial state. SWc31 is switched from C _SM 3 to C _LG 4 having a large capacitance when receiving a switching signal SWc from CPU 21. Solenoid 32 and TR33 are connected in series, and one is adjusted voltage V Connected to _RG 3.3V, the other is grounded. The base of TR33 is grounded via a pull-down resistor 34, and is connected to the CPU 21 and receives a switching signal SWc.

With such a configuration, the CPU 21 sends the switching signal SWc to the TR 33 and causes the current to flow through the solenoid 32, thereby turning on the SWc 31. At the start power generation by the solar cell 1 in the initial state, the voltage V _RG applied to the solenoid 32 is zero volts. When no current flows through the solenoid 32, the SWc 31 is in an “off” state. If SWc31 is "off" state, C _{SM 3} small capacitance is charged is connected to the solar cell 1. Even if the voltage _VRG 3.3V is generated as the power voltage, when the control terminal of the CPU 21 is not set to the switching signal SWc output, the control terminal of the CPU 21 is high impedance, and the base of the TR 33 is grounded by the pull-down resistor 34. Therefore, TR33 is in the “off” state.

When the voltage _VRG 3.3V is generated in the power line and the control terminal of the CPU 21 is set as an output terminal and outputs a high level, the TR 33 is driven, a current flows through the solenoid 32, and the SWc 31 is turned on. When the SWc 31 is in the “on” state, the electric power from the solar cell 1 is switched from the charging to the C _SM 3 having a small capacitance until then to charging the C _LG 4 having a large capacitance.

  A fourth embodiment of the present invention will be described with reference to FIG.

  Example 4 of FIG. 5 is a form different from Example 3 of the implementation circuit of the SWC (capacitor selection means) in FIG. Since the configuration other than the SWC 50 is the same as that of FIG. 3 of the second embodiment, the same reference numerals are given to the same components and the description thereof is omitted.

  The SWC 50 includes two diodes 51 and 52, a photocoupler 53, a photocoupler control transistor (hereinafter referred to as TR) 54, and a pull-down resistor 55.

The diode 51 receives power from the solar cell 1 via a current limiting resistor for backflow prevention, and always supplies the received power to the _CSM 3 having a small capacitance. The diode 52 receives power from the solar cell 1 through a current limiting resistor for backflow prevention, and switches the received power to C _LG 4 having a large capacitance by a switching transistor of the photocoupler 53 (hereinafter abbreviated as SWc). To be supplied via).

The photocoupler 53 is composed of the SWc and a photodiode (hereinafter abbreviated as PD). The PD and TR54 are connected in series, and one is connected to the adjustment voltage _VRG 3.3V and the other is grounded. Yes. The base of TR54 is grounded via a pull-down resistor 55, and is connected to the CPU 21 and receives a switching signal SWc.

With such a configuration, the CPU 21 sends a signal to the TR 54 and causes a current to flow through the PD of the photocoupler 53, thereby turning SWc on. At the start power generation by the solar cell 1 in the initial state, the adjustment voltage V _RG applied to the PD is zero volts. When no current flows through the PD, SWc is in the “off” state.

Therefore, C _SM 3 having a small electrostatic capacity is charged whenever there is power generation by solar cell 1. Photocoupler 53 connected to the _{C LG} 4 large capacitance, when the adjustment voltage _{V RG} 3.3V occurs and the control terminal of the CPU21 has outputs a high level is set to the switching signal SWc output, the TR54 The “on” state is entered, a current flows through the PD in the photocoupler 53, and the SWc of the photocoupler 53 is turned on. Power from the solar cell 1 the photo-coupler 53 becomes "on" state, with the charge to the C _{SM 3} small capacitance so far, also starts to charge to the C _{LG 4} large capacitance.

  Therefore, in the fourth embodiment, the charging circuit is formed and the charging is always completed even when the capacitor having the small electrostatic capacity charged first is sequentially switched to the next large electrostatic capacity. Therefore, when the capacitor supplied to the load drops below a predetermined voltage, the connection is switched in the reverse order to the charging order, and the CPU controls to use the capacitance using the capacitor that has been charged up to that point. be able to.

  Next, the SWS (power supply selection means) 60 in the fifth embodiment will be described with reference to FIG.

  FIG. 6 shows an embodiment of a circuit related to SWS 6 in FIG. 3 as SWS 60. Since the configuration other than the SWS 60 is the same as that in FIG. 3 of the second embodiment, the same reference numerals are given to the same components and the description thereof is omitted.

The SWS 60 includes output adjustment circuits 61 and 62, a voltage monitoring circuit 63, a gate circuit 64, pull-down resistors 65 and 66, and diodes 67 and 68. The output adjustment circuits 61 and 62 are diodes 67 and 68 connected in series, connected to the supply voltage output terminal, and output the adjusted constant voltage _VRG 3.3V.

One input of the output adjustment circuit 61 is a voltage V _SM by the plus terminal side of C _SM 3 having a small capacitance, and the other input is an enable signal output from the gate circuit 64. By this enable signal, the output adjustment circuit 61 outputs the adjusted positive constant voltage V _RG 3.3V. One input of the output adjustment circuit 62 is a voltage V _LG by the positive terminal side of C _LG 4 having a large capacitance, and the other input is a switching signal SW _S2 output from the CPU 21. In response to the switching signal SW _S2 , the output adjustment circuit 62 outputs the adjusted positive constant voltage _VRG 3.3V.

The voltage V _SM on the positive terminal side of C _SM 3 is connected to one input terminal of the CPU 21, the voltage monitoring circuit 63, and the output adjustment circuit 61. The voltage monitoring circuit 63 monitors the arrival of the charge detection voltage V _DT 4V in order to charge the C _SM 3 so that the apparatus can be operated. The gate circuit 64 connects the output of the voltage monitoring circuit 63 to one input terminal, and connects the pull-down resistor 65 grounded at the other end to the other input terminal to invert the switching signal SW _S1 output from the CPU 21. , Respectively, take the logical product and output an enable signal. Accordingly, the enable signal when the voltage V _SM reaches 4V output from the gate circuit 64 to the other input terminal of the output adjusting circuit 61.

The voltage V _LG on the positive terminal side of C _LG 4 is connected to one input terminal of the CPU 21 and the output adjustment circuit 62. To the other input terminal of the output adjusting circuit 62, the switching signal SW _S2 output from the CPU21 is connected, it is connected to the pull-down resistor 66 which is grounded at the other end.

The switching signal SW _S1 and the switching signal SW _S2 described above are independently controlled by the CPU 21, but may be simultaneous switching signals SWs as in the above-described embodiment.

  Next, Example 6 will be described with reference to FIGS.

  FIG. 7 is an explanatory diagram illustrating functional blocks of a sixth embodiment of the DC power supply apparatus having a charging circuit different from the first and second embodiments illustrated in FIGS. The sixth embodiment has a configuration in which the SWC 5 and SWS 6 in FIG. 3 showing the second embodiment are replaced with the SWC 50 in FIG. 5 shown in the fourth embodiment and the SWS 60 in FIG. 6 shown in the fifth embodiment. Yes. Since the SWC 50 and SWS 60 shown in FIG. 7 show the respective blocks in a simplified manner, the description of the corresponding embodiment can be referred to for details. Other than that, the configuration is the same as that of the second embodiment shown in FIG. Therefore, the same reference numerals are given to the same components of the respective components, and the description thereof is omitted.

Further, FIG. 8 shows that in FIG. 7, the solar cell 1 starts generating power in the initial state in which no power is generated from the solar cell 1 and neither of the capacitors C _SM 3 and C _LG 4 is charged by the two electric double layer capacitors. It is a time chart which shows one form of the voltage condition in the main location in the state where the load is not applied on a time axis. Here, a voltage V _SM of C _SM 3 having a small capacitance, a voltage V _LG of C _LG 4 having a large capacitance, and an adjustment voltage V _RG supplied to the load 20 are shown.

The reference voltages are the detection voltage V _DT at the CPU 21 with respect to the full charge voltage, the monitoring voltage V _OP 4V at the SWS 60, and the adjustment voltage V _RG 3.3V at the adjustment output circuits 61 and 62. The time T _S is a charging time from when the power is turned “on” by the power generation of the solar cell 1 until C _SM 3 is charged to reach the detection voltage V _DT and the switching signal SWc is generated. The time _TL is a charging time from when the switching signal SWc is generated until C _LG 4 is charged and reaches the detection voltage V _DT until the CPU 21 generates the switching signal SW _S2 or SWs.

From the time it reaches the power supply can be monitored voltage V _{OP 4V} from the charge start to the load 20, the voltage V _SM of C _{SM 3} during charging is started and supplied to output adjusted to the load 20. In addition, after the switching signal SW _S2 is generated, the voltage V _LG of the C _LG 4 that has been charged is adjusted and supplied to the load 20.

  Next, main operations in FIG. 7 will be described with reference to FIGS. 7, 8, and FIGS. 3, 5, and 6 together.

The initial state is a state where there is no power generation from the solar cell 1 and neither of the electric capacitors C _SM 3 and C _LG 4 of the two electric double layer capacitors is charged.

First, the solar cell 1 starts power generation when any light hits the connected solar cell 1. Since the SWC 50 is in the “off” state, the electric power generated by the solar cell 1 is charged to the small capacitance C _SM 3. When the voltage V _{SM of the} small capacitance C _SM 3 reaches the operable voltage V _OP 4V, the output of the voltage monitoring circuit 63 becomes high level, so that one input terminal of the gate circuit 64 becomes high level. . Since the other input terminal of the gate circuit 64 is not yet supplied with power to the CPU 21, a low level is input by a pull-down resistor. As a result, the output of the gate circuit 64 becomes high level, and the enable signal is supplied to the output adjustment circuit 61. Therefore, the output adjustment circuit 61 outputs and supplies the adjustment voltage _VRG 3.3V as a supply voltage to each integrated circuit in the apparatus including the load 20.

CPU21 that received adjustment voltage V _RG 3.3V immediately starts a read operation of a program from the ROM 22, and controls the radio LSI 24, the data whether there is another wireless device to be communicated in the vicinity of the wireless device Confirm by sending and receiving. CPU21 will transmit the data of a temperature sensor for every minute, if communication with the other wireless apparatus which should communicate is established. Incidentally, it takes 15 seconds to transmit data once.

The CPU 21 performs regular wireless data communication and monitors the voltage V _SM of the small capacitance C _SM 3 via an analog terminal. When the voltage V _{SM of the} small capacitance C _SM 3 becomes equal to or higher than the predetermined voltage V _DT , the CPU 21 outputs a high-level switching signal SWc to the control terminal to the SMC 50 and turns on the switch SWc by the photocoupler. In this state, the electric power generated by the solar cell 1 is switched to the charging of the _CLG 4 having a large electrostatic capacity.

Thereafter, the CPU 21 performs periodic wireless data communication and monitors the voltage V _LG of the large capacitance C _LG 4 via an analog terminal. When the voltage V _{LG of the} large capacitance C _LG 4 becomes equal to or higher than the predetermined voltage V _DT , the CPU 21 outputs a high level to the switching signal SW _S2 which is an enable control signal, and enables the output adjustment circuit 62. The output adjustment circuit 62 outputs the adjustment voltage _VRG 3.3V. At the same time, the CPU 21 disables the output adjustment circuit 61 because the switching signal SW _S1 that is an enable control signal is output to the gate circuit 64 at a high level. As a result, the power supply to each circuit is switched from C _SM 3 having a small capacitance to C _LG 4 having a large capacitance.

Then, CPU 21 has a _C voltage _LG 4 _{V LG} large capacitance and voltage _{V SM} of _{C SM} 3 the static capacitance, and monitored via the analog terminals in accordance with a predetermined algorithm, SWC50 and SWS60 And the power supply to the wireless device using the electric double layer capacitor device of the present invention is controlled.

  In this embodiment, the case where two electric double layer capacitors are used as the capacitor has been described. However, the same effect can be obtained even when three or more electric double layer capacitors are used. Further, regarding the capacitance of the electric double layer capacitor, any combination of capacitances is possible as long as the magnitude relationship of the capacitances is maintained. Further, all capacitors can be configured with the same capacitance by the configuration of the switching means.

[Other Examples]
In the above-described embodiment, the solar battery is used as the charging power and the electric double layer capacitor is used as the charging circuit capacitor. However, other charging circuits such as commercial power and a conventional storage battery may be used. When the received power is large capacity, start charging a plurality of charging circuits at once, supply the output by connecting to the load sequentially from the charged charging circuit, and add the charging circuit to the specified capacitance Thus, operation can be started in a short time even for a large power load.

  Moreover, although the charge start state which is the object of the present invention has been described, all the capacitors provided are charged, and when the power for charging is stopped, for example, all the capacitors are connected in parallel or used in advance. A plurality of capacitors can be used effectively depending on whether power is supplied from the capacitors one by one in the set order.

  Of course, the receiving power source may be another DC power source such as a commercial AC power source via an AC / DC converter, or if the load is AC, the DC power that is output via the DC / AC converter. It is also possible to obtain.

  Using a charging circuit for each of a plurality of capacitors having a capacitance obtained by dividing a capacitance required for charging, first, the charging circuit having a small capacitance is fully charged to supply DC power to the load, and then By sequentially charging the remaining capacitors and supplying DC to the load, it is easy to supply power to a large power load in a short time, so even if it is a weak received power like a solar cell, It can be applied to applications where a short-time power supply is necessary or indispensable.

It is explanatory drawing which showed one Embodiment of the functional block in the direct-current power supply device using a charging circuit. Example 1 It is explanatory drawing which shows one form of the voltage supplied to the load in FIG. Example 1 It is explanatory drawing which showed one Embodiment of the functional block in the direct-current power supply device using a charging circuit. (Example 2) It is explanatory drawing which showed one Embodiment of the functional block in SWC (capacitor selection means) of FIG. (Example 3) It is explanatory drawing which showed one Embodiment of the functional block in SWC (capacitor selection means) different from FIG. Example 4 It is explanatory drawing which showed one Embodiment of the functional block in SWS (electric power supply selection means) of FIG. (Example 5) It is explanatory drawing which showed one Embodiment of the functional block in the direct-current power supply device at the time of applying the functional block of FIG. (Example 6) It is explanatory drawing which shows one form of the voltage supplied to the load in FIG. (Example 6) It is explanatory drawing which showed an example of the functional block in the conventional DC power supply device using a charging circuit.

Explanation of symbols

1 Solar cell 2, 20 Load 3 C _SM (Accumulator)
4 C _LG (capacitor)
5, 30, 50 SWC (capacitor selection means)
6, 60 SWS (power supply selection means)
11 Voltage detection unit 12 Switching control unit 13, 21 CPU
14 High power load drive unit 22 ROM
24 Wireless LSI
31 SWc (switch)
32 Solenoid 33, 54 TR (Transistor)
53 Photocoupler 61, 62 Output adjustment circuit 63 Voltage monitoring circuit 64 Gate circuit

Claims (1)

At least two charging circuits each including a capacitor, capacitor selecting means for selecting at least one of the charging circuits to be charged, and at least one of the charging circuits connected to a load and supplying DC power A charging circuit for charging completion by controlling the power supply selection means, and when the charging completion is detected with a predetermined detection voltage by charging the related charging circuit by controlling the power supply selection means and the capacitor selection means. A DC power supply device comprising: a control means for sequentially connecting to a load and supplying DC power at a predetermined adjustment voltage;
The power supply selection means corresponds to each of the capacitors, inputs the respective storage voltage, and outputs the stored voltage as a supply voltage to the load at a predetermined adjustment voltage when receiving a corresponding switching signal. An output adjustment circuit that detects a voltage that enables complete driving of a predetermined load when charging starts with a monitoring voltage that is set between the detection voltage and the adjustment voltage, and from the voltage monitoring circuit, the voltage monitoring circuit A DC power supply device comprising: a gate circuit that drives the output adjustment circuit to output the supply voltage when receiving a monitoring voltage detection notification.

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