JP2006166577A - Power supply control method and power unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply control method and a power unit which can lessen loss and are low-cost by lessening the change of a current taken out of a generator even with sudden change of a load. <P>SOLUTION: This power unit has a generator, an accumulating device, and a control unit. The generator sets its output power to be lower than the maximum power consumption of the load and to be larger than the specified power consumption during operation of the load. Then, the accumulating device is connected in parallel with the generator. Besides, the control unit so controls the system as to perform the power supply to the load by the discharge of the accumulating device when the power consumption of the load is larger than the specified power consumption of the load, and to perform the power supply from the generator to the load when the power consumption of the load is under the specified power consumption, and also to perform the charge to the accumulating device by the current from the generator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power supply control method and a power supply device, and in particular, charges a DC voltage output of a power generation device such as a fuel cell to a storage device such as a secondary battery and supplies power to a load that fluctuates via a constant voltage power supply. For example, the present invention relates to power optimization of a power supply device that supplies power to an image forming apparatus.

  Many of the conventional image forming apparatuses use a commercial power source. Therefore, electric energy from the commercial power source is consumed even during standby, which is not preferable in terms of resource saving and environmental protection. Therefore, conventionally, for example, Patent Document 1 and Patent Document 2 have proposed an image forming apparatus that employs a solar battery power supply system that charges a secondary battery with a solar battery. However, the power supply by these solar cells is based on the premise that it will be exposed to sunlight. For this reason, a separate mechanism for reducing energy during nighttime and the like is required, which increases the size and cost of the device. Therefore, a fuel cell is attracting attention. Hereinafter, this fuel cell will be described.

Currently, a fuel cell is a power source that extracts the energy generated when water is produced by chemically reacting hydrogen and oxygen in the form of electric power, and is attracting attention as clean energy. However, since the output resistance value of the fuel cell is larger than the output resistance value R of the secondary battery or the electric double layer capacitor, a large current I flows when the load increases when power is directly supplied to a load with large fluctuations. The loss W at the output resistance calculated from the following formula becomes large and the efficiency is poor.
W = I ² * R

For this reason, efficiency can be improved by charging a secondary battery or an electric double layer capacitor and averaging the current.
Japanese Unexamined Patent Publication No. 7-15889 JP 7-271249 A

  However, fuel cells, secondary batteries, and electric double layer capacitors have higher prices as their capacity increases, so even if sufficient capacity is required to drive the load device, capacity is as much as possible in view of cost. Is desirable to be small. It is also desirable to create a fuel cell system with a minimum scale that can continuously drive a load device. Furthermore, since the output voltage of the fuel cell is unstable, it is generally supplied to the load after the voltage is stabilized by a constant voltage power source.

  The present invention is intended to solve these problems, and a power supply control method and a power supply device that can reduce a change in current taken out from a power generation device even in a sudden load change, reduce loss, and are less expensive. The purpose is to provide.

  In order to solve the above problem, according to the power supply control method of the present invention, which controls the power supply from the power supply device configured by connecting the power generation device and the power storage device in parallel to the load, the output power of the power generation device is reduced. The power consumption is set lower than the maximum power consumption of the load supplying the power and larger than the predetermined power consumption during the operation of the load. When the power consumption of the load is larger than the predetermined power consumption of the load, power is supplied to the load by discharging the power storage device, and when the power consumption of the load is less than the predetermined power consumption of the load, The power is supplied to the power storage device with the current from the power generator. Therefore, even if the load fluctuates suddenly, the change in current taken out from the power generation device can be reduced and the loss can be reduced.

  In addition, a power supply device as another invention includes a power generation device, a power storage device, and a control unit. The power generation device is a power generation device that sets output power that is lower than the maximum power consumption of the load and larger than a predetermined power consumption during the operation of the load. The power storage device is connected in parallel with the power generation device. In addition, when the power consumption of the load is greater than the predetermined power consumption of the load, the control unit supplies power to the load by discharging the power storage device, and when the power consumption of the load is less than the predetermined power consumption of the load. Controls to supply power from the power generator to the load and to charge the power storage device with the current from the power generator. Therefore, it is possible to provide a low-cost power supply device that can reduce a change in current taken out from the power generation device even when the load is suddenly changed, and can reduce loss.

  Furthermore, the power supply device of the present invention is provided with a constant voltage power source that is connected in parallel to the load and that applies the input voltage to the load with a constant rated voltage if the input voltage applied to the load is equal to or lower than the rated voltage. As a result, a stable voltage can be supplied to the load.

  The predetermined power consumption of the load is preferably the average power consumption of the load. Furthermore, the power generation device is preferably a fuel cell. Further, the electricity storage device is preferably a secondary battery or an electric double layer capacitor.

  Furthermore, a temperature sensor that detects the surface temperature of the power storage device, and a charge state of the power storage device is detected based on a detection signal from the temperature sensor, and charging current supply is controlled according to the detected charge state of the power storage device. By providing the charge control circuit, efficient charge control can be performed.

  In addition, a current sensor that detects a charging current supplied to the power storage device is provided, and the charge control circuit detects a charge state of the power storage device based on a detection signal from the current sensor, and determines the detected charge state of the power storage device. The supply of charging current is controlled accordingly. Therefore, more efficient charge control can be performed.

  Furthermore, a switch is provided between the power generation device and the power storage device, and the opening and closing of the switch is controlled by the charge control circuit, so that the power storage device such as a secondary battery can be electrically disconnected from the power generation device such as a fuel cell. It is possible to eliminate unnecessary charging of the electricity storage device.

  In addition, a first switch is provided between the power generation device and the power storage device, and a second switch is provided between the power storage device and the constant voltage power source, and each switch opens and closes according to charge / discharge of the power storage device. When electricity storage devices such as secondary batteries can be electrically disconnected and are not required, current consumption with constant voltage power supplies can be eliminated, and unnecessary charging of electricity storage devices from power generators such as fuel cells can be eliminated. .

  Furthermore, it is preferable that the first switch and the second switch open and close in conjunction with each other.

  In addition, the load is a driving unit for performing recording of the recording device, and when the recording device starts recording and requires more power than the output power of the power generation device, power is supplied to the driving unit by discharging the power storage device. . Therefore, when performing continuous print output, even if the average power of a power generator such as a fuel cell is lower than the average power consumed by the drive means of the recording device that is the load, printing is performed with the power from the power storage device such as a secondary battery. The power generation capability of the power generation device such as a fuel cell can be lowered, and the price of the entire power supply device can be reduced by using an inexpensive fuel cell.

  In the power supply device of the present invention, the output power of the power generation device is set lower than the maximum power consumption of the load and larger than the predetermined power consumption during the operation of the load. An electricity storage device is connected in parallel to this power generation device. The control unit supplies power to the load by discharging the power storage device when the power consumption of the load is greater than the predetermined power consumption of the load, and from the power generator when the power consumption of the load is less than the predetermined power consumption of the load. Control is performed so that power is supplied to the load and the power storage device is charged by the current from the power generation device. Therefore, it is possible to provide a low-cost power supply device that can reduce a change in current taken out from the power generation device even when the load is suddenly changed, and can reduce loss.

First, a recording apparatus to which the power supply device of the present invention is applied will be described.
FIG. 1 is a schematic perspective view showing the configuration of a recording apparatus to which the power supply apparatus of the present invention is applied. An ink jet recording apparatus 10 which is an example of the recording apparatus shown in the figure is of a type in which a recording head cartridge 12 in which a recording head 11 and an ink tank as an ink supply source are integrated is loaded. The recording head cartridge 12 is fixed on a carriage 14 by a pressing member 13, and can reciprocate in the longitudinal direction along the shaft 15. Then, the ink droplets ejected from the recording head 11 reach the recording paper 17 whose recording surface is regulated by the platen 16 at a minute distance from the recording head 11 and form an image. A recording timing pulse corresponding to image data is supplied to the recording head 11 from an appropriate data supply source via a cable 18 and a terminal coupled thereto. One or a plurality of recording head cartridges 12 (two in the drawing) can be provided according to the ink color used. The carriage motor 19 is a motor for scanning the carriage 14 along the shaft 15, and the wire 20 is a wire for transmitting the driving force of the carriage motor 19 to the carriage 14. The line field motor 21 is a line feed motor that is coupled to the platen roller 16 to convey the recording paper 17, and the home position sensor 22 is a sensor that detects the home position of the carriage 14.

  Next, FIG. 2 is a block diagram showing the control circuit of the recording apparatus of FIG. 1 with respect to a control circuit for executing recording control of the ink jet recording apparatus which is an example of the recording apparatus of FIG. 1 having such a configuration. It explains using.

  The control circuit 30 of the ink jet recording apparatus, which is an example of the recording apparatus of FIG. 1 shown in FIG. 2, supplies power necessary for performing the recording operation of the recording apparatus, and corresponds to the power supply apparatus of the present invention. 31, a CPU 32 for executing operation control and data processing of the recording apparatus, a ROM 33 for storing a control program for the CPU 32 and various data for font processing, a RAM 34 for temporarily storing various data including received image data, and a host computer A data receiving unit 35 for taking in image data sent from an external device such as a DMA / RAM controller for transferring image data received by the data receiving unit 35 to the RAM 34 or controlling access from the CPU 32 to the RAM 34 36, an EEPROM or the like that stores printer-specific parameters Nonvolatile memory 37 is configured to include a head controller 40 for generating a transfer and heat pulse signal of the image data to the head driver 39 under the control of the head driver 39, CPU 32 for driving the recording head 38. Further, the carriage motor driver 41, the carriage motor 42, and the timing control unit 43 move the recording head 38 (this direction is referred to as a main scanning direction) by a control signal supplied from the CPU 32 and a recording timing pulse from an encoder or the like. Similarly, the line feed motor driver 44 and the line feed motor 45 are control systems that transport a recording medium such as recording paper (this direction is referred to as a sub-scanning direction) by a control signal supplied from the CPU 32. is there. The ink flow rate detection unit 46 counts the number of ink droplets (dots) ejected for recording within a predetermined time from the recording signal sent to the recording head 38 and supplies the ink droplets to the recording head 38 from the ink tank. The flow rate of the ink to be detected is detected.

Next, basic recording control in the recording apparatus of FIG. 1 will be described with reference to FIG.
First, the image data input from the host computer by the data receiving unit 35 is temporarily stored in the RAM 34 via the DMA / RAM controller 36, and the CPU 32 executes the control program stored in the ROM 33 so that the CPU 32 receives the received command, the image data, Perform character code analysis. Thereafter, the input image data is converted into recording data by the CPU 32 and sequentially stored in the RAM 34. The reception command includes recording control information, and recording is performed with the number of recording passes corresponding to the recording control information. The carriage motor 42 is driven by the carriage motor driver 41 when the development of the recording data for one line is completed or when a recording command (one reception command) is input from the host computer. Then, the recording data stored in the RAM 34 is transferred to the head driver 39 via the DMA / RAM controller 36 and the head controller 40 in synchronization with the recording timing pulse output from the timing control unit 43. Then, a heat pulse signal is sent from the head controller 40 to the head driver 39 to eject ink droplets from the recording head 38. When the recording for one line is completed, the line feed motor 45 is driven to perform a line feed, and a series of procedures is completed. By repeating such a procedure over one page of the recording paper, the recording operation for one page is completed.

  The power supply device of the present invention used in an ink jet recording apparatus which is an example of a recording apparatus that performs a recording operation by such basic recording control will be described below with specific numerical values. The following numerical values are for ease of explanation, and are not limited to these numerical values.

  As described above, since the ink jet recording apparatus ejects ink while reciprocating the head mounted on the carriage to form an image, the carriage starts to move as shown in FIG. 3 showing the current change characteristics during continuous printing. Therefore, an impulse instantaneous current of about 1.45 A is required. However, only a current of about 0.2 A is required in the standby state. On the other hand, during continuous printing, each time the carriage reciprocates, it fluctuates between 1.45 A and 0.2 A. On average, a current of about 0.7 A flows. If this operation is to be covered only by a fuel cell used as a power generator in the power supply device of the present invention, a fuel cell capable of extracting a current of 1.45 A is required, but it can be assisted by a secondary battery, an electric double layer capacitor or the like. For example, a fuel cell can perform continuous printing if it has a capacity to pass a current of 0.7 A.

  Here, the fuel cell used for the power generator in the power supply device of the present invention will be briefly described. The fuel cell is provided with electrodes such as carbon containing platinum as a catalyst on both surfaces of a membrane electrolyte, and one electrode (fuel electrode). ) Is supplied with a reducing agent such as hydrogen or methanol, and the other electrode (air electrode) is supplied with a reducing agent containing oxygen such as air. Hydrogen ions generated from hydrogen using platinum as a catalyst at the fuel electrode are propagated in the electrolyte from the fuel electrode to the air electrode, and electrons generated from hydrogen at the fuel electrode flow to the air electrode through an external load, and hydrogen ions are generated at the air electrode. Water is generated by oxygen, electrons, and oxygen, and electric energy is generated through a series of oxidation-reduction reactions to supply voltage to the outside. As can be seen from the current-voltage characteristic diagram of the fuel cell shown in FIG. 4, the more the current is extracted for the output impedance of the fuel cell, the lower the voltage of the fuel cell. From this characteristic diagram, the output impedance is about 16Ω.

Next, the power supply device of the present invention will be described.
FIG. 5 is a block diagram showing a circuit configuration of the power supply apparatus according to the first embodiment of the present invention. As shown in the figure, the power supply device 100 of the first embodiment is connected in parallel between the power generation device 101 such as the fuel cell described above, and the power generation device 101 and the ground, for example, a secondary battery, an electric double layer. An electric storage device 102 such as a capacitor, an anode includes a power generation apparatus 101, and a cathode includes a diode 103 connected to one terminal of a load 104 and one terminal of the electric storage device 102, respectively. The power supply device 100 having such a configuration is connected to a load 200 such as a line feed motor in the above-described ink jet recording apparatus. The output impedance of the power generator 101 is about 16Ω.

  According to the power supply apparatus 100 of the present embodiment having such a circuit configuration, the output voltage of the power generation apparatus 101 is 30 V as shown in FIG. Since the voltage drop of the diode 103 is about 1V, the cathode voltage of the diode 103 is 29V, while the power storage device 102 uses a voltage of 29V. When the load 200 consumes a current of 0.65 A, (the output voltage (30 V) of the power generation apparatus 101) − (voltage drop (1 V) at the diode) = 29 V, the voltage of the power storage device 102 becomes equal. The power storage device 102 is neither charged nor discharged. Next, when the load 200 consumes a current larger than 0.65 A, the output voltage of the power generation apparatus 101 is lower than the voltage of the power storage device 102 according to FIG. 4, so the power storage device 102 covers all the current consumed by the load. To discharge. On the other hand, when the load 200 consumes only a current of 0.65 A or less, since the output voltage of the power generation device 101 is higher than the voltage of the power storage device 102, the power storage device 102 is charged and all the current consumed by the load 200 is generated. Device 101 covers it. For example, since the standby current in the ink jet recording apparatus of FIG. 1 is 0.2 A, the output voltage of the power generation apparatus 101 is 37 V obtained by subtracting the voltage drop (1 V) at the diode 103 from about 38 V, and the storage device 102 is 29 V. Since the difference is 8V and the output impedance is about 16Ω, the charging current of the electricity storage device 102 is 0.5A (= 8V / 16Ω). That is, as described above, charging and discharging are performed by setting circuit constants such as the voltage of the power generation apparatus 101, the internal resistance of the power generation apparatus 101, the voltage of the storage device 102 such as a secondary battery and an electric double layer capacitor, and the voltage drop of the diode 103. By optimally setting, it is possible to automatically switch between charging and discharging without providing a control circuit for switching between charging and discharging. If the capacity of the secondary battery is determined by paying attention only to the charging current, the range of 10C to 0.05C is a practical limit, that is, the capacity of the secondary battery is practically in the range of 0.05AH to 10AH. It is a limit. This is because when the capacity of the secondary battery is 0.05 AH or less, charging is completed in a short time, but problems of heat generation during charging and battery life occur. In addition, if the capacity of the secondary battery is 10 AH or more, there is no problem in terms of heat generation and life, but it takes about 20 hours to complete charging, and in terms of price, volume, and weight.

  Therefore, according to the power supply control method by the power supply apparatus 100 of the present embodiment, the output power of the power generation apparatus 101 is set lower than the maximum power consumption of the load 200 and larger than the average power consumption during the operation of the load 200. For example, when an impulse instantaneous current of about 1.45 A flows at the beginning of the movement of the carriage shown in FIG. 3 when the average power consumption is exceeded, the power generation device 101 has a current of 0.7 A by assisting with the power storage device 102. If there is a capacity to flow, continuous printing can be performed.

  Next, FIG. 6 is a block diagram showing a circuit configuration of a power supply apparatus according to the second embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 5 denote the same components. As shown in the figure, the power supply device 100 of the second embodiment is connected in parallel to a load 200 in addition to the configuration of the power supply device 100 of the first embodiment shown in FIG. A constant voltage power supply 104 is included. According to the power supply apparatus 100 of the present embodiment having such a configuration, the constant voltage power supply 104 is supplied with a voltage obtained by subtracting a voltage drop (1V) at the diode 103 from the voltage generated by the power generation apparatus 101. The constant voltage power supply 104 supplies the supplied input voltage to the load 200 at a constant voltage lower than the rated voltage of the constant voltage power supply 104. When the load 200, for example, an ink jet recording apparatus, starts a printer operation, current is supplied from the output terminal of the constant voltage power source 104 to the load 200, and the output voltage of the power generation apparatus 101 decreases. On the other hand, when the operation of the load 200 is stopped, the supply of current from the output terminal of the constant voltage power supply 104 to the load 200 is stopped, and the output voltage of the power generator 101 is increased.

  Next, FIG. 7 is a block diagram showing a circuit configuration of a power supply device according to a third embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 6 denote the same components. The power supply apparatus 100 according to the third embodiment shown in the figure uses a secondary battery 105 as the power storage device 102 in the configuration of the power supply apparatus 100 according to the second embodiment shown in FIG. A temperature sensor 106 that detects the surface temperature of the battery 105, a charge control circuit 107 that detects the charge state of the secondary battery 105 based on a detection signal from the temperature sensor 106, and controls opening and closing of a switch 108, which will be described later; A switch 108 provided between the battery 105 and the cathode of the diode 103 is included. According to the power supply apparatus 100 of the present embodiment having such a configuration, the temperature sensor 106 detects the surface temperature of the secondary battery 105, and the charge control circuit 107 detects the secondary battery 105 based on the detection signal. When the state of charge is detected, for example, when the fully charged state of the secondary battery 105 is detected, the switch 108 is opened to stop charging.

  Next, FIG. 8 is a block diagram showing a circuit configuration of a power supply device according to a fourth embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 7 denote the same components. The power supply device 100 according to the fourth embodiment shown in the figure is a current sensor that detects the current supplied to the secondary battery 105 in the configuration of the power supply device 100 according to the third embodiment shown in FIG. 109. According to the power supply apparatus 100 of the present embodiment having such a configuration, the current supplied to the secondary battery 105 is detected by the current sensor 109, and the charge control circuit 107 is based on the detection signal. For example, when a fully charged state of the secondary battery 105 is detected, the switch 108 is opened to stop charging.

  Next, FIG. 9 is a block diagram showing a circuit configuration of a power supply device according to a fifth embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 6 denote the same components. The power supply device 100 of the fifth embodiment shown in the figure uses a secondary battery 105 as the power storage device 102 in the configuration of the power supply device 100 of the second embodiment shown in FIG. Switches 110 and 111 are provided between the diode 101 and the anode of the diode 103 and between the cathode of the diode 103 and the constant voltage power source 104, respectively. According to the power supply device 100 of the present embodiment having such a configuration, charging / discharging of the secondary battery 105 is controlled by opening and closing the switches 110 and 111 according to the charge state of the secondary battery 105. Further, by providing the two switches 110 and 111 in this way, the secondary battery 105 can be electrically disconnected, and when the secondary battery 105 is not required, current consumption in the constant voltage power source 104 is eliminated. In addition, by eliminating unnecessary charging of the secondary battery 105 from the power generation apparatus 101, the lifetime of the constant voltage power supply 104 and the secondary battery 105 can be extended.

  As shown in FIG. 10, the switches 110 and 111 are opened / closed in conjunction with each other, and the switch 111 is opened in conjunction with the switch 110 being closed. When the battery is fully charged, the switch 110 is closed in conjunction with the completion of the charging from the power generator 101 to discharge the secondary battery 105 and supply the current to the load 200. Do.

  If the capacity of the secondary battery is determined by paying attention only to the charging current, the range of 10C to 0.05C becomes a practical limit. That is, the practical limit of the secondary battery capacity is in the range of 0.05 AH to 10 AH. If it is 0.05 AH or less, charging is completed immediately, but heat generation during charging and battery life problems occur. On the other hand, if it is 10 AH or more, it is satisfactory in terms of heat generation and life, but it takes about 20 hours to complete charging, and it is problematic in terms of price, volume, and weight. Furthermore, since the average current of the fuel cell exceeds the average current consumed by the printer, any number of sheets can be operated continuously. However, if the number of continuous sheets is limited to 100 sheets, for example, even if the average current of the fuel cell is lower than the average current consumed by the printer, the printing operation can be performed with the current from the secondary battery, and the power generation capacity of the fuel cell is further reduced. be able to.

  The present invention is not limited to the above-described embodiments, and it goes without saying that various modifications and substitutions are possible as long as they are described within the scope of the claims.

1 is a schematic perspective view illustrating a configuration of a recording apparatus to which a power supply device of the present invention is applied. FIG. 2 is a block diagram illustrating a control circuit of the recording apparatus in FIG. 1. It is a characteristic view which shows the electric current change during the continuous printing by a recording device. It is a current-voltage characteristic view of a fuel cell. It is a block diagram which shows the circuit structure of the power supply device which concerns on the 1st Example of this invention. It is a block diagram which shows the circuit structure of the power supply device which concerns on the 2nd Example of this invention. It is a block diagram which shows the circuit structure of the power supply device which concerns on the 3rd Example of this invention. It is a block diagram which shows the circuit structure of the power supply device which concerns on the 4th Example of this invention. It is a block diagram which shows the circuit structure of the power supply device which concerns on the 5th Example of this invention. It is a block diagram which shows the circuit structure of the power supply device when the switch of FIG. 9 interlock | cooperates.

Explanation of symbols

100; power supply device; 101; power generation device; 102; power storage device;
103; diode, 104; constant voltage power supply, 105; secondary battery,
106; temperature sensor; 107; charge control circuit;
108, 110, 111; switch, 109; current sensor,
200; load.

Claims (13)

In a power supply control method for controlling power supply to a load from a power supply device configured by connecting a power generation device and a power storage device in parallel,
The output power of the power generator is set lower than the maximum power consumption of the load and larger than a predetermined power consumption during operation of the load,
When the power consumption of the load is greater than the predetermined power consumption of the load, power is supplied to the load by discharging the power storage device,
When the power consumption of the load is less than the predetermined power consumption of the load, power is supplied from the power generation device to the load, and the power storage device is charged by a current from the power generation device. A power supply control method. A power generator configured to set output power lower than the maximum power consumption of a load supplying power and larger than a predetermined power consumption during operation of the load;
An electricity storage device connected in parallel with the power generation device;
When the power consumption of the load is greater than the predetermined power consumption of the load, power is supplied to the load by discharging the power storage device, and when the power consumption of the load is less than the predetermined power consumption of the load And a control unit that controls to supply power from the power generation device to the load and to charge the power storage device with a current from the power generation device.   3. A constant voltage power supply that is connected in parallel to the load and that applies a constant rated voltage to the load when the input voltage applied to the load is equal to or lower than a rated voltage is provided. Power supply.   The power supply device according to claim 2, wherein the predetermined power consumption of the load is an average power consumption of the load.   The power supply device according to claim 2, wherein the power generation device is a fuel cell.   The power supply device according to claim 2, wherein the power storage device is a secondary battery or an electric double layer capacitor.   A temperature sensor that detects a surface temperature of the power storage device, and a charge state of the power storage device is detected based on a detection signal from the temperature sensor, and a supply of a charging current is controlled according to the detected charge state of the power storage device The power supply device according to any one of claims 2 to 6, further comprising a charge control circuit for performing the operation.   A current sensor for detecting a charging current supplied to the power storage device is provided, and the charge control circuit detects a charge state of the power storage device based on a detection signal from the current sensor, and detects the detected charge of the power storage device The power supply device according to any one of claims 2 to 7, wherein supply of a charging current is controlled according to a state.   The power supply device according to claim 7 or 8, wherein a switch is provided between the power generation device and the power storage device, and the opening and closing of the switch is controlled by the charge control circuit.   A first switch is provided between the power generation device and the power storage device, and a second switch is provided between the power storage device and the constant voltage power source, and each switch opens and closes according to charge / discharge of the power storage device. Item 3. The power supply device according to Item 2.   The power supply device according to claim 10, wherein the first switch and the second switch open and close in conjunction with each other.   The power supply apparatus according to claim 2, wherein the load is a driving unit for performing recording of the recording apparatus. The power supply device according to claim 12, wherein when the recording device starts recording and requires more power than the output power of the power generation device, power is supplied to the driving unit by discharging the power storage device.

Images