JP2011182598A - Device for supplying electric power, mobile information apparatus, and method for supplying electric power - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the efficiency of charging of a mobile information apparatus, by mounting a sub-battery for electric power generated such as photovoltaic power generation in addition to a main battery, and independently performing charging control of the main battery and the sub-battery. <P>SOLUTION: A device for supplying electric power includes: a first electric power supply part with the main battery 16, a main charging system 15 to charge the main battery, and a first switcher to control the supply of electric power from the main battery; and a second electric power supply part with the sub-battery 20, a sub-charging system 19 to charge the sub-battery, and a second switcher to control the supply of electric power from the sub-battery. In this device, a control unit to control ON/OFF of the first switcher and the second switcher is provided. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power supply device, a portable information device, and a power supply method, and more particularly to a power supply device, a portable information device, and a power supply method including a main battery and a sub battery.

  In recent years, due to an increase in power consumption due to higher functionality of portable devices, system control such as power saving operation is performed, and the average operating power is reduced to effectively use power of a main battery such as a lithium ion secondary battery. In addition, by incorporating power generation circuits using natural energy, such as solar power generation, vibration power generation using piezoelectric elements, and power generation using electromagnetics, into mobile terminals, studies are being made to enable further power supply in addition to the main battery. It has been broken.

  As such an example, Patent Document 1 and Patent Document 2 have proposed circuits using solar power generation. However, the current power conversion efficiency by solar power generation is not sufficient, and the area of the solar cell is limited when it is incorporated into the case of a portable terminal. Thus, a method for securing the area has been devised. For example, methods for improving solar power generation efficiency (Patent Documents 3 and 4) and enabling stable power supply from solar cells (Patent Document 5) have been proposed.

  On the other hand, a method of supplying power by monitoring generated power (Patent Document 3) has been proposed. This is a method of directly charging the main battery from the power generation circuit provided in the portable terminal. The voltage of the power generation circuit and the main battery is monitored, and the power is output from the power generation circuit only when the output voltage of the power generation circuit is higher than the voltage of the main battery. It is set as the structure which supplies. In addition, the charging circuit and the power generation circuit of the main battery are separately configured, and a power generation circuit corresponding to a small amount of power generation is designed to improve the charging efficiency. However, in this configuration, the power supply from the power generation circuit is limited to a good situation (for example, outdoors in fine weather), the power supply from the power generation circuit is difficult to be performed unless the voltage of the main battery is reduced, and the power generation circuit Since the FET is always turned on or passes through a diode, a loss (voltage drop due to an ON resistance or Vf of the diode) is generated, and it cannot be said that a small amount of generated power is always effectively utilized.

JP 2001-308356 A JP 2004-140521 A JP 2007-97330 A JP 2008-85777 A JP 2009-112097 A

  The efficiency of solar power generation, which is currently increasing, cannot be said to be sufficient, and there is a growing debate about how to improve power generation efficiency, and there is not much discussion on charging control methods and power supply methods. .

  Therefore, in the present invention, in a portable information device, in addition to a conventional main battery such as a lithium secondary battery, a sub-battery for generated power such as solar power generation is mounted, and charging control of the main battery and the sub-battery is independent of each other. It aims at improving charging efficiency by doing. Furthermore, the purpose of using the power is limited at the time of power saving operation such as standby operation, so that it is always charged regardless of the magnitude of the power, and the purpose is to improve the charging efficiency and effectively use the generated power.

A power supply apparatus according to the present invention includes a first power supply unit including a main battery, a main charge system for charging the main battery, and first switch means for controlling power supply from the main battery; ,
A sub-battery, a sub-charge system for charging the sub-battery, and a second power supply unit including a second switch means for controlling power supply from the sub-battery,
The power supply apparatus includes a control unit that controls on / off of the first switch unit and the second switch unit.

A power supply method according to the present invention includes a first power supply unit including a main battery, a main charge system for charging the main battery, and first switch means for controlling power supply from the main battery; ,
A power supply apparatus comprising: a sub-battery; a sub-charge system that charges the sub-battery; and a second power supply unit that includes a second switch unit that controls power supply from the sub-battery. A power supply method,
During normal operation, turn on the first switch means, turn off the second switch means,
In the power saving operation, the first switch means is turned off and the second switch means is turned on.

  According to the present invention, the main battery charging system and the sub-battery charging system are connected to each other through the switch unit to supply power to the system, so that the sub-battery is charged from the power generation unit. In some cases, regardless of the power generated by the power generation means, the sub battery can be charged independently of the voltage on the main battery side. Furthermore, almost all of the power generated by the power generation means is charged in the sub-battery, and the charging efficiency can be improved. Since the sequence for turning on the switch means is limited to the time of power saving operation, in the OFF state, the battery is always charged regardless of the magnitude of the power, and the power can be used up effectively.

It is a figure which shows one Embodiment of the charge control apparatus provided with the electric power generation circuit concerning this invention. It is a switch switching flowchart according to the portable terminal operation | movement of the charging circuit and auxiliary | assistant charging / discharging circuit of FIG. 3 is a timing chart showing the ON / OFF state of switch control in the flowchart of FIG. 2.

  FIG. 1 shows an embodiment of a power supply device including a power generation circuit according to the present invention.

  In FIG. 1, the first power supply unit 11 includes a main battery 16 and a charging circuit including a main charge system 15 and a switch SW1 (17) as a switch means. The charging circuit charges the main battery 16 mounted on the portable device. The main battery 16 supplies system power to the portable device during normal operation and power saving operation. The switch SW1 (17) enables control of the system power supply path. The switch SW1 (17) is configured by an FET or a transistor, and is controlled by the CPU 14 or / and the main charge system 15 as a control unit.

  The second power supply unit 12 includes a sub-battery 20 and an auxiliary charging circuit including a sub-charging system 19 and a switch SW2 (21) as a switching unit. The auxiliary charging circuit performs auxiliary charging to the sub battery 20. The switch SW2 (21) enables control of the system power supply path. System power supply from the sub-battery 20 is performed only during power saving operation. The switch SW2 (21) is constituted by an FET or a transistor, and is controlled by the CPU 14 and / or the subcharge system 19.

  The main battery 16 is charged from the AC adapter 13 as the power supply means via the main charge system 15 or from the power generation circuit 18 such as solar power generation or vibration power generation as the power generation means via the subcharge system 19. Done. Charging the sub-battery 20 is performed via a sub-charge system 19 from a power generation circuit 18 such as solar power generation or vibration power generation.

  Although not shown, the main charge system 15 and the sub charge system 19 are equipped with a logic control circuit that accepts serial communication and GPO control.

  By providing the switches SW1 and SW2, the main battery charge system 15 and the sub battery charge system 19 can control charging independently of the battery 16 and the sub battery 20, and also supply power to the system independently. It is possible. The switches SW1 and SW2 are controlled by the CPU or the respective battery systems 15 and 19.

  When charging the sub-battery 20 from the power generation circuit 18, the sub-battery 20 can be controlled independently by turning off the switch SW2, regardless of the voltage on the main battery side. Furthermore, almost all of the power generated by the power generation circuit, except for the consumption of the sub-battery charge system 19, is charged in the sub-battery 20, so that the charging efficiency can be improved.

  The power supply from the sub-battery 20 to the system is performed only when the portable device is in power saving operation. That is, the switch SW2 is turned on only when power is supplied from the sub battery 20.

  The output of the power generation circuit proposed in Patent Document 3 is such that the FET is always ON or connected to the system by a diode, and power is supplied when the output is at a higher voltage than the system side. In the present embodiment, the sub-battery charging by the power generation circuit 18 is disconnected from the system, so that the power is always charged regardless of the power level of the power generation circuit 18 and the power can be used effectively.

  In the present embodiment, the main battery 16 and the sub battery 20 are switched as the power supply source in accordance with the operation of the mobile terminal.

  During normal operation, for example, when the system power consumption is larger than the generated power such as a call / transmission, power is supplied to the system only from the main battery 16 with the switch SW1 (17) turned on and the switch SW2 (21) turned off. At this time, the generated power is always charged to the sub-battery 20 regardless of the magnitude of the power.

  When the power consumption of the portable terminal is smaller than the generated power, for example, in a standby state, the switch SW1 (17) is turned off and the switch SW2 (21) is turned on to supply power to the system only from the sub battery 20. Done. When the mobile terminal returns to normal operation again, the switch SW1 is turned on and the switch SW2 is turned off.

  In this way, by switching the switches SW1 and SW2 according to the operation status of the portable device, the main battery 16 and the sub battery 20 can be charged and discharged independently, and even with weak generated power such as solar power generation, it is always possible. Charging the sub-battery 20 improves charging efficiency, and it is possible to minimize loss by turning on the switch SW2 only when power is supplied from the sub-battery 20 by the operation of the mobile terminal. .

  In this configuration, the main battery 16 can be charged from the power generation circuit 18.

  In this embodiment, since the outflow current from the sub battery charge system 19 and the sub battery 20 is smaller than the normal operation, for example, when the portable terminal is not activated and the voltage of the main battery 16 is lower than the voltage of the sub battery 20, the switch Both SW1 and switch SW2 are turned ON, and a charging current can be supplied from the subcharge system 19 or the subbattery 20 to the main battery 16. When the voltage of the main battery 16 rises to the system startable voltage, the switch SW2 is turned off and power is supplied from the main battery 16 to ensure safety.

  FIG. 2 shows a switch switching flowchart according to the mobile terminal operation of the charging circuit 11 and the auxiliary charging / discharging circuit 12 of FIG.

  The mobile terminal has been activated and is operating normally (step S31). At this time, the system power is supplied only from the main battery, and the sub battery is being charged or stopped. It is determined whether or not a transition is made from a normal operation to a power saving operation (step S32), and a transition is made to a power saving operation (step S32: Yes, step S33), and whether power can be supplied (power supply) from the sub battery 20 to the system. Is determined (step S34). If it is determined that the condition for sub battery power supply is satisfied (step S34: Yes), the switches SW1 and SW2 are controlled to stop power supply from the main battery and supply power from the sub battery (power supply). Supply) is started (step S35). Thereafter, it is determined whether or not a transition is made from a power saving operation to a normal operation (step S37). When a transition is made to a normal operation (step S37: Yes), the switches SW1 and SW2 are controlled again to supply system power (power supply) (Supply) is switched from the sub-battery to the main battery (step S38), and the normal operation is performed (step S39).

  When it is determined that the sub battery cannot supply power to the system during the transition from the normal operation to the power saving operation (step S34: No), the power supply from the main battery is continued without controlling the switches SW1 and SW2 ( Step S36), the sub battery continues to be charged. At this time, if the transition to the normal operation is not made (step S37: No), it is determined again whether power can be supplied from the sub battery (step S34).

  Here, the operation flow for always monitoring the sub-battery during the power saving operation is used, but this flow may be omitted. In other words, the flow may determine whether switching is possible only once when entering the power saving operation.

  FIG. 3 is a timing chart showing ON / OFF states of the switches SW1 and SW2 in the flowchart of FIG.

  Here, the switches SW1 and SW2 as switching means are FETs, and the parasitic diode directions of the switches SW1 and SW2 are the anode on the battery side and the cathode on the system side (see FIG. 3: lower right). Further, it is assumed that the main battery voltage is V1, the sub-battery voltage is V2, and V1> V2.

  When transitioning from the normal operation to the power saving operation, the power supply from the main battery is stopped and the power supply from the sub battery is started (FIG. 2: step S35). The switches SW1 and SW2 are controlled from the switch SW1: ON, the switch SW2: OFF to the switch SW1: OFF, and the switch SW2: OFF (FIG. 3: T1). At this time, both the switch SW1 and the switch SW2 are in the OFF state, but the system is in a power saving operation, so that power supply by a parasitic diode can be expected. Then, the switch SW1: OFF and the switch SW2: ON are set, and power supply from the sub battery 20 is started (FIG. 3: T2).

  Next, when a transition is made from the power saving operation to the normal operation, when a path is opened so that system power can be supplied from the sub battery 20 to the main battery 16 (FIG. 2: step S38), from the switch SW1: OFF, the switch SW2: ON , Switch SW1: OFF, switch SW2: OFF (FIG. 3: T3). At this time, the switches SW1 and SW2 are both in the OFF state as described above, but since the system is in a power saving operation, power supply by a parasitic diode can be expected. Then, the switch SW1: ON and the switch SW2: OFF are set, and after the power supply from the main battery 16 is started, the operation is shifted to the normal operation (FIG. 3: T4).

  As described above, the switches SW1 and SW2 are not turned on at the same time, and the backflow current of the main battery 16 and the sub battery 20 is not generated, so that safety can be ensured.

  In addition, when preventing a backflow current other than the switches SW1 and SW2, a switching circuit may be provided instead of the switches SW1 and SW2 as the switch means. That is, the diode OR connection is made possible by combining the output voltages from the main battery and the sub battery.

  The power supply apparatus of this embodiment is suitably used for a power supply apparatus of portable information equipment such as a mobile phone, a game machine, and a notebook personal computer.

  While typical embodiments of the present invention have been described above, the present invention can be carried out in various other forms without departing from the spirit or main features defined by the claims of the present application. Can do. Therefore, the above-described embodiment is merely an example and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not restricted by the description or the abstract. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  A part or all of the above embodiment can be described as in the following supplementary notes, but is not limited to the following configuration.

(Supplementary Note 1) A first power supply unit including a main battery, a main charge system for charging the main battery, and first switch means for controlling power supply from the main battery;
A sub-battery, a sub-charge system for charging the sub-battery, and a second power supply unit including a second switch means for controlling power supply from the sub-battery,
A power supply apparatus comprising: a control unit that controls on / off of the first switch means and the second switch means.

(Supplementary note 2) The power supply apparatus according to supplementary note 1, wherein the main charge system charges the main battery by power supply means, and the subcharge system charges the sub battery by power generation means.

(Additional remark 3) The said control part switches the electric power supply from the said main battery and a subbattery, The electric power supply apparatus of Additional remark 1 or 2 characterized by the above-mentioned.

(Additional remark 4) The said control part switches electric power supply switching from the said main battery and the said sub-battery according to the system load condition of the apparatus which supplies electric power. Power supply device.

(Additional remark 5) The 1st electric power supply part provided with the main battery, the main charge system which charges this main battery, and the 1st switch means which controls the electric power supply from this main battery,
A power supply apparatus comprising: a sub-battery; a sub-charge system that charges the sub-battery; and a second power supply unit that includes a second switch unit that controls power supply from the sub-battery. A power supply method,
During normal operation, turn on the first switch means, turn off the second switch means,
A power supply method for turning off the first switch means and turning on the second switch means during a power saving operation.

(Supplementary note 6) The power supply method according to supplementary note 5, wherein the main charge system charges the main battery by power supply means, and the sub-charge system charges the sub battery by power generation means.

(Supplementary note 7) The power supply method according to supplementary note 5 or 6, wherein the first and second switch means are turned off when switching between the normal operation and the power saving operation.

(Supplementary note 8) The power supply method according to any one of supplementary notes 5 to 7, wherein switching of power supply from the main battery and the sub battery is performed according to a system load state of a device that supplies power. .

(Appendix 9)
A portable information device comprising the power supply device according to any one of appendices 1 to 4.

  The present invention is suitably used for a power supply device of portable information equipment such as a mobile phone, a game machine, and a notebook personal computer.

11 1st power supply part 12 2nd power supply part 13 AC adapter 14 CPU
15 Main charge system 16 Main battery 17 Switch SW1
15 Main charge system 18 Power generation circuit 19 Sub charge system 20 Sub battery 21 Switch SW2

Claims (9)

A first power supply unit comprising a main battery, a main charge system for charging the main battery, and first switch means for controlling power supply from the main battery;
A sub-battery, a sub-charge system for charging the sub-battery, and a second power supply unit including a second switch means for controlling power supply from the sub-battery,
A power supply apparatus comprising: a control unit that controls on / off of the first switch means and the second switch means.   The power supply apparatus according to claim 1, wherein the main charge system charges the main battery by power supply means, and the subcharge system charges the sub battery by power generation means.   The power supply apparatus according to claim 1, wherein the control unit switches power supply from the main battery and the sub battery.   4. The power according to claim 1, wherein the control unit switches power supply switching from the main battery and the sub battery according to a system load state of a device that supplies power. Feeding device. A first power supply unit comprising a main battery, a main charge system for charging the main battery, and first switch means for controlling power supply from the main battery;
A power supply apparatus comprising: a sub-battery; a sub-charge system that charges the sub-battery; and a second power supply unit that includes a second switch unit that controls power supply from the sub-battery. A power supply method,
During normal operation, turn on the first switch means, turn off the second switch means,
A power supply method for turning off the first switch means and turning on the second switch means during a power saving operation.   The power supply method according to claim 5, wherein the main charge system charges the main battery by power supply means, and the subcharge system charges the sub battery by power generation means.   7. The power supply method according to claim 5, wherein the first and second switch means are turned off when switching between the normal operation and the power saving operation.   The power supply method according to any one of claims 5 to 7, wherein the power supply switching from the main battery and the sub battery is performed according to a system load state of a device that supplies power.   The portable information device provided with the electric power supply apparatus of any one of Claim 1 to 4.

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