JP2006060892A - Portable power supply device and charge control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a portable power supply device and a charge control method therefor, wherein stable charging from a terminal for output is enabled. <P>SOLUTION: The portable power supply device includes a DC input/output terminal 17 for input of direct-current power from a direct-current power source and output of direct-current power to a load; an internal accumulator 18 that can be charged with direct-current power from the DC input/output terminal 17; a charge control circuit 12 for controlling the input of the direct-current power to the internal accumulator 18 so that the voltage of input to the internal accumulator 18 becomes equal to or lower than a predetermined value; switching circuits 14 and 15, that switch between a first path that does not go through via the charge control circuit and a second path that does not go through via the charge control circuit to connect the DC input/output terminal 17 and the internal accumulator 18; and a voltage detector 19a for detecting the voltage of the DC input/output terminal 17. Based on the voltage of the DC input/output terminal 17 detected by the voltage detector 19a, the switching circuits 14 and 15 are controlled by CPU 11. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a portable power supply device and a charge control method thereof, and more particularly to a portable power supply device that can be charged from a DC power supply and a charge control method thereof.

  Generally, a portable power supply device is equipped with a storage battery as a built-in battery. Such a power supply device can drive a connected electrical appliance or the like by discharging DC power stored in the storage battery. Therefore, for example, it is particularly used when a commercial power source cannot be used due to a power failure or the like or outdoors.

  On the other hand, the portable power supply device cannot be discharged when the built-in storage battery is consumed. Therefore, the storage battery needs to be charged.

As a method for charging a storage battery, there is conventionally a method of charging by acquiring DC power from a DC power source such as a solar battery (see Patent Document 1).
JP-A-9-121575

  However, since the conventional portable power supply device is provided separately from the charging terminal and the output (discharge) terminal, it cannot be charged from the output terminal.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a portable power supply device that enables stable charging from an output terminal and a charge control method thereof. It is.

  A portable power supply device according to an aspect of the present invention includes a first terminal for inputting DC power from a DC power source and outputting DC power to a load, and a storage battery that can be charged by DC power from the first terminal. And a charge control circuit for controlling the input of DC power to the storage battery so that the input voltage to the storage battery is equal to or lower than a predetermined value, and a first terminal via the charge control circuit between the first terminal and the storage battery. Switching means for switching and connecting the second path not via the charge control circuit, a first detection means for detecting the voltage at the first terminal, and detected by the first detection means Control means for controlling the switching means based on the voltage at the first terminal.

  Preferably, the switching means described above bypasses the first switch means provided in series with the charge control circuit on the power supply path between the first terminal and the storage battery, and the charge control circuit and the first switch means. And the 2nd switch means provided in order to electrically connect a 1st terminal and a storage battery is included. In this case, the control means controls conduction / non-conduction of the first switch means and the second switch means.

  Preferably, when the control unit determines that the voltage at the first terminal is higher than a predetermined value, the control unit sets the first switch unit to a conductive state, the second switch unit to a non-conductive state, and the voltage at the first terminal is If it is determined that the value is equal to or less than the predetermined value, the first switch means is turned off and the second switch means is turned on.

  Preferably, the battery pack further includes second detection means for detecting the voltage of the storage battery, and the control means has a voltage of the storage battery detected by the second detection means equal to or higher than the voltage of the first terminal detected by the first detection means. When it is determined that the first switch means is in a non-conductive state, the second switch means is in a conductive state.

  Further, when the control means determines that the voltage at the first terminal detected by the first detection means is higher than the voltage of the storage battery detected by the second detection means, the first switch means is turned on. It is desirable that the second switch means be in a non-conductive state.

  More preferably, an inverter unit for converting DC power from the storage battery into AC power and a second terminal provided for outputting the AC power converted by the inverter unit are further provided.

  A charge control method according to another aspect of the present invention includes a first terminal provided to input DC power from a DC power source and output DC power to a load, and DC power from the first terminal. A rechargeable storage battery, a charge control circuit for controlling the input of DC power to the storage battery so that the input voltage to the storage battery is below a predetermined value, and a power supply line between the first terminal and the storage battery A first switch circuit provided in series with the charge control circuit on the path; and a first switch circuit configured to bypass the charge control circuit and the first switch circuit and to electrically connect the first terminal and the storage battery. A charge control method for a portable power supply device comprising a two-switch circuit, wherein a detection step for detecting a voltage at a first terminal, and whether the voltage at the first terminal detected by the detection step is higher than a predetermined value To judge When the disconnection step and the determination step determine that the voltage at the first terminal is higher than a predetermined value, the first switch circuit is turned on and the second switch circuit is turned off. When the voltage at the first terminal is determined to be equal to or lower than a predetermined value, the first switch circuit is turned off and the second switch circuit is turned on.

  A charging control method according to still another aspect of the present invention includes a first terminal provided for inputting DC power from a DC power source and outputting DC power to a load, and DC power from the first terminal. , A charge control circuit for controlling the input of DC power to the storage battery so that the input voltage to the storage battery is below a predetermined value, and a power supply line between the first terminal and the storage battery The first switch circuit provided in series with the charge control circuit and the first control circuit and the first switch circuit are detoured to electrically connect the first terminal and the storage battery. A charge control method for a portable power supply device comprising a second switch circuit, comprising: a first detection step for detecting a voltage at a first terminal; a second detection step for detecting a voltage of a storage battery; and a first detection step. detection And determining whether the voltage at the first terminal is higher than the voltage of the storage battery detected at the second detection step, and the determination step determines that the voltage at the first terminal is higher than the voltage of the storage battery. When it is determined that the voltage is high, the first switch circuit is turned on and the second switch circuit is turned off, and the determination step determines that the voltage at the first terminal is equal to or lower than the voltage of the storage battery. And a step of bringing the first switch circuit into a non-conductive state and the second switch circuit into a conductive state.

  According to the present invention, DC power is input and output at the first terminal. As a result, it is possible to connect a DC power source and a load using DC power as a power source at a common terminal. Therefore, user convenience can be improved.

  Further, the first switch means and the second switch means are provided to control the conduction / non-conduction state. Thereby, it becomes possible to connect a storage battery and a 1st terminal via a charge control circuit, and to connect without a charge control circuit. Therefore, when charging a storage battery, it can pass through a charge control circuit and the stable charge is attained.

  Further, since the voltages of the first terminal and the storage battery are detected and the conduction / non-conduction state of the first switch means and the second switch means is controlled, it is possible to automatically switch between charging and discharging.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a block diagram of a portable power supply device according to an embodiment of the present invention.

  Referring to FIG. 1, the portable power supply according to the present embodiment includes a CPU for controlling the operation of each hardware by various execution programs stored in advance in a built-in ROM (Read Only Memory) (not shown). (Central Processing Unit) 11, DC input / output terminal 17 for inputting and outputting DC power, built-in storage battery 18 that can be charged by DC power, and DC power from the built-in storage battery 18 are converted into AC power. Inverter 21 and an AC output terminal 22 for outputting the AC power converted by the inverter 21. Further, a charge control circuit 12, which will be described later, a first switch circuit 14 provided in series with the charge control circuit 12 on the path of the power supply line between the DC input / output terminal 17 and the built-in storage battery 18, and a charge control circuit 12 and the first switch circuit 14, the second switch circuit 15 provided to electrically connect the DC input / output terminal 17 and the built-in storage battery 18, and the internal circuit when the DC input / output terminal 17 is abnormal And a protection circuit 20 for protection. Further, the voltage detector 19a for detecting the voltage of the DC input / output terminal 17, the voltage detector 19b for detecting the voltage of the internal storage battery 18, and the voltages of the voltage detectors 19a and 19b are detected and monitored. And a voltage monitoring unit 13. The processing performed by the voltage monitoring unit 13 may be performed by the CPU 11.

  The DC input / output terminal 17 can be connected to a DC power source such as a car cigarette socket or a solar cell, and a load using DC power as a power source.

  The CPU 11 determines whether the charging mode or the discharging mode based on the signal from the voltage monitoring unit 13. This determination will be described later in detail.

  In this embodiment, the case where the first switch circuit 14 is turned on and the second switch circuit is turned off is called a discharge mode. The case where the first switch circuit 14 is turned off and the second switch circuit is turned on is called a discharge mode.

  Therefore, in the charging mode, the DC input / output terminal 17 and the internal storage battery 18 are connected via the protection circuit 20 and the charging control circuit 12. On the other hand, in the discharge mode, the DC input / output terminal 17 and the built-in storage battery 18 are connected via the protection circuit 20 not via the charge control circuit 12.

  The protection circuit 20 is a circuit that passes in both the charge mode and the discharge mode. The DC input / output terminal 17 has a function of protecting the internal circuit when an abnormality such as a short circuit, overload, or overvoltage occurs.

  As described above, the charging control circuit 12 is a circuit through which DC power passes during the charging mode. The charge control circuit 12 has a function of controlling the voltage and current of DC power and maintaining an appropriate charge state for the internal storage battery 18. For example, when an input voltage to the internal storage battery 18 is detected and the voltage value exceeds a predetermined value, control is performed to cut off the current. Such a predetermined value is set in advance so as to be suitable for charging the internal storage battery 18. Thereby, overcharging can be prevented and the built-in storage battery 18 can be stably charged.

  The voltage monitoring unit 13 receives signals from the voltage detector 19a and the voltage detector 19b, and monitors the voltage Va at the DC input / output terminal 17 and the voltage Vb at the built-in storage battery 18.

  In this embodiment, the normal discharge mode is assumed. Therefore, when the voltage monitoring unit 13 detects that the voltage Va at the DC input / output terminal 17 is equal to or lower than the voltage Vb of the internal storage battery 18, the discharge mode is always set.

  On the other hand, when the voltage monitoring unit 13 detects that the voltage Va of the DC input / output terminal 17 detected by the voltage detector 19a is higher than the voltage Vb of the internal storage battery 18 detected by the voltage detector 19b, It is determined whether or not the voltage Va is higher than a predetermined voltage Vb0. The predetermined voltage Vb0 is determined in advance from a lower limit value for charging the internal storage battery 18 in consideration of a certain margin.

  When the voltage monitoring unit 13 detects that the voltage Va at the DC input / output terminal 17 is higher than the predetermined voltage Vb0, the voltage monitoring unit 13 transmits a High signal to the CPU 11. The High signal indicates that the charging mode is set.

  On the other hand, if the voltage Va at the DC input / output terminal 17 is not higher than the predetermined voltage Vb0, the voltage monitoring unit 13 transmits a Low signal to the CPU 11.

  Thus, in the present embodiment, the charging mode is not simply set when the voltage Va of the DC input / output terminal 17 is higher than the voltage Vb of the built-in storage battery 18, and the charging mode is detected after the input of a chargeable voltage is detected. And Thereby, the built-in storage battery 18 can be charged reliably.

  2 and 3 are diagrams for explaining the operation of the portable power supply device. FIG. 2 shows the operation in the charging mode, and FIG. 3 shows the operation in the discharging mode.

  Referring to FIG. 2, as described above, when a high signal is transmitted by voltage monitoring unit 13, first switch circuit 14 is turned on (conductive state) by CPU 11, and second switch circuit 15 is turned off (non-conductive). State). As a result, in the portable power supply device of the present embodiment, the DC power input from the DC input / output terminal 17 flows as shown by the dotted arrow in the figure. That is, the DC power input from the DC input / output terminal 17 is supplied to the built-in storage battery 18 via the protection circuit 20, the first switch circuit 14, and the charge control circuit 12.

  On the other hand, referring to FIG. 3, when the Low signal is transmitted from voltage monitoring unit 13, first switch circuit 14 is turned off (non-conducting state) and second switch circuit 15 is turned on (conducting state) by CPU 11. Be controlled. Thereby, in the portable power supply device of the present embodiment, the DC power output from the built-in storage battery 18 has a flow as indicated by the dotted arrow in the figure. That is, the DC power output from the internal storage battery 18 is supplied to the DC input / output terminal 17 via the second switch circuit 15 and the protection circuit 20.

  The first switch circuit 14 and the second switch circuit 15 perform switching between a route through the charge control circuit 12 and a route through the charge control circuit 12 in power supply between the DC input / output terminal 17 and the internal storage battery 18. It is provided for this purpose. Therefore, the present invention is not limited to this as long as the power supply path can be switched.

  Next, charging control processing in the portable power supply device of the present embodiment will be described using the flowchart shown in FIG. As described above, since the portable power supply according to the present embodiment is normally in the discharge mode, the first switch circuit 14 is initially in a non-conductive state and the second switch circuit is in a conductive state. .

  First, the CPU 11 determines whether or not there is an interrupt process (step S1). The interrupt process is performed, for example, when a power switch is turned on, when a change in the voltage of the DC input / output terminal 17 is detected, and at regular intervals (for example, 30 seconds). The CPU 11 does not start the charge control process until such an interrupt process is detected.

  When the CPU 11 detects that the interrupt process has been performed (YES in step S1), the CPU 11 causes the voltage monitoring unit 13 to start detecting the voltage (step S2). The voltage detection process started here is executed by a voltage detection program stored in a ROM (not shown) built in the CPU 11. According to this voltage detection program, the voltage monitoring unit 13 detects the voltage Va of the DC input / output terminal 17 detected by the voltage detector 19a and the voltage Vb of the internal storage battery 18 detected by the voltage detector 19b.

  Next, the voltage monitoring unit 13 determines whether or not the voltage Va at the DC input / output terminal 17 is higher than the voltage Vb of the internal storage battery 18 (step S3). If voltage Va at DC input / output terminal 17 is equal to or lower than voltage Vb of internal storage battery 18 (NO in step S3), the process returns to step S1. On the other hand, when voltage monitoring unit 13 determines that voltage Va at DC input / output terminal 17 is higher than voltage Vb of internal storage battery 18 (YES in step S3), the process proceeds to step S4.

  In step S4, the voltage monitoring unit 13 further determines whether or not the voltage Va at the DC input / output terminal 17 is higher than the predetermined voltage Vb0 (step S4).

  When the voltage monitoring unit 13 determines that the voltage Va at the DC input / output terminal 17 is higher than the predetermined voltage Vb0 (YES in step S4), a high signal is transmitted to the CPU 11 (step S5). ). On the other hand, when it is determined that the voltage Va at the DC input / output terminal 17 is equal to or lower than the predetermined voltage Vb0 (NO in step S4), a Low signal is transmitted to the CPU 11 (step S9).

  When the CPU 11 receives the High signal transmitted from the voltage monitoring unit 13 in step S5, the CPU 11 performs the process of step S6.

  In step S <b> 6, the CPU 11 transmits a signal for making the circuit conductive (ON signal) to the first switch circuit 14, and at the same time, a signal for making the circuit non-conductive to the second switch circuit 15 (OFF signal). ).

  By the process in step S6, the portable power supply device in the present embodiment is in the charging mode (step S7). That is, the internal storage battery 18 is connected to the DC input / output terminal 17 via the charge control circuit 12 and the protection circuit 20.

  In this way, the charging process for the internal storage battery 18 is performed (step S8). In step S8, when the CPU 11 detects that the charging process has ended, the CPU 11 switches to the discharge mode and ends this process.

  On the other hand, when the CPU 11 receives the Low signal transmitted from the voltage monitoring unit 13 in step S9, the CPU 11 performs the process of step S10.

  In step S <b> 10, the CPU 11 transmits a signal for turning off the circuit (OFF signal) to the first switch circuit 14, and at the same time a signal for turning on the circuit to the second switch circuit 15 (ON signal). ).

  By the process in step S10, the portable power supply device in the present embodiment is in the discharge mode (step S11). That is, the internal storage battery 18 is connected to the DC input / output terminal 17 via the protection circuit 20 without passing through the charge control circuit 12. In the present embodiment, since it is the normal discharge mode, the processes in steps S9 to S11 are processes for confirming that the charging mode is not set. Therefore, if the determination in step S4 is NO, the process may return to step S1.

  As described above, in the portable power supply device of the present embodiment, the DC input / output terminal 17 and the built-in storage battery 18 pass through the charging control circuit 12 in the charging mode. Thereby, when the voltage value detected in the charge control circuit 12 exceeds a predetermined value, the current is controlled to be cut off. Therefore, it is possible to prevent overcharging and always perform appropriate and stable charging of the internal storage battery 18.

  As shown in the flowchart of FIG. 4, both the process of step S3 and the process of step S4 are performed, but the process of step S3 may be omitted. In this case, in step S2, the voltage Va of the DC input / output terminal 17 is acquired from the voltage detector 19a. In step S4, it is determined whether or not the voltage Va is higher than a predetermined voltage Vb0. Based on this determination, the charging mode is set when the voltage Va at the DC input / output terminal 17 is higher than the predetermined voltage Vb0, and the discharging mode is set when the voltage Va at the DC input / output terminal 17 is equal to or lower than the predetermined voltage Vb0. Thus, by omitting the process in step S3, it is possible to more easily determine whether to set the discharge mode or the charge mode. Even in such a case, since the determination is made using the predetermined voltage Vb0, the charging mode can be set only when the input voltage is sufficient.

  Further, the process of step S4 may be omitted. In this case, if the voltage monitoring unit 13 determines in step S3 that the voltage Va at the DC input / output terminal 17 is higher than the voltage Vb of the built-in storage battery 18, a high signal is transmitted to the CPU 11 (step S5). Thereafter, steps S6 to S8 are performed. Thereby, control can be made easier.

  In the present embodiment, the normal discharge mode is described, but this need not be the case. In this case, for example, both the first switch circuit 14 and the second switch circuit 15 may be kept in a non-conductive state until there is an interrupt process shown in step S1 of FIG. In this case, when it is determined NO in step S3 described above, the process proceeds to step S9. By doing so, even when the voltage Va at the DC input / output terminal 17 is not higher than the internal storage battery 18Vb, the discharge mode can be set. The interrupt process in this case is, for example, when the power SW is turned on, and these processes are repeated until the power SW is turned off. The conduction / non-conduction control of the first switch circuit 14 and the second switch circuit 15 is not performed until the mode is changed. Thereby, the effect similar to the above-mentioned embodiment can be acquired.

  The portable power supply device according to the present embodiment can input and output DC power at DC input / output terminal 17. For this reason, it is possible to connect a DC power source and a load using DC power as a power source at a common terminal. Thereby, a user's usability can be improved. Further, by reducing the number of terminals in this way, the portable power supply device can be reduced in size.

  Further, charging and discharging are automatically performed in order to detect the voltages of the DC input / output terminal 17 and the built-in storage battery 18 and control the conduction / non-conduction state of the first switch circuit 14 and the second switch circuit 15. Is possible. Therefore, even if charging and discharging are performed at the DC input / output terminal 17, the charging control circuit 12 is automatically connected in the charging mode. Therefore, the built-in storage battery 18 can always be appropriately and stably charged.

  Also, stable AC power can be output from the internal storage battery 18 appropriately charged in this way via the inverter 21 and the AC output terminal 22.

  In the embodiment of the present invention, the portable power supply device has been described. However, the present invention is not limited to this as long as the device has a built-in storage battery and an output terminal for DC power.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a block diagram of the portable power supply device in an embodiment of the present invention. It is a figure which shows operation | movement of the portable power supply device at the time of charge mode. It is a figure which shows operation | movement of the portable power supply device at the time of discharge mode. It is a flowchart which shows the charge control process in the portable power supply device of embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 CPU, 12 Charge control circuit, 13 Voltage monitoring part, 14 1st switch circuit, 15 2nd switch circuit, 17 DC input / output terminal, 18 Built-in storage battery, 19a, 19b Voltage detector, 20 Protection circuit, 21 Inverter, 22 AC output terminal.

Claims (8)

A first terminal for inputting DC power from a DC power source and outputting DC power to a load;
A storage battery that can be charged by DC power from the first terminal;
A charge control circuit for controlling the input of DC power to the storage battery so that the input voltage to the storage battery is a predetermined value or less;
A switching means for switching and connecting the first path via the charge control circuit and the second path not via the charge control circuit between the first terminal and the storage battery;
First detecting means for detecting the voltage of the first terminal;
A portable power supply device comprising: control means for controlling the switching means based on the voltage of the first terminal detected by the first detection means. The switching means is
A first switch means provided in series with the charge control circuit on a path of power supply between the first terminal and the storage battery;
A second switch means provided for electrically connecting the first terminal and the storage battery, bypassing the charge control circuit and the first switch means;
The portable power supply device according to claim 1, wherein the control means controls conduction / non-conduction of the first switch means and the second switch means.   When the control means determines that the voltage at the first terminal is higher than a predetermined value, the control means sets the first switch means to a conductive state, the second switch means to a non-conductive state, and sets the voltage at the first terminal. 3. The portable power supply device according to claim 2, wherein when it is determined that the first switch means is not more than the predetermined value, the first switch means is turned off and the second switch means is turned on. A second detecting means for detecting a voltage of the storage battery;
When the control unit determines that the voltage of the storage battery detected by the second detection unit is equal to or higher than the voltage of the first terminal detected by the first detection unit, the control unit turns off the first switch unit. 3. The portable power supply device according to claim 2, wherein the second switch means is in a conductive state.   When the control means determines that the voltage of the first terminal detected by the first detection means is higher than the voltage of the storage battery detected by the second detection means, the first switch means The portable power supply device according to claim 4, wherein the second switch means is in a non-conductive state. An inverter unit for converting the DC power from the storage battery into AC power;
The portable power supply device according to claim 1, further comprising a second terminal provided to output the AC power converted by the inverter unit. Input of DC power from a DC power source and output of DC power to a load, a first terminal, a storage battery that can be charged by DC power from the first terminal, and input to the storage battery A charge control circuit for controlling the input of direct-current power to the storage battery, and the charge control on a path of a power supply line between the first terminal and the storage battery so that the voltage is equal to or less than a predetermined value; A first switch circuit provided in series with the circuit, and a second switch provided to electrically connect the first terminal and the storage battery, bypassing the charge control circuit and the first switch circuit A charge control method for a portable power supply device comprising a circuit,
A detecting step of detecting a voltage of the first terminal;
A determination step of determining whether or not the voltage of the first terminal detected by the detection step is higher than a predetermined value;
When the determination step determines that the voltage at the first terminal is higher than the predetermined value, the first switch circuit is turned on and the second switch circuit is turned off;
When the determination step determines that the voltage at the first terminal is equal to or lower than the predetermined value, the first switch circuit is turned off and the second switch circuit is turned on. Charge control method. Input of DC power from a DC power source and output of DC power to a load, a first terminal, a storage battery that can be charged by DC power from the first terminal, and input to the storage battery A charge control circuit for controlling the input of direct-current power to the storage battery, and the charge control on a path of a power supply line between the first terminal and the storage battery so that the voltage is equal to or less than a predetermined value; A first switch circuit provided in series with the circuit, and a second switch provided to electrically connect the first terminal and the storage battery, bypassing the charge control circuit and the first switch circuit A charge control method for a portable power supply device comprising a circuit,
A first detection step of detecting a voltage of the first terminal;
A second detection step of detecting a voltage of the storage battery;
A determination step of determining whether a voltage of the first terminal detected by the first detection step is higher than a voltage of the storage battery detected by the second detection step;
A step of setting the first switch circuit in a conductive state and the second switch circuit in a non-conductive state when the determination step determines that the voltage of the first terminal is higher than the voltage of the storage battery; ,
And a step of setting the first switch circuit in a non-conductive state and the second switch circuit in a conductive state when the determination step determines that the voltage of the first terminal is equal to or lower than the voltage of the storage battery. , Charging control method.

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