JP2011035981A - Solar system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar system which can charge a secondary battery in an apparatus by using a solar battery as a power supply. <P>SOLUTION: The solar system 1 is constituted of a solar battery charge device 100 which uses the solar battery 120 as the power supply and has a charge control circuit 200, and a radio 300 which uses a chargeable battery pack 3 as the power supply and has a power supply circuit 314 and a radio circuit 30. The charge control circuit 200 controls a switching power supply circuit 8 according to a preset input voltage, a charge voltage and a charge current, and outputs a charge power from the battery pack 3 via a connecting part 110. A microcomputer 11 controls a charge on/off circuit 13 according to a battery type by detecting information on the battery pack 3 via the connecting part 110. Since the radio 300 is not equipped with a charge circuit, it can be reduced in weight, cost and noise, and thus can be charged by the solar battery charge device 100 irrespective of the battery type. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a solar system having a solar cell, a solar cell unit provided with a charger that charges a secondary battery using the solar cell as a power source, and a device driven by the secondary battery that can be charged by the charger. About.

  Conventionally, a charging device for charging a nickel-cadmium battery or a lithium-ion battery is charged by being supplied from a commercial power source. However, when a device such as a radio is used in a place where commercial power is not supplied such as outdoors, the user must prepare a number of spare batteries. Therefore, there is a demand for a charging device that can be charged from another power source other than the commercial power source. For example, there has been proposed a charging device that includes a plurality of converters as voltage conversion means and can charge a battery pack from at least two types of power sources by selecting a converter that is driven according to the power source to be used (for example, a patent) Reference 1).

Japanese Patent Laying-Open No. 2005-245145 (page 3-5, FIG. 1)

  Various power sources are conceivable as power sources other than the commercial power source. For example, consider a solar cell that is attracting attention because it is environmentally friendly and clean. Currently, it is difficult to say that solar cells still have excellent solar-to-electrical energy conversion efficiency, and they are expensive in terms of price if appropriate power supply is required. For this reason, a product that proposes a charging system using a solar cell as a power source is expensive. Therefore, in order to match the needs of the market, it is preferable in terms of product configuration that the system for charging the secondary battery using the solar battery as a power source is sold separately (optional).

  Also, since the output power of the solar battery varies greatly depending on the amount of sunlight, when charging the battery pack at the best time using the solar battery as a power source, the best and stable charge according to the output power of the solar battery is performed. Therefore, a power conversion circuit is required. Furthermore, when the battery pack to be charged is a lithium battery, the maximum charging voltage must not exceed the overvoltage of the lithium battery to be charged, so a constant voltage charge control circuit is required.

  In such a charging system using a solar cell as a power source, the power conversion circuit and the charging control circuit are provided on the side of a device such as a radio that is used in a state where the battery to be charged is mounted, and only the solar cell is used as a radio or the like. A configuration in which the battery pack to be charged is charged by connecting to a device is conceivable.

  However, if the solar cell as a power source is configured separately and the charging control circuit etc. is arranged inside a device such as a radio, a user who does not need a system for charging a secondary battery with a separately sold solar cell This eliminates the need for a charge control circuit disposed inside a device such as a radio, and it imposes a price burden on the user for the charge control circuit or results in a wasteful price loss for the manufacturer.

  In addition, when deploying secondary battery charging systems powered by solar cells in various products, a charging control circuit is required for all devices that support solar battery charging systems, which greatly hinders the deployment of compatible devices. End up.

  Therefore, an object of the present invention is to propose a solar cell charging system that has a relatively simple configuration and is useless in a device that operates with a secondary battery.

  In order to achieve the above object, the invention described in claim 1 includes a solar battery unit having a solar battery and a charger that charges the battery using electric power output from the solar battery as a power source, and a plurality of different output voltages. A solar system having a device that can use any type of battery as a power source and removably connect any of a plurality of types of batteries, wherein the device has charging power input means for inputting power for charging the battery; An information output means for outputting information related to the battery, and the solar cell unit includes an external connection means connected to the charging power input means and the information output means provided in the device, and a charger. Includes an information detection unit that reads information on a battery connected to the device via an information output unit and an external connection unit, and a charge control unit that performs charge control based on the information. It is characterized in.

  According to such a configuration, battery information is output to the solar cell unit from the information output unit of the device, the information detection unit of the solar cell unit detects the information, and the charge control unit performs charging according to the detected information. To control.

  According to the solar system of the present invention, the solar cell unit can detect information related to the secondary battery provided in the device. Moreover, since charging is controlled according to the detected information, charging control according to the type of battery, connection state, and the like provided in the device is possible. Therefore, it is possible to provide an excellent effect that a solar system without waste can be provided with a simple configuration.

1 is a block diagram showing a radio according to an embodiment of the present invention. The block diagram which shows an example of the conventional radio. The circuit diagram which shows the solar system by one embodiment of this invention. The flowchart which shows the charging method by one embodiment of this invention. The circuit diagram which shows the solar system by the modification of this invention.

  A solar system according to an embodiment of the present invention will be described with reference to FIGS. The solar system according to the present embodiment includes a solar battery unit that charges a secondary battery using a solar battery as a power source, and a device that includes the secondary battery that is charged by the solar battery unit. In this embodiment, a radio will be described as an example of the device.

  As shown in FIG. 1, a radio 300 according to an embodiment of the present invention includes a battery pack 3, a power supply circuit 314, a radio circuit 30, and a speaker 31, and an AC adapter input for supplying power from a commercial power supply. The terminal 313 and the connection part 310 which can be connected with the solar cell charging device mentioned later are included. The radio 300 operates using power input through the battery pack 3 or the AC adapter input terminal 313 as a power source. The connection part 310 is comprised by the connection terminals 331-337, and is comprised so that the battery pack 3 may be charged by connecting with the external solar cell charging device mentioned later via the connection part 310. FIG.

  The battery pack 3 includes a battery set 3a, a battery type discrimination resistor 3b, and a thermistor 3c, and is detachably disposed on the radio 300. In the present embodiment, the battery set 3a is configured by connecting four secondary battery cells such as a nickel cadmium battery (hereinafter referred to as a nickel cadmium battery) or a lithium ion battery in series, and includes a plus terminal 311 and a minus terminal 312. Connected between. Further, the plus side of the battery set 3a is connected to the terminal 337, and the minus side is connected to the terminal 331, so that charging power is supplied from an external charging device. The battery type identification resistor 3b is connected between the minus side of the battery set 3a and the connection terminal 335, and has a resistance value corresponding to the type and number of battery cells of the battery set 3a. The thermistor 3c is connected between the negative side of the battery set 3a and the connection terminal 333 in the vicinity of the battery set 3a, and is a temperature sensitive element for detecting the battery temperature.

  The power supply circuit 314 is connected to the battery pack 3 via the positive electrode terminal 311 and the negative electrode terminal 312, and is a circuit that converts the output voltage of the battery pack 3 into a voltage suitable for driving the radio circuit 30. For example, when the battery set 3a connected in series as shown in FIG. 1 is a lithium ion battery, the output voltage is 3.6 (V) × 4 (number of cells) = 14.4 (V). Even if the output voltage of the battery pack 3 is different, such as 10.8 V for 3 series and 7.2 V for 2 series, it is converted to a voltage suitable for driving the radio circuit 30. Moreover, the battery pack which has another kind of battery cells, such as a nickel-cadmium battery, may be sufficient. That is, the radio 300 can use a plurality of types of batteries with different output voltages as a power source.

  The radio circuit 30 is a known radio circuit that operates by power supply from the power supply circuit 314. The radio circuit 30 includes an antenna 303, an AM / FM tuner 305, a selector 307, a preamplifier 309, and a power amplifier 325. The radio circuit 30 detects the radio wave received by the antenna 303 with the AM / FM tuner 305, selects with the selector 307, adjusts with the preamplifier 309, amplifies with the power amplifier 325, and responds to the instruction on the operation panel 327. The signal is output to the speaker 31, and the speaker 31 converts the input signal into sound.

  In radio 300, connection part 310 for connecting to an external charging device is configured with terminals 331 to 337 as described above. The terminal 331 is connected to the negative side of the battery set 3a and is a terminal to which a reference potential is input. The terminal 333 is a temperature detection terminal that is connected to the thermistor 3c and outputs a signal corresponding to the temperature of the battery set 3a. The terminal 335 is a battery pack identification terminal that is connected to the battery type determination resistor 3b and outputs a signal corresponding to the type and output voltage of the battery cell. The terminal 337 is connected to the positive side of the battery set 3a and is a terminal to which charging power for charging the battery set 3a is input.

  With the above configuration, the radio 300 includes the battery pack 3 and is driven by the battery pack 3. At this time, the output voltage of the battery pack 3 is converted into a voltage suitable for driving the radio circuit 30 via the power supply circuit 314 and output. Further, the battery pack 3 of the radio 300 is charged by being connected to an external charging device via the connection unit 310. At the time of charging, the radio 300 outputs information about the battery pack 3 via the connection unit 310, but does not have a circuit for charging. The radio 300 has a configuration in which a charging circuit using an AC adapter as a power source is not mounted in order to eliminate an efficient switching power source or the like inside the radio.

  For comparison, an example of a conventional radio 200 is shown in FIG. The same components as those of the radio 300 according to the present embodiment are denoted by the same reference numerals and description thereof is omitted. As shown in FIG. 2, the radio 200 includes a battery pack 210, a power supply circuit 314, a radio circuit 30, and a speaker 31, and has an AC adapter input terminal 313 for supplying power from a commercial power supply.

  Similar to the battery pack 3, the battery pack 210 includes a battery set 3 a having four battery cells, and is connected to a power supply circuit 314 through a positive electrode terminal 311 and a negative electrode terminal 312.

  The radio 200 is driven by a commercial power source input from the AC adapter input unit 313 or the battery pack 210. Similar to the radio 300, the output from the battery pack 210 is converted into an appropriate voltage for driving the radio circuit 30 by the power supply circuit 314, so that a plurality of types of power supplies can be used. However, since the radio 200 does not have a terminal for connecting to an external charging device, the battery pack 210 is removed when charging. In addition, since charging is performed by removing the battery pack 210, the thermistor, the battery type discrimination resistor, and a terminal for outputting a signal based thereon are not provided, and information regarding the battery cannot be output to the outside. It has a configuration.

  Next, the solar battery charging device 100 that is connected to the radio 300 as described above through the connection unit 310 and charges the battery pack 3, and the configuration of the solar system 1 that includes the solar battery charging device 100 and the radio 300. explain.

  As shown in FIG. 3, the solar cell charging device 100 is a solar cell unit that uses a solar cell as a power source, and outputs the output from the solar cell 120, the charge control circuit 200, and the charge control circuit 200 to the external connection unit 110. For example, it is housed in an integral panel. The output power of the solar battery 120 is input to the charge control circuit 200, and the charge control circuit 200 outputs a predetermined power capable of charging the battery to be charged to the connection unit 110 using the output of the solar battery 120 as a power source. The charging control circuit 200 is connected to the radio 300 via the connection unit 110 and the connection unit 310, and charges the battery pack 3 based on information about the battery output from the built-in battery pack 3.

  The solar cell 120 is a power source that generates power when light enters. The solar battery 120 may be configured to be removable from the solar battery charger 100. The charging control circuit 200 includes a smoothing capacitor 6 and a switching power supply circuit 8, generates charging power for charging the secondary battery, and outputs the generated charging power to the connection unit 110. The charging control circuit 200 includes an input voltage feedback circuit 7, a charging voltage feedback circuit 9, a charging current feedback circuit 10, a microcomputer 11, an auxiliary power supply 2, a battery type determination circuit 4, a battery temperature detection circuit 5, and a battery voltage detection circuit 12. The charging on / off circuit 13 is provided to control charging power.

  Smoothing capacitor 6 smoothes the output of solar cell 120. The switching power supply circuit 8 is a circuit for controlling a charging voltage and a charging current, and includes a DC / DC converter 8a, a P-channel FET 8b, a rectifier diode 8c, a coil 8d, and a smoothing capacitor 8e. In this embodiment, the voltage of the solar cell is stepped down to generate a charging voltage. The DC / DC converter 8a is a step-down circuit connected to the positive and negative outputs of the smoothing capacitor 6 and the gate of the FET 8b. The DC / DC converter 8a receives a feedback signal output from a charging voltage feedback circuit 9 and a charging current feedback circuit 10 to be described later, and controls the switching timing of the FET 8b in accordance with the signal to charge the DC / DC converter 8a. Control current and charge voltage. The source of the FET 8b is connected to the positive side of the solar cell 120. The rectifier diode 8c is connected between the drain of the FET 8a and the negative side of the solar cell 120. The input side of the coil 8d is connected to the drain of the FET 8b, and the smoothing capacitor 8e is connected between the output side of the coil 8d and the negative side of the solar cell 120, and smoothes the output of the DC / DC converter 8a.

  The input voltage feedback circuit 7 includes resistors 7a, 7b, 7c, 7d and an operational amplifier 7e. The resistors 7a and 7b are connected in series to each other and divide the output voltage of the solar cell 120 as an input, and the divided value is input to the non-inverting input terminal of the operational amplifier 7e. The resistors 7c and 7d are connected in series with each other, divide the value of the voltage Vcc, and input it to the inverting input portion of the operational amplifier 7e as an input voltage setting value for keeping the input voltage at a certain predetermined value. The output voltage value of the solar cell 120 divided by the resistors 7a and 7b is controlled based on the output signal of the operational amplifier 7e so that the input voltage setting value obtained by dividing the voltage Vcc by the resistors 7c and 7d is obtained. The value set as the input voltage setting value is set to a value that allows the power to be taken out from the solar cell 120 substantially close to the maximum power.

  The charging voltage feedback circuit 9 includes resistors 9a, 9b, 9c and 9d, an operational amplifier 9e, and a diode 9f. The resistors 9a and 9b divide the output voltage of the switching power supply circuit 8, that is, the charging voltage, and the divided value is input to the non-inverting input terminal of the operational amplifier 9e. The resistors 9c and 9d divide the value of the voltage Vcc, and the divided voltage is input to the inverting input terminal of the operational amplifier 9e as a charging voltage setting value for keeping the charging voltage at a predetermined value. A signal corresponding to the difference between the charging voltage divided by the resistors 9a and 9b and the charging voltage set value obtained by dividing the voltage Vcc by the resistors 9c and 9d is output from the operational amplifier 9e, and the DC / DC converter is based on the signal. The charging voltage is controlled by 8a switching the switching FET 8b. Here, since the diode 9f is connected in series to the output side of the operational amplifier 9e, the charging voltage set value is actually a limit voltage value for preventing the battery voltage from rising above this set value. Thus, the DC / DC converter 8a performs switching of the FET 8b so as to increase the voltage when the voltage falls below the charging voltage set value, and conversely, the FET 8b reduces the voltage when the voltage rises above the set value. A predetermined voltage is maintained by switching.

  The charging current feedback circuit 10 includes a shunt resistor 10a, resistors 10b, 10c, 10d, 10e, and 10f, operational amplifiers 10g and 10h, and a diode 10i. When a current flows through the shunt resistor 10a, a negative potential of current x shunt resistor x (-1) is input to the non-inverting input terminal of the operational amplifier 10g. The operational amplifier 10g and the resistors 10b, 10c, and 10d constitute an inverting amplifier circuit, and a value that is 10d / 10c times the negative potential proportional to the charging current input to the non-inverting input terminal of the operational amplifier 10g is obtained from the output. Is output. The output value is input to the non-inverting input terminal of the operational amplifier 10h. On the other hand, the output of the operational amplifier 7e, which is a feedback signal from the input voltage feedback circuit 7, is input to the inverting input terminal of the operational amplifier 10h. The operational amplifier 10h outputs a current control signal corresponding to the charging current flowing through the shunt resistor 10a and the output of the input voltage feedback circuit 7, and controls the switching of the FET 8b by the DC / DC converter 8a to control the charging current. At this time, since the diode 10i is connected in series to the output side of the operational amplifier 10h, the current control signal is a signal for actually preventing the charging current from rising above a predetermined value.

  Here, consider a case where the input voltage (the voltage of the solar battery 120) is higher than the input voltage setting set in the input voltage feedback circuit 7. In the present embodiment, the charging voltage and the charging current are controlled in the switching power supply circuit 8 based on the feedback output from the operational amplifiers 9e and 10h. That is, switching control is performed in the switching power supply circuit 8 so that the potentials of the non-inverting input portion and the inverting input portion of the operational amplifiers 9e and 10h become the same potential (imaginary short). As the input voltage rises, the input voltage feedback circuit 7 cannot balance the input section of the operational amplifier 7e. Further, since the output of the operational amplifier 7e is input to the input portion of the operational amplifier 10h of the charging current feedback circuit 10, the input portion of the operational amplifier 10h cannot be balanced. Then, the switching power supply circuit 8 performs switching so that the input parts of the operational amplifiers 7e and 10h are balanced based on the feedback signal from the operational amplifier 10h. By performing this switching, the charging current is increased to such a value that the input voltage decreases to the input voltage setting. Conversely, when the input voltage (solar cell voltage) is lower than the input voltage setting set in the input voltage feedback circuit 7, the switching power supply circuit 8 increases the charging current to the input voltage setting. Reduce to value. That is, when the irradiation amount increases and the solar cell voltage increases, the charging current is increased. Conversely, when the irradiation amount decreases and the solar cell voltage decreases, switching is performed to decrease the charging current. The power supply circuit 8 controls the battery voltage of the solar battery to a predetermined value by performing control.

  The microcomputer 11 includes a CPU 11a, output ports 11b, 11c, 11e, and A / D ports 11e, 11f, and controls the operation of the charge control circuit 200.

  The battery voltage detection circuit 12 includes resistors 12a and 12b. The battery voltage is divided by the resistors 12a and 12b and input to the A / D port 11f of the microcomputer 11.

  The charge on / off circuit 13 includes resistors 13a, 13b, 13c, 13d, a Pch FET 13e, and an Nch FET 1f. The source of the FET 13 e is connected to the output side of the switching power supply circuit 8, and the drain is connected to the terminal 119. The gate of the FET 13e is connected to the drain of the FET 13f through the resistor 13d. The resistor 13c is connected between the source and gate of the FET 13e, and the resistor 13b is connected between the gate and source of the FET 13f. When charging, the FET 13f is turned on by outputting a high signal from the output port 11b connected to the resistor 13a of the microcomputer 11. When the FET 13f is turned on, the Pch FET 13e is turned on, the charge control circuit 200 and the battery set 3a are connected, a charging current flows, and charging is performed. Conversely, when charging is terminated, the FET 13f is turned off by outputting a low signal from the output port connected to the resistor 13a of the microcomputer 11. When the FET 13f is turned off, the Pch FET 13e is turned off, and the charge control circuit 200 and the battery set 3a are cut off, whereby the charging is terminated.

  The battery type discriminating circuit 4 is a battery type discriminating means for discriminating the type of the battery pack 4a, and includes a resistor 4a. The battery type is determined by inputting a value obtained by dividing the voltage Vcc by the resistor 4a and the battery type determining resistor 3b set in the battery pack 3 to an A / D port 11e of the microcomputer 11 described later. The battery type here means, for example, a difference in the type of the battery itself such as a lithium ion battery, a nickel hydride battery, or a nickel cadmium battery, or a difference in the number of cells in the lithium ion battery (for example, a difference such as 4 cells or 5 cells) or It is the difference between the connection states (series and parallel). The reason for determining the battery type is that the charge control method differs depending on the battery type, and accordingly, it is necessary to perform appropriate charging for each battery type.

  The battery temperature detection circuit 5 is a battery temperature detection means composed of resistors 5a and 5b. The battery temperature is a value obtained by dividing the voltage Vcc by the resistor 5a, the resistor 5b and the parallel resistance of the thermistor 3c, which is a temperature-sensitive element whose resistance value varies depending on the battery temperature in the battery pack 3, and the microcomputer 11 described later. Reading is performed by inputting to the A / D port 11e.

  The charging state display circuit 14 is a display circuit for informing the user of the presence or absence of charging, and includes resistors 14a, 14b, 14c, an LED 14d, and an FET 14e. During charging, by outputting a high signal from the output port 11c connected to the resistor 14b of the microcomputer 11, the FET 14e is turned on and the LED 14d is turned on. Conversely, when the battery is not charged, the FET 14e is turned off and the LED 14d is turned off by outputting a low signal from the output port 11c.

  The auxiliary power source 2 is a power source for the microcomputer 11 and operational amplifiers, and includes a DC / DC converter 2a, a Pch FET 2b, a rectifier diode 2c, a coil 2d, a smoothing capacitor 2e, and resistors 2f and 2g. The In this embodiment, the voltage of the solar cell is stepped down to generate a voltage Vcc that serves as a power source for the microcomputer 11 and the like. The DC / DC converter 2a steps down the output of the smoothing capacitor 6. The DC / DC converter 2a switches the FET 2b, which is a switching element, so that a value obtained by dividing the output voltage by the resistors 2f and 2g becomes a predetermined value set in the DC / DC converter 2a. The values of the resistors 2f and 2g may be set so that a value obtained when the desired voltage Vcc is divided by the resistors 2f and 2g becomes a predetermined voltage set in the DC / DC converter 2a.

  Next, the operation of the solar system according to the embodiment of the present invention will be described with reference to FIGS. First, when the solar battery 120 as an input power source is connected to the solar battery charger 100, the solar battery charger 100 enters an operating state using the solar battery 120 as a power source. Before the secondary battery is mounted, the LED 14d is turned off to notify the user that charging is not being performed (step 301). In order to turn off the LED 14d, the FET 14e is turned off by outputting a low signal from the output port 11C connected to the resistor 14b of the microcomputer 11. In step 302, it is determined whether or not the battery pack 3 is mounted on the charging device. The connection of the battery pack 3 may be determined by, for example, a change in the detection signal of the battery temperature detection circuit 4 input to the A / D port 11e of the microcomputer 11. Next, the battery type is determined based on the detection signal from the battery type detection circuit 4 (step 303). The battery type is set in accordance with the resistance value of the battery type discriminating element 3b in the battery pack 3. For example, the type of lithium ion battery, nickel hydrogen battery, nickel cadmium battery, 14.4V, 18V battery, etc. Or the number of battery cells in the battery pack 3 or the connection state.

  Here, a determination is made as to whether the battery is a lithium ion battery or not (step 304). In the case of a lithium ion battery (step 304: YES), charging is started in step 305. Charging is started by outputting a high signal from the output port 11b connected to the resistor 13a of the microcomputer 11 to turn on the FET 13f and FET 13e, and the switching power supply circuit 8 and the battery pack 3 are connected. When charging is started, the LED 14d in the charging state display circuit 14 is turned on to notify the user of the start of charging (step 306). To turn on the LED 14d, a high signal is output from the output port 11C connected to the resistor 14b of the microcomputer 11, and the FET 14e is turned on.

  At this time, in order to determine whether or not the battery is fully charged, it is detected whether the battery voltage is equal to or higher than a predetermined value (step 307). The microcomputer 11 detects the battery voltage based on a signal input from the battery voltage detection circuit 12 to the A / D port 11f. Step 307 is repeated as long as the predetermined value is not exceeded. The predetermined value of the battery voltage that is determined to be fully charged at this time is based on the battery type detected in step 303, for example, 4 cells × 4.2V = 16.8V, 5 cells if it is a lithium ion battery connected in series of 4 cells. In the case of a series-connected lithium ion battery, the voltage may be set to 4.2 V per cell such as 5 cells × 4.2 V = 21 V. If it is equal to or greater than the predetermined value, it is determined that the battery is fully charged, and charging is terminated (step 311). The charging is terminated by outputting a low signal from the output port 11b connected to the resistor 13a of the microcomputer 11 to turn off the FET 13f and the FET 13e and shut off the switching power supply circuit 8 and the battery pack 3.

  If NO in step 304, charging is started in step 308 and the LED 14d is turned on (step 309). At this time, for example, a nickel-cadmium battery, a nickel-metal hydride battery, or the like can be considered as the type of battery. As a method of determining full charge, the battery temperature detected by the battery temperature detection circuit 5 is equal to or higher than a predetermined temperature during charging. For example, a method may be used in which the charging is determined to be a full charge. In step 310, when the battery temperature becomes equal to or higher than a predetermined value, it is determined that the battery is fully charged, and the charging is terminated (step 311).

  When charging is terminated in step 311, the LED 14 b of the charging state display circuit 14 is turned off in order to notify the user that the charging is completed (step 312). To turn off the LED 14b, a low signal is output from the output port 11C connected to the resistor 14b of the microcomputer 11, and the FET 14e is turned off. Next, it is determined whether or not the battery pack 3 has been removed from the charging device (step 313).

  With the operation as described above, the solar system 1 according to the present embodiment is configured such that the radio 300 does not include any circuit relating to the charging of the battery pack 3, and the solar battery charging device 100 connected to the connection unit 310 is configured. The battery pack 3 attached to the radio 300 can be charged by the power supply and the charging control. In addition, since the charging circuit is not incorporated in the radio 300, it is possible to reduce the weight, the cost, and the noise.

  Furthermore, the solar battery charger 100 determines the battery type of the battery pack 3 built in the radio 300, detects full charge by a method according to the battery type, and stops charging. Therefore, even if the type of battery provided in the radio 300 is unknown, the battery pack 3 inside the radio 300 can be safely charged using the solar battery 120 as a power source. Therefore, the user can use the solar battery charger 100 without worrying about the battery type and output voltage of the battery pack 3.

  Next, a solar system 500 according to a modification of the present invention will be described with reference to FIG. Constituent elements common to the solar system 500 and the solar system 1 are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 5, the solar system 500 according to the present modification includes a radio 470 and a solar battery charger 400.

  The radio 470 includes a radio circuit 30, a power supply circuit 314, and a detachable battery pack 460. Moreover, it has the connection part 350 connected with the solar cell charging device 400. FIG. The connection unit 350 is obtained by adding a terminal 320 to which a signal from the protection circuit 3e is output to the configuration of the connection unit 310 according to the above embodiment. The battery pack 460 includes a protection circuit 3e and a current detection resistor 3d in addition to the configuration of the battery pack 3. In this example, the protection circuit 3e monitors the voltage of each battery cell of the battery set 3a connected in series, and outputs a charge stop signal via the output terminal 320 if any one of the battery cells becomes higher than a predetermined voltage value. To do. The protection circuit 3e outputs a charge stop signal via the output terminal 320 when the current detection resistor 3d detects a current larger than a predetermined current value.

  The solar battery charger 400 includes a solar battery 120, a charge control circuit 450, and an electric wire that outputs an output from the charge control circuit 450 to an external connection unit 150, and is configured to be housed in an integrated panel, for example. The connection unit 150 is obtained by adding a terminal 111 for transmitting a charge stop signal from the protection circuit 3e to the configuration of the connection unit 110 of the above embodiment. The terminal 111 is connected to the gate of the FET 13 f of the charge on / off circuit 13. When a charge stop signal is input to the terminal 111, the FET 13f and the FET 13e of the charge on / off circuit 13 are turned off, and the charging is stopped by disconnecting the connection between the switching power supply circuit 8 and the battery 460.

  As described above, according to the solar system 500 according to the present modification, when the battery 460 is overcharged, overcurrent, etc., the charge control circuit 450 detects the information, and charging can be controlled accordingly.

  As described above, according to the solar system 500 according to the modified example of the present invention, the radio 470 does not include any circuit related to the charging of the battery pack 460, and the solar battery charger 400 connected to the connection unit 350. The battery pack 460 attached to the radio 470 can be charged by the power supply and charging control. In addition, since the charging circuit is not incorporated in the radio 470, it is possible to reduce weight, cost, and noise.

  Furthermore, the solar battery charger 400 determines the battery type of the battery pack 460 built in the radio 470, detects full charge by a method according to the battery type, and stops charging. Further, the protection circuit 3 e detects an overcurrent and overcharge of the battery pack 460 and outputs it from the connection terminal 320. The solar battery charger 400 detects these and stops charging. Therefore, even if the type of battery provided inside radio 470 is unknown, battery pack 460 inside radio 470 can be safely charged using solar battery 120 as a power source. Therefore, the user can use the solar battery charger 100 without worrying about the battery type and output voltage of the battery pack 460.

  In the above-described embodiments and modifications, the solar battery chargers 100 and 400 correspond to the solar battery unit of the present invention, the radios 300 and 470 correspond to devices, and the terminals 331 and 337 serve as charging power input means. The terminals 329, 333, and 335 correspond to information output means, the connection units 110 and 150 correspond to external connection means, the microcomputer 11 corresponds to information detection means, and the charging on / off circuit 13 is charged. It corresponds to the control means.

  The solar system according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims. For example, the full charge detection method for determining that the battery is fully charged when the battery voltage or the battery temperature becomes higher than a predetermined value has been described. However, these full charge detection methods are merely examples, and are not limited thereto, and need to be appropriately determined. . The circuit configuration of the solar battery charger is not limited to the above configuration as long as the same operation and operation are performed. Further, the device is not limited to a radio, but can also be applied to a music player such as a CD, an image display device such as a television, and other electrical devices. The secondary battery is not limited to the above, but may be another battery type.

  The solar system of the present invention can be used for an electric device driven using a secondary battery.

DESCRIPTION OF SYMBOLS 1,500: Solar system 7: Input voltage control circuit 8: Switching power supply circuit 9: Charge voltage feedback circuit 10: Charge current feedback circuit 11: Microcomputer 13: Charge on / off circuit 100, 400 Solar battery charger 120: Solar battery 200, 450: Charge control circuit 300, 470: Radio 3, 460: Battery pack 3a: Battery set 3b: Battery type discrimination resistor 3c: Thermistor 111, 113, 115, 117, 119, 329, 331, 333, 335, 337: Terminal

Claims (1)

A solar cell unit having a solar cell and a charger that charges the battery using the power output from the solar cell as a power source, and a plurality of types of batteries that output different voltages can be used as a power source. A solar system having a device detachably connected to one of them,
The equipment is
Charging power input means for inputting power for charging the battery;
An information output means for outputting information on the battery,
The solar cell unit is
An external connection means connected to the charging power input means and the information output means provided in the device;
The charger is
Information detection means for reading information of the battery connected to the device via the information output means and the external connection means;
Charge control means for performing charge control based on the information;
A solar system characterized by comprising:

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