JP2013074661A - Charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the following problem: In a conventional charger, electric power in proportion to electric power supplied to a power supply for charge output is supplied to a power supply for charge control circuit, and power consumption of the power supply for charge output is low and when power consumption of the power supply for charge control circuit is large, electric power supplied from a primary power circuit lowers and electric power cannot be sufficiently supplied to the power supply for charge control circuit, thus causing impossible operation maintenance of the charger.SOLUTION: The charger, configured so that electric power can be supplied to each of a power supply for charge output that outputs a charge output from one transformer and a power supply for charge control circuit that supplies electric power to a charge control circuit, achieves low power consumption of the power supply for charge output and can output a voltage with the power supply for charge control circuit stable even when the power consumption of the power supply for charge control circuit is large, thereby to reduce power consumption during standby.

Description

  The present invention relates to a charging device configured to individually supply power to a power source for charging output that outputs a charging output from one transformer and a power source for charging control circuit that supplies power to the charging control circuit. The present invention relates to a charging device that reduces power consumption during standby when no pack is inserted.

  In recent years, interest in environmental issues such as global warming has increased. Under these circumstances, rechargeable batteries such as lithium-ion batteries that have been used as power sources for mobile devices such as mobile phones and laptop computers are vehicles, motorcycles, and cultivators that have traditionally been driven by engines from the standpoint of reducing CO2 emissions and saving energy. The drive source is changed to a motor, and a rechargeable battery is mounted as a power source for driving the motor.

  In this way, the device main body is tackled for environmental problems such as CO2 reduction by using a rechargeable battery. Furthermore, there is an increasing interest in chargers that charge rechargeable batteries, and efforts are also being made to reduce power consumption of chargers, such as higher efficiency and lower standby power.

  In addition, rechargeable batteries used for main devices are required to have high safety and long-time driving. In order to ensure high safety, the rechargeable battery pack incorporates a battery control circuit (Battery Management Unit, hereinafter referred to as BMU) having charge / discharge control of the rechargeable battery and various protection functions.

  During charging, the charging control circuit of the BMU and charger always monitors whether the rechargeable battery is in an unsafe state such as overdischarge, overvoltage, overcurrent, etc., and stops charging if an abnormality occurs, and the charger indicator lamp Warnings are added to increase safety during charging. At this time, the charger performs control by installing a microcomputer in the charge control circuit for communication with the BMU and switching of the display lamp.

  A charger equipped with a microcomputer supplies power to a charging output circuit that outputs charging current and charging voltage from a single transformer, and to a charge control circuit and display lamp including the microcomputer, in order to supply power to the microcomputer. In some cases, the power supply for the charge control circuit is composed of two power supplies.

  There are several methods for controlling the power supply configured as described above.

  Examples thereof include Patent Document 1 and Patent Document 2. The main contents of each are listed in the problem to be solved by the invention.

  Usually, in order to control the output of the power supply for charging output and the power supply for charging control circuit with high accuracy, a method of feeding back signals to the switching power supply circuit of the primary power supply circuit from both power supplies and controlling the two outputs, Since the charging output is controlled with high accuracy, the charging output power supply controls the charging output by feeding back a signal to the switching power supply circuit of the primary power supply circuit, but the charging control circuit power supply does not perform feedback control. .

  In the latter method, the charge control circuit power supply is supplied with power proportional to the power supplied to the charge output power supply, and this power is controlled to a desired voltage by the charge control power supply to the charge control circuit. Supply.

JP 2010-239788 A JP 2004-312892 A

  In the latter circuit configuration described above, that is, the charge output power supply controls the charge output by feeding back a signal to the switching power supply circuit of the primary side power supply circuit. Small and inexpensive circuit configuration is possible, but if the power consumption of the power supply for charging output is small and the output of the power supply for charging control circuit is large, the power supplied from the primary side power supply circuit will decrease, Sufficient power cannot be supplied to the power supply, and the operation of the charger cannot be maintained.

  For example, immediately after the battery pack is inserted, it is verified whether the rechargeable battery pack is normal, and when the charging output is not yet output or when the battery pack is hot and dangerous to charge, the temperature For example, when charging is stopped by blinking the charging indicator lamp in order to wait for a decrease.

  Therefore, in Patent Document 1, the charge control circuit power supply is provided with a circuit for transmitting a feedback signal to the primary power supply circuit and a resistor for reducing the output voltage at the charge output power supply, and the charge output power supply is only necessary. In addition, the power consumption of the power supply for charging output is reduced by a resistor for reducing the charging voltage, and the power supplied from the primary side power supply circuit is controlled by a feedback signal from the power supply for charging control circuit.

  Also, in Patent Document 2, in order to reduce standby power, power supply from the primary power circuit is usually stopped, and power is supplied from the battery pack when power is required to start the circuit to start charging. Like to do.

  However, in the method of Patent Document 1, it is necessary to lower the output voltage so that the feedback control is not effective, and a resistor for reducing the output voltage of the power supply for charging output requires a large allowable power.

  In addition, a circuit for a feedback signal of the power supply for the charge control circuit is necessary, which causes a cost increase. In addition, the power consumption during standby increases because a resistor is connected to drive the power supply for the charge control circuit even during standby when the battery pack is not connected.

  In Patent Document 2, since power cannot be supplied from the battery pack in a state where power cannot be supplied from the rechargeable battery pack (for example, a sleep state in which it cannot be started unless a signal is sent from the outside), the battery pack can be started by another method. Circuit is also required.

  The present invention has been made in view of the above problems, and is intended for charging output so that the power consumption of the power source for charging output is small and the output voltage of the power source for charging control circuit can be maintained even when the output of the power source for charging control circuit is large. Connect a load to the power supply to increase the power consumption of the power supply for charging output. And if the power supplied to the power supply for the charge control circuit is increased, the power consumption of the power supply for the charge output is small when the battery pack is not connected, etc. It is an object of the present invention to provide a charging apparatus that reduces power consumption during standby without adding a load to the power supply for charging output.

  At this time, since it is only necessary to slightly increase the power consumption of the power supply for charging output, the allowable power of the added resistor can be small.

  A primary power supply circuit having a switching power supply circuit for rectifying and smoothing the power supplied from the commercial power supply and controlling the power supplied to the transformer, and charging the rechargeable battery pack by controlling the charging switch for the output of the transformer Transformer power proportional to the power supplied to the charging output power from the charging control circuit and the primary side power supply circuit that receives the information of the charging output power supply and the charging battery pack and controls the charging output power supply and the charging switch. In a charging device comprising a secondary circuit comprising a power supply for a charging control circuit that supplies desired power to the charging control circuit, a load increasing circuit and a connection between the load increasing circuit are connected to the output side of the charging output power supply. A series circuit of load changeover switches is provided to reduce the power consumption of the power supply for charge output and supply the necessary power from the primary power supply circuit to the power supply for the charge control circuit. Only when there is no charge control circuit, the load changeover switch is turned on to increase the power consumption of the charge output power supply and increase the amount of power supplied to the power supply for the charge control circuit. When the power necessary for the circuit power source can be supplied, the charging device is characterized in that the load changeover switch is kept off to reduce power consumption during standby.

  In addition, a primary side power supply circuit having a switching power supply circuit for rectifying and smoothing power supplied from a commercial power supply and controlling power supplied to the transformer, and a charge battery pack by controlling a charge switch for the output of the transformer Power that is proportional to the power supplied to the power supply for charging output from the primary side power supply circuit and the charging control circuit that controls the power supply for charging output and the charging switch by receiving information on the charging battery pack and the information on the charging battery pack A resistor for increasing a load on the output side of the charging output power source in a charging device including a secondary side circuit consisting of a power source for a charging control circuit for supplying desired power to the charging control circuit supplied from a transformer And a series circuit of load changeover switches that switch the connection of this resistor, the power consumption of the power supply for the above-mentioned charging output is low, and the power supply for the charging control circuit is required from the primary power supply circuit Only when power cannot be supplied, the load control switch is turned on by the charge control circuit, and power is consumed by a resistor for increasing the load, thereby increasing the power consumption of the power supply for charge output and supplying power to the power supply for charge control circuit. Increase the power supply amount and reduce the power consumption during standby by keeping the load changeover switch off when the power required for the power supply for the charge control circuit can be supplied even when the power for the power supply for charging output is low. It is a charging device. Furthermore, the load increasing circuit can arbitrarily change the size of the load in accordance with the amount of power required for the power supply for the charging control circuit.

  According to the present invention, only when a large amount of power is required for the charging control circuit power supply, the load of the charging output power supply is increased to increase the power supplied to the charging control circuit power supply. A charging device with low standby power that reduces power can be provided.

Electrical circuit configuration diagram Each operation waveform diagram when no load increasing resistor is connected Each operation waveform diagram when a load increasing resistor is connected Charging waveform diagram of charging device in one embodiment

  Embodiments of the present invention will be described below with reference to the drawings. However, the embodiment described below specifically explains the present invention, and the present invention does not specify the charging device below.

(Embodiment 1)
FIG. 1 is an electric circuit configuration diagram schematically showing an electrical configuration of a charger constituting the charging device of the present invention.

  The charger 20 generates a predetermined current / voltage to charge the rechargeable battery of the rechargeable battery pack 10, and is electrically connected and charged by attaching the rechargeable battery pack 10 to the charger 20. To start.

  Next, the configuration of the charger 20 will be described.

  The charger 20 rectifies and smoothes an external power source (AC100V in this embodiment) into a direct current, and supplies power to the transformer 23 by the switching control circuit 22, and a secondary side from the primary side power circuit 21. The power is supplied from the transformer 23 and the transformer 23 that supply power to the power supply, and the charging current and the charging voltage are output.

  In order to output a desired charge output, a signal is fed back to the switching power supply circuit 22, and the charge output power source 24 for controlling the charge output is provided between the charge output power source 24 and the battery pack connection portion. Communication with the charge switch 25 for turning on / off the power supply and the rechargeable battery pack 10, transmission of an on / off signal of each switch, charge control, and overvoltage and overcurrent of the charge output are detected.

  A charge control circuit 27 that has a protection function for stopping charging and that controls the display lamp 28 that displays the state of charge, etc., and is supplied with power proportional to the power consumption of the power supply for charge output from the transformer 23. The charging control circuit power supply 26 for supplying power to the display lamp 28 and the output side of the charging output power supply 24 are provided on the output side, and the load of the charging output power supply 24 is required depending on the power consumption of the charging control circuit power supply 26 Load increasing resistor 29 and load increasing switch 29 for switching connection of the load increasing resistor 29 to the power supply 24 for charging output.

  In this embodiment, a resistor having a simple configuration and easy availability is used for the load increasing circuit.

  First, an operation example when the load of the power supply 24 for charging output is light and the required power is small, but the power of the power supply 26 for the charging control circuit is large will be described.

  For example, when the rechargeable battery pack 10 is attached to the charger 20, the display lamp 28 is turned on simultaneously with the attachment to inform the user of the start of charging. However, the rechargeable battery pack 10 and the charger 20 can be charged safely. Whether the BMU of the rechargeable battery pack 10 and the charge control circuit 27 of the charger 20 perform authentication communication, and charging power is not supplied to the rechargeable battery pack 10 until the authentication is completed or to charge the rechargeable battery pack 10 safely. When the temperature of the rechargeable battery pack 10 is very high or very low, the output of the power supply 24 for charging output is stopped, but the charge control circuit 27 communicates with the rechargeable battery pack 10 and the display lamp is also lit. This is the case.

  FIG. 2 is a diagram illustrating operation waveforms of the respective power supplies in such a case.

  When the load of the power supply 24 for charging output is light, in order to reduce power consumption, the triangle of the current waveform of the primary side power supply circuit 21 is small, that is, the power supplied from the primary side power supply circuit 21 is reduced. The output voltage of the power supply 24 for charging output varies within a range that does not affect the operation.

  However, it is necessary to supply power to the charge control circuit 27 and the display lamp 28, and the power required for the charge control circuit power supply 26 is large.

  In this case, since the power required for the charge output power supply 24 is small, the power supplied from the primary power supply circuit 21 to the charge control circuit power supply 26 is also reduced, and the output voltage of the charge output power supply 24 is equal to the charge control circuit 27. The voltage required for operating the battery becomes lower, and the charger 20 stops operating.

  A broken line 31 in FIG. 2 indicates a voltage necessary for maintaining the operation of the charge control circuit.

  In order not to cause such a charge stop, the load increasing resistor 29 is always connected to the output side in order to keep the power consumption of the power supply 24 for charge output above a certain level and supply power to the power supply 26 for the charge control circuit.

  Thereby, the primary side power supply circuit 21 can supply a certain level of power even when the power required for the charge output is small.

  As a result, the power supplied to the power supply for charging control circuit 26 is increased, the voltage fluctuation of the power supply for charging output 24 is reduced, and the voltage necessary for operating the charging control circuit 27 can be maintained. FIG. 3 shows the operation waveform of each power source at this time.

  However, if the load increasing resistor 29 is connected to the output side of the power supply 24 for charging output, the load increasing resistor 29 continues to consume power even during standby when the rechargeable battery pack 10 is not connected, and power consumption during standby is reduced. To increase.

  Therefore, in the present invention, a load changeover switch 30 is added in series with the load increasing resistor 29, and the charge state is always monitored by the charge control circuit 27. The charge output power supply 24 is light in load and requires less power. Only when the power consumption of the control circuit power supply 26 is large, a signal is output from the charge control circuit 27 to connect the load increasing resistor 29, and the load changeover switch 30 is turned on.

  As a result, when neither the charging output power source 24 nor the charging control circuit power source 26 is in a standby state where the rechargeable battery pack 10 is not connected, the load increasing resistor 29 does not consume power when the load is light. Power consumption can be reduced.

  A broken line 31 in FIG. 3 indicates a voltage necessary for maintaining the operation of the charge control circuit.

  FIG. 4 is a diagram illustrating waveforms at the time of on / off of the load changeover switch 30 and charging.

  When there is no load in which the rechargeable battery pack 10 is not installed or when the charging is completed and the display lamp 28 is turned off, that is, when the power supply 24 for the charge output and the power supply 26 for the charge control circuit are both lightly loaded and have low power consumption, The load changeover switch 30 is turned off at the time of charging when the load of the power source 24 is sufficiently large and sufficient power can be supplied to the charge control circuit 26, and the power is not consumed by the load increasing resistor 29 when unnecessary.

  On the other hand, the load of the power supply 24 for charging output is light and the required power is low, such that the load state is authentication communication between the rechargeable battery pack 10 and the charger 20, or the charging output is stopped due to high temperature protection. However, when the power consumption of the charge control circuit power supply 26 is large, the load changeover switch 30 is turned on to increase the power supplied to the charge output power supply 24 and increase the power supplied to the charge control circuit power supply 26. As a result, the output voltage of the power supply 26 for the charge control circuit can always maintain a stable value and maintain the charging operation.

  In the above embodiment, only one load increasing resistor 29 is connected to the output side of the power supply 24 for charge output. However, the required power of the power supply 26 for the charge control circuit varies depending on the state of the load.

  Therefore, a plurality of resistors connected to the output side of the power supply 24 for charging output are connected, and the magnitude of the resistance of the load increasing resistor 29 is switched by the load changeover switch according to the power consumption of the power supply 26 for the charging control circuit. According to a third aspect of the present invention, a large resistor is connected when the required power of the control circuit power supply 26 is large, and a small resistor is connected when the power is small, so that the power consumption of the power supply 24 for charging output is suppressed. It is the contents of.

  In this embodiment, an AC 100V external power supply is used, so the transformer 23 is used. Of course, when a DC voltage is used as an external power supply, an optimum circuit system such as a DC-DC converter can be used.

  As described above, according to the charging device of the present invention, only when the power for the charging control circuit power is necessary, the load of the charging output power source is increased to increase the power supplied to the charging control power source, and the battery pack is inserted. Thus, it is possible to provide a charging device with low standby power that reduces power consumption during standby.

DESCRIPTION OF SYMBOLS 10 Charge battery pack 20 Charger 21 Primary side power supply circuit 22 Switching control circuit 23 Transformer 24 Power supply for charge output 25 Charge switch 26 Power supply for charge control circuit 27 Charge control circuit 28 Display lamp 29 Load increase resistance 30 Load changeover switch 31 Broken line

Claims (3)

  A primary power supply circuit having a switching power supply circuit for rectifying and smoothing the power supplied from the commercial power supply and controlling the power supplied to the transformer and the output of the transformer are controlled by a charge switch to charge the rechargeable battery pack. The power is proportional to the power supplied to the charging output power from the charging control circuit and the primary side power supply circuit which receives the information of the charging output power supply and the charging battery pack and controls the charging output power supply and the charging switch. In a charging device comprising a secondary circuit comprising a power supply for a charge control circuit for supplying desired power to the charge control circuit supplied from the battery, the load increasing circuit and the load increasing circuit are connected to the output side of the charge output power supply A series circuit of load changeover switches is provided to reduce the power consumption of the power supply for charge output, and the power required for the power supply for the charge control circuit from the primary power supply circuit Even if the power cannot be supplied, the load switch is turned on by the charge control circuit to increase the power consumption of the charge output power supply, increase the power supply to the power supply for the charge control circuit, and even if the power of the charge output power supply is low A charging device characterized in that, when necessary power can be supplied to a power supply for a charge control circuit, the load changeover switch is kept off to reduce power consumption during standby.   A series circuit of a resistor for increasing the load and a load changeover switch for switching the connection of the resistor is provided on the output side of the charging output power source of the charging device, and the power consumption of the charging output power source is low. Only when the necessary power cannot be supplied from the primary power supply circuit to the power supply, the load control switch is turned on by the charge control circuit, and the power is consumed by the resistor for increasing the load. Increase the power to increase the amount of power supplied to the power supply for the charge control circuit, and when the power required for the power supply for the charge control circuit can be supplied even when the power for the power supply for the charge output is low, 2. The charging device according to claim 1, wherein the charging device is kept off to reduce power consumption during standby.   2. The charging device according to claim 1, wherein the load increasing circuit can arbitrarily change the load according to the amount of electric power required for the power supply for the charging control circuit.

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