JP2007166825A - Charging power supply and charging circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a common charging power supply that allows the charging of batteries having different charging conditions. <P>SOLUTION: The charging power supply is provided with a rectifier circuit 8 for converting an AC to a DC, a switching unit 9 for converting the DC in the rectifier circuit 8 to a high-frequency pulse wave, a conversion transformer 11 for converting the pulse wave to a prescribed voltage, first output terminals P1+, P1- for outputting power sent from the conversion transformer 11, a PWM control circuit 13 for controlling a DC output while controlling the switching unit 9, and control terminals PC+, PC- for inputting control signals to the PWM control circuit 13. A photo-coupler is operated by the control signals from the control terminals so as to input the output of the photo-coupler as a control signal to the PWM control circuit 13. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

    The present invention relates to a charging power source, a charging power source, and a charging circuit unit.

    The following patent documents disclose a charger for charging a lithium ion battery (a charger having a charging power source and a charging circuit unit). As disclosed in FIGS. 4 and 5 of this publication, a rectifier circuit 8 that converts alternating current into direct current, a switching unit 9 that converts direct current of the rectifier circuit 8 into a high-frequency pulse wave, and converts the pulse wave into a predetermined voltage A conversion transformer 11, a PWM control circuit 13 for controlling the DC output by controlling the switching unit 9, and a photocoupler 17 for inputting a control signal to the PWM control circuit 13.

    Then, when the constant current charging circuit 6 is used and the charging current exceeds a predetermined value, the photocoupler 17 is turned off, and this is used as a control signal, and the PWM control circuit 13 controls the transistor 10 to reduce the output. Control to reduce battery charging current. Therefore, the constant current charging circuit 6 prevents the battery charging current from becoming larger than the set value I1, and performs constant current charging.

When the constant voltage charging circuit 5 is used and the charging voltage exceeds a predetermined value, the photocoupler 17 is turned off, and this is used as a control signal, and the PWM control circuit 13 controls the transistor 10 to output the signal. Control it low to reduce the battery charging voltage.
JP-A-8-205418

  This charging power source and charging circuit unit cannot charge another lithium ion battery (for example, a battery with a different rated charging current). A vessel is required. In addition, when charging a Ni-Cd battery or Ni hydrogen battery with a constant current, a dedicated charger is required because the charging current is different.

  The present invention has been made to solve such drawbacks, and an object of the present invention is to provide a common charging power source that can charge batteries having different charging conditions.

    The charging power source of the present invention includes a rectifier circuit 8 that converts alternating current into direct current, a switching unit 9 that converts direct current of the rectifier circuit 8 into high-frequency pulse waves, and a conversion transformer that converts pulse waves into a predetermined voltage. 11, first output terminals P 1 + and P 1-that output power from the conversion transformer 11, a PWM control circuit 13 that controls the switching unit 9 to control DC output, and a control signal to the PWM control circuit 13. Control terminals PC + and PC− for inputting are provided. The photocoupler is operated by the control signal from the control terminal, and the output of the photocoupler is input to the PWM control circuit 13 as a control signal.

    In the charging circuit unit according to the present invention, a charging circuit unit including first input terminals I1 + and I1− that are detachably connected to the charging power source and are electrically connected to the first output terminals P1 + and P1−. The charging circuit unit includes a constant current charging circuit 6 for charging the secondary battery, and sends a control signal via the control terminals PC + and PC− so that the charging current becomes a constant current. Input to the PWM control circuit 13.

Alternatively, in the charging circuit unit of the present invention, the charging circuit unit includes first input terminals I1 + and I1- that are detachably connected to the charging power source and are electrically connected to the first output terminals P1 + and P1-. The charging circuit unit includes a constant voltage charging circuit 5 for charging the secondary battery, and sends a control signal via the control terminals PC + and PC− so that the charging voltage becomes a constant voltage. The PWM control circuit 13 is characterized by being input.
It is characterized by.

  In the present invention, the charging power source has the above-described configuration, and the charging circuit unit performs desired control by inputting a constant current or constant voltage control signal to the PWM control circuit via the control terminal. . Therefore, it is possible to supply power to a plurality of charging circuit units adapted to the charging conditions of the battery with a common charging power source.

Embodiments of the present invention will be described below with reference to the drawings. However, the examples shown below are intended to embody the technical idea of the present invention, and the present invention is not limited to the following.
A circuit diagram for charging the battery is shown in FIGS. In FIG. 1 and FIG. 2, a common charging power source A is used. In FIG. 1, a charging circuit unit B1 for charging a Ni—Cd battery and a Ni hydrogen battery with a constant current is provided. A charging circuit unit B2 for charging the ion battery with a constant current and a constant voltage is provided. A common charging power source A is detachably connected to the charging circuit portions B1 and B2. Here, the battery is detachably installed in the charging circuit portions B1 and B2.

  First, the common charging power source A will be described. The charging power source A includes an input filter 7 that removes noise included in a commercial power supply of AC 100V, a rectifier circuit 8 that converts input alternating current into direct current, and a pulse like a high-frequency pulsating flow of direct current of the rectifier circuit 8. A transistor 10 that is a switching unit 9 that converts a wave into a wave, a conversion transformer 11 that converts a pulse wave into a predetermined voltage, a rectifying and smoothing circuit 12 that rectifies the AC output of the conversion transformer 11 and converts it into a smooth DC, and switching A PWM control circuit 13 that controls the DC output by controlling the unit 9 and a photocoupler 17 that inputs a control signal to the PWM control circuit 13 are provided. Control terminals PC + and PC− for inputting a control signal to the photocoupler 17 are provided.

  The output from the rectifying and smoothing circuit 12 is supplied to the first output terminals P1 + and P1−. The charging power source A includes a constant voltage circuit 21 on the output side of the rectifying and smoothing circuit 12 so that a constant voltage can be output at the second output terminals P2 + and P2-. Such constant voltage outputs (about 5 V) from the second output terminals P2 + and P2- can be used as a power source for a mobile phone or the like.

  On the other hand, the charging circuit unit B1 of FIG. 1 is detachably attached to the charging power source A. In the attached state, the charging circuit unit B1 is connected to the first output terminals P1 + and P1− and the control terminals PC + and PC− of the charging power source A. Correspondingly, first input terminals I1 + and I1- and control terminals IC + and IC- that are electrically connected are provided.

  A charge control switch 2 connected between the positive output side of the power supply A for charging and the battery 22; a microcomputer which is an arithmetic circuit 3 for detecting the battery voltage and the charge current and controlling the charge control switch 2; Is provided.

  As described above, the charging power source A converts the input alternating current into a predetermined voltage and converts it into a direct current, and the charging circuit unit B1 controls the output voltage and output current of the charging power source A. Thus, a constant voltage charging circuit 5 and a constant current charging circuit 6 for charging the battery at a constant voltage or a constant current are incorporated.

  The charging control switch 2 is turned on when charging the battery, and turned off when the charging is completed. The charge control switch 2 is controlled by the arithmetic circuit 3. The charge control switch 2 is optimally a semiconductor switching element such as a transistor or FET, but a relay or the like can also be used.

  The constant voltage charging circuit 5 and the constant current charging circuit 6 include operation amplifiers 5A and 6A. The operation amplifier 5A of the constant voltage charging circuit 5 has a positive input terminal connected to the battery supply side. The + side input terminal is connected to a reference voltage divided by the power supply voltage Vcc from the regulator. The outputs of the operational amplifiers 5A and 6A are connected to the photocoupler 17 via a diode, a control terminal PC−, and a control terminal IC−. The constant voltage charging circuit 5 of this circuit compares the voltage of the negative input terminal of the operational amplifier 5A with the reference voltage connected to the positive side, and inverts the output (= control signal) of the operational amplifier 5A to + −. Let When the voltage of the battery (= the output voltage of the charging power source A) becomes higher than the set voltage, the negative voltage becomes higher than the positive reference voltage. Then, the output (= control signal) of the operational amplifier 5A becomes −, the diode becomes forward, current flows, and the light emitting diode of the photocoupler 17 emits light. In this state, the PWM control circuit 13 controls the transistor 10 that is the switching unit 9 to reduce the output.

  Therefore, the constant voltage charging circuit 5 prevents the charging voltage of the battery from becoming higher than the set voltage. When charging Ni-Cd batteries or Ni-hydrogen batteries, charge the battery at a constant current and set the set voltage to about 2 V / cell so that the battery voltage does not exceed the set voltage due to an abnormality. Yes.

  In the constant current charging circuit 6, the negative input terminal of the operational amplifier 6A is connected to the current detection resistor R, and the positive side is connected to the reference power supply unit. In this circuit, when the charging current of the battery becomes larger than the set value I1, the voltage of the negative input terminal of the operational amplifier 6A becomes higher than the positive reference voltage. In this state, the operating amplifier 6A sets the output voltage as-as the control signal, and causes the light emitting diode of the photocoupler 17 to emit light with the diode as the forward direction. In this state, the PWM control circuit 13 controls the transistor 10 to control the output low, thereby reducing the battery charging current. Therefore, the constant current charging circuit 6 prevents the battery charging current from becoming larger than the set value I1, and performs constant current charging.

  Although not shown, the arithmetic circuit 3 detects the positive battery voltage and the charging current of the battery 22, performs arithmetic processing on the detected signal, and controls the charging control switch 2. The arithmetic circuit 3 turns on the charging control switch 2 when starting charging, and turns off the charging control switch 2 when charging is completed.

  Further, the charging circuit unit B1 is provided with second input terminals I2 + and I2− to obtain power from an external DC power source and charge the battery 22, and a constant voltage circuit 23 that receives power from the terminals. I have. The constant voltage circuit 23 is a DC / DC converter, and lowers the voltage of the external DC power supply and supplies it to the battery 22 plus side. The constant voltage circuit 23 also performs control to detect the voltage of the current detection resistor R and output a constant current. As such an external DC power source, for example, a 12V power source for vehicles can be used. In addition, in charging circuit part B1 of FIG. 1, the set voltage of constant voltage charging circuit 5 is set to about 4.2 V / cell so that a lithium ion battery can be charged. It can also be charged.

  Next, referring to FIG. 2, the charging circuit unit B2 that can charge the lithium ion battery 22 will be described. In addition, about the structure with the same function as charging circuit part B1 of FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  A charge control switch 2 connected between the positive output side of the power supply A for charging and the battery 22; a microcomputer as an arithmetic circuit 33 for detecting the battery voltage and the charge current and controlling the charge control switch 32; Is provided.

  In the charging circuit unit B2, a constant voltage is supplied to the battery side by the constant voltage charging circuit 35. The constant voltage charging circuit 35 is mainly composed of a shunt regulator (SHG) 35B which is a conventional means. Although the output voltage of the charging power source A is supplied to the battery 22 side, the output voltage is input to Vref of the shunt regulator (SHG) 35B as the divided voltage of the resistors R1 and R2. The output of the shunt regulator (SHG) 35B and one end of the resistor R1 are connected to the photocoupler 17 via the control terminals IC + and IC− of the power supply circuit section B2 and the control terminals PC + and PC− of the charging power supply A. It is connected.

  When the output voltage of the charging power source A increases and the divided voltage increases with respect to the Vref of the shunt regulator (SHG) 35B, the current flowing into the shunt regulator (SHG) 35B is increased, and the shunt regulator ( The output voltage (= control signal) of SHG) 35B decreases. Thereby, the light emitting diode of the photocoupler 17 emits light. In this state, the PWM control circuit 13 controls the transistor 10 as the switching unit 9 to reduce the output, thereby preventing the output voltage of the charging power source A from becoming higher than the set voltage. Therefore, the constant voltage charging circuit 35 makes the output voltage of the charging power source A constant. Further, instead of the constant voltage charging circuit 35 using such a shunt regulator (SHG) 35B, an operation amplifier may be used as in the constant voltage charging circuit 5 of FIG.

  The charging control switch 32 is turned on when charging the battery, and turned off when the charging is completed. The charge control switch 32 is controlled by the arithmetic circuit 33. The charge control switch 32 can be a semiconductor switching element such as a transistor or FET.

  The arithmetic circuit 33 is connected to the positive side of the battery 22 and the current detection resistor R, detects the battery voltage and the charging current, performs arithmetic processing on the detected signals, and controls the charging control switch 2. The arithmetic circuit 33 turns on the charging control switch 32 when starting charging, and turns off the charging control switch 32 when charging is completed.

  The arithmetic circuit 32 is a microcomputer that controls so that a constant current / constant voltage power supply can be supplied to charge a lithium ion battery that has already been sold, and the charge control switch 32 is turned on and off at high speed. A constant current can be supplied to the battery 22 by detecting a voltage generated in the current measuring resistor R. The arithmetic circuit 32 can detect the voltage at the measurement point V and supply a constant voltage to the battery 22. Therefore, when the lithium ion battery is charged, constant voltage charging is performed after constant current charging of such a predetermined constant current value.

    Further, the charging circuit unit B2 is provided with second input terminals I2 + and I2- in order to obtain electric power from an external DC power source and charge the battery 22, and is a circuit that can input electric power from the terminals. As such an external DC power source, for example, a 12V power source for vehicles can be used.

It is a block diagram of the power supply for charge and charging circuit part of one Example of this invention. It is a block diagram of the power supply for charge and charging circuit part of the other Example of this invention.

Explanation of symbols

A ... charging power sources B1, B2 ... charging circuit units I1 +, I1 -... first input terminals I1 +, I1-
P1 +, P1 -... first output terminals PC +, PC -... control terminals 2, 32 ... charge control switches 3, 33 ... arithmetic circuit 5 ... constant voltage charging circuit 6 ... constant current charging circuit 7 ... input filter 8 ... rectifier circuit 9 ... Switching unit 10 ... Transistor 11 ... Conversion transformer 12 ... Rectifier smoothing circuit 13 ... PWM control circuit 14 ... Switch 17 ... Photo coupler 22 ... Battery

Claims (4)

    A rectifier circuit (8) that converts alternating current into direct current, a switching unit (9) that converts direct current of the rectifier circuit (8) into a high-frequency pulse wave, and a conversion transformer (11) that converts the pulse wave into a predetermined voltage A first output terminal (P1 +, P1-) that outputs power from the conversion transformer (11), a PWM control circuit (13) that controls the switching unit (9) to control a DC output, A charging power supply comprising control terminals (PC +, PC-) for inputting a control signal to the PWM control circuit (13).     The charging power supply according to claim 1, wherein a photocoupler is operated by the control signal from the control terminal, and an output of the photocoupler is input to the PWM control circuit (13) as a control signal. In the charging power source, a rectifier circuit (8) for converting alternating current into direct current, a switching unit (9) for converting direct current of the rectifier circuit (8) into a high-frequency pulse wave, and converting the pulse wave into a predetermined voltage PWM control for controlling the DC output by controlling the conversion transformer (11), the first output terminals (P1 +, P1-) for outputting electric power from the conversion transformer (11), and the switching unit (9). A control terminal (PC +, PC-) for inputting a control signal to the circuit (13) and the PWM control circuit (13);
A charging circuit unit including a first input terminal (I1 +, I1-) that is detachably connected to the charging power source and electrically connected to the first output terminal (P1 +, P1-);
The charging circuit unit includes a constant current charging circuit (6) for charging the secondary battery, and sends a control signal via the control terminals (PC +, PC-) so that the charging current becomes a constant current. A power supply for charging and a charging circuit section, which are inputted to the PWM control circuit (13). In the charging power source, a rectifier circuit (8) for converting alternating current into direct current, a switching unit (9) for converting direct current of the rectifier circuit (8) into a high-frequency pulse wave, and converting the pulse wave into a predetermined voltage PWM control for controlling the DC output by controlling the conversion transformer (11), the first output terminals (P1 +, P1-) for outputting electric power from the conversion transformer (11), and the switching unit (9). A control terminal (PC +, PC-) for inputting a control signal to the circuit (13) and the PWM control circuit (13);
A charging circuit unit including a first input terminal (I1 +, I1-) that is detachably connected to the charging power source and electrically connected to the first output terminal (P1 +, P1-);
The charging circuit unit includes a constant voltage charging circuit (5) for charging a secondary battery, and a control signal is sent via the control terminals (PC +, PC−) so that the charging voltage becomes a constant voltage. A power supply for charging and a charging circuit section, which are inputted to the PWM control circuit (13).

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