KR100453883B1 - charge device of battery - Google Patents

Abstract

The present invention relates to a battery charging device, and is configured to accurately display the charging state and the current operating state of the charging device, so that the user can more easily grasp the state of the charging device, according to the ambient conditions such as temperature A microcontroller unit for converting analog signals inputted from a plurality of input terminals into digital signals so as to extend the lifespan of the battery by varying charging currents, and calculating and controlling the signals by a preset program, and outputting the signals to an output terminal; A transformer unit which receives a commercial AC voltage and interworks with changes in temperature and current, and converts the input voltage into a low voltage and outputs the low voltage; A phase and frequency detector detecting a waveform of the transformer and detecting a phase and a frequency of an input voltage; A constant voltage circuit unit rectifying the output of the transformer unit and converting the output into a constant voltage; A phase control unit configured to phase-control the output of the transformer unit with a control signal of the microcontroller unit and output the pulse stream; A battery state detection unit having a charge voltage, a current, and an internal temperature detection circuit of the battery; An internal temperature detector configured to measure an internal temperature according to a temperature change of the transformer unit and the phase control unit; And a status display unit for displaying the current operation status.

Description

Battery charging device

The present invention relates to a battery charging device. More specifically, a microcontroller and a phase control semiconductor device convert a commercial AC voltage into a low voltage using a transformer, and control a phase of the converted low voltage AC into a constant current battery. To maintain a good state of charge by constantly changing the charging current to suit the current state of the battery, transformer, etc., and short-circuit, disconnection, poor terminal contact, and error due to temperature rise The LEDs can be displayed differently using LEDs to eliminate problems that occur beforehand.The full charge detection is performed by detecting the full charge by the time of the thermostat operation, -dV, and the charging current, so that there is no overcharge. It relates to a battery charging device that can extend the life of the battery.

1 is a circuit diagram illustrating an electrical configuration of a conventional battery charging apparatus using a relay, which will be described below with reference to the related art.

As shown, the commercial AC voltage is converted into the low voltage through the transformer T1, and the AC voltage converted into the low voltage is rectified through the bridge diode BD1, thereby becoming a pulse current.

Even when the battery BT1 is connected to the battery connection terminal, the contact of the relay K1 remains open until the switch SW1 is operated. When the switch SW1 is operated, power is applied to the coil of the relay K1, and the contact is turned on. Then, the electrical connection state is maintained and the pulsed rectified to the battery BT1 is continuously supplied even when the switch SW1 is turned off. .

On the other hand, the thermostat SW2 has a contact in the normal use state and maintains the connected state, but when the temperature reaches a predetermined temperature, for example, approximately 45 ° C. or more, the contact drops.

In the initial stage of charging, the battery BT1 hardly generates heat due to an internal chemical reaction in the endothermic panel, but after the charging is completed, the battery BT1 generates heat and becomes a high temperature.

Then, the thermostat SW2 is operated to stop the power supply to the relay K1, and thus the current supplied to the battery BT1 is also cut off to complete the charging.

The light emitting diode LED1 operates simultaneously with the relay K1 to indicate the charging state, and the diode D3 prevents current from flowing back into the charging device due to a misconnection of the battery BT1.

Of course, the voltage of the relay K1 smoothes the pulse flow rectified through the diodes D1 and D2 through the capacitor C1 to prevent shaking of the relay K1.

Meanwhile, FIG. 2 is a circuit diagram illustrating an electrical configuration of a conventional battery charging apparatus using a transistor, and another conventional technique will be described below with reference to this.

The commercial AC voltage is converted into the low voltage through the transformer T1, and the converted AC voltage is rectified again through the bridge diode BD1, and smoothed through the capacitor C1.

In the above state, when the battery pack consisting of the battery BT1 and the thermostat SW2 is connected to the terminal and the start button SW1 is pressed, the output of the self-holding circuit composed of the two NAND gate inputs is kept high. While turning on the transistor Q3, current flows through the transistor Q3 and the resistor R7 to the battery through the constant current circuit composed of the transistor and the resistor. At this time, the operation of the constant current circuit is performed by the resistor R2 and the transistor Q1. And are supplied to the battery BT1 through the diode D1.

The amount of this current is sensed by the transistor Q2 as the voltage across the resistor R2, and when an abnormal voltage occurs at both ends, the emitter and the collector of the transistor Q2 are turned on and supplied to the base of the transistor Q1. The current flows toward the emitter, which reduces the current flowing to the base and consequently increases the resistance between the emitter and the collector, reducing the flow of current, limiting the current to maintain a constant current.

At the time of full charge, the thermostat SW2 operates like the relay circuit described above, and the self-holding circuit is released, and the output of the NAND gate is brought low to turn off the operation of the transistor.

The current for the trickle charge flows through the resistor R1 to make the initial battery ready for charging, and it is not turned on even when the thermostat in the case of the battery or the terminal is defective, thereby ensuring the safety of the charging device.

The diode D1 is for preventing the reverse flow of the current due to the incorrect connection of the battery, and the light emitting diode LED1 is a lamp indicating the state of charge.

However, the conventional charging device using such a conventional relay or transistor has the following problems.

First, a charging device using a relay has to use a different transformer because the design of the transformer must be different when the charging completion voltage is different for each battery, and at this time, the relay voltage must also use a different type of components. There is a problem.

In addition, by using the secondary winding of the transformer to limit the current, the heat generation of the transformer also has a big disadvantage.

In addition, the secondary voltage is determined to meet the charging time at 85% of the rated voltage input.In the case of 110%, the bridge diode should be used with a large capacity due to the overcurrent that the charging current becomes larger than necessary. An abnormal temperature rise occurs. At this time, even if the battery is not fully charged due to the abnormal temperature rise, the thermostat operates to complete the charging, and there is a problem in that its life is shortened due to overheating of the battery.

On the other hand, since only the internal temperature of the battery is detected to detect the completion of charging, if the thermostat does not operate even after full charge, the battery life due to overcharging of the battery is shortened.

In addition, since there is no trickle charge after the charging is completed, a natural discharge of the battery may occur in a state of being inserted into the charging device.

In addition, mechanical operating noise is generated by using a mechanically operated relay, and defects due to contact failure and contact wear occur.

Of course, there is a disadvantage in that it does not detect a problem when charging a defective or short-circuit battery.

That is, when the positive (+,-) of the battery is disconnected, the thermostat inside the battery does not operate and is displayed as being charged even if it is not charged.

In addition, when the battery positive (+,-) is short-circuited, excessive current flows through the transformer and the bridge diode to generate heat, thereby destroying the component.

In addition, when the thermostat is disconnected, the charging operation is not performed. When the thermostat is shorted, the charging completion function is not detected by -dV detection after full charge and the charging completion is detected only by the thermostat operation. Due to the shortening of the life of the battery, it will not display the charge completion.

In addition, the charging device using the transistor also has the same problem of short circuit and disconnection inside the battery as in the charging device using the relay.

Therefore, the present invention has been made to solve the above-mentioned conventional problems, by converting a commercial AC voltage to a low voltage by using a transformer using a microcontroller and a phase control semiconductor device, and phase-control the AC of the converted low voltage It charges the battery with constant current, maintains a good charging state by constantly changing the charging current to suit the current state of the battery, transformer, etc., and prevents short-circuit, disconnection of the battery, poor terminal contact, and temperature rise. The errors caused by LEDs can be displayed differently by using different LEDs, and problems can be eliminated in advance, and full charge detection can be overcharged by detecting full charge with time according to the operation of the thermostat, -dV, and charging current. To provide a battery charging device that can extend the life by .

1 is a circuit diagram showing the electrical configuration of a conventional battery charging device using a relay.

2 is a circuit diagram showing the electrical configuration of a conventional battery charging apparatus using a transistor.

3 is a block diagram showing the electrical configuration of the battery charging apparatus according to the present invention.

Figure 4 is a detailed circuit diagram showing the electrical configuration of the battery charging apparatus according to the present invention.

5 is a detailed circuit diagram showing another electrical configuration of the battery charging apparatus according to the present invention.

6 is a detailed circuit diagram showing another electrical configuration of the battery charging apparatus according to the present invention.

Explanation of the Major Codes in the Drawing

10; A microcontroller unit 20; Transformer section

30; Phase and frequency detector 40; Constant voltage circuit

50; Phase controller 60; Battery status detector

70; An internal temperature detector 80; Status display

In order to achieve the above object, the battery charging apparatus according to the present invention converts analog signals inputted from a plurality of input terminals into digital signals, calculates and controls them by a preset program, and outputs the signals to an output terminal; A transformer unit which receives a commercial AC voltage and interworks with changes in temperature and current, and converts the input voltage into a low voltage and outputs the low voltage; A phase and frequency detector detecting a waveform of the transformer and detecting a phase and a frequency of an input voltage; A constant voltage circuit unit rectifying the output of the transformer unit and converting the output into a constant voltage; A phase control unit configured to phase-control the output of the transformer unit with a control signal of the microcontroller unit and output the pulse stream; A battery state detection unit having a charge voltage, a current, and an internal temperature detection circuit of the battery; An internal temperature detector configured to measure an internal temperature according to a temperature change of the transformer unit and the phase control unit; And a status display unit for displaying the current operation status.

Here, the microcontroller unit supplies a constant current to the battery by performing phase control using a phase control semiconductor device according to a current battery state of charge.

In addition, the microcontroller unit changes the constant current value of charging according to the temperature change of the battery and supplies it to the battery.

In addition, the status display unit displays differently depending on the battery connection failure, charging, standby, charging completion and internal temperature conditions.

In addition, the microcontroller unit detects a full charge state according to the battery voltage change and the control current time during charging.

According to the battery charging device according to the present invention as described above, it is configured to accurately display the state of charge and the current operating state of the charging device that has not been performed in the conventional charging device, the user can more easily grasp the state of the charging device In addition, it is possible to extend the life of the battery by changing the charging current according to the ambient conditions, such as temperature.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings such that those skilled in the art may easily implement the present invention.

3 is a block diagram showing the electrical configuration of the battery charging apparatus according to the present invention.

As shown in the drawing, the battery charging apparatus according to the present invention converts analog signals input from a plurality of input terminals into digital signals, calculates and controls them by a preset program, and outputs the signals to an output terminal. The transformer unit 20 receives an AC voltage and changes the temperature and current, and simultaneously converts the input voltage into a low voltage and outputs a waveform from the transformer unit 20 to detect a waveform of the input voltage phase and frequency. Phase and frequency detection unit 30 for detecting the constant voltage circuit unit 40 for rectifying and converting the output of the transformer unit 20 to a constant voltage, the control of the microcontroller unit 10 to the output of the transformer unit 20 Phase control unit 50 for controlling the phase by a signal and outputting as a pulse flow, and the charging voltage, current and internal temperature detection circuit of the battery The battery state detection unit 60, the transformer unit 20 and the phase control unit 50 consists of an internal temperature detection unit 70 for measuring the internal temperature according to the temperature change, and a status display unit 80 for displaying the current operating state have.

On the other hand, Figure 4 is a phase control device SCR (thyristor), Figure 5 is a phase control device FET (Field Effect Transistor), Figure 6 is a phase control device using a transistor as the electrical charge of the battery charging apparatus according to the present invention A detailed circuit diagram showing the configuration, respectively, will be described in detail with reference to the configuration and operation of the above-described parts in conjunction with FIG.

First, the transformer unit 20 is a transformer T1 for converting a commercial AC voltage into a low voltage at a constant ratio, and is inserted into the transformer T1 to raise an internal temperature to approximately 135 ° C. or to overcurrent the primary winding. It consists of the fuse F1 disconnected when it flows.

In addition, the phase and frequency detection unit 30 is transformed from the transformer T1 to the commercial AC voltage is input to the battery at a constant period and a constant AC voltage, the AC voltage is changed to a low current through the resistors (R6, R7) Because of this, it changes to digital high and low. The voltage detected as high and low in this manner is that the AC input is in the + range when high is detected and the -in the case when the input is low. In this way, the current state and period of the input angle can be known by calculating the internal time of the microcontroller 10 to be changed from high to low so that the phase control semiconductor device (SCR, FET or transistor) is turned on or off. The time point is determined.

In addition, in the constant voltage circuit unit 40, the voltage rectified through the secondary side of the transformer T1 and the diodes D5 and D6 is changed to the direct current through the capacitor C1, and the DC voltage is the state display unit 80 to be described below. It is used as a power source of the light emitting diode LED1 and maintains a constant voltage using the breakdown voltage of the zener diode ZD1 after passing through the resistor R1.

The constant voltage obtained above is also used as the operating voltage of the microcontroller 10 and the reference voltage of the analog / digital converter included in the microcontroller 10.

Subsequently, the battery state detection unit 60 is mainly composed of a charge voltage detection circuit, a charge current circuit, and a battery internal temperature detection circuit of the battery.

First, the charging voltage of the battery is the voltage between the resistors R10 and R11. The voltage divided by the resistors R10 and R11 is input to the analog / digital converter of the microcontroller 10 to detect the current charging voltage. The current state of charge of the battery may be determined using the detected voltage, and short-circuits and disconnections at both ends of the battery may be detected, and a contact connection with the charging device may be detected.

The charging current of the battery detects the voltage across the resistor R17, passes the resistor R16, takes an average value by the capacitor C5, and is input to the analog / digital converter of the microcontroller 10 to detect the current charging current. As a result, the detected current can control a constant current to maintain a constant current, detect short circuits and disconnections at both ends of the battery, and detect contact connection with a charging device.

The internal temperature of the battery may be detected by the thermostat SW2 or thermistor TH2 connected to the negative terminal of the battery in the battery pack.

In the case of the thermostat SW2, the temperature inside the battery pack is detected by detecting a low in the off state and a high in the on state as a digital signal for detecting on and off according to a constant temperature.

In the case of thermistor TH2, the resistance value changes as the temperature changes, and the voltage value converted by the voltage distribution circuit configured together with the resistor R15 is passed through the resistor R14 to the analog / digital output of the microcontroller 10. It is input to the converter to detect the current temperature inside the battery to detect the change of the charging current according to the temperature and the connection with the contact of the charging device.

Next, when the charging device charges for a long time, the internal temperature detector 70 generates heat from the transformer T1 and the phase control semiconductor elements Q1 and Q4, thereby increasing the internal temperature. At this time, if the charging continues, the thermal fuse F1 inside the transformer T1 is disconnected due to overheating. In order to prevent the above-mentioned phenomenon, the voltage value converted by the voltage distribution circuit configured with the thermistor TH1 in which the voltage from the constant voltage unit changes with the resistance R20 and the temperature changes is converted into a microcontroller unit ( It is input to the analog / digital converter of 10) to detect the current internal temperature of the charging device and change the charging current according to the temperature change of the charging device.

In addition, the phase controller 50 may convert the AC voltage transformed by the transformer T1 according to the state of charge of the battery, the internal temperature, the charging current, and the internal temperature of the charging device using the phase control semiconductor elements Q1 and Q4. With the signal controlled in the section 10, the width of the signal for one on / off cycle per cycle, the SCRs Q1 and Q4 use the transistors Q2 and Q3 (see FIG. 4), and the FET Q1. Uses a port of the microcontroller unit 10 (see FIG. 5), and the transistor Q1 uses a transistor Q2 (see FIG. 6) to apply a voltage to the gate and the base to control the rectified pulse flow. Output to charge the battery with constant current.

In addition, the status display unit 80 emits light during charging, completion of charging, poor contact between the battery terminal and the contact of the charging device, high and low temperature generation inside the battery, and high and low temperature generation inside the charging device. This is a diode (LED1), which informs different operations.

The microcontroller 10 determines the charging current and the charging voltage of the battery, the state of charge of the battery, the full charge, the completion of charging, etc. by using the detected values such as the charging voltage, the charging current, and the temperature detected through each detection unit. The phase controller 50 and the state display unit 80 are controlled.

The control method of the microcontroller 10 will be described below.

When the battery is inserted into the contacts (+,-, TH) of the charging device, the voltage of the battery is detected through the (+) and (-) contacts through the state detection unit 60, and information about the temperature through the (TH) contact Is detected.

When the voltage of the battery is detected but not detected for the temperature, it is detected by the opening of the (TH) terminal to indicate a defective contact on the status display unit 80.

When the insertion of the battery is detected, the microcontroller unit 10 gradually increases the charging voltage through the phase controller 50. At this time, the charging current is increased accordingly and a constant current is output.

Charging starts when the charging voltage rises above the initial detected voltage. At this time, if the current is not detected by detecting the (+) terminal or (-) terminal open to display the contact failure on the status display unit (80).

When the current rises to maintain a constant current while maintaining charge, if the voltage fails to rise above a certain voltage, a short circuit of the (+) and (-) terminals is detected and a battery short circuit is displayed on the status display unit 80.

During the initial charging, when the internal temperature of the battery pack or the charging device is low, the battery is charged to be charged, and the battery is charged by raising the temperature of the battery at regular intervals to start charging.

If the above does not occur, charging is continuously performed at a current set in the past, and a voltage, a current, an internal temperature of the battery pack, and an internal temperature of the charging device are detected at regular intervals.

When there is a change in the detected current, the controlled output of the phase control semiconductor element (SCR, FET or transistor) of the phase controller 50 is controlled to maintain a constant current.

Heat is generated during the charging of the phase control semiconductor elements Q1 and Q4 and the transformer T1 of the charging device. If excessive heat is generated, the element may be destroyed or the fuse F1 may be disconnected inside the transformer. have.

The microcontroller 10 detects such a change in temperature and changes it to a charging current according to a previously set temperature so that the microcontroller 10 is charged with a current lower than the constant current initially charged to slow down the heat generation rate. To control.

In the case of a Ni-cad or hydrogen battery, the voltage is lowered when charging is completed. This is called -dV and there is no change in voltage even when the charging is continued. This is called 0dV. Will rise.

Full charge detection by -dV may have slightly different characteristics for each battery since the batteries are connected in series in the battery pack. If dV is detected within a certain time after charging starts, it is not detected as a full charge and it is charged one more time and charged until -dV is detected after the voltage rises.

In the case of 0dV, when the constant current is charged with a constant current for a certain time, it is determined as full charge when there is no voltage change.

In the case of full charge of the battery, if a temperature above a certain temperature is detected, it is determined as full charge.

When the microcontroller 10 determines the full charge, the microcontroller 10 controls the phase controller 50 to convert the rapid charge to trickle charge, operates the phase controller 50 at a predetermined cycle to charge the battery, and displays the completion of the charge on the status display unit.

As described above, although the present invention has been described with reference to the above embodiments, the present invention is not limited thereto, and various modifications may be made without departing from the scope and spirit of the present invention. For example, in the present invention, the battery pack internal temperature detector may be removed to prevent the microcontroller from operating for the detection, and thus may be used as a charger for a general rechargeable hydrogen battery and a NiCad battery.

Therefore, the battery charging device according to the present invention is configured to accurately display the state of charge and the current operation state of the charging device that has not been performed in the conventional charging device, so that the user can more easily grasp the state of the charging device, the temperature There is an effect that can extend the life of the battery by changing the charging current according to the surrounding situation.

Claims (5)

(Correction) A microcontroller unit which converts analog signals input from a plurality of input terminals into digital signals, calculates and controls them by a predetermined program, and outputs the signals to an output terminal; A transformer unit which receives a commercial AC voltage and interworks with changes in temperature and current, and converts the input voltage into a low voltage and outputs the low voltage; A phase and frequency detector for detecting a phase and a frequency of an input voltage by detecting a waveform in the transformer unit, and outputting a high and low signal that can be handled by the microcontroller using a plurality of resistors; A constant voltage circuit unit rectifying the output of the transformer unit to convert the output into a constant voltage and supplying the constant voltage to the micro controller unit; A phase control unit configured to phase-control the output of the transformer unit with a control signal of the microcontroller unit and output the pulse stream; A battery state detection unit having a charge voltage, a current, and an internal temperature detection circuit of the battery; An internal temperature detector configured to measure an internal temperature according to a temperature change of the transformer unit and the phase control unit; And, Charging apparatus for a battery comprising a status display for displaying the current operating state. The battery charging apparatus according to claim 1, wherein the microcontroller unit supplies a constant current to the battery by controlling the phase by using a phase control semiconductor device according to a current battery charging state. The battery charging apparatus of claim 1, wherein the micro controller is configured to supply a battery by changing a charging constant current value according to a temperature change of the battery. The apparatus of claim 1, wherein the state display unit displays differently according to a battery connection failure, charging, standby, completion of charging, and internal temperature. The apparatus of claim 1, wherein the microcontroller unit detects a full charge state according to a change in battery voltage during charging and a time of a control current.