KR100198277B1 - Switching type charger - Google Patents

Abstract

The present invention relates to a switching charging device that is suitable for electric forklifts, electric vehicles, industrial large capacity storage batteries (batteries), but with good durability, safety, and economics of a charging device.

According to an aspect of the present invention, there is provided a charging device for charging a large capacity battery, comprising: a first switching unit configured to supply and block a voltage RST input from a power input terminal AC while turning on and off switches MC1-S; A second switching unit for switching the AC voltage input through the first switching unit, a bridge diode for rectifying the AC voltage input through the second switching unit, an electrolytic capacitor charged with the voltage output from the bridge diode, and a pulse width; A switching element for outputting a predetermined square wave signal while receiving an altered switching drive, a transformer for converting a signal voltage output from the switching element, and full-wave rectifying a signal output from the transformer, A current transformer for smoothing the current of the smoothed voltage and a DC voltage smoothed through the current transformer are charged to the storage battery. It is characterized by being made.

Description

Switching Charger

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching charging device, and more particularly, to a switching charging device suitable for precise charging of an electric forklift, an electric vehicle, and an industrial large capacity battery (battery), and having good durability, safety, and economy of the charging device.

Conventional charging device has a magnetoresistance current control charging method (REAKAGE TYPE) and SCR charging method, the magnetoresistance current control charging method (REAKAGE TYPE) is the battery charger of the most widely used battery, the core of the transformer The method of controlling the charging current according to the leakage flux using the gap has the advantage of simple circuit diagram.The charging state is determined by the battery voltage and transformer characteristics, and it has a passive charging algorithm. Due to the characteristics of this charger, it is difficult to make precise charging and safety charging.In particular, in the workplace where the input voltage is irregular, uncontrollable overcurrent may flow, and by using a large transformer, the weight is heavy, bulky, and manufacturing cost. Has a problem that is consumed a lot.

In the case of the SCR charger, a second-generation charger that compensates for the shortcomings of the magneto-resistive current control charging type (REAKAGE TYPE) is used to control the current and voltage by controlling the phase using SCR instead of using the inductance of the RIKEAGE transistor. This is because the loss of power is smaller than that of the magnetoresistive current control charging method, but there are still losses in large transformers and reactors, and it is difficult to improve because of the analog type control method, and the volume varies considerably according to the capacity of the battery. In addition, when the current capacity is increased, as in the magnetoresistive current control charging method, it is heavy and bulky, and a transformer and a reactor must be used, and thus production cost is significantly higher than that of the magnetoresistive current control charging method.

An object of the present invention is to configure a microcomputer and a high-speed switching device in the charging device for charging the battery to precisely control the charge control digitally, so that the constant current can be charged to maintain a good state of charge and long life of the battery I want to,

Another object of the present invention is to configure the self-diagnostic means in the charging device to charge, not only to detect the occurrence of abnormality during charging in advance, but also to provide a safety, durability, economy of the charging device.

In order to achieve the above object, the present invention provides a charging device for charging a large capacity battery, comprising: supplying and blocking a voltage (RST) input from a power input terminal (AC) while turning on and off switches MC1-S; A first switching unit, a second switching unit for switching an AC voltage input through the first switching unit, a bridge diode for rectifying the AC voltage input through the second switching unit, and a voltage output from the bridge diode A switching device for outputting a predetermined square wave signal while alternately switching and driving a pulse width modulated signal, a transformer for converting a signal voltage output from the switching device, and a signal output from the transformer A rectifier for rectifying and smoothing the rectified voltage to sense current of the smoothed voltage, and a smoothed rectifier through the current transformer. That the voltage charged in the storage battery arranged to hayeoseo characterized.

1 is an overall control block diagram for the switched charging device of the present invention.

2 is a detailed circuit diagram of a charging unit of the switching type charging device of the present invention;

Figure 3 (a) is the input waveform diagram of the switching element of the present invention charging section

Figure 3 (b) is an output waveform diagram of the switching element of the charging unit of the present invention

Figure 4 is a charge current and voltage waveform diagram of the switching charger of the present invention

Explanation of symbols for main parts of the drawings

end; Mycomb me; Rectifier

All; Imaging check d; Over Current Detector

hemp; Temperature sensing bar; Fault detection department

four; Emergency detection unit; Current sensing part

character; Voltage sensing unit difference; Equal Charge

Ka; Micro switch driving part; Pulse Width Modulation Drive Output

wave; Charging load; Display

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is an overall control block diagram of a switching type charging device according to the present invention, which controls various signals inputted from an input terminal by a predetermined program and outputs the controlled signals through each output terminal to control the entire apparatus. The microcomputer (A), the rectifier (B) for rectifying the AC voltage inputted from the power input terminal (AC) into a predetermined DC voltage, and the three-phase AC voltage input from the power input terminal (AC). The phase checking unit (C) which checks whether any phase of UVW is missing and the transient signal is sensed when the overload and switching element (IGBT) and the device are short-circuited at the output terminal by the control signal of the microcomputer (A). An overcurrent detecting unit (D), a temperature detecting unit (E) for detecting an overheating temperature of the heat sink mounted on each element according to the control signal of the microcomputer (A), and the control unit of the microcomputer (A) The output stage fuse abnormality detection part (bar) which detects the connection or fuse short-circuit state by overload and storage battery by reverse direction, the emergency detection part (g) which stops the operation of the microcomputer in case of emergency, and the minimum when charging A current sensing unit (h) for detecting whether the current and the maximum current operate within a set current range, a voltage sensing unit (i) for sensing the voltage at the output terminal according to the control signal of the microcomputer (b); If the predetermined constant voltage is maintained during charging by the control signal of the microcomputer (a), the equalizing unit (car) for supplying the terminal current for a predetermined time and the relay for controlling the relay drive by the control signal of the microcomputer (a) Pulse width modulation for outputting the modulated signal and pulse width modulation of the signal output by the driving unit (K) and the control signal of the microcomputer (A) and the pulse width modulator for outputting the driving signal. An abnormality is displayed by an output unit (ta), a charging unit (wave) for charging current and voltage by the drive signal output from the pulse width modulation drive output unit (ta), and a control signal of the microcomputer (a). It consists of a display part (bottom).

FIG. 2 is a detailed circuit diagram of a charging unit of the switching type charging device according to the present invention.

A first switching unit (A) comprising a micro switch (MC1) and a relay (RY1) for supplying and cutting off the voltage (RST) input from the switch MC1-S while turning on and off the switches MC1-S, and the first switching. The second switching unit (B) consisting of a micro switch (MC2) and a relay (RY2) for switching the AC voltage input through the unit (A), and the AC voltage input through the second switching unit (B) Bridge diode BD1 composed of rectifying diodes D1-D6, and an electrolytic capacitor C1 charging the voltage output from the bridge diode BD1 through a resistor R1 and a switch MC2-S ( C2) and a switching element IGBT1 that receives a pulse width modulated signal from the microcomputer and outputs a predetermined square wave signal while alternately switching driving.

(IGBT2), a transformer (T1) for converting the signal voltage output from the switching elements (IGBT1) (IGBT2), and a diode (D7) (D8) for full-wave rectifying the signal output from the transformer (T1); The diodes D7 and D8 have a coil L for smoothing the rectified voltage. By connecting a current transformer (CT) for sensing the current of the voltage smoothed by the coil (L), and a storage battery (BAT) for charging a direct current to the output terminal of the current transformer (CT) through a resistor (R2) capacitor (C3) will be.

Referring to the effects of the present invention configured as described above are as follows.

First, when the battery BAT to be charged is connected to the output terminal of the output unit of FIG. 2, the microcomputer A detects and measures the capacity and state of the battery BAT connected to the output terminal through the voltage sensing unit. By setting the charging current and the charging time to charge the storage battery BAT by a predetermined program, at this time, depending on the voltage state remaining in the battery BAT to be charged When the voltage of the battery BAT is less than 37 V, the battery BAT is completely discharged and cannot be charged.

When the charging current and the charging time are determined according to the voltage state of the battery BAT to be charged as described above, the microcomputer (A) outputs the constant voltage state through the rectifying unit (B) and the output terminal through the overcurrent sensing unit (D). It detects whether overcurrent flows to each element and also senses heat of the heatsink mounted on each element through the temperature detector (e), and overload and accumulator to the output terminal in reverse direction through the fuse abnormality detector (bar). Detects abnormal state by detecting connection or fuse short status and checking whether any phase of three phase AC voltage (UVW) inputted from power input terminal (AC) through the phase check unit (C). At this time, the state detected by each of the detection unit is displayed by turning on and off through the display unit (lower), and when an abnormality occurs in the detected state, Through the portion (G) to thereby stop the operation of the microprocessor (A).

When the abnormal state of the device is checked as described above, the microcomputer (A) controls the micro switch driving unit (K) to operate the relay RY1 of the first switch unit A shown in FIG. When the MC1 is turned on, the three-phase voltage of the power input terminal RST is applied to the bridge diode BD1 through the micro switch contacts MC1-S. Check whether any phase of the three-phase AC voltage (UVW) input from the power input terminal (ACW) is missing, and if any of the phases of the three-phase AC voltage (UVW) is missing, the microswitch drive unit (K) ) To cut off the output, block the input voltage to prevent the micro switch MC1 from operating, and control the display (bottom) to display an error.

On the other hand, the AC voltage input to the bridge diode BD1 is rectified to DC and gradually starts charging to the capacitors C1 and C2 through the resistor R1. In the microcomputer A, the micro switch driver (K) By operating the relay RY2 of the second switch unit B shown in FIG. 2 to turn on the micro switch MC2, the second switch unit B is the first switch unit ( 5 seconds after the operation of A), the voltage rectified by the bridge diode BD1 is charged to the capacitor C1 and C2 through the resistor R1 and the micro switch MC2 after 5 seconds. This will be.

The operation of the micro switch MC2 after 5 seconds is to prevent the occurrence of an arc in the micro switch MC2 when a surge voltage is generated when a large current flows suddenly through the capacitors C1 and C2.

When the charging of the capacitors C1 and C2 is completed as described above, the microcomputer A controls the microcomputer A for a predetermined delay time (8 seconds) to detect an abnormal state. If this occurs, the microcomputer (A) controls the micro switch driving unit (car) to stop the operation of the micro switch MC1 (MC2) of the first switch unit (A) and the second switch unit (B) as well as emergency The control unit (g) is controlled to stop the operation of the device.

On the other hand, when the abnormal state is not detected, the microcomputer (a) controls the pulse width modulation drive output unit (ta) to pulse width modulate the signal output from the microcomputer (a), and the modulated signal is driven by the driver. When a signal is applied to the gate terminal of the switching elements IGBT1 and IGBT2 of the charging unit (wave) as shown in FIG. 3 (a), the output terminal of the switching elements IGBT1 and IGBT2 is connected to FIG. The square wave as shown in b) is outputted, and the voltage output from the output terminal of the switching elements IGBT1 and IGBT2 is induced on the secondary side via the primary side of the transformer T1, so that the diodes D7 and D8 are applied. After converting into a predetermined DC voltage through each of the through and smoothed in the coil (L) and through the current transformer (CT) to charge the DC voltage to the capacitor (BAT) connected to the output terminal, through the current transformer (CT) The output current flows through the current sensing unit. Standing set up, thereby the charging and detecting the minimum current.

At this time, for example, when the AC input voltage is 220V three-phase, and you want to charge the 48 V 550 AH lead-acid capacitor (BAT), the initial current is set to 75A, the terminal current is set to 25A, and the voltage of the battery at constant voltage is 58.6V In the case of starting charging, as shown in FIG. 4, the soft start is started, and when the current reaches 7.5 A to 75 A, the current is continuously applied at 75 A until the voltage of the battery reaches 58.6 V.

At this time, the applied time is 5 hours. Then, when the voltage of the battery reaches 58.6 V through the voltage sensing unit, the microcomputer changes to the constant voltage mode and the current falls and the current sensing unit (H) After sensing current of current transformer (CT) through 25A, when current reaches 25A, it is converted to constant current mode and current is continuously applied to storage battery at 25A. At this time, the battery is charged for 3 hours and the total charging time is charged for 8 hours.

On the other hand, in consideration of the safety, the maximum current is set to 85 A, and when the 85 A is exceeded, the overcurrent detecting unit (D) stops the charging operation, and when the battery to be charged exceeds 65 V, the voltage sensing unit (R) Stops charging operation by detecting voltage and displaying abnormal voltage.

In addition, the battery performs an equal charge about once a month. At this time, when the equal switch is turned on by controlling the equal charging unit (car), the terminal current 25A flows for about 6 hours. At this time, if the charging is normally completed, the microcomputer (a) controls the display unit (bottom) to display the completion of charging and stops the charging operation.

As described above, according to the present invention, the charging current is controlled by the microcomputer and the pulse width modulated signal to control the high speed switching device, so that the structure is simple, so that the device can be stabilized, reduced in weight, and precisely charged. It is equipped with the function to diagnose overcurrent, overvoltage, phase check, overcharge protection, and input voltage during charging, so that constant current can be supplied regardless of input voltage fluctuations to maintain the ideal charging state. It will provide an effect that can be done.

Claims (2)

The microcomputer (A) which controls various signals inputted from the power input terminal (AC) by a predetermined program and outputs the controlled signal through each output terminal, and controls the whole device, and the power input terminal (AC). An overload and switching element (IGBT) and a device short-circuit at the output terminal by the phase checking unit (C) for checking whether any phase of the three-phase AC voltage (UVW) input from the phase is broken and the control signal of the microcomputer (A). And an overcurrent sensing unit (D) for detecting an overcurrent, a temperature sensing unit (E) for sensing an overheating temperature of a heat sink mounted on each element according to the control signal of the microcomputer (A), and the microcom (A) An output stage fuse abnormality detection unit (bar) for detecting an overload and a battery short-circuit connected or a fuse short-circuit state by a control signal of a; and an emergency detection unit (g) for stopping the operation of the microcomputer in case of an emergency; A current sensing unit (h) for detecting whether the minimum current and the maximum current are operating within a set current range during charging, and a voltage sensing unit for sensing the voltage at the output terminal according to the control signal of the microcomputer (b) ( I), the equalizing unit (car) for supplying the terminal current for a predetermined time when the predetermined constant voltage is maintained during charging by the control signal of the microcomputer (i), and the relay driving by the control signal of the microcomputer (a) A pulse width modulation drive output unit for outputting a pulse width modulated signal for outputting the modulated signal and a pulse width modulated signal output by the control signal of the microcomputer (E) and a display for displaying abnormality by the control signal of the microcomputer (a) and the charging unit (wave) for charging current and voltage according to the drive signal output from the pulse width modulation drive output unit (ta). Switching charger, characterized in that configured as a negative (lower). According to claim 1, The charging unit (wave) is a micro-switch (MC1) and the relay (supply and cut off the voltage (RST) input from the output unit power input terminal (AC) while the switch (MC1-S) on and off The first switching unit A composed of RY1, the micro switch MC2 for switching the AC voltage input through the first switching unit A, and the second switching unit B composed of the relay RY2. ), A bridge diode BD1 composed of diodes D1-D6 rectifying the AC voltage input through the second switching unit B, and a voltage output from the bridge diode BD1. And an electrolytic capacitor C1 (C2) charged through the switch MC2-S, and a switching element that receives a pulse width modulated signal from the microcomputer A and outputs a square wave signal while alternately switching driving ( IGBT1 (IGBT2) and the signal voltage output from the switching elements IGBT1 (IGBT2) are converted. Is a transformer (T1), a diode (D7) (D8) for full-wave rectifying the signal output from the transformer (T1), and the coil (L) for smoothing the rectified voltage in the diode (D7) (D8) and . By connecting a current transformer (CT) for sensing the current of the voltage smoothed by the coil (L), and a storage battery (BAT) for charging a direct current to the output terminal of the current transformer (CT) through a resistor (R2) capacitor (C3) Switching charging device, characterized in that.