KR20150087694A - Battery charging apparatus using ultra capacitor - Google Patents

Abstract

The present invention provides a battery charging apparatus using an ultra capacitor. It performs quick charge, extends the lifespan of a battery, maximizes the lifespan of the battery, uses a current control method for preventing deterioration, charges ultra capacitors at the same time, minimizes duration time in an energy station by successive discharge, and maximize the capacity of voltage increase in a voltage increasing prat by using an intermediate tap method. A battery charging apparatus using an ultra capacitor according to the present invention, includes a quick charge switch part for quick charge; an ultra capacitor which is connected in parallel to the quick charge switch part; a slow charge switch part which is connected in parallel to the ultra capacitor; and a slow charge part which is connected in parallel to the slow charge switch part.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a battery charger using an ultracapacitor,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a battery charging apparatus, and more particularly, to an apparatus for charging a battery using an ultracapacitor.

Due to the depletion of fossil fuels, electric vehicles using batteries have been developed and commercialized in earnest. However, unlike a general vehicle using fossil fuel (gasoline, light oil, etc.), there is a problem that it takes a lot of time to charge the electric vehicle.

That is, the battery requires 4 to 10 hours for the conventional charging method, and at least 30 minutes for the rapid charging method. Particularly, when the battery is rapidly charged, the life of the battery is shortened due to the chemical characteristics of the battery. This is also applicable to an electric forklift charger, and the electric forklift charger generally has both a normal charging and a rapid charging mode. Here, the normal charging mode is a constant current charging mode in which a constant current is charged until a voltage charged in the battery reaches a certain voltage, a constant current charging mode in which a constant current is charged until a current to be charged in the battery is reduced to an arbitrary current A constant voltage charging mode, and an even charging mode in which the small current is charged for a predetermined time. Also, the rapid charging mode includes a large current charging mode in which a constant current (large current) is charged into the battery within a predetermined charging time.

In the case of rapid charging as described above, various problems may occur. Firstly, when the rapid charging is continuously performed, the performance of the battery deteriorates and the life thereof is shortened. Secondly, when the battery is fully charged, The battery may be damaged due to an overvoltage generated in the battery. Thirdly, if the battery is rapidly discharged in a fully discharged state, there is a high possibility that the battery is not fully charged. Fourthly, if rapid charging is performed immediately after completion of rapid charging, And is destroyed.

In order to solve such a problem, in a charging method for an electric forklift charger disclosed in Japanese Patent Application Laid-Open No. 2007-0072788, a high-voltage three-phase AC power source is connected to an external three-phase AC input means through a connector, A battery charging device including a transformer for performing a primary conversion to a three-phase AC power source and a three-phase rectifying diode for converting an AC power source to a DC power source; A charger including a battery and a supercapacitor which are charged by switching a power source of the battery charger and supplying a charging voltage and a current from the battery charger; And a DC / DC converter for controlling the voltage and current charged in the charger from the battery charging device and for converting the voltage so as to supply the voltage and current charged in the charger to the various electric loads of the forklift, A first step of limiting the number of consecutive rapid charging through counting during a rapid charging mode operation; A second step of switching to a normal charging mode when a charging voltage of the battery exceeds a reference voltage during rapid charging of the battery; And a third step of switching to a normal charging mode when the battery is not fully charged after completion of rapid charging. When the count value is smaller than a certain reference number, the charging current mode is advanced. When the count value reaches an arbitrary reference number If it is bigger, it should be proceeded with the normal charging method.

However, this type of charging method is not suitable for the case where the charging must be quickly terminated and moved since the charging method is forcibly controlled to proceed to the normal charging method after the rapid charging is continuously performed for a predetermined number of times or more.

Published patent application 2012-0072788 Charging method for electric forklift Charging method

The present invention provides a battery charging apparatus using an ultracapacitor capable of achieving long battery life while performing rapid charging.

In addition, the present invention provides a battery charging apparatus using an ultracapacitor that utilizes a current control method that can prevent performance degradation while maximizing the life of the battery.

In addition, the present invention provides a battery charging apparatus using an ultracapacitor that can minimize the time that a vehicle stays in a charging station by simultaneously charging a plurality of ultracapacitors and sequentially discharging the batteries.

In addition, the present invention provides a battery charging apparatus using an ultracapacitor that can maximize the step-up capability of the step-up unit by using an intermediate tap method.

An apparatus for charging a battery using an ultracapacitor according to the present invention includes: a rapid charging switch unit for rapid charging; An ultracapacitor coupled in parallel to the rapid charge switch unit; A slow charge switch unit connected in parallel to the ultracapacitor; And a slow charge section connected in parallel to the full charge switch section.

Preferably, the voltage step-up unit applies a three-phase commercial voltage to step up the voltage to a predetermined voltage. And a rectifying unit for rectifying the AC voltage output from the voltage-up unit to a DC voltage of a predetermined level.

Preferably, the quick charge switch section includes a plurality of quick charge switches that are turned on or off simultaneously or sequentially.

Preferably, when the charging of the ultracapacitor is completed, the plurality of rapid charging switches are all turned off.

Preferably, the full charge switch portion includes a plurality of full charge switches, the plurality of full charge switches are the same number as the plurality of the full charge switches, and the plurality of the full charge switches are selectively switched.

Preferably, the charging current controller includes: the charging current controller includes: a slow charging voltage detector connected in parallel with the fast charging unit; A switching element disposed between the slow charge switch section and the slow charge section; A comparator for comparing a battery charging voltage applied to the charging voltage detector to a predetermined reference voltage; And a control switching element for switching in accordance with an output of the comparator, wherein the switching element is controlled at an output of the control switching element.

Preferably, the switching device is any one of an IGBT, an FET, and a BJT, an IGBT connected in parallel, a FET connected in parallel, or a BJT connected in parallel.

Preferably, the slowly charged voltage detector further includes a constant temperature coefficient element.

The present invention is capable of achieving long life of a battery while performing rapid charging, and it is possible to prevent deterioration of performance while maximizing battery life, and simultaneously charging a plurality of ultracapacitors and discharging them sequentially, So that it is possible to maximize the step-up capability of the step-up part by using the intermediate tap method. At this time, the charging time is only a few seconds (3 ~ 15 seconds). That is, in the ultracapacitor charged in the shortest time, the battery is charged slowly using the voltage and current regulating circuit.

1 is an overall circuit diagram of a battery charging apparatus according to a first embodiment of the present invention;
FIG. 2 is a specific circuit diagram of a current controller in a battery charging device according to a second embodiment of the present invention, and FIG.
3 is a specific circuit diagram of a current controller in a battery charging device according to a third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

FIG. 1 is an overall circuit diagram of a battery charging apparatus according to a first embodiment of the present invention. The battery charging apparatus includes a voltage booster 110, a rectifier 120, a rapid charging switch 130, a rapid charging unit 140, 150, a charge current control unit 160, and a fast charge unit 170.

The step-up unit 110 applies a three-phase commercial voltage to step up to a predetermined voltage. For example, 220 volts is applied and the voltage is increased to 800 volts.

The rectifying unit 120 rectifies an AC voltage boosted to 800 volts around the center tap to a DC voltage.

The quick-charge switch section 130 includes a plurality of mechanical fast-charge switches 131, 132, ..., and is simultaneously closed or opened. That is, a plurality of mechanical rapid-charge switches are simultaneously or sequentially closed to charge the ultralcapacitor at the subsequent stage, and when the charging of the ultracapacitor is completed, a plurality of mechanical rapid-charge switches are opened simultaneously or sequentially.

The rapid charging section 140 includes an ultracapacitor coupled in parallel at the rear end of each mechanical rapid charge switch. Unlike conventional capacitors, ultracapacitors have capacities of several Farads [F].

The full charge switch unit 150 is connected in parallel to the rear end of the rapid charging unit 140, and is selectively closed or opened. The fast charging switch unit 150 is selectively closed in the state where the rapid charging switch unit 130 is opened to charge the final charging unit 170 at the rear stage.

The charging current controller 160 receives the battery charging voltage applied to the battery charging voltage detector (variable resistor R2) at the inverting terminal and receives the zener voltage applied to the zener diodes VZD1 and VZD2 to the non- A control switching element TR1 for switching in accordance with the output of the comparator and a control switching element TR1 disposed on the path between the rapid charging part 140 and the fully charged part 170, And a controlled switching element TR2 (IGBT). Here, by adjusting the variable resistor R2, the magnitude of the current passing through the switching element TR2 can be adjusted.

Meanwhile, according to another embodiment of the present invention, the switching element TR2 may be replaced with an FET instead of an IGBT, or a BJT. Also, according to another embodiment of the present invention, the switching device TR2 may be replaced with an IGBT, a parallel-connected FET, and a parallel-connected BJT connected in parallel so as to improve the magnitude of the current that can pass therethrough.

A lithium ion battery, a lithium iron phosphate battery, a nickel hydride battery, or a nickel cadmium battery may be used as the battery of the fast charging unit 170.

The operation of the battery charging apparatus according to the first embodiment of the present invention will now be described.

First, all the switches in the rapid charging switch unit 130 are closed simultaneously or sequentially in a state where the full charging switch unit 160 is opened, thereby charging the ultracapacitor as the rapid charging unit 140 within several seconds to several tens of seconds. When the charging of the ultracapacitor is completed, all the switches in the rapid charging switch unit 130 are opened simultaneously or sequentially, and at least one of the plurality of slow charging switches in the slow charging switch unit 150 is selectively closed, (170) for a few minutes to several hours. For example, when the first full charge switch 151 is closed and the slow charging from the first ultracapacitor UC1 to the battery 170 is completed, the first full charge switch 151 is opened and the second full charge switch 152 is opened. So that the second ultracapacitor UC2 can be charged slowly with the battery 170.

Meanwhile, the battery charging apparatus according to an embodiment of the present invention can be mounted inside a vehicle using electricity as an energy source. In addition, the battery charging apparatus according to another embodiment of the present invention may be mounted inside a vehicle that uses electricity as an energy source, including a configuration other than a charging unit and a rectifying unit. Accordingly, while the charging time is greatly reduced, rapid charging to the battery is prevented, and the life of the battery can be increased. That is, if the driving motor is in a stopped state during the operation of the vehicle, the ultrafast capacitor is charged to the battery slowly.

FIG. 2 is a specific circuit diagram of a current control unit in a battery charging apparatus according to a second embodiment of the present invention. Most of the configuration is the same as in FIG. 1 except that the battery charge voltage detecting unit further includes a positive temperature coefficient element . The combined resistance value of the resistor R23 connected in series and the constant temperature coefficient element becomes small because the resistance value becomes small when the air temperature becomes low due to the characteristics of the constant temperature coefficient element and therefore the reference voltage applied to the inverting terminal of the comparator is low . On the other hand, when the external temperature is lowered, the battery is actively discharged. Therefore, when the reference voltage applied to the inverting terminal of the comparator is lowered, it is necessary to control so that a larger current flows through the switching device IGBT even if the voltage across the switching device IGBT is the same.

FIG. 3 is a specific circuit diagram of the current control unit in the battery charging apparatus according to the third embodiment of the present invention. Most of the configuration is the same as in FIG. 2 except that a plurality of control switching elements TR1 and TR2 are used to perform a slow charge You can control it more precisely.

As described above, the technical ideas described in the embodiments of the present invention can be implemented independently of each other, or can be implemented in combination with each other. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not to be limited to the details thereof and that various changes and modifications will be apparent to those skilled in the art. Various modifications and variations are possible within the scope of the appended claims.

110:
120: rectification part
130: rapid charge switch section
140:
150: Slow charge switch section
160: charge current control section
170:

Claims (9)

A rapid charging switch section for rapid charging;
An ultracapacitor coupled in parallel to the rapid charge switch unit;
A slow charge switch unit connected in parallel to the ultracapacitor; And
And a fast charging part
And a battery charger using the ultracapacitor.
The method according to claim 1,
A step-up unit for applying a three-phase commercial voltage and stepping up the voltage to a predetermined voltage; And
A rectifying unit for rectifying the alternating-current voltage output from the voltage-boosting unit to a direct-
Further comprising a capacitor connected to the battery.
3. The method according to claim 1 or 2,
Wherein the rapid charging switch unit includes a plurality of rapid charging switches that are turned on or off simultaneously or sequentially.
The method of claim 3,
Wherein when the charging of the ultracapacitor is completed, the plurality of rapid charging switches are all turned off.
5. The method of claim 4,
Wherein the slow charge switch section includes a plurality of slow charge switches, the plurality of slow charge switches are the same number as the plurality of rapid charge switches, and the plurality of slow charge switches are selectively switched. Battery charger.
6. The charge pump circuit according to claim 5,
A slow charge voltage detector connected in parallel to the slow charge section;
A switching element disposed between the slow charge switch section and the slow charge section;
A comparator for comparing a battery charging voltage applied to the charging voltage detector to a predetermined reference voltage; And
And a control switching element for switching in accordance with the output of the comparator,
Wherein the switching element is controlled by an output of the control switching element.
The method according to claim 6,
Wherein the switching element is any one of an IGBT, an FET, and a BJT, or an IGBT connected in parallel, a parallel connected FET, or a BJT connected in parallel.
The method according to claim 6,
Wherein the fully charged voltage detecting unit further includes a positive temperature coefficient element.
An electric vehicle mounted with a battery charging device using the ultra-capacitor according to claim 1 or 2.

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