KR20090103132A - Balenced charging apparatus of ultracapacitors and balenced charging method thereof - Google Patents

Abstract

PURPOSE: An ultra capacitor balanced charging device and a charging method thereof are provided to increase a life of a capacitor assembly and offer a stable charging/discharging characteristic. CONSTITUTION: A capacitor assembly(101) includes a plurality of ultra capacitors(100) which are serially connected. A switching element(102) is connected in parallel to an ultra capacitor to bypass the current selectively. An individual voltage measuring unit(103) measures the voltage of both ends of each ultra capacitor. A reference voltage setting unit(105) sets the reference voltage by calculating an average voltage of the capacitor assembly. A controller(104) compares the reference voltage with the measured result of the individual voltage measuring unit. If the measured result exceeds the reference voltage, the controller bypasses the current flowing in the ultra capacitor by driving a switching element corresponding to the ultra capacitor.

Description

Balanced charging apparatus of ultracapacitors and balenced charging method

The present invention relates to a capacitor charging device and a charging method thereof, and more particularly, to an ultracapacitor equal charging device capable of equally charging a plurality of ultracapacitors connected in series with each other, and a charging method thereof.

Typically, the charging device is configured to include a capacitor assembly (capacitor assembly) in which a plurality of charging capacitors are connected in series with each other so as to obtain the required output voltage, a circuit diagram for supplying the appropriate power to each capacitor and control the charge / discharge mode It is provided. Such a conventional charging device adjusts DC power supplied from a predetermined power supply to an appropriate voltage and current, and then applies them to respective capacitors. In the event of overcharge or abnormal current, the controller collectively powers the capacitor assembly. It is separated from the supply and operated to stop charging.

However, such a charging device performs a charging stop operation collectively without considering the charging characteristics of the individual capacitors constituting the capacitor assembly, so that a specific capacitor is not overcharged compared to other capacitors or, unlike other capacitors, is not fully charged. There is a vulnerability in which a capacitor may be present in which the power supply is interrupted. Such unbalanced charging may adversely affect the life of the capacitor, resulting in problems such as a decrease in the quality of the charging device, such as a reduced charging capacity or the required operating voltage is not obtained.

As an alternative to the above problems, US Patent Publication No. 2003-214267, Japanese Patent Publication No. 2005-86900, and the like disclose a technique for individually controlling the charging of each capacitor using a balancing circuit. The conventional charging device using the balancing circuit as described above is configured to stop the charging when the reference value is reached by comparing the voltage measurement values across each capacitor with respect to the voltage reference value which is fixed in advance.

However, according to the above-mentioned patents, even when the characteristic of the entire capacitor assembly is changed due to the change in the operation characteristics of a specific capacitor, charging control is performed using the fixed voltage reference value as it is, resulting in uneven charging of the capacitors. There is a fear that it may occur.

The present invention was devised in consideration of the above problems, and provides an ultra-capacitor equal charging device capable of equally charging each ultracapacitor of the capacitor assembly by providing a bypass reference voltage reflecting actual characteristics of the capacitor assembly. The purpose is to provide.

In order to achieve the above object, the ultracapacitor equal charging device according to the present invention is configured to measure the voltage of the entire capacitor assembly and use it as a bypass reference voltage.

That is, the ultracapacitor equal charging device according to the present invention includes a capacitor assembly having a plurality of ultracapacitors connected in series; A switching element connected in parallel to said ultra capacitor to selectively bypass current for each ultra capacitor; An individual voltage measuring unit connected in parallel with each ultra capacitor to measure a voltage across each ultra capacitor; A reference voltage setting unit configured to set a reference voltage by calculating an average voltage of the entire capacitor assembly; And comparing the measurement result of the individual voltage measuring unit with the reference voltage and, when the measurement result of the individual voltage measuring unit exceeds the reference voltage, drives a switching element corresponding to the corresponding ultracapacitor to bypass current flowing through the ultracapacitor. The control unit;

Preferably, the reference voltage setting unit calculates the average voltage by dividing the measured voltage across the capacitor assembly by the number of the ultracapacitors.

The ultra capacitor is preferably a super capacitor, an electric double layer capacitor, or a hybrid electric double layer capacitor.

The switching element may include a MOS FET having a source terminal and a drain terminal connected to both ends of the ultracapacitor, and a gate-source voltage controlled by the controller. Can be employed.

Alternatively, as the switching element, a bipolar transistor (BJT) having an emitter terminal and a collector terminal respectively connected to both ends of the ultra capacitor, and having a base current controlled by the controller, may be employed.

According to another aspect of the invention, the steps of measuring the voltage across the capacitor assembly having a plurality of ultra capacitors connected in series; Calculating an average voltage of the entire capacitor assembly and setting a reference voltage using the average voltage; Measuring the voltage across each ultra capacitor; And comparing the reference voltage with a voltage measurement value across the ultra capacitor, and bypassing current flowing through the ultra capacitor when the voltage measurement value exceeds the reference voltage. do.

According to the present invention, by setting a reference voltage according to the total voltage of the capacitor assembly to perform the bypass operation for the current flowing in the ultra capacitor, it is possible to equally charge each ultra capacitor by reflecting the actual operating characteristics of the capacitor assembly. There is this.

Therefore, not only the life of the capacitor assembly can be improved, but also stable charge / discharge characteristics can be provided for the electronic products to be powered.

The following drawings, which are attached to this specification, illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention serve to further understand the technical spirit of the present invention, the present invention includes matters described in such drawings. It should not be construed as limited to.

1 is a block diagram showing the configuration of an ultracapacitor equal charging device according to a preferred embodiment of the present invention.

FIG. 2 is a circuit diagram schematically illustrating an example in which a MOS FET is employed as the switching element in FIG. 1.

FIG. 3 is a circuit diagram schematically illustrating an example in which BJT is employed as the switching element in FIG. 1.

4 is a flowchart illustrating an ultracapacitor equal charging method according to a preferred embodiment of the present invention.

<Description of main reference numerals in the drawings>

100: ultracapacitor 101: capacitor assembly

102: switching element 103: individual voltage measuring unit

104: control unit 105: reference voltage setting unit

107: voltage supply 108: current supply

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

1 is a block diagram showing the configuration of an ultracapacitor equal charging device according to a preferred embodiment of the present invention.

Referring to FIG. 1, an ultracapacitor equal charging device includes a capacitor assembly 101 including a plurality of ultracapacitors 100 for storing electrical energy provided from a predetermined power supply (not shown), and each ultracapacitor ( A plurality of switching elements 102 connected in parallel with respect to 100, a plurality of individual voltage measuring units 103 measuring voltages across the respective ultra capacitors 100, and reference voltages according to the total voltages of the capacitor assemblies 101. A reference voltage setting unit 105 for setting a voltage and a control unit 104 for bypassing a current by driving the corresponding switching element 102 when the voltage measurement value of the individual voltage measuring unit 103 exceeds the reference voltage. .

The capacitor assembly 101 has ultracapacitors 100 connected in series to provide the required output voltage and charge capacity. The ultracapacitor 100 is an energy storage device that can compensate for the low energy density of a conventional capacitor and the low output characteristics of a secondary battery. The ultracapacitor 100 has a low resistance characteristic, a wide operating temperature range of about -40 ° C to 70 ° C, and excellent long-term reliability. Has the characteristics of. The ultracapacitor 100 is preferably a product commercialized in the form of a super capacitor, an electric double layer capacitor or a hybrid electric double layer capacitor.

The switching elements 102 are connected in parallel to each of the ultracapacitors 100, and selectively adjust the charging voltage across the ultracapacitors 100 by bypassing current flowing through the ultracapacitors 100. . As the switching element 102, a semiconductor switch such as a MOS field effect transistor (MOS FET) or a bipolar transistor (BJT) is preferably used.

2 schematically shows an example in which a MOS field effect transistor (MOS FET) is employed as the switching element 102. In this case, the source terminal and the drain terminal of the MOS FET are connected to both ends of the ultracapacitor 100, and selectively supply the gate-source voltage from the voltage supply unit 107. It is driven on / off to bypass the current flowing in the ultracapacitor 100. In addition, it is preferable that the stabilizing resistor 106 is connected to the switching element 102 in series to prevent an overcurrent from flowing in the circuit during the bypass operation.

3 schematically shows an example in which a bipolar transistor BJT is employed as the switching element 102. In this case, the emitter and collector terminals of the bipolar transistor BJT are connected to both ends of the ultracapacitor 100, and are selectively supplied with a base current from the current supply unit 108. It is driven off to bypass the current flowing in the ultracapacitor 100.

 The individual voltage measuring unit 103 is connected in parallel to each of the ultracapacitors 100 to measure voltages across the corresponding ultracapacitors 100. As a technical configuration for measuring an individual voltage of the ultracapacitor 100, various types of known voltage measuring circuits may be adopted.

The reference voltage setting unit 105 calculates an average voltage of the entire capacitor assembly 101 to set a reference voltage for current bypass. To this end, the reference voltage setting unit 105 is connected to both ends of the capacitor assembly 101 to measure the total voltage of the capacitor assembly 101, and divides the measured voltage by the number of ultracapacitors 100 to calculate the average voltage. do. As a technical configuration for measuring the total voltage of the capacitor assembly 101, various types of known voltage measuring circuits can be adopted.

The control unit 104 compares the reference voltage set by the reference voltage setting unit 105 with the measurement results of the individual voltage measuring unit 103, and when the measurement result of the individual voltage measuring unit 103 exceeds the reference voltage. The switching element 102 corresponding to the ultra capacitor 100 is driven to bypass some or all of the current flowing through the ultra capacitor 100.

If the switching element 102 is a MOS FET, the control unit 104 controls the voltage supply unit 107 to drive the switching element 102 on and off, and the switching element 102 is bipolar. In the case of the transistor BJT, the current supply unit 108 is controlled to drive the switching element 102 on / off.

The reference voltage setting unit 105 and the control unit 104 may be included in the same controller module, but the present invention is not limited thereto.

4 illustrates an ultracapacitor equal charging method which may be performed by an ultracapacitor equal charging device having the above configuration.

Referring to FIG. 4, the present invention sets the reference voltage according to the total voltage of the capacitor assembly 101, measures the voltage across both of the ultracapacitors 100, and compares the reference voltage with the reference voltage to thereby charge the ultracapacitor 100. Individually controlled.

That is, first measuring the voltage across the capacitor assembly 101 to measure the total voltage, and then calculates the average voltage to set the reference voltage (steps S100 and S110), and then configure the capacitor assembly 101 The voltage across the respective ultracapacitors 100 is measured and compared with the reference voltage (steps S120 and S130).

In step S110, the total voltage of the capacitor assembly 101 is connected to both ends of the capacitor assembly 101, and the average voltage is calculated by dividing the measured voltage by the number of ultracapacitors 100.

In operation S130, it is determined whether the voltage measurement value across each ultra capacitor 100 exceeds the reference voltage. The voltage across each ultracapacitor 100 is measured by an individual voltage measurement unit 103 connected in parallel to each ultracapacitor 100.

As a result of the determination in step S130, when the voltage measurement value is less than the reference voltage, the charging mode for the ultra capacitor 100 is maintained (step S140), and when the voltage measurement value is greater than or equal to the reference voltage, the current flowing through the ultra capacitor 100 is determined. The bypassing process is performed (step S150).

For the processing of steps S140 and S150, a switching element 102 is connected in parallel to each ultra capacitor 100 constituting the capacitor assembly 101. Therefore, in step S140, the charging mode may be maintained by keeping the switching element 102 in an off state, and in step S150, the corresponding ultracapacitor 100 is turned on by switching the switching element 102 in an on state. The current flowing through the N-B may be bypassed toward the switching element 102. After the bypass operation, when the voltage of the corresponding ultracapacitor 100 approaches the average value, the control to turn off the switching element 102 is performed again, and the above operations are repeated for the corresponding ultracapacitors 100. The capacitor assembly 101 performs charge / discharge evenly.

As described above, the present invention maintains the charge voltage and the charge amount of each ultra capacitor 100 evenly by performing individual charge control according to the total voltage of the capacitor assembly 101 and the individual voltage state of each ultra capacitor 100. Can be.

Although the present invention has been described above by means of limited embodiments and drawings, the present invention is not limited thereto and will be described below by the person skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of the claims.

Claims (8)

A capacitor assembly having a plurality of ultra capacitors connected in series; A switching element connected in parallel to said ultra capacitor to selectively bypass current for each ultra capacitor; An individual voltage measuring unit connected in parallel with each ultra capacitor to measure a voltage across each ultra capacitor; A reference voltage setting unit configured to set a reference voltage by calculating an average voltage of the entire capacitor assembly; And The measurement result of the individual voltage measuring unit and the reference voltage are compared, and when the measurement result of the individual voltage measuring unit exceeds the reference voltage, the switching element corresponding to the corresponding ultra capacitor is driven to bypass the current flowing in the ultra capacitor. Ultracapacitor equal charging device comprising a control unit. The method of claim 1, And the reference voltage setting unit calculates the average voltage by dividing the measured voltage across the capacitor assembly by the number of the ultracapacitors. The method according to claim 1 or 2, The ultracapacitor is a supercapacitor, an electric double layer capacitor or a hybrid electric capacitor, characterized in that the hybrid electric double layer capacitor. The method according to claim 1 or 2, The switching element is an ultracapacitor equal charging, characterized in that the source terminal and the drain terminal are connected to both ends of the ultracapacitor, the MOS field effect transistor (MOS FET) is controlled by the control unit the gate-source voltage. Device. The method according to claim 1 or 2, The switching element is an equalizer charging device, characterized in that the bipolar transistor (BJT) is connected to the emitter terminal and the collector terminal, respectively, and the base current is controlled by the control unit, both ends of the ultra capacitor. Measuring a voltage across the capacitor assembly having a plurality of ultracapacitors connected in series; Calculating an average voltage of the entire capacitor assembly and setting a reference voltage using the average voltage; Measuring the voltage across each ultra capacitor; And Comparing the reference voltage with a voltage measurement value across the ultra capacitor, and bypassing a current flowing through the corresponding ultra capacitor when the voltage measurement value exceeds the reference voltage. The method of claim 6, Ultracapacitor equal charging method characterized in that the average voltage of the entire capacitor assembly is calculated by dividing the voltage of the entire capacitor assembly by the number of the ultracapacitor. The method according to claim 6 or 7, The ultracapacitor equal charging method, characterized in that using a supercapacitor, an electric double layer capacitor or a hybrid electric double layer capacitor.