CN103001297B - Series capacitor bank resonant type voltage balance charging method and system - Google Patents
Series capacitor bank resonant type voltage balance charging method and system Download PDFInfo
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- CN103001297B CN103001297B CN201210587980.0A CN201210587980A CN103001297B CN 103001297 B CN103001297 B CN 103001297B CN 201210587980 A CN201210587980 A CN 201210587980A CN 103001297 B CN103001297 B CN 103001297B
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Abstract
The invention discloses a series capacitor bank resonant type voltage balance charging method and a system. The method includes that a direct current charging power supply is used to charge a series capacitor bank, a voltage balance unit which is in a parallel connection with each capacitor monomer in the series capacitor bank comprises voltage reducing buffering and electric energy releasing modules which share an inductor/capacitor (LC) series connection structure, and capacitors are respectively in a parallel connection between source electrodes and drain electrodes of a buffer switch G1 and a release switch G2 which are complemented and connected. The capacitor monomers with slowest increasing terminal voltage are connected with a negative electrode of the direct current charging power supply. The system comprises the series capacitor bank and the direct current charging power supply, two ends of each capacitor monomer are in the parallel connection with the voltage balance units, and each voltage balance unit comprises a voltage detecting unit, a pulse modulation unit, a complementary driving unit, the release switch, the buffer switch and an LC series energy storage unit. By means of the series capacitor bank resonant type voltage balance charging method and the system, the problem of unbalance terminal voltage of the capacitor monomers in the process of capacitor series charging can be prevented, the energy consumption is low, and the structural expandability is high.
Description
Technical field
The present invention relates to a kind of series capacitor bank resonant voltage balanced charging method and system thereof.
Background technology
Super capacitor is a kind of novel energy-storing element that utilizes electric double layer principle to realize, monomer capacity not only can reach tens thousand of farads, have simultaneously have extended cycle life, the advantage such as temperature range is wide, the speed that discharges and recharges is fast, environmental protection, because the rated voltage of super capacitor monomer is lower, therefore need to be by multiple monomer series-connected, to meet the on-the-spot needs of capacity and operating voltage grade in actual application.But owing to producing the restriction of material and manufacturing process etc., even the on all four monomer of nominal parameters, generally can there is significant difference in the parameters such as its actual equivalent series internal resistance, capacity, charge-discharge velocity, therefore in many super capacitor series connection use procedures, individual terminal voltage can present typical lack of uniformity, this phenomenon has not only reduced the storage efficiency of energy, may cause the generation that overcharges of monomer simultaneously, has had a strong impact on useful life and the reliability of super capacitor.
Summary of the invention
The object of the invention is to overcome deficiency of the prior art, provide a kind of useful life charging voltage equilibrium, that can extend capacitor monomer that keeps each capacitor monomer in series capacitor bank, energy-saving effect significant series capacitor bank resonant voltage balanced charging method and system thereof.
Object of the present invention is achieved by following technical proposals:
Described method comprises that use DC charging power supply charges to series capacitor bank; Each capacitor monomer shunt voltage balanced unit in series capacitor bank; In electric voltage equalization unit:
(1) there is the step-down buffer module of RLC series circuit: be made up of inductor L, capacitor C in buffer switch G1 and LC series connection accumulation unit, this RLC series circuit works in underdamping state, and wherein R is the equivalent resistance summation of G1, L and C;
(2) there is the electric energy release module of RLC series circuit: formed by inductor L, capacitor C in release-push G2 and LC series connection accumulation unit, RLC series circuit works in underdamping state, wherein R is the equivalent resistance summation of G2, L and C, the electrical characteristic of G2 is identical with G1, and equivalent internal resistance also equates;
(3) buffer switch G1 and release-push G2 are operated in complementary conducting state, and switch periods and duty ratio are consistent with the resonance frequency of RLC series circuit;
(4) shunt capacitance respectively between the source electrode of buffer switch G1 and release-push G2 and drain electrode, in conjunction with the resonance characteristic of place RLC series circuit separately, makes buffer switch G1 and release-push G2 be operated in soft on off state, reduction switch energy loss;
(5) in the time that the terminal voltage of capacitor monomer exceedes given threshold values, voltage detection unit output high level in electric voltage equalization unit, pulse modulation unit output in electric voltage equalization unit has the square wave of some cycles and duty ratio, by complementary drive unit drives buffer switch G1 and the complementary conducting of release-push G2 or cut-off; When the terminal voltage of capacitor monomer is during lower than given threshold values, voltage detection unit output low level, pulse modulation unit is output low level signal always, and now buffer switch G1 is in cut-off state, and release-push G2 is in conducting state.
The slowest capacitor monomer of terminal voltage growth is connected to the negative pole of DC charging power supply, the voltage detection unit output low level always of the electric voltage equalization unit of this grade of capacitor monomer parallel connection, pulse modulation unit is output low level signal always, now G1 ends always, G2 is conducting always, can further reduce the energy consumption of whole electric voltage equalization charging system.
Described system comprises series capacitor bank and DC charging power supply; The two ends shunt voltage balanced unit of the each capacitor monomer in series capacitor bank; Described electric voltage equalization unit comprises voltage detection unit, pulse modulation unit, complementary drive unit, buffer switch, release-push, LC series connection accumulation unit; The input of voltage detection unit is connected to the two ends of capacitor monomer, the output of voltage detection unit connects pulse modulation unit, pulse modulation unit connects complementary drive unit, two outputs of complementary drive unit connect respectively buffer switch and release-push, LC series connection accumulation unit is connected with the gentle pass of washing open of release-push, forms respectively RLC step-down release circuit and RLC electrical power storage circuit.
Described voltage detection unit adopts BL8506 integrated chip; Complementary drive unit adopts TPS28225 integrated chip; Buffer switch G1 and release-push G2 all adopt Mosfet switching tube.
The resonance cycle, electric current and voltage zero-cross characteristic and the electrical characteristic that determine according to corresponding RLC series circuit, an electric capacity in parallel between the source electrode of each Mosfet switching tube and drain electrode, guarantee that Mosfet switching tube is operated in soft on off state, reduce the switching loss of Mosfet switching tube.
Compared with prior art, the present invention has the following advantages: can keep the charging voltage equilibrium of each capacitor monomer in series capacitor bank, can effectively extend the useful life of capacitor monomer, energy loss is low, energy-saving effect is remarkable, and structure extensibility is strong.
Brief description of the drawings
Fig. 1 is system one embodiment electrical principle block diagram of the present invention;
Fig. 2 is the main circuit diagram of 1 electric voltage equalization unit one embodiment;
In figure: 1-capacitor monomer, 2-electric voltage equalization unit..
Embodiment
Below in conjunction with drawings and Examples, the invention will be further described:
Described method comprises that use DC charging power supply charges to series capacitor bank; Each capacitor monomer 1 shunt voltage balanced unit in series capacitor bank; In electric voltage equalization unit:
(1) there is the step-down buffer module of RLC series circuit: be made up of inductor L, capacitor C in buffer switch G1 and LC series connection accumulation unit, this RLC series circuit works in underdamping state, and wherein R is the equivalent resistance summation of G1, L and C;
(2) there is the electric energy release module of RLC series circuit: formed by inductor L, capacitor C in release-push G2 and LC series connection accumulation unit, RLC series circuit works in underdamping state, wherein R is the equivalent resistance summation of G2, L and C, the electrical characteristic of G2 is identical with G1, and equivalent internal resistance also equates;
(3) buffer switch G1 and release-push G2 are operated in complementary conducting state, and switch periods and duty ratio are consistent with the resonance frequency of RLC series circuit;
(4) shunt capacitance respectively between the source electrode of buffer switch G1 and release-push G2 and drain electrode, in conjunction with the resonance characteristic of place RLC series circuit separately, makes buffer switch G1 and release-push G2 be operated in soft on off state, reduction switch energy loss;
(5) in the time that the terminal voltage of capacitor monomer 1 exceedes given threshold values, voltage detection unit output high level in electric voltage equalization unit, pulse modulation unit output in electric voltage equalization unit has the square wave of some cycles and duty ratio, by complementary drive unit drives buffer switch G1 and the complementary conducting of release-push G2 or cut-off; When the terminal voltage of capacitor monomer (1) is during lower than given threshold values, voltage detection unit output low level, pulse modulation unit is output low level signal always, and now buffer switch G1 is in cut-off state, and release-push G2 is in conducting state.
The slowest capacitor monomer 1 of terminal voltage growth is connected to the negative pole of DC charging power supply, the voltage detection unit output low level always of the electric voltage equalization unit of this grade of capacitor monomer 1 parallel connection, pulse modulation unit is output low level signal always, now G1 ends always, G2 is conducting always, can further reduce the energy consumption of whole electric voltage equalization charging system.
Described system comprises series capacitor bank and DC charging power supply; The two ends shunt voltage balanced unit 2 of the each capacitor monomer 1 in series capacitor bank; Described electric voltage equalization unit 2 comprises voltage detection unit, pulse modulation unit, complementary drive unit, buffer switch, release-push, LC series connection accumulation unit; The input of voltage detection unit is connected to the two ends of capacitor monomer 1, the output of voltage detection unit connects pulse modulation unit, pulse modulation unit connects complementary drive unit, two outputs of complementary drive unit connect respectively buffer switch and release-push, LC series connection accumulation unit is connected with the gentle pass of washing open of release-push, forms respectively RLC step-down release circuit and RLC electrical power storage circuit.
Described voltage detection unit adopts BL8506 integrated chip; Complementary drive unit adopts TPS28225 integrated chip; Buffer switch G1 and release-push G2 all adopt Mosfet switching tube.
The resonance cycle, electric current and voltage zero-cross characteristic and the electrical characteristic that determine according to corresponding RLC series circuit, an electric capacity in parallel between the source electrode of each Mosfet switching tube and drain electrode, guarantee that Mosfet switching tube is operated in soft on off state, reduce the switching loss of Mosfet switching tube.
The embodiment of system:
Referring to accompanying drawing 1, described system is mainly made up of series capacitor bank, DC charging power supply and electric voltage equalization unit 2; The two ends shunt voltage balanced unit 2 of the each capacitor monomer 1 in series capacitor bank; Described electric voltage equalization unit 2 comprises the voltage detection unit of BL8506 integrated chip, the complementary drive unit of TPS28225 integrated chip, the buffer switch of Mosfet switching tube G1, the release-push of Mosfet switching tube G2, the LC series connection accumulation module of lc circuit; The input of voltage detection unit is connected to the two ends of capacitor monomer 1, the output of voltage detection unit the be linked in sequence pulse modulation unit of 555 integrated chips and the complementary drive unit of TPS28225 integrated chip, two outputs of complementary drive unit connect respectively G1 and G2, difference shunt capacitance C1 and C2 between the source electrode of G1 and G2 and drain electrode; LC series connection accumulation unit and G2 form the RLC release circuit that the C of LC series connection accumulation unit is discharged; LC series connection accumulation unit and G1 form the RLC buffer circuit that the C of LC series connection accumulation unit is charged.
The operation principle of system embodiment:
In process at DC charging power supply DC to series capacitor bank charging, the electric current of each capacitor monomer 1 of flowing through is identical, and due to there are differences of the individual internal resistance value of capacitor monomer 1, the voltage that each capacitor monomer 1 distributes is not identical.In the time that the voltage detection module of the BL8506 integrated chip of the electric voltage equalization unit 2 of certain grade of capacitor monomer 1 detects that its terminal voltage exceeds the threshold values of setting, the output output high level of BL8506 integrated chip, order about the oscillation module of 555 integrated chips, 555 integrated chip outputs have the control signal of characteristic frequency and duty ratio, produce switching drive signal and control the complementary conducting of G1, G2 through the complementary drive of TPS28225 integrated chip.In the time that G1 conducting G2 ends, capacitor monomer 1 is charged and the terminal voltage of capacitor monomer 1 at the corresponding levels is declined to the capacitor C in LC series connection accumulation unit by G1, L; G2 conducting when G1 cut-off, the capacitor C in LC series connection accumulation unit is by the downward series capacitor monomer electric discharge of L, G2, and the result of electric discharge is to have improved the current potential of the B end of capacitor monomer 1 at the corresponding levels, has improved the current potential of the A end of subordinate's capacitor monomer 1.Electric voltage equalization unit 2 takes full advantage of the resonance characteristic in RLC loop, and in the time of resonance current or voltage zero-cross, switching tube just completes conducting or cut-off action.Simultaneously Mosfet switching tube G1, G2 respectively capacitor C 1, C2 in parallel can effectively guarantee no-voltage by, and the small inductor L of series connection can effectively guarantee Mosfet switch tube zero current lead-through, above measure has realized soft switching function, can effectively reduce the switching loss of Mosfet switching tube, improve the system effectiveness of by-pass shunt step-down.
In addition; electric voltage equalization strategy is overvoltage protection strategy in itself; in the charging process of series capacitor bank; only close to an end in charging process or exceed given threshold values because the excessive reason of the actual parameter deviation of series capacitor monomer 1 causes certain individual terminal voltage; just can work in corresponding electric voltage equalization unit 2; in conjunction with soft switch technique, can realize the low energy consumption overvoltage step-down protection strategy of series capacitor bank simultaneously.
The present invention has not only realized the charging voltage equilibrium of series capacitor by two associated underdamping RLC series circuits, the signal sequence of cooperation driving simultaneously etc. makes switching tube be operated in soft on off state, effectively reduces switching loss and has good structure extensibility.
Claims (5)
1. a series capacitor bank resonant voltage balanced charging method, described method comprises that use DC charging power supply charges to series capacitor bank; Each capacitor monomer (1) shunt voltage balanced unit in series capacitor bank; It is characterized in that: in electric voltage equalization unit:
(1) there is the step-down buffer module of a RLC series circuit: formed by inductor L, capacitor C in buffer switch G1 and LC series connection accumulation unit, this RLC series circuit works in underdamping state, and wherein the first resistance R is the equivalent resistance summation of G1, L and C;
(2) there is the electric energy release module of the 2nd RLC series circuit: formed by inductor L, capacitor C in release-push G2 and LC series connection accumulation unit, RLC series circuit works in underdamping state, wherein the second resistance R is the equivalent resistance summation of G2, L and C, the electrical characteristic of G2 is identical with G1, and equivalent internal resistance also equates;
(3) buffer switch G1 and release-push G2 are operated in complementary conducting state, and switch periods and duty ratio are consistent with the resonance frequency of RLC series circuit;
(4) shunt capacitance respectively between the source electrode of buffer switch G1 and release-push G2 and drain electrode, in conjunction with the resonance characteristic of place RLC series circuit separately, makes buffer switch G1 and release-push G2 be operated in soft on off state, reduction switch energy loss;
(5) in the time that the terminal voltage of capacitor monomer (1) exceedes given threshold values, voltage detection unit output high level in electric voltage equalization unit, pulse modulation unit output in electric voltage equalization unit has the square wave of some cycles and duty ratio, by complementary drive unit drives buffer switch G1 and the complementary conducting of release-push G2 or cut-off; When the terminal voltage of capacitor monomer (1) is during lower than given threshold values, voltage detection unit output low level, pulse modulation unit is output low level signal always, and now buffer switch G1 is in cut-off state, and release-push G2 is in conducting state.
2. method according to claim 1, it is characterized in that: the negative pole that the slowest capacitor monomer (1) of terminal voltage growth is connected to DC charging power supply, the voltage detection unit output low level always of the electric voltage equalization unit of capacitor monomer (1) parallel connection, pulse modulation unit is output low level signal always, now buffer switch G1 ends always, release-push G2 conducting always, can further reduce the energy consumption of whole electric voltage equalization charging system.
3. a series capacitor bank resonant voltage equalizing charge system that is applicable to method described in claim 1 or 2, described system comprises series capacitor bank and DC charging power supply; The two ends shunt voltage balanced units (2) of the each capacitor monomer (1) in series capacitor bank; It is characterized in that: described electric voltage equalization unit (2) comprises voltage detection unit, pulse modulation unit, complementary drive unit, buffer switch G1, release-push G2, LC series connection accumulation unit; The input of voltage detection unit is connected to the two ends of capacitor monomer (1), the output of voltage detection unit connects pulse modulation unit, pulse modulation unit connects complementary drive unit, the first output of complementary drive unit connects buffer switch G1, the second output Connection Release switch G2, LC series connection accumulation unit is connected with release-push G2 and buffer switch G1, forms and has the electric energy release circuit of the 2nd RLC series circuit and have the step-down buffer circuit of a RLC series circuit respectively.
4. system according to claim 3, is characterized in that: described voltage detection unit adopts BL8506 integrated chip; Complementary drive unit adopts TPS28225 integrated chip; Buffer switch G1 and release-push G2 all adopt Mosfet switching tube.
5. system according to claim 4, it is characterized in that: the resonance cycle, electric current and voltage zero-cross characteristic and the electrical characteristic that determine according to corresponding RLC series circuit, an electric capacity in parallel between the source electrode of each Mosfet switching tube and drain electrode, guarantee that Mosfet switching tube is operated in soft on off state, reduce the switching loss of Mosfet switching tube.
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| CN201210587980.0A CN103001297B (en) | 2012-12-31 | 2012-12-31 | Series capacitor bank resonant type voltage balance charging method and system |
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| CN105762846A (en) * | 2014-12-15 | 2016-07-13 | 哈尔滨市三和佳美科技发展有限公司 | Series-connected farad capacitor safety charger |
| CN106405263B (en) * | 2015-07-31 | 2019-03-12 | 佛山市顺德区美的电热电器制造有限公司 | The abatement detecting method of electromagnetic heating system and its resonant capacitance, device |
| US11056896B2 (en) | 2016-10-12 | 2021-07-06 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Terminal and device |
| WO2018068461A1 (en) * | 2016-10-12 | 2018-04-19 | 广东欧珀移动通信有限公司 | Device to be charged and charging method |
| CN106532852B (en) * | 2016-12-16 | 2023-06-20 | 华南理工大学 | Battery pack equalization circuit based on LC series energy storage |
| CN106712191B (en) * | 2017-01-10 | 2023-06-20 | 华南理工大学 | Battery pack equalization circuit and method based on external energy storage unit and LC quasi-resonance |
| SG11201909124UA (en) | 2017-04-07 | 2019-11-28 | Guangdong Oppo Mobile Telecommunications Corp Ltd | Wireless charging device and method, and device to be charged |
| CN109787325B (en) | 2017-04-07 | 2023-06-27 | Oppo广东移动通信有限公司 | Wireless charging system, device and method and equipment to be charged |
| DK3462565T3 (en) | 2017-04-13 | 2021-04-26 | Guangdong Oppo Mobile Telecommunications Corp Ltd | DEVICE TO BE CHARGED AND CHARGING PROCEDURE |
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