CN102157975B - Intelligent charging system of lead acid batteries and charging method - Google Patents

Intelligent charging system of lead acid batteries and charging method Download PDF

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Publication number
CN102157975B
CN102157975B CN2011100797161A CN201110079716A CN102157975B CN 102157975 B CN102157975 B CN 102157975B CN 2011100797161 A CN2011100797161 A CN 2011100797161A CN 201110079716 A CN201110079716 A CN 201110079716A CN 102157975 B CN102157975 B CN 102157975B
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China
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lead
charging
acid battery
controller
charge
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CN2011100797161A
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Chinese (zh)
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CN102157975A (en
Inventor
王应海
李正明
潘天红
张好明
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江苏大学
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Abstract

The invention discloses an intelligent charging system of lead acid batteries and a charging method. The charging system disclosed by the invention comprises a controller and a main circuit, wherein the batteries with partial damage are maintained and precharged through the controller according to the collected terminal voltage and resistance of the lead acid batteries; then, the lead acid batteries are charged by adopting a variable constant current mode and balanced; when the voltage of the lead acid batteries approaches the upper limit charging voltage, the charging is finished and changed into constant-voltage charging; the trickle charging is carried out according to the capacity parameters of the lead acid batteries; and finally, a charging power supply is automatically cut off. The intelligent charging system and charging method disclosed by the invention can effectively solve the problem that bus bars and slab lattices are corroded, avoid accidents because of a temperature from occurring, can effectively protect the capacity of a battery pack and reach the purpose of saving energy.

Description

A kind of lead-acid battery intelligent charge system and charging method
Technical field
The present invention relates to a kind of lead-acid battery fast charge method and charging system.Belong to the lead-acid battery field.
Background technology
Lead acid accumulator is a kind of chemical power source, is the first-selection of cheap electrical source of power, and its raw material are easy to obtain, and uses reliably, is applicable to heavy-current discharge and applied environment temperature etc. widely.Lead acid accumulator commonly used has valve controlled sealed lead-acid accumulator, because " non-maintaining " property of analysing valve control type lead-acid accumulator battery, make some users misunderstand: to think that this battery does not need to safeguard fully, even after loading onto battery, just no longer carry out maintenance and management.In fact, the injury that " non-maintaining " of analysing valve control type lead-acid accumulator battery just avoided the acid gas of open type battery volatilization that equipment, personnel are caused has also made things convenient for and installed and transportation simultaneously, no longer artificial liquid feeding and oneself.But find that by long experiment valve controlled sealed lead-acid accumulator in use exists a lot of potential safety hazards, that is:
1, because charging current is excessive, makes that bus-bar and grid are corroded, cause metal path to narrow down and the internal resistance of battery is increased.
2, because float charge voltage is too high, accelerate gas purging in anode plate grid corrosion rate and the battery, cause drying up.
3, owing to be subjected to the too high influence of ambient temperature, make internal temperature of battery raise, cause floating current to increase, floating current increases, and accelerates internal temperature of battery again and raises, and forms vicious circle, causes thermal runaway.
4, owing to be subjected to the restriction of monomer battery voltage and electric current, the lead-acid battery energy-storage system generally all is to use after being composed in series the high pressure high power capacity again after a plurality of battery parallel connections, even through screening, the consistency of battery is better, also difference can occur after use after a while before forming.Through the repeatedly vicious circle of " floating charge → discharge → all fill → discharge → floating charge ", cause the entire cell pool-size constantly to descend.
5, conventional method is to adopt to float towards method to gather battery terminal voltage, but the battery terminal voltage measurement under the floating charge state itself can not truly reflect the performance condition of battery, even the battery of degradation also can record qualified terminal voltage when floating charge; In case and electric power system has a power failure, during battery discharging, just possibly can't guarantee the discharge requirement under the accident condition, thereby therefore expansion accident scope, need carry out on-line monitoring to accumulator cell charging and discharging.
Summary of the invention
The present invention be overcome deficiency that above-mentioned valve controlled sealed lead-acid accumulator discharges and recharges existence, for prolonging the useful life of lead-acid battery, reduce use cost and propose a kind of lead-acid battery intelligent charge system, the invention also proposes the charging method when adopting this charging system to charge.
The technical scheme that lead-acid battery intelligent charge of the present invention system adopts is: be made of controller and main circuit, controller comprises pwm control signal module, electric current, voltage detection module and temperature detecting module, main circuit comprises the reduction voltage circuit that 220V electric main and transformer W1 are connected to, transformer W1 links to each other with two inputs of rectifier D1, and an end of rectifier D1 two outputs links to each other with electrochemical capacitor C1 anode, the other end and electrochemical capacitor C1 negative electrode are connected to dc charging power supply; Electrochemical capacitor C1 anode links to each other with field effect transistor Q1 input, and field effect transistor Q1 output links to each other with sustained diode 2 outputs and inductance L 1 one ends, and inductance L 1 other end links to each other with electrochemical capacitor C2 anode; Sustained diode 2 inputs, electrochemical capacitor C2 negative electrode, electrochemical capacitor C1 negative electrode are connected to common port; Field effect transistor Q1 control end connects the pwm control signal module; Electrochemical capacitor C2 anode links to each other with inductance L 2 one ends, and inductance L 2 other ends link to each other with lead-acid battery E anode, and lead-acid battery E negative electrode links to each other with current transformer P one input, another input termination common port of current transformer P; Current transformer P output connects current detection module, and voltage detection module connects lead-acid battery E anode, and temperature detecting module connects the temperature sensor of lead-acid battery E.
Lead-acid battery intelligent charging method of the present invention is to adopt following steps:
1) in 0 ~ t1 charging period, controller detects terminal voltage and the internal resistance of lead-acid battery E by voltage, current detection module summation current transformer P and judges whether the lead-acid battery E of damage, if lead-acid battery E partly damages, with dc charging power supply its precharge is repaired, if the whole damages of lead-acid battery E maybe can not be repaired, controller blocks pwm signal and reports to the police;
2) become the constant current charge period fast at t1 ~ t2, controller control pwm signal high level, field effect transistor Q1 conducting, inductance L 1 electric current increases, and dc charging power supply is to electrochemical capacitor C2 charging, and 2 couples of lead-acid battery E of inductance L charge, and sustained diode 2 is ended; Step-down after the PWM high level pulse duration, sustained diode 2 conductings, inductance L 1 and electrochemical capacitor C2 charge to lead-acid battery E simultaneously; Another high level behind the pwm signal low duration makes field effect transistor Q1 conducting again, so repeats; Controller detects terminal voltage and the temperature of lead-acid battery E in good time;
3) charge mid-term at t2 ~ t3, controller regularly detects terminal voltage, temperature and the internal resistance of lead-acid battery E, determines the constant current that following a moment is best, with the constant current I1 that changes, I2, I3 ... the lead-acid battery E charging of In;
4) charge latter stage at t3 ~ t4, controller is judged the quality of every joint lead-acid battery E, as definite every joint lead-acid battery E when all functional and voltage approaches the charging upper voltage limit, changes constant voltage charge into;
5) controller enters the trickle charge of t4 ~ t5 period according to lead-acid battery E capacity parameter;
6) after trickle charge reaches the time of controller setting, if there is not the plug power supply, the t6 behind t5 controller constantly cuts off field effect transistor Q1 to cut off main circuit.
The beneficial effect that the present invention has is:
1, because the present invention arranges parameter according to the optimal charge curve of lead-acid battery fully, thus solved effectively problem that bus-bar and grid corroded,
2, because in charging process, controller is all monitored in the problem to battery constantly, so reduced the influence of temperature to battery performance, has avoided the generation of the accident that causes owing to temperature.
3, in the quick charge process since the time be engraved in the terminal voltage that detects battery, and the problematic battery of terminal voltage is carried out equilibrium, protected battery capacity effectively.
4, in lead-acid battery terminal voltage testing process, owing to parameters such as the internal resistance of having introduced plumbic acid, temperature, make terminal voltage more close to actual parameter.
Description of drawings
Fig. 1 is charging system connection layout of the present invention;
Fig. 2 is the charging curve of Fig. 1 control.
Embodiment
With reference to Fig. 1, charging system of the present invention is connected and composed by controller (MCU) and main circuit, and main circuit is by reduction voltage circuit, shaping circuit, and smoothing circuit, BUCK circuit summation current transformer P connect to form.Controller comprises pwm control signal module, current detection module, voltage detection module and temperature detecting module.Wherein, reduction voltage circuit is to be connected to form by 220V electric main and transformer W1; Transformer W1 links to each other with two inputs of rectifier D1, constitutes shaping circuit; One end of two outputs of rectifier D1 links to each other with the anode of electrochemical capacitor C1, and the other end links to each other with the negative electrode of electrochemical capacitor C1 and constitutes smoothing circuit, as dc charging power supply.The anode of electrochemical capacitor C1 links to each other with the input of field effect transistor Q1, and the output of field effect transistor Q1 links to each other with the output of sustained diode 2 and an end of inductance L 1, and the other end of inductance L 1 links to each other with the anode of electrochemical capacitor C2, constitutes the BUCK circuit; And the negative electrode of the negative electrode of the input of sustained diode 2, electrochemical capacitor C2, electrochemical capacitor C1 all connects together, and constitutes common port (ground wire); The control end of field effect transistor Q1 is by the pwm control signal module of wire connection controller, and pwm control signal is by controller control output.The anode of electrochemical capacitor C2 links to each other with an end of inductance L 2, the other end of inductance L 2 links to each other with the anode of lead-acid battery E to be charged, the negative electrode of lead-acid battery E links to each other with the input of current transformer P, and another input of current transformer P is connected with common port (ground wire); The output of current transformer P is by the current detection module of wire connection controller, and the voltage detection module of controller is received the anode of lead-acid battery E by lead, and the temperature detecting module of controller is received the temperature sensor of lead-acid battery E by lead.
With reference to Fig. 1-2, the present invention is along with the variation in charging interval, adopt the charge step of " precharge → become fast constant current charge → constant voltage charge → trickle charge " successively, control its whole process by controller: at the charging initial stage, controller is repaired the line precharge of going forward side by side according to parameters such as the lead-acid battery E terminal voltage that collects, internal resistances to the battery that the part damage is arranged; Then, charging mid-term, parameters such as the terminal voltage of periodic testing battery, temperature, internal resistance are taked to become the constant current measure to make charging curve approach the optimal charge curve, and lead-acid battery E are carried out equilibrium, make it reach consistency preferably; Charging latter stage, controller is according to parameters such as lead-acid battery E terminal voltage and internal resistances, when lead-acid battery E voltage approaches the charging upper voltage limit, lead-acid battery E quick charge finishes, and battery fills and changes constant voltage charge into, after trickle charge a period of time, automatically cut off charge power supply, reach purpose of energy saving.Concrete charge step is as follows:
1, the charging initial stage, i.e. 0 ~ t1 period of Fig. 2, controller at first parameter such as the terminal voltage by voltage, current detection module and the lead-acid battery E of current transformer P, internal resistance detects and is judged, judges the battery whether damage is arranged.If the dc charging power supply after the rectification can not charge, detecting is the lead-acid battery E that all damages, and controller just blocks pwm signal and reports to the police.Lead-acid battery E for local damage, with dc charging power supply it is carried out precharge, pre-charge process is the lead-acid battery E that can repair the part damage, dc charging power supply has the part of damage to repair with the fastest speed to it, if system can not repair the storage battery E of part damage, controller blocks pwm signal equally and reports to the police.
2, become constant current charge period fast, i.e. the t1 of Fig. 2 ~ t2 period, controller control pwm signal high level occurs, field effect transistor Q1 conducting, the electric current of inductance L 1 constantly increases, and DC power supply is charged to electrochemical capacitor C2, constantly stored energy is also charged to lead-acid battery E by inductance L 2 simultaneously; At this moment, sustained diode 2 is ended because of reverse bias.Process PWM high level pulse is after the duration, during the pwm signal step-down, field effect transistor Q1 ends, and the electric current in the inductance L 1 reduces, the induced electromotive force at L1 two ends makes sustained diode 2 conductings, and the storaging current in the inductance L 1 and capacitor C 2 stored charges charge to lead-acid battery E simultaneously.Through behind the low duration of pwm signal, the another high level pulse of pwm signal arrives, and makes field effect transistor Q1 conducting once again, and said process repeats to take place.For approaching the optimal charge curve, the constant current of lead-acid battery E is big and change very fast, the pwm signal that makes controller send changes very fast and changes bigger, this just requires controller to pass through the terminal voltage that voltage detection module detects lead-acid battery E in good time, and detect the temperature of lead-acid battery E, the life-span that prevents big electrical injuries lead-acid battery E by temperature detecting module in good time.
3, charge mid-term, it is t2 ~ t3 period of Fig. 2, this moment, the constant current conversion ratio of lead-acid battery E was slower, and this is that lead-acid battery E charging needs maximum time, will regularly detect the parameters such as terminal voltage, temperature, internal resistance of lead-acid battery E this moment, determine the constant current that following a moment is best, with the constant current I1 that changes, I2, I3 ... the lead-acid battery E charging of In, approach best curve, and according to the lead-acid battery E both end voltage value that detects the higher and lower battery of voltage is carried out equilibrium control.
4, charge latter stage, it is the t3 ~ t4 period of Fig. 2, parameters such as the terminal voltage of lead-acid battery E and internal resistance are sent to controller, judge the quality of every joint lead-acid battery E, as definite every joint lead-acid battery E when all functional and lead-acid battery E voltage approaches the charging upper voltage limit, lead-acid battery E quick charge finishes, and this moment, charging changed constant voltage charge into to lead-acid battery E.
5, controller detects and judges parameter such as lead-acid battery E capacity, and according to parameters such as lead-acid battery E capacity, after stage, lead-acid battery E carries out the trickle charge of t4 ~ t5 time period at constant voltage charge.
6, after trickle charge reaches the certain hour that controller sets, if there is not the plug power supply, the t6 behind t5 constantly, controller cuts off the field effect transistor Q1 among Fig. 1, make pwm control signal be output as 0, just cut off the charging main circuit automatically, reach the purpose of conserver power source.

Claims (2)

1. lead-acid battery intelligent charge system, constituted by controller and main circuit, controller comprises pwm control signal module, electric current, voltage detection module and temperature detecting module, main circuit comprises the reduction voltage circuit that 220V electric main and transformer W1 are connected to, it is characterized in that: described transformer W1 links to each other with two inputs of rectifier D1, and an end of rectifier D1 two outputs links to each other with electrochemical capacitor C1 anode, the other end and electrochemical capacitor C1 negative electrode are connected to dc charging power supply; Electrochemical capacitor C1 anode links to each other with field effect transistor Q1 input, and field effect transistor Q1 output links to each other with sustained diode 2 outputs and inductance L 1 one ends, and inductance L 1 other end links to each other with electrochemical capacitor C2 anode; Sustained diode 2 inputs, electrochemical capacitor C2 negative electrode, electrochemical capacitor C1 negative electrode are connected to common port; Field effect transistor Q1 control end connects the pwm control signal module; Electrochemical capacitor C2 anode links to each other with inductance L 2 one ends, and inductance L 2 other ends link to each other with lead-acid battery E anode, and lead-acid battery E negative electrode links to each other with current transformer P one input, another input termination common port of current transformer P; Current transformer P output connects current detection module, and voltage detection module connects lead-acid battery E anode, and temperature detecting module connects the temperature sensor of lead-acid battery E.
2. charging method that adopts the described charging system of claim 1 is characterized in that having following steps:
1) in 0 ~ t1 charging period, controller detects terminal voltage and the internal resistance of lead-acid battery E by voltage, current detection module summation current transformer P and judges whether the lead-acid battery E of damage, if lead-acid battery E partly damages, with dc charging power supply its precharge is repaired, if the whole damages of lead-acid battery E maybe can not be repaired, controller blocks pwm signal and reports to the police;
2) become the constant current charge period fast at t1 ~ t2, controller control pwm signal high level, field effect transistor Q1 conducting, inductance L 1 electric current increases, and dc charging power supply is to electrochemical capacitor C2 charging, and 2 couples of lead-acid battery E of inductance L charge, and sustained diode 2 is ended; Step-down after the PWM high level pulse duration, sustained diode 2 conductings, inductance L 1 and electrochemical capacitor C2 charge to lead-acid battery E simultaneously; Another high level behind the pwm signal low duration makes field effect transistor Q1 conducting again, so repeats the charging process that described t1 ~ t2 becomes the constant current charge period fast; Controller detects terminal voltage and the temperature of lead-acid battery E in good time;
3) charge mid-term at t2 ~ t3, controller regularly detects terminal voltage, temperature and the internal resistance of lead-acid battery E, determines the constant current at following a moment, with the constant current I1 that changes, I2, I3 ... the lead-acid battery E charging of In;
4) charge latter stage at t3 ~ t4, controller is judged the quality of every joint lead-acid battery E, as definite every joint lead-acid battery E when all functional and voltage approaches the charging upper voltage limit, changes constant voltage charge into;
5) controller enters the trickle charge of t4 ~ t5 period according to lead-acid battery E capacity parameter;
6) after trickle charge reaches the time of controller setting, if there is not the plug power supply, the t6 behind t5 controller constantly cuts off field effect transistor Q1 to cut off main circuit.
CN2011100797161A 2011-03-31 2011-03-31 Intelligent charging system of lead acid batteries and charging method CN102157975B (en)

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CN102403766B (en) * 2011-11-21 2014-09-17 苏州盖娅智能科技有限公司 Super capacitor charging method and system for realizing same
CN103855747B (en) * 2012-12-05 2017-02-08 凹凸电子(武汉)有限公司 battery system and battery charging method
US9368979B2 (en) 2013-03-15 2016-06-14 O2Micro Inc System and methods for battery balancing
GB2518759A (en) 2014-09-29 2015-04-01 Daimler Ag Battery management system for a motor vehicle
CN104505892A (en) * 2014-12-30 2015-04-08 贵州省电子工业研究所 Intelligent control system of charging and discharging battery pack
CN105656108A (en) * 2015-07-28 2016-06-08 宁波萨瑞通讯有限公司 Charging circuit system
CN105958143B (en) * 2016-05-23 2019-09-06 中国空间技术研究院 A kind of satellite lithium battery ground charging method and system

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